Can metaphyseal variations in the distal femurs and proximal tibias be distinguished from classic metaphyseal lesions?

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Boaz Karmazyn, Christopher L. Newman, Megan B Marine, Mathew R Wanner, and 9 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6831876/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 01 Oct, 2025 Read the published version in Pediatric Radiology → Version 1 posted 12 You are reading this latest preprint version Abstract Background: Classic metaphyseal lesions (CMLs) are considered specific for child abuse, but the reliability of radiologists in distinguishing CMLs from metaphyseal variations is unclear. Objective: To evaluate whether radiologists can differentiate between CMLs and metaphyseal variations in the knees. Materials and Methods: We performed a retrospective review of distal femur and proximal tibia radiographs in children under two years of age who underwent skeletal surveys for suspected child abuse. The CML group included children diagnosed with abuse and reported CMLs. The metaphyseal variation group included children not diagnosed with abuse, with reported metaphyseal variations and either no fractures or an isolated skull fracture. Radiographs were trimmed to exclude other injuries. Four pediatric and four general radiologists reviewed anonymized studies and categorized each case as CML, metaphyseal variation, normal, or indeterminate, with confidence levels (high, moderate, low). We analyzed diagnoses with moderate or high confidence. Interobserver agreement was assessed using kappa statistics. Results: There were 48 children with CMLs (40 initial, 38 follow-up) and 27 with metaphyseal variations (20 initial, 12 follow-up). Metaphyseal fragmentation was the most common variation, identified in 259 of 356 femurs (72.8%) and 69 of 83 tibias (83.1%). Fragmentations were most frequently located in the posterior or medial metaphysis, or both, in 257 of 259 femurs (99.2%) (257/259) and 68 of 69 tibias (98.6%). In the CML group, 34 of 115 initial CML diagnoses (29.4%) were read on follow-up as either metaphyseal variation (n=17) or normal (n=17). In contrast, in the metaphyseal variation group, only one follow-up case was diagnosed as a CML; the remainder were diagnosed as metaphyseal variation (n=22) or normal (n=2). Diagnostic performance for CML demonstrated high specificity (90.7%) and positive predictive value (94.9%), with moderate accuracy (76.1%), sensitivity (70.2%), and negative predictive value (55.2%). Interobserver agreement was substantial, with a mean kappa of 0.61. Conclusion : Radiologists demonstrated substantial agreement and high specificity in distinguishing CMLs from metaphyseal variations. Metaphyseal fragmentation was the most common variation and was uncommonly diagnosed as CML on follow-up. Classic metaphyseal lesion Infant Metaphyseal variation Skeletal survey Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction One of the unique challenges in evaluating fractures in children is to differentiate between normal variation and fracture [ 1 ]. This is especially critical when evaluating radiographs for child abuse. Missing fractures can have disastrous consequences and may lead to continued trauma to the child and handicap or even death [ 2 ]. On the other hand, overdiagnosis of injuries suggestive of child abuse can lead to unnecessary emotional distress and the removal of the child from the home. It is therefore important for radiologists to recognize metaphyseal variations. Classic metaphyseal lesion (CML) is a distinctive radiologic finding of either a corner fracture or bucket handle fracture that is highly specific for child abuse [ 3 – 7 ]. However, certain normal metaphyseal variations in infancy should be carefully distinguished from the CML [ 8 – 10 ]. Anatomically, the region of the growth plate that incorporates the groove and zone of Ranvier and the ring of Lacroix (all of which surround the physis and adjacent primary spongiosa) is called the periphysis [ 11 ]. The appearance of the periphysis varies with the anatomical region and radiographic projection. Two principal radiographic patterns, step-off and spur, should be recognized as normal anatomical structures [ 10 ]. Another variation, metaphyseal fragmentation that is localized to the distal femur and proximal tibia, was found to be associated with physiological bowing in children older than 15 months of age [ 9 ]. However, at our institution, we have also observed this variation in younger children with a low suspicion for nonaccidental trauma. This study aims to assess whether radiologists can accurately distinguish metaphyseal variations from CMLs. Materials and Methods Patient selection This study was approved by the institutional review board with a waiver of consent granted. This was a retrospective review of radiographic images of distal femurs and proximal tibias in children under two years of age who underwent a skeletal survey for suspected child abuse. Using our institution’s radiology information system (RIS), a pediatric radiologist with 27 years of experience post-fellowship, who did not participate in the imaging evaluation, retrospectively retrieved all skeletal surveys performed for evaluation of child abuse from 2007 to 2023. Two groups of patients were identified. The first group included children with a diagnosis of child abuse and reports of distal femur or proximal tibia CMLs. The second group included children that did not have a diagnosis of child abuse but who had reported distal femur or proximal tibial metaphyseal variation, with either no fractures or isolated accidental skull fracture, as isolated skull fracture has been found to be associated with a low risk for child abuse [ 12 ]. For the CML group, the RIS was searched using the keywords of “CML,” “classic metaphyseal lesion”, “corner fracture” or “bucket handle fracture”. For the metaphyseal variation group, the RIS was searched using the keywords of “irregularity,” “step off”, “beak”, “spur”, “fragmentation”, and “variation”. All reports were reviewed by the same pediatric radiologist, and only studies with reports referring to distal femur or proximal tibia in association with these keywords were selected. Two child abuse pediatricians who were not involved in image interpretation reviewed the electronic medical record (EMR). From the EMR, the following data were recorded: demographic information, history of prematurity, underlying medical diseases, the original radiologist interpretation of distal femur and proximal tibia findings, other injuries reported in the skeletal survey, and other imaging obtained to evaluate for abusive injuries. Patients with metabolic bone disease and bone dysplasia were excluded. The reports of neuroimaging studies were reviewed for the presence of subdural hematoma, parenchymal contusion or tear, parenchymal bleeding, and hypoxic-ischemic changes. If there was no history or medical conditions to adequately explain them, the presence of at least one of these findings was considered a sign of high likelihood of abusive head trauma. The EMR was reviewed for the presence of the following physical injuries: bruising, burn injuries, other skin injuries, retinal bleeding, subconjunctival hemorrhage, and torn frenula. The child abuse pediatrician’s report was reviewed and categorized as positive, negative, or indeterminate for the diagnosis of physical abuse. Children with an indeterminate diagnosis of child abuse were excluded. Radiograph selection and preparation We included initial and follow-up radiographs if available. Our routine skeletal surveys include anteroposterior (AP) and lateral radiographs of the long bones. From the skeletal surveys, the AP and lateral DICOM radiographs of the femurs and tibias were selected and anonymized. To minimize potential bias from other injuries visible on the radiographs, all images were trimmed by an experienced radiologic technologist under the supervision of a pediatric radiologist who was not involved in the image evaluation. Trimming was performed using the Santa DICOM Editor (Santsoft, Athens) to isolate the metaphysis of the distal femur, proximal tibia, or both, —depending on which structures were included in the original radiograph. Radiograph review DICOM images were reviewed independently by eight radiologists using a diagnostic high-resolution monitor on the Synapse PACS system (FUJIFILM Medical Systems, Lexington, MA). All evaluations were performed in a randomized order and blinded to clinical information. To prevent paired comparison, initial and follow-up radiographs were separated and randomized, ensuring that radiologists could not view corresponding studies concurrently. Four reviewers were pediatric radiologists, and four were general emergency radiologists. Data collection and management were conducted using a secure, web-based application (REDCap; Vanderbilt University, Nashville, TN). For each metaphysis, the radiologist had to select one of the following options: normal, variation, CML, indeterminate. If normal, variation, or CML were selected, the radiologist had to assign a level of confidence: low, moderate, or high. For diagnosing CML, radiologists identified corner or bucket-handle fractures (any healing stage), corner deformity, subphyseal lucency, or metaphyseal irregularity with a rough metaphyseal–physeal margin. Metaphyseal variation (Fig. 1 ) was diagnosed by the presence of step-off (acute discrete distal metaphyseal angulation), spur (longitudinal thin cortical projection beyond the metaphyseal edge), or fragmentation (metaphyseal corner fragmentation oriented along the shaft), with the specific location (medial, lateral, anterior, or posterior) noted. The location was described as either affecting the entire metaphysis or at least one of the following locations: medial, lateral, anterior, or posterior metaphysis. Before the formal image review session, a pilot training session was conducted using 11 cases that did not meet the study’s inclusion criteria and were therefore excluded from the final cohort. These cases included six metaphyseal variations, four classic metaphyseal lesions (CMLs), and one indeterminate metaphyseal irregularity. The annotated cases were subsequently presented to the readers, to familiarize them with the spectrum of appearances and reinforce the classification criteria. Statistical analysis Fisher’s exact tests and two-sample t-tests were used to compare the CML and metaphyseal variation groups for differences in patient characteristics. Agreement between radiologists was evaluated using crosstabs, percentage agreement, and kappa statistics. Kappa values of 0.01–0.20 were considered as none to slight, 0.21–0.40 as fair, 0.41– 0.60 as moderate, 0.61–0.80 as substantial, and 0.81–1.00 as almost perfect agreement. For sensitivity and specificity calculations, a true positive diagnosis was defined as follows: a diagnosis of CML was considered correct for children in the CML group, and a diagnosis of metaphyseal variation was considered correct for children in the metaphyseal variation group. Generalized linear mixed models (GLMMs) were used to obtain combined estimates across all radiologists for accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). The GLMMs accounted for correlation among readings from multiple radiologists for each patient and for correlation among readings of all patients for each radiologist. GLMMs were then used to compare pediatric and general emergency radiologists for differences in the percentages of correct interpretations. GLMMs were also used to compare patients with metaphyseal variation and CML for differences in the frequencies of radiographic signs typically associated with metaphyseal variation (metaphyseal step off, beak, spur, fragmentation) and radiographic signs typically associated with CML (corner fracture, bucket-handle fracture, subphyseal lucency, metaphyseal irregularity). Results Patient population Figure 2 illustrates the flowchart of patient selection. A total of 54 children were initially reported to have (CMLs involving the distal femur or proximal tibia. Six children were excluded for the following reasons: presence of casting material on radiographs (n = 3), treatment with topiramate (n = 1), intraosseous needle evident on imaging (n = 1), and lack of a diagnosis of child abuse (n = 1). The final cohort included 48 children with radiology reports of CML, who underwent 78 skeletal surveys: 40 initial and 38 follow-up studies. Similarly, 54 children had reports indicating metaphyseal variation in the distal femur or proximal tibia. Of these, 27 were excluded due to a definite (n = 13) or indeterminate (n = 8) diagnosis of child abuse, postmortem evaluation (n = 2), absence of a lateral view (n = 2), presence of subcutaneous emphysema (n = 1), or limited clinical information (n = 1). The final metaphyseal variation group included 27 children who underwent a total of 32 skeletal surveys: 20 initial and 12 follow-ups. Children in the CML group were significantly younger than those in the metaphyseal variation group (mean age 3 months; range: 1–12 months vs. mean age 7 months; range: 1–20 months; p = 0.0005). The CML group comprised 30 males (62.5%) and 18 females (37.5%), while the metaphyseal variation group included 20 males (74.1%) and 7 females (25.9%), with no statistically significant sex distribution difference between groups ( p = 0.4445). Injuries other than CML in the distal femurs and proximal tibias Table 1 summarizes the injuries in the study population. Among children in the CML group, 28 of 48 (58.3%) had other physical injuries, most commonly bruising (21/48, 43.8%), compared to only one child in the metaphyseal variation group, who had a torn frenulum. Table 1 Summary of injuries found on physical examination and imaging in classic metaphyseal lesions (CMLs) and metaphyseal variations groups CML (n = 48) MV(n = 27) P- values Physical examination- any injury 28 (58.3%) 1 (3.7%) < 0.001 Bruising 21 (43.8%) 0 (0%) < 0.001 Burn injury 1 (2.1%) 0 (0%) 1.00 Retinal bleeding 3 (6.3%) 0 (0%) 0.549 Subconjunctival H 3 (6.3%) 0 (0%) 0.549 Torn frenulum 5 (10.4%) 1 (3.7%) 0.410 Head trauma 11 (22.9%) 3 (11.1%) 0.355 Subdural 10 (20.8%) 3 (11.1%) 0.355 Parenchymal contusion 4 (8.3%) 0 (0%) 0.290 Parenchymal bleeding 1 (2.1%) 0 (0%) 1.00 Acute ischemia 3 (6.3%) 0 (0%) 0.549 Venous thrombosis 1 (2.1%) 0 (0%) 1.00 Fractures 45 (93.8%) 8 (29.6%) < 0.001 Skull 4 (8.3%) 8 (29.6%) 0.023 Ribs 24 (50%) 0 (0%) < 0.001 Upper extremity 24 (50%) 0 (0%) < 0.001 Lower extremity 32 (66.7%) 0 (0%) < 0.001 Spine 1 (2.1%) 0 (0%) 1.00 Hands 3 (6.3%) 0 (0%) 0.549 Feet 1 (2.1%) 0 (0%) 1.00 Pelvis 1 (2.1%) 0 (0%) 1.00 Others 7 (14.6%) 0 (0%) 0.045 CML- classic metaphyseal lesions, MV- metaphyseal variation, PE- physical examination, H- hemorrhage Abusive head trauma was diagnosed in 11 of 48 children (22.9%) in the CML group, with subdural hematoma being the most common finding (10/48, 20.8%). Three children in the metaphyseal variation group had small focal subdural hematomas—two adjacent to a skull fracture and one associated with benign enlargement of the subarachnoid space. Fractures other than distal femur or proximal tibia CMLs were identified in 45 of 48 children (93.8%) with CMLs. The most common locations were the ribs (24/48, 50.0%), lower extremities (32/48, 66.7%), and upper extremities (24/48, 50.0%). Additionally, 24 of 48 children (50.0%) in the CML group had other CMLs, primarily in the lower (23/48, 47.9%) and upper extremities (7/48, 14.6%). In contrast, eight of 27 children (29.6%) in the metaphyseal variation group had skull fractures. Diagnostic accuracy of radiologists (moderate to high confidence) Table 2 summarizes diagnostic performance. Overall, radiologists demonstrated moderate diagnostic accuracy (76.1%) and sensitivity (70.2%), with high specificity (90.7%) and PPV (94.9%). The NPV was moderate at 55.2%. Table 2 Accuracy of radiologists to diagnose classic metaphyseal lesions All studies (n = 110) P value Outcome All Ped Gen Accuracy 76.1% 80.4% 71.7% 0.001 Sensitivity 70.2% 74.8% 65.6% 0.003 Specificity 90.7% 93.5% 87.5% 0.162 PPV 94.9% 96.4% 93.2% 0.200 NPV 55.2% 61.2% 49.4% 0.002 PPV = Positive predictive value, NPV-negative predictive value, Ped- pediatric radiologists, Gen- general emergency radiologists Pediatric radiologists outperformed their general radiology counterparts, with significantly higher accuracy (80.4% vs. 71.7%, p = 0.001), sensitivity (74.8% vs. 65.6%, p = 0.003), and NPV (61.2% vs. 49.4%, p = 0.002). No significant differences were found in specificity (93.5% vs. 87.5%, p = 0.162) or PPV (94.9% vs. 96.4%, p = 0.20). Diagnostic performance was better at the initial visit compared to follow-up, with significantly higher accuracy, sensitivity, and NPV (all p = 0.002). However, specificity ( p = 0.22) and PPV did not differ between visits ( p = 0.559). Change between initial and follow-up radiographs In the CML group, 30 children had both initial and follow-up radiographs (Table 3 ). Radiologists identified CML with moderate or high confidence in 115 of 154 studies (74.7%). On initial imaging, CMLs were diagnosed in 81 of 115 children (70.4%). An additional nine children were diagnosed as having CMLs on follow-up radiographs: four originally diagnosed as metaphyseal variation and five as normal. Table 3 Changes in moderate and high confidence diagnoses from initial to follow-up reads by all eight radiologists in the classic metaphyseal lesions (CMLs) and metaphyseal variation groups Follow-up Radiologist CML Metaphyseal variation Normal Total Initial CML Patients (n = 154) All CML 81 (70.4%) 17 (14.8%) 17 (14.8%) 115 (74.7%) Metaphyseal variation 4 (17.4%) 9 (39.1%) 10 (43.5%) 23 (14.9%) Normal 5 (31.3%) 2 (12.5%) 9 (56.3%) 16 (10.4%) Total 90 (58.4%) 28 (18.2%) 36 (23.4%) 154 Pediatric radiologists CML 47 (73.4%) 10 (15.6%) 7 (10.9%) 64 (81.0%) Metaphyseal variation 1 (10.0%) 5 (50.0%) 4 (40.0%) 10 (12.7%) Normal 2 (40.0%) 1 (20.0%) 2 (40.0%) 5 (6.3%) Total 50 (63.3%) 16 (20.3%) 13 (16.5%) 79 General radiologists CML 34 (66.7%) 7 (13.7%) 10 (19.6%) 51 (68.0%) Metaphyseal variation 3 (23.1%) 4 (30.8%) 6 (46.2%) 13 (17.3%) Normal 3 (27.3%) 1 (9.1%) 7 (63.6%) 11 (14.7%) Total 40 (53.3%) 12 (16.0%) 23 (30.7%) 75 Metaphyseal Variation Patients (n = 25) All Metaphyseal variation 1 (4.3%) 22 (95.7%) 0 23 (92.0%) Normal 0 2 (100.0%) 0 2 (8.0%) Total 1 (4.0%) 24 (96.0%) 0 25 Pediatric radiologists CML 0 0 0 Metaphyseal variation 0 14 (100.0%) 0 14 (100.0%) Normal 0 0 Total 0 14 (100.0%) 0 14 General radiologists CML Metaphyseal variation 1 (11.1%) 8 (88.9%) 0 9 (81.8%) Normal 0 (< 0.1%) 2 (100.0%) 0 2 (18.2%) Total 1 (9.1%) 10 (90.9%) 0 11 Notably, 34 of 115 children (29.4%) initially diagnosed with CML were reclassified on follow-up as having metaphyseal variation (n = 17) or a normal metaphysis (n = 17) (Fig. 3 ). In the metaphyseal variation group, five children had both initial and follow-up radiographs. Only one follow-up study was interpreted as CML, by a general radiologist. All others were interpreted as metaphyseal variation (n = 22, Fig. 4 ) or normal (n = 2). Location-based analysis of CMLs and metaphyseal variations (all confidence levels) Tables S1 and S2 summarize the locations of metaphyseal variants and CMLs in the femurs and tibias. In the CML group, abnormalities were 1.4 times more common in the femur than in the tibia. CMLs were identified in 410 of 624 (65.7%) femurs and 286 of 624 (45.8%) tibias. In the metaphyseal variation group, abnormalities were four times more common in the femurs as compared with the tibias. Variants were identified in 169 of 256 (66.0%) femurs and 42 of 256 (16.4%) tibias. Among metaphyseal variants, fragmentation was most common: 259 of 356 femoral lesions (72.8%) and 69 of 83 tibial lesions (83.1%). This was followed by metaphyseal spurs, with 61 of 356 femurs (17.1%) and five of 83 tibias (6.0%), and meta (10.8%) physeal step-off, seen in 36 femurs (10.1%) and nine tibias (10.8%). Metaphyseal fragmentation demonstrated a highly consistent distribution, occurring in the posterior and/or medial metaphyses in 257 of 259 femurs (99.2%) and 68 of 69 tibias (98.6%). Metaphyseal spurs were most commonly identified in the anterior and/or lateral metaphyses in 50 of 61 femurs (82.0%). In contrast, the five spurs observed in the tibias were distributed across variable locations without a dominant pattern. Metaphyseal step-offs, when confined to a single location, were equally distributed between the medial and lateral metaphyses of the femur (11 of 36 each; 30.6%). In four of 36 cases (11.1%), the step-off involved the posterior metaphysis in combination with either the medial or lateral side. One case demonstrated involvement of both medial and lateral metaphyses. In the tibia, step-offs were predominantly located in the medial metaphysis, observed in seven of nine cases (77.8%). Classic metaphyseal lesion (CML) signs involved the entire metaphysis or at least three metaphyseal locations in 84 of 257 femurs (32.7%) and 80 of 177 tibias (45.2%). In contrast, metaphyseal variations involved the entire metaphysis or ≥ 3 locations in only one of 356 femurs (0.3%) and one of 83 tibias (1.2%). Confidence comparison There was no difference ( p = 0.113) in the proportion of low-confidence or indeterminate diagnoses between pediatric and general radiologists, occurring in 78 of 440 (17.7%) and 94 of 440 (21.4%) of the cases, respectively. Agreement between radiologists The average agreement between radiologists was substantial (kappa = 0.61), ranging from moderate to substantial (kappa of 0.41 to 0.78) between radiologist pairs (Table 4 ). The most experienced pediatric radiologists demonstrated the highest agreement (kappa = 0.78). Table 4 Agreement between radiologists on diagnosis of classic metaphyseal lesions and metaphyseal variations Kappa (95% CI) Pair All Initial Follow-up Pediatric 1 and 2 0.78 (0.65 to 0.91) 0.79 (0.62 to 0.97) 0.75 (0.55 to 0.95) 1 and 3 0.56 (0.38 to 0.73) 0.55 (0.31 to 0.78) 0.54 (0.27 to 0.80) 1 and 4 0.57 (0.40 to 0.74) 0.45 (0.22 to 0.69) 0.67 (0.44 to 0.91) 2 and 3 0.65 (0.51 to 0.80) 0.72 (0.53 to 0.91) 0.57 (0.35 to 0.79) 2 and 4 0.60 (0.46 to 0.74) 0.60 (0.41 to 0.80) 0.58 (0.38 to 0.79) 3 and 4 0.51 (0.36 to 0.66) 0.44 (0.23 to 0.66) 0.56 (0.35 to 0.77) Average 0.61 0.59 0.61 General 1 and 2 0.49 (0.35 to 0.64) 0.48 (0.29 to 0.68) 0.49 (0.27 to 0.70) 1 and 3 0.48 (0.30 to 0.66) 0.41 (0.17 to 0.65) 0.53 (0.27 to 0.79) 1 and 4 0.41 (0.26 to 0.55) 0.41 (0.22 to 0.60) 0.39 (0.16 to 0.61) 2 and 3 0.63 (0.45 to 0.80) 0.54 (0.27 to 0.81) 0.66 (0.41 to 0.91) 2 and 4 0.70 (0.56 to 0.84) 0.57 (0.35 to 0.79) 0.81 (0.63 to 0.98) 3 and 4 0.61 (0.43 to 0.80) 0.62 (0.36 to 0.87) 0.59 (0.31 to 0.86) Average 0.55 0.50 0.58 All Average 0.61 0.59 0.59 Discussion Our study demonstrates that CMLs can be distinguished from metaphyseal variations with high specificity and positive predictive values, and that metaphyseal fragmentation is the most common variation, predominantly occurring in the distal femur. There are few studies on metaphyseal variations that can mimic CMLs. In 408 children under two years = old who were admitted to the emergency department for suspected trauma, Eide et al. reported an incidence of 16.3% for metaphyseal collar and 8.6% for irregular metaphysis variations [ 13 ]. Kleinman et al. found step-off variation in 3% of the distal femurs in a study of 78 postmortem examinations in patients with sudden infant death syndrome [ 10 ]. The challenge in differentiating metaphyseal variations from CMLs has been highlighted in a few studies. Karmazyn et al. reported that following a double read of outside studies of skeletal surveys, four of 19 CMLs diagnosed by outside radiologists were read as metaphyseal variants by a pediatric radiologist [ 14 ]. Kleinman et al. reported that in one child metaphyseal fragmentation was misinterpreted as a CML, prompting a child abuse evaluation including skeletal survey [ 9 ]. A similar misdiagnosis was documented in another case report [ 15 ]. Our study is the first to evaluate the accuracy of radiologists in differentiating between CMLs and metaphyseal variations. Our study was focused on the knees, as from our experience this is the most common location where metaphyseal variations are misinterpreted as CMLs. This is also the most common location of CMLs [ 16 ]. On average, the agreement between radiologists in our study was substantial (kappa = 0.61) with no significant difference in the rate of low confidence diagnosis between pediatric and general radiologists. The most experienced pair of pediatric radiologists had the highest agreement (kappa = 0.78). Both groups of radiologists had high specificity (90.7%) and PPV (94.9%) with no significant difference between them. These findings suggest that when radiologists diagnose CMLs, there is a high probability that the diagnosis is correct. However, there was moderate sensitivity (70.2%) and NPV (55.2%). The pediatric radiologists performed significantly better than the general radiologists in both sensitivity and NPV, suggesting they may be better at detection of CMLs. Diagnostic performance was significantly better at the initial visit compared to the follow-up, with higher accuracy, sensitivity, and NPV, whereas specificity and PPV did not show a significant difference. This suggests that the ability to reliably diagnose CML was better on the initial compared to follow-up radiographs. This reduced accuracy at follow-ups can be explained by healing and normalization of the CML on follow-up radiographs [ 17 ]. Metaphyseal fragmentation was the most common metaphyseal variation that was identified. Compared with the study of Kleinman et al. [ 9 ] our study shows that this variation also occurs in infants. In contrast to signs related to CMLs, which in about a third of femurs and tibias involve the entire metaphysis or at least three metaphyseal locations, metaphyseal fragmentation involved only the medial and/or posterior metaphyses in 244 of 259 (94.2%) femurs and in 68 of 69 (98.6%) tibias. In the CML group, four children initially diagnosed with metaphyseal variation and five initially diagnosed with normal metaphyses were diagnosed on follow-up radiographs as CML. This confirms the importance of follow-up radiographs. In a study by Kleinman et al., most new fractures identified on follow-up skeletal survey involved CMLs and ribs [ 18 ]. In the metaphyseal variation group, only one general radiologist diagnosed CML on follow-up radiographs, suggesting that metaphyseal variations diagnosed on initial radiographs are unlikely to be diagnosed as a CML on follow-up skeletal survey. CML is considered highly specific for child abuse. Therefore, its presence should raise suspicion for abuse, even if it is the only detected lesion [ 3 ]. However, CMLs rarely occur in isolation without other fractures [ 7 , 16 ]. Notably, most children in the metaphyseal variation group in our study had no other fractures, and about a third had only a skull fracture. Radiologists should be especially prudent when metaphyseal changes appear in isolation, as misinterpreting metaphyseal variations as CMLs could significantly impact both medical and child protection management. Our study has several limitations. There was no gold standard for the diagnosis of CML and metaphyseal variations. Instead, cases were diagnosed based on clinical and imaging findings. There was as small sample of follow-up radiographs, with only five children in the metaphyseal variation group that had follow-up radiographs, potentially limiting our assessment of change in radiologists’ interpretation between initial and follow-up radiographs. In addition, radiologists were blinded to prior radiographs and ultrasound studies that are occasionally used in challenging cases, which could result in the incorrect diagnosis of healing CMLs as metaphyseal variations or as normal on follow-up radiographs. In summary, we found substantial agreement between radiologists in the evaluation of CMLs and metaphyseal variations of the distal femur and proximal tibia. Radiologists had high specificity and positive predictive value in the diagnosis of CMLs, and pediatric radiologists performed significantly better than the general radiologists in both sensitivity and negative predictive value, suggesting they may be better at detection of CMLs. Metaphyseal fragmentation was the most common type of metaphyseal variation, predominantly located in the medial and posterior metaphysis of the distal femur. Importantly, metaphyseal variations identified on initial radiographs were unlikely to be later diagnosed as CMLs on follow-up imaging. Declarations This study was approved by the Institutional Review Board. Conflict of interest: The authors declare no competing interests. Funding: There was no funding for the study. Author Contribution Boaz Karmazyn conceptualized and designed the study and drafted the initial manuscript.Christopher L. Newman performed image review and revised the study.Megan B Marine performed images review. Mathew R Wanner performed images review. Jared R Shield performed images review. Scott D Steenburg performed images review. Alexander G Boutselis performed images review. Jordan H Cuskaden performed images review. Eric D Westin performed images review. Marrisa Luma M.D, assisted with clinical data collection.George J Eckert assisted in the statistical analysis and revised the study.Greg S Jennings assisted in conceptualizing and designing the study and critically revised the study.Ralph A Hicks assisted in conceptualizing and designing the study, assisted with clinical data analysis.All authors reviewed and approved the final manuscript. Acknowledgement We thank Wendy Territo for trimming the radiographs of the femurs and tibias Data Availability: The data that support the findings of this study are available from the corresponding author upon reasonable request. Due to the nature of clinical data and patient privacy regulations, the data are not publicly available. References Tougas C, Brimmo O (2022) Common and Consequential Fractures That Should Not Be Missed in Children. Pediatr Ann 51:e357–e363 Oral R, Yagmur F, Nashelsky M, Turkmen M, Kirby P (2008) Fatal abusive head trauma cases: consequence of medical staff missing milder forms of physical abuse. Pediatr Emerg Care 24:816–821 Flaherty EG, Perez-Rossello JM, Levine MA, Hennrikus WL (2014) Evaluating children with fractures for child physical abuse. Pediatrics 133:e477–489 Kleinman PK, Perez-Rossello JM, Newton AW, Feldman HA, Kleinman PL (2011) Prevalence of the classic metaphyseal lesion in infants at low versus high risk for abuse. AJR Am J Roentgenol 197:1005–1008 Eide P, Djuve A, Myklebust R, Forseth KF, Nottveit A, Brudvik C, Rosendahl K (2019) Prevalence of metaphyseal injury and its mimickers in otherwise healthy children under two years of age. Pediatr Radiol 49:1051–1055 Adamsbaum C, De Boissieu P, Teglas JP, Rey-Salmon C (2019) Classic Metaphyseal Lesions among Victims of Abuse. J Pediatr 209:154–159e152 Thackeray JD, Wannemacher J, Adler BH, Lindberg DM (2016) The classic metaphyseal lesion and traumatic injury. Pediatr Radiol 46:1128–1133 Quigley AJ, Stafrace S (2014) Skeletal survey normal variants, artefacts and commonly misinterpreted findings not to be confused with non-accidental injury. Pediatr Radiol 44:82–93 quiz 79–81 Kleinman PK, Sarwar ZU, Newton AW, Perez-Rossello JM, Rebello G, Herliczek TW (2009) Metaphyseal fragmentation with physiologic bowing: a finding not to be confused with the classic metaphyseal lesion. AJR Am J Roentgenol 192:1266–1268 Kleinman PK, Belanger PL, Karellas A, Spevak MR (1991) Normal metaphyseal radiologic variants not to be confused with findings of infant abuse. AJR Am J Roentgenol 156:781–783 Oestreich AE, Ahmad BS (1992) The periphysis and its effect on the metaphysis: I. Definition and normal radiographic pattern. Skelet Radiol 21:283–286 Leventhal JM, Martin KD, Asnes AG (2010) Fractures and traumatic brain injuries: abuse versus accidents in a US database of hospitalized children. Pediatrics 126:e104–115 Eide P, Djuve Å, Myklebust R, Forseth KF, Nøttveit A, Brudvik C, Rosendahl K (2019) Prevalence of metaphyseal injury and its mimickers in otherwise healthy children under two years of age. Pediatr Radiol 49:1051–1055 Karmazyn B, Wanner MR, Marine MB, Tilmans L, Jennings SG, Hibbard RA (2019) The added value of a second read by pediatric radiologists for outside skeletal surveys. Pediatr Radiol 49:203–209 Norrell K, Hennrikus W (2017) The Risk of Assuming Abuse in an Infant with an Isolated Metaphyseal Lesion: A Case Report. JBJS Case Connect 7:e69 Barber I, Perez-Rossello JM, Wilson CR, Kleinman PK (2015) The yield of high-detail radiographic skeletal surveys in suspected infant abuse. Pediatr Radiol 45:69–80 Karmazyn B, Marine MB, Wanner MR, Sağlam D, Jennings SG, Hibbard RA (2020) Establishing signs for acute and healing phases of distal tibial classic metaphyseal lesions. Pediatr Radiol 50:715–725 Kleinman PK, Nimkin K, Spevak MR, Rayder SM, Madansky DL, Shelton YA et al (1996) Follow-up skeletal surveys in suspected child abuse. AJR Am J Roentgenol 167:893–896 Additional Declarations No competing interests reported. Supplementary Files SupplementalTable1.docx Supplementary Table 1. Location of the radiographic signs within the metaphysis in the femurs Supplemetaltable2.docx Supplementary Table 2. Location of the radiographic signs within the metaphysis in the tibias Cite Share Download PDF Status: Published Journal Publication published 01 Oct, 2025 Read the published version in Pediatric Radiology → Version 1 posted Editorial decision: Revision requested 02 Jul, 2025 Reviews received at journal 24 Jun, 2025 Reviews received at journal 24 Jun, 2025 Reviewers agreed at journal 17 Jun, 2025 Reviewers agreed at journal 14 Jun, 2025 Reviews received at journal 13 Jun, 2025 Reviewers agreed at journal 12 Jun, 2025 Reviewers agreed at journal 11 Jun, 2025 Reviewers invited by journal 11 Jun, 2025 Editor assigned by journal 09 Jun, 2025 Submission checks completed at journal 09 Jun, 2025 First submitted to journal 05 Jun, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6831876","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":471263503,"identity":"e8834660-2a7d-48a9-80ea-c1d9eeba8603","order_by":0,"name":"Boaz Karmazyn","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAvUlEQVRIiWNgGAWjYBACex4og58ZRLIRocWwB8qQbCZWi8EZGOMA8bYcfvbpRk1d4ubjPAYMH8oOE9Ziz9tmPDvnGFvitsM8BowzzhGhxbCfwZg5h40HrIWZt40ILQbn2T8z5/yTSNzcDNTylygtZ3uMmXPbDBI3MAO1MBKjxbDnTDFzbl+C8YzDbAUHe86lE9Ziz5O+mTnnW51sf//hjQ9+lFkT1gIDjg1A4gDx6kG2kaR6FIyCUTAKRhYAALnYOFO+SpSPAAAAAElFTkSuQmCC","orcid":"","institution":"Riley Hospital for Children at IU Health, Department of Radiology and Imaging Sciences, Indiana University School of Medicine","correspondingAuthor":true,"prefix":"","firstName":"Boaz","middleName":"","lastName":"Karmazyn","suffix":""},{"id":471263505,"identity":"666b250c-379d-4caa-938f-fd0da1745dba","order_by":1,"name":"Christopher L. Newman","email":"","orcid":"","institution":"Riley Hospital for Children at IU Health, Department of Radiology and Imaging Sciences, Indiana University School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Christopher","middleName":"L.","lastName":"Newman","suffix":""},{"id":471263506,"identity":"dad092d1-32bf-4b40-9a49-0fba3a299a29","order_by":2,"name":"Megan B Marine","email":"","orcid":"","institution":"Riley Hospital for Children at IU Health, Department of Radiology and Imaging Sciences, Indiana University School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Megan","middleName":"B","lastName":"Marine","suffix":""},{"id":471263507,"identity":"b4fa1d20-96e2-4023-942d-8d98cfa5ee0c","order_by":3,"name":"Mathew R Wanner","email":"","orcid":"","institution":"Riley Hospital for Children at IU Health, Department of Radiology and Imaging Sciences, Indiana University School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Mathew","middleName":"R","lastName":"Wanner","suffix":""},{"id":471263508,"identity":"9528e4ad-d2ff-49a4-8103-7ce878f79000","order_by":4,"name":"Jared R Shields","email":"","orcid":"","institution":"Riley Hospital for Children at IU Health, Department of Radiology and Imaging Sciences, Indiana University School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Jared","middleName":"R","lastName":"Shields","suffix":""},{"id":471263509,"identity":"3842e0f8-f250-4a6b-8ce8-61ae5e08e316","order_by":5,"name":"Scott D Steenburg","email":"","orcid":"","institution":"Department of Radiology and Imaging Sciences, Indiana University School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Scott","middleName":"D","lastName":"Steenburg","suffix":""},{"id":471263510,"identity":"2469cb1a-b220-4050-87c4-88c894f63d7d","order_by":6,"name":"Alexander G Boutselis","email":"","orcid":"","institution":"Department of Radiology, Mayo Clinic, Scottsdale, Arizona","correspondingAuthor":false,"prefix":"","firstName":"Alexander","middleName":"G","lastName":"Boutselis","suffix":""},{"id":471263511,"identity":"08612c8b-ca1c-430b-9913-4b6a944e3a90","order_by":7,"name":"Jordan H Cuskaden","email":"","orcid":"","institution":"Department of Radiology and Imaging Sciences, Indiana University School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Jordan","middleName":"H","lastName":"Cuskaden","suffix":""},{"id":471263512,"identity":"9815a5c3-ddff-4ef2-8d82-382a87d274a4","order_by":8,"name":"Eric D Westin","email":"","orcid":"","institution":"Department of Radiology and Imaging Sciences, Indiana University School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"Eric","middleName":"D","lastName":"Westin","suffix":""},{"id":471263513,"identity":"5d9c140d-d14f-4707-a0e0-03a0b9eea138","order_by":9,"name":"Marrisa Luma","email":"","orcid":"","institution":"Department of Pediatrics, Section of Child Protection Programs, Indiana University School of Medicine, Riley Hospital for Children","correspondingAuthor":false,"prefix":"","firstName":"Marrisa","middleName":"","lastName":"Luma","suffix":""},{"id":471263514,"identity":"28960490-f5c3-4632-9d8e-1bebb4158a29","order_by":10,"name":"S. Gregory Jennings","email":"","orcid":"","institution":"Department of Radiology and Imaging Sciences, Indiana University School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"S.","middleName":"Gregory","lastName":"Jennings","suffix":""},{"id":471263515,"identity":"9c96898e-31f9-447f-b65f-40896151ff12","order_by":11,"name":"George J Eckert","email":"","orcid":"","institution":"Department of Biostatistics and Health Data Science, Indiana University School of Medicine","correspondingAuthor":false,"prefix":"","firstName":"George","middleName":"J","lastName":"Eckert","suffix":""},{"id":471263516,"identity":"75d2f688-37f5-420f-840e-5b8fd5a21f62","order_by":12,"name":"Ralph A Hicks","email":"","orcid":"","institution":"Department of Pediatrics, Section of Child Protection Programs, Indiana University School of Medicine, Riley Hospital for Children","correspondingAuthor":false,"prefix":"","firstName":"Ralph","middleName":"A","lastName":"Hicks","suffix":""}],"badges":[],"createdAt":"2025-06-05 20:23:22","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6831876/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6831876/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s00247-025-06398-w","type":"published","date":"2025-10-01T15:57:37+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":84776868,"identity":"d80735d9-6ece-4c28-8584-2a3ccc217ae9","added_by":"auto","created_at":"2025-06-17 09:06:34","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":3572794,"visible":true,"origin":"","legend":"\u003cp\u003eMetaphyseal variations\u003c/p\u003e\n\u003cp\u003eA. Metaphyseal fragmentation variation in a 3 month-old girl. Anteroposterior (AP) radiograph of the right knee demonstrates bony fragmentation extending proximally from the distal medial femoral metaphyseal corner (arrow).\u003c/p\u003e\n\u003cp\u003eB. Lateral radiograph of the right knee shows corresponding posterior metaphyseal fragmentation (arrow).\u003c/p\u003e\n\u003cp\u003eC. Metaphyseal spur variation in a 4 month-old boy. AP radiograph of the right knee demonstrates a discrete longitudinal projection of bone (arrow) that is continuous with the cortex and extends beyond the metaphyseal margin.\u003c/p\u003e\n\u003cp\u003eD. Metaphyseal step off variation in a 7 month-old boy. AP radiograph of the right knee demonstrates an acutecortical angulation at the junction of the distal lateral metaphysis and the physis (arrow).\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-6831876/v1/10f660cb7fa89fe57e26d0b6.png"},{"id":84776863,"identity":"92ba0c88-ff1d-4ed2-b251-f73eceef5e29","added_by":"auto","created_at":"2025-06-17 09:06:34","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":57213,"visible":true,"origin":"","legend":"\u003cp\u003eFlow chart of patients with classic metaphyseal lesions and metaphyseal variations\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-6831876/v1/5414e7a3f5946197ba133613.png"},{"id":84778221,"identity":"be0c25cb-c013-4873-85d0-94b633a7a2c9","added_by":"auto","created_at":"2025-06-17 09:14:34","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":2920174,"visible":true,"origin":"","legend":"\u003cp\u003eInitial reading of classic metaphyseal lesion (CML) in a 7 month-old male that in a blinded review by the radiologists was read as metaphyseal variant. The child presentedwith painful movement of his left upper extremity, with no known trauma. Radiography showed a spiral fracture of the left distal humerus. An initial skeletal survey diagnosed a distal left femoral CML with a subtle bucket handle fracture in the medial (arrow) and lateral metaphysis (arrowhead). Five radiologists reviewing the follow-up radiographs blinded to clinical history and prior radiographs read this as metaphyseal variation with moderate to high confidence, one as normal, one as low confidence CML, and one as low confidence metaphyseal variation. The AP radiograph shows distal femur medial corner irregularity (arrow) and medial metaphysis spur (arrowhead). The clinical radiology report, that was also based on US performed at the same time, demonstrated a healing CML. C. Longitudinal view of the medial distal right femur shows a normal metaphyseal collar (arrowhead) and irregular thickened left metaphyseal collar compatible with healing CML.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-6831876/v1/f5ef873b8fe68c634543e52c.png"},{"id":84776867,"identity":"7fa384ed-8f9d-41e9-a04e-a66da824e5d4","added_by":"auto","created_at":"2025-06-17 09:06:34","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":2829222,"visible":true,"origin":"","legend":"\u003cp\u003eDistal right femur medial and posterior fragmentation on initial radiographs (A and B, arrows) in a 5 month-old boy with no change on 14 days follow-up radiographs (C, and D, arrows). All radiologists reviewingseparately the initial and follow-up radiographs blinded to clinical history diagnosed metaphyseal variation with moderate to high confidence. Seven radiologists diagnosed metaphyseal fragmentation both in the initial and follow-up radiographs, and one radiologist as metaphyseal step off.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-6831876/v1/da1e96e7e049604821036b8f.png"},{"id":92884432,"identity":"08b89ccd-a7d0-4180-92d9-518708b3b835","added_by":"auto","created_at":"2025-10-06 16:12:50","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":6807839,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6831876/v1/994d96e5-2dd2-40ce-8ed7-10f1c8be5181.pdf"},{"id":84776865,"identity":"ca3b271e-0d52-4135-9eb4-c86c284326b2","added_by":"auto","created_at":"2025-06-17 09:06:34","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":23193,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eSupplementary Table 1.\u003c/strong\u003e Location of the radiographic signs within the metaphysis in the femurs\u003c/p\u003e","description":"","filename":"SupplementalTable1.docx","url":"https://assets-eu.researchsquare.com/files/rs-6831876/v1/cb230c39ab0536e7d87a6e91.docx"},{"id":84778219,"identity":"76fa5c5e-5528-43bd-be29-ddc604dd6d0d","added_by":"auto","created_at":"2025-06-17 09:14:34","extension":"docx","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":21896,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eSupplementary Table 2.\u003c/strong\u003e Location of the radiographic signs within the metaphysis in the tibias\u003c/p\u003e","description":"","filename":"Supplemetaltable2.docx","url":"https://assets-eu.researchsquare.com/files/rs-6831876/v1/5b12359299d843900d26463d.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Can metaphyseal variations in the distal femurs and proximal tibias be distinguished from classic metaphyseal lesions?","fulltext":[{"header":"Introduction","content":"\u003cp\u003eOne of the unique challenges in evaluating fractures in children is to differentiate between normal variation and fracture [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. This is especially critical when evaluating radiographs for child abuse. Missing fractures can have disastrous consequences and may lead to continued trauma to the child and handicap or even death [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. On the other hand, overdiagnosis of injuries suggestive of child abuse can lead to unnecessary emotional distress and the removal of the child from the home. It is therefore important for radiologists to recognize metaphyseal variations.\u003c/p\u003e \u003cp\u003eClassic metaphyseal lesion (CML) is a distinctive radiologic finding of either a corner fracture or bucket handle fracture that is highly specific for child abuse [\u003cspan additionalcitationids=\"CR4 CR5 CR6\" citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. However, certain normal metaphyseal variations in infancy should be carefully distinguished from the CML [\u003cspan additionalcitationids=\"CR9\" citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eAnatomically, the region of the growth plate that incorporates the groove and zone of Ranvier and the ring of Lacroix (all of which surround the physis and adjacent primary spongiosa) is called the periphysis [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. The appearance of the periphysis varies with the anatomical region and radiographic projection. Two principal radiographic patterns, step-off and spur, should be recognized as normal anatomical structures [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Another variation, metaphyseal fragmentation that is localized to the distal femur and proximal tibia, was found to be associated with physiological bowing in children older than 15 months of age [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. However, at our institution, we have also observed this variation in younger children with a low suspicion for nonaccidental trauma.\u003c/p\u003e \u003cp\u003eThis study aims to assess whether radiologists can accurately distinguish metaphyseal variations from CMLs.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003ePatient selection\u003c/h2\u003e \u003cp\u003e This study was approved by the institutional review board with a waiver of consent granted. This was a retrospective review of radiographic images of distal femurs and proximal tibias in children under two years of age who underwent a skeletal survey for suspected child abuse.\u003c/p\u003e \u003cp\u003eUsing our institution\u0026rsquo;s radiology information system (RIS), a pediatric radiologist with 27 years of experience post-fellowship, who did not participate in the imaging evaluation, retrospectively retrieved all skeletal surveys performed for evaluation of child abuse from 2007 to 2023. Two groups of patients were identified. The first group included children with a diagnosis of child abuse and reports of distal femur or proximal tibia CMLs. The second group included children that did not have a diagnosis of child abuse but who had reported distal femur or proximal tibial metaphyseal variation, with either no fractures or isolated accidental skull fracture, as isolated skull fracture has been found to be associated with a low risk for child abuse [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eFor the CML group, the RIS was searched using the keywords of \u0026ldquo;CML,\u0026rdquo; \u0026ldquo;classic metaphyseal lesion\u0026rdquo;, \u0026ldquo;corner fracture\u0026rdquo; or \u0026ldquo;bucket handle fracture\u0026rdquo;. For the metaphyseal variation group, the RIS was searched using the keywords of \u0026ldquo;irregularity,\u0026rdquo; \u0026ldquo;step off\u0026rdquo;, \u0026ldquo;beak\u0026rdquo;, \u0026ldquo;spur\u0026rdquo;, \u0026ldquo;fragmentation\u0026rdquo;, and \u0026ldquo;variation\u0026rdquo;.\u003c/p\u003e \u003cp\u003eAll reports were reviewed by the same pediatric radiologist, and only studies with reports referring to distal femur or proximal tibia in association with these keywords were selected.\u003c/p\u003e \u003cp\u003eTwo child abuse pediatricians who were not involved in image interpretation reviewed the electronic medical record (EMR). From the EMR, the following data were recorded: demographic information, history of prematurity, underlying medical diseases, the original radiologist interpretation of distal femur and proximal tibia findings, other injuries reported in the skeletal survey, and other imaging obtained to evaluate for abusive injuries.\u003c/p\u003e \u003cp\u003ePatients with metabolic bone disease and bone dysplasia were excluded.\u003c/p\u003e \u003cp\u003eThe reports of neuroimaging studies were reviewed for the presence of subdural hematoma, parenchymal contusion or tear, parenchymal bleeding, and hypoxic-ischemic changes. If there was no history or medical conditions to adequately explain them, the presence of at least one of these findings was considered a sign of high likelihood of abusive head trauma.\u003c/p\u003e \u003cp\u003eThe EMR was reviewed for the presence of the following physical injuries: bruising, burn injuries, other skin injuries, retinal bleeding, subconjunctival hemorrhage, and torn frenula.\u003c/p\u003e \u003cp\u003eThe child abuse pediatrician\u0026rsquo;s report was reviewed and categorized as positive, negative, or indeterminate for the diagnosis of physical abuse. Children with an indeterminate diagnosis of child abuse were excluded.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eRadiograph selection and preparation\u003c/h3\u003e\n\u003cp\u003eWe included initial and follow-up radiographs if available. Our routine skeletal surveys include anteroposterior (AP) and lateral radiographs of the long bones. From the skeletal surveys, the AP and lateral DICOM radiographs of the femurs and tibias were selected and anonymized. To minimize potential bias from other injuries visible on the radiographs, all images were trimmed by an experienced radiologic technologist under the supervision of a pediatric radiologist who was not involved in the image evaluation. Trimming was performed using the Santa DICOM Editor (Santsoft, Athens) to isolate the metaphysis of the distal femur, proximal tibia, or both, \u0026mdash;depending on which structures were included in the original radiograph.\u003c/p\u003e\n\u003ch3\u003eRadiograph review\u003c/h3\u003e\n\u003cp\u003eDICOM images were reviewed independently by eight radiologists using a diagnostic high-resolution monitor on the Synapse PACS system (FUJIFILM Medical Systems, Lexington, MA). All evaluations were performed in a randomized order and blinded to clinical information. To prevent paired comparison, initial and follow-up radiographs were separated and randomized, ensuring that radiologists could not view corresponding studies concurrently. Four reviewers were pediatric radiologists, and four were general emergency radiologists. Data collection and management were conducted using a secure, web-based application (REDCap; Vanderbilt University, Nashville, TN).\u003c/p\u003e \u003cp\u003eFor each metaphysis, the radiologist had to select one of the following options: normal, variation, CML, indeterminate. If normal, variation, or CML were selected, the radiologist had to assign a level of confidence: low, moderate, or high.\u003c/p\u003e \u003cp\u003eFor diagnosing CML, radiologists identified corner or bucket-handle fractures (any healing stage), corner deformity, subphyseal lucency, or metaphyseal irregularity with a rough metaphyseal\u0026ndash;physeal margin. Metaphyseal variation (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e) was diagnosed by the presence of step-off (acute discrete distal metaphyseal angulation), spur (longitudinal thin cortical projection beyond the metaphyseal edge), or fragmentation (metaphyseal corner fragmentation oriented along the shaft), with the specific location (medial, lateral, anterior, or posterior) noted. The location was described as either affecting the entire metaphysis or at least one of the following locations: medial, lateral, anterior, or posterior metaphysis.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eBefore the formal image review session, a pilot training session was conducted using 11 cases that did not meet the study\u0026rsquo;s inclusion criteria and were therefore excluded from the final cohort. These cases included six metaphyseal variations, four classic metaphyseal lesions (CMLs), and one indeterminate metaphyseal irregularity. The annotated cases were subsequently presented to the readers, to familiarize them with the spectrum of appearances and reinforce the classification criteria.\u003c/p\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eFisher\u0026rsquo;s exact tests and two-sample t-tests were used to compare the CML and metaphyseal variation groups for differences in patient characteristics. Agreement between radiologists was evaluated using crosstabs, percentage agreement, and kappa statistics. Kappa values of 0.01\u0026ndash;0.20 were considered as none to slight, 0.21\u0026ndash;0.40 as fair, 0.41\u0026ndash; 0.60 as moderate, 0.61\u0026ndash;0.80 as substantial, and 0.81\u0026ndash;1.00 as almost perfect agreement.\u003c/p\u003e \u003cp\u003eFor sensitivity and specificity calculations, a true positive diagnosis was defined as follows: a diagnosis of CML was considered correct for children in the CML group, and a diagnosis of metaphyseal variation was considered correct for children in the metaphyseal variation group. Generalized linear mixed models (GLMMs) were used to obtain combined estimates across all radiologists for accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). The GLMMs accounted for correlation among readings from multiple radiologists for each patient and for correlation among readings of all patients for each radiologist. GLMMs were then used to compare pediatric and general emergency radiologists for differences in the percentages of correct interpretations. GLMMs were also used to compare patients with metaphyseal variation and CML for differences in the frequencies of radiographic signs typically associated with metaphyseal variation (metaphyseal step off, beak, spur, fragmentation) and radiographic signs typically associated with CML (corner fracture, bucket-handle fracture, subphyseal lucency, metaphyseal irregularity).\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003ePatient population\u003c/h2\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e illustrates the flowchart of patient selection. A total of 54 children were initially reported to have (CMLs involving the distal femur or proximal tibia. Six children were excluded for the following reasons: presence of casting material on radiographs (n\u0026thinsp;=\u0026thinsp;3), treatment with topiramate (n\u0026thinsp;=\u0026thinsp;1), intraosseous needle evident on imaging (n\u0026thinsp;=\u0026thinsp;1), and lack of a diagnosis of child abuse (n\u0026thinsp;=\u0026thinsp;1). The final cohort included 48 children with radiology reports of CML, who underwent 78 skeletal surveys: 40 initial and 38 follow-up studies.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eSimilarly, 54 children had reports indicating metaphyseal variation in the distal femur or proximal tibia. Of these, 27 were excluded due to a definite (n\u0026thinsp;=\u0026thinsp;13) or indeterminate (n\u0026thinsp;=\u0026thinsp;8) diagnosis of child abuse, postmortem evaluation (n\u0026thinsp;=\u0026thinsp;2), absence of a lateral view (n\u0026thinsp;=\u0026thinsp;2), presence of subcutaneous emphysema (n\u0026thinsp;=\u0026thinsp;1), or limited clinical information (n\u0026thinsp;=\u0026thinsp;1). The final metaphyseal variation group included 27 children who underwent a total of 32 skeletal surveys: 20 initial and 12 follow-ups.\u003c/p\u003e \u003cp\u003eChildren in the CML group were significantly younger than those in the metaphyseal variation group (mean age 3 months; range: 1\u0026ndash;12 months vs. mean age 7 months; range: 1\u0026ndash;20 months; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.0005). The CML group comprised 30 males (62.5%) and 18 females (37.5%), while the metaphyseal variation group included 20 males (74.1%) and 7 females (25.9%), with no statistically significant sex distribution difference between groups (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.4445).\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eInjuries other than CML in the distal femurs and proximal tibias\u003c/h3\u003e\n\u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e summarizes the injuries in the study population. Among children in the CML group, 28 of 48 (58.3%) had other physical injuries, most commonly bruising (21/48, 43.8%), compared to only one child in the metaphyseal variation group, who had a torn frenulum.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eSummary of injuries found on physical examination and imaging in classic metaphyseal lesions (CMLs) and metaphyseal variations groups\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCML (n\u0026thinsp;=\u0026thinsp;48)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMV(n\u0026thinsp;=\u0026thinsp;27)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eP- values\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003ePhysical examination- any injury\u003c/span\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003e28 (58.3%)\u003c/span\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1 (3.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBruising\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e21 (43.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBurn injury\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 (2.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRetinal bleeding\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3 (6.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.549\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSubconjunctival H\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3 (6.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.549\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTorn frenulum\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5 (10.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1 (3.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.410\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003eHead trauma\u003c/span\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e11 (22.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3 (11.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.355\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSubdural\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10 (20.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3 (11.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.355\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eParenchymal contusion\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4 (8.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.290\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eParenchymal bleeding\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 (2.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAcute ischemia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3 (6.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.549\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVenous thrombosis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 (2.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003eFractures\u003c/span\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e45 (93.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8 (29.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSkull\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4 (8.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8 (29.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.023\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRibs\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e24 (50%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eUpper extremity\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e24 (50%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLower extremity\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e32 (66.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSpine\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 (2.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHands\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3 (6.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.549\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFeet\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 (2.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePelvis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 (2.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOthers\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7 (14.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.045\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eCML- classic metaphyseal lesions, MV- metaphyseal variation, PE- physical examination, H- hemorrhage\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eAbusive head trauma was diagnosed in 11 of 48 children (22.9%) in the CML group, with subdural hematoma being the most common finding (10/48, 20.8%). Three children in the metaphyseal variation group had small focal subdural hematomas\u0026mdash;two adjacent to a skull fracture and one associated with benign enlargement of the subarachnoid space.\u003c/p\u003e \u003cp\u003eFractures other than distal femur or proximal tibia CMLs were identified in 45 of 48 children (93.8%) with CMLs. The most common locations were the ribs (24/48, 50.0%), lower extremities (32/48, 66.7%), and upper extremities (24/48, 50.0%). Additionally, 24 of 48 children (50.0%) in the CML group had other CMLs, primarily in the lower (23/48, 47.9%) and upper extremities (7/48, 14.6%). In contrast, eight of 27 children (29.6%) in the metaphyseal variation group had skull fractures.\u003c/p\u003e\n\u003ch3\u003eDiagnostic accuracy of radiologists (moderate to high confidence)\u003c/h3\u003e\n\u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e summarizes diagnostic performance. Overall, radiologists demonstrated moderate diagnostic accuracy (76.1%) and sensitivity (70.2%), with high specificity (90.7%) and PPV (94.9%). The NPV was moderate at 55.2%.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eAccuracy of radiologists to diagnose classic metaphyseal lesions\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003eAll studies (n\u0026thinsp;=\u0026thinsp;110)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOutcome\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAll\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePed\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eGen\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAccuracy\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e76.1%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e80.4%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e71.7%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSensitivity\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e70.2%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e74.8%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e65.6%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.003\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSpecificity\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e90.7%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e93.5%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e87.5%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.162\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePPV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e94.9%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e96.4%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e93.2%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.200\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNPV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e55.2%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e61.2%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e49.4%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.002\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003ePPV\u0026thinsp;=\u0026thinsp;Positive predictive value, NPV-negative predictive value, Ped- pediatric radiologists, Gen- general emergency radiologists\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003ePediatric radiologists outperformed their general radiology counterparts, with significantly higher accuracy (80.4% vs. 71.7%, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.001), sensitivity (74.8% vs. 65.6%, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.003), and NPV (61.2% vs. 49.4%, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.002). No significant differences were found in specificity (93.5% vs. 87.5%, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.162) or PPV (94.9% vs. 96.4%, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.20).\u003c/p\u003e \u003cp\u003eDiagnostic performance was better at the initial visit compared to follow-up, with significantly higher accuracy, sensitivity, and NPV (all \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.002). However, specificity (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.22) and PPV did not differ between visits (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.559).\u003c/p\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eChange between initial and follow-up radiographs\u003c/h2\u003e \u003cp\u003eIn the CML group, 30 children had both initial and follow-up radiographs (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). Radiologists identified CML with moderate or high confidence in 115 of 154 studies (74.7%). On initial imaging, CMLs were diagnosed in 81 of 115 children (70.4%). An additional nine children were diagnosed as having CMLs on follow-up radiographs: four originally diagnosed as metaphyseal variation and five as normal.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eChanges in moderate and high confidence diagnoses from initial to follow-up reads by all eight radiologists in the classic metaphyseal lesions (CMLs) and metaphyseal variation groups\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"4\" nameend=\"c6\" namest=\"c3\"\u003e \u003cp\u003eFollow-up\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRadiologist\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eCML\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eMetaphyseal variation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eNormal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eInitial\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eCML Patients (n\u0026thinsp;=\u0026thinsp;154)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"3\" rowspan=\"4\"\u003e \u003cp\u003eAll\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCML\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e81 (70.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e17 (14.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e17 (14.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e115 (74.7%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMetaphyseal variation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4 (17.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e9 (39.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e10 (43.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e23 (14.9%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNormal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5 (31.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2 (12.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e9 (56.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e16 (10.4%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e90 (58.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e28 (18.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e36 (23.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e154\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"3\" rowspan=\"4\"\u003e \u003cp\u003ePediatric radiologists\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCML\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e47 (73.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e10 (15.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e7 (10.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e64 (81.0%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMetaphyseal variation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1 (10.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5 (50.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e4 (40.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e10 (12.7%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNormal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2 (40.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1 (20.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2 (40.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e5 (6.3%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e50 (63.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e16 (20.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e13 (16.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e79\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"3\" rowspan=\"4\"\u003e \u003cp\u003eGeneral radiologists\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCML\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e34 (66.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e7 (13.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e10 (19.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e51 (68.0%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMetaphyseal variation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3 (23.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4 (30.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e6 (46.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e13 (17.3%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNormal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3 (27.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1 (9.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e7 (63.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e11 (14.7%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e40 (53.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e12 (16.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e23 (30.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e75\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eMetaphyseal Variation Patients (n\u0026thinsp;=\u0026thinsp;25)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003eAll\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMetaphyseal variation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1 (4.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e22 (95.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e23 (92.0%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNormal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2 (100.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2 (8.0%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1 (4.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e24 (96.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e25\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"3\" rowspan=\"4\"\u003e \u003cp\u003ePediatric radiologists\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCML\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMetaphyseal variation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e14 (100.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e14 (100.0%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNormal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e14 (100.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"3\" rowspan=\"4\"\u003e \u003cp\u003eGeneral radiologists\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCML\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMetaphyseal variation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1 (11.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e8 (88.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e9 (81.8%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNormal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (\u0026lt;\u0026thinsp;0.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2 (100.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2 (18.2%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1 (9.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e10 (90.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e11\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eNotably, 34 of 115 children (29.4%) initially diagnosed with CML were reclassified on follow-up as having metaphyseal variation (n\u0026thinsp;=\u0026thinsp;17) or a normal metaphysis (n\u0026thinsp;=\u0026thinsp;17) (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eIn the metaphyseal variation group, five children had both initial and follow-up radiographs. Only one follow-up study was interpreted as CML, by a general radiologist. All others were interpreted as metaphyseal variation (n\u0026thinsp;=\u0026thinsp;22, Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e) or normal (n\u0026thinsp;=\u0026thinsp;2).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eLocation-based analysis of CMLs and metaphyseal variations (all confidence levels)\u003c/h2\u003e \u003cp\u003eTables S1 and S2 summarize the locations of metaphyseal variants and CMLs in the femurs and tibias. In the CML group, abnormalities were 1.4 times more common in the femur than in the tibia. CMLs were identified in 410 of 624 (65.7%) femurs and 286 of 624 (45.8%) tibias. In the metaphyseal variation group, abnormalities were four times more common in the femurs as compared with the tibias. Variants were identified in 169 of 256 (66.0%) femurs and 42 of 256 (16.4%) tibias.\u003c/p\u003e \u003cp\u003eAmong metaphyseal variants, fragmentation was most common: 259 of 356 femoral lesions (72.8%) and 69 of 83 tibial lesions (83.1%). This was followed by metaphyseal spurs, with 61 of 356 femurs (17.1%) and five of 83 tibias (6.0%), and meta (10.8%) physeal step-off, seen in 36 femurs (10.1%) and nine tibias (10.8%).\u003c/p\u003e \u003cp\u003eMetaphyseal fragmentation demonstrated a highly consistent distribution, occurring in the posterior and/or medial metaphyses in 257 of 259 femurs (99.2%) and 68 of 69 tibias (98.6%).\u003c/p\u003e \u003cp\u003eMetaphyseal spurs were most commonly identified in the anterior and/or lateral metaphyses in 50 of 61 femurs (82.0%). In contrast, the five spurs observed in the tibias were distributed across variable locations without a dominant pattern.\u003c/p\u003e \u003cp\u003eMetaphyseal step-offs, when confined to a single location, were equally distributed between the medial and lateral metaphyses of the femur (11 of 36 each; 30.6%). In four of 36 cases (11.1%), the step-off involved the posterior metaphysis in combination with either the medial or lateral side. One case demonstrated involvement of both medial and lateral metaphyses. In the tibia, step-offs were predominantly located in the medial metaphysis, observed in seven of nine cases (77.8%).\u003c/p\u003e \u003cp\u003eClassic metaphyseal lesion (CML) signs involved the entire metaphysis or at least three metaphyseal locations in 84 of 257 femurs (32.7%) and 80 of 177 tibias (45.2%). In contrast, metaphyseal variations involved the entire metaphysis or \u0026ge;\u0026thinsp;3 locations in only one of 356 femurs (0.3%) and one of 83 tibias (1.2%).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eConfidence comparison\u003c/h2\u003e \u003cp\u003eThere was no difference (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.113) in the proportion of low-confidence or indeterminate diagnoses between pediatric and general radiologists, occurring in 78 of 440 (17.7%) and 94 of 440 (21.4%) of the cases, respectively.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec14\" class=\"Section2\"\u003e \u003ch2\u003eAgreement between radiologists\u003c/h2\u003e \u003cp\u003eThe average agreement between radiologists was substantial (kappa\u0026thinsp;=\u0026thinsp;0.61), ranging from moderate to substantial (kappa of 0.41 to 0.78) between radiologist pairs (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). The most experienced pediatric radiologists demonstrated the highest agreement (kappa\u0026thinsp;=\u0026thinsp;0.78).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eAgreement between radiologists on diagnosis of classic metaphyseal lesions and metaphyseal variations\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c5\" namest=\"c3\"\u003e \u003cp\u003eKappa (95% CI)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePair\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eAll\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eInitial\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eFollow-up\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"6\" rowspan=\"7\"\u003e \u003cp\u003ePediatric\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 and 2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.78\u003c/p\u003e \u003cp\u003e(0.65 to 0.91)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.79\u003c/p\u003e \u003cp\u003e(0.62 to 0.97)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.75\u003c/p\u003e \u003cp\u003e(0.55 to 0.95)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 and 3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.56 (0.38 to 0.73)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.55 (0.31 to 0.78)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.54\u003c/p\u003e \u003cp\u003e(0.27 to 0.80)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 and 4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.57\u003c/p\u003e \u003cp\u003e(0.40 to 0.74)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.45\u003c/p\u003e \u003cp\u003e(0.22 to 0.69)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.67\u003c/p\u003e \u003cp\u003e(0.44 to 0.91)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2 and 3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.65\u003c/p\u003e \u003cp\u003e(0.51 to 0.80)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.72\u003c/p\u003e \u003cp\u003e(0.53 to 0.91)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.57\u003c/p\u003e \u003cp\u003e(0.35 to 0.79)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2 and 4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.60\u003c/p\u003e \u003cp\u003e(0.46 to 0.74)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.60\u003c/p\u003e \u003cp\u003e(0.41 to 0.80)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.58\u003c/p\u003e \u003cp\u003e(0.38 to 0.79)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3 and 4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.51\u003c/p\u003e \u003cp\u003e(0.36 to 0.66)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.44\u003c/p\u003e \u003cp\u003e(0.23 to 0.66)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.56\u003c/p\u003e \u003cp\u003e(0.35 to 0.77)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAverage\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.61\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.59\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.61\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"6\" rowspan=\"7\"\u003e \u003cp\u003eGeneral\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 and 2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.49\u003c/p\u003e \u003cp\u003e(0.35 to 0.64)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.48\u003c/p\u003e \u003cp\u003e(0.29 to 0.68)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.49\u003c/p\u003e \u003cp\u003e(0.27 to 0.70)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 and 3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.48\u003c/p\u003e \u003cp\u003e(0.30 to 0.66)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.41\u003c/p\u003e \u003cp\u003e(0.17 to 0.65)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.53\u003c/p\u003e \u003cp\u003e(0.27 to 0.79)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 and 4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.41\u003c/p\u003e \u003cp\u003e(0.26 to 0.55)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.41\u003c/p\u003e \u003cp\u003e(0.22 to 0.60)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.39\u003c/p\u003e \u003cp\u003e(0.16 to 0.61)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2 and 3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.63\u003c/p\u003e \u003cp\u003e(0.45 to 0.80)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.54\u003c/p\u003e \u003cp\u003e(0.27 to 0.81)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.66\u003c/p\u003e \u003cp\u003e(0.41 to 0.91)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2 and 4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.70\u003c/p\u003e \u003cp\u003e(0.56 to 0.84)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.57\u003c/p\u003e \u003cp\u003e(0.35 to 0.79)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.81\u003c/p\u003e \u003cp\u003e(0.63 to 0.98)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3 and 4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.61\u003c/p\u003e \u003cp\u003e(0.43 to 0.80)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.62\u003c/p\u003e \u003cp\u003e(0.36 to 0.87)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.59\u003c/p\u003e \u003cp\u003e(0.31 to 0.86)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAverage\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.55\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.58\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAll\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAverage\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.61\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.59\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.59\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eOur study demonstrates that CMLs can be distinguished from metaphyseal variations with high specificity and positive predictive values, and that metaphyseal fragmentation is the most common variation, predominantly occurring in the distal femur.\u003c/p\u003e \u003cp\u003eThere are few studies on metaphyseal variations that can mimic CMLs. In 408 children under two years\u0026thinsp;=\u0026thinsp;old who were admitted to the emergency department for suspected trauma, Eide et al. reported an incidence of 16.3% for metaphyseal collar and 8.6% for irregular metaphysis variations [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Kleinman et al. found step-off variation in 3% of the distal femurs in a study of 78 postmortem examinations in patients with sudden infant death syndrome [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe challenge in differentiating metaphyseal variations from CMLs has been highlighted in a few studies. Karmazyn et al. reported that following a double read of outside studies of skeletal surveys, four of 19 CMLs diagnosed by outside radiologists were read as metaphyseal variants by a pediatric radiologist [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Kleinman et al. reported that in one child metaphyseal fragmentation was misinterpreted as a CML, prompting a child abuse evaluation including skeletal survey [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. A similar misdiagnosis was documented in another case report [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eOur study is the first to evaluate the accuracy of radiologists in differentiating between CMLs and metaphyseal variations. Our study was focused on the knees, as from our experience this is the most common location where metaphyseal variations are misinterpreted as CMLs. This is also the most common location of CMLs [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e].\u003c/p\u003e \u003cp\u003e On average, the agreement between radiologists in our study was substantial (kappa\u0026thinsp;=\u0026thinsp;0.61) with no significant difference in the rate of low confidence diagnosis between pediatric and general radiologists. The most experienced pair of pediatric radiologists had the highest agreement (kappa\u0026thinsp;=\u0026thinsp;0.78).\u003c/p\u003e \u003cp\u003eBoth groups of radiologists had high specificity (90.7%) and PPV (94.9%) with no significant difference between them. These findings suggest that when radiologists diagnose CMLs, there is a high probability that the diagnosis is correct. However, there was moderate sensitivity (70.2%) and NPV (55.2%). The pediatric radiologists performed significantly better than the general radiologists in both sensitivity and NPV, suggesting they may be better at detection of CMLs.\u003c/p\u003e \u003cp\u003eDiagnostic performance was significantly better at the initial visit compared to the follow-up, with higher accuracy, sensitivity, and NPV, whereas specificity and PPV did not show a significant difference. This suggests that the ability to reliably diagnose CML was better on the initial compared to follow-up radiographs. This reduced accuracy at follow-ups can be explained by healing and normalization of the CML on follow-up radiographs [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eMetaphyseal fragmentation was the most common metaphyseal variation that was identified. Compared with the study of Kleinman et al. [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e] our study shows that this variation also occurs in infants. In contrast to signs related to CMLs, which in about a third of femurs and tibias involve the entire metaphysis or at least three metaphyseal locations, metaphyseal fragmentation involved only the medial and/or posterior metaphyses in 244 of 259 (94.2%) femurs and in 68 of 69 (98.6%) tibias.\u003c/p\u003e \u003cp\u003eIn the CML group, four children initially diagnosed with metaphyseal variation and five initially diagnosed with normal metaphyses were diagnosed on follow-up radiographs as CML. This confirms the importance of follow-up radiographs. In a study by Kleinman et al., most new fractures identified on follow-up skeletal survey involved CMLs and ribs [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. In the metaphyseal variation group, only one general radiologist diagnosed CML on follow-up radiographs, suggesting that metaphyseal variations diagnosed on initial radiographs are unlikely to be diagnosed as a CML on follow-up skeletal survey.\u003c/p\u003e \u003cp\u003eCML is considered highly specific for child abuse. Therefore, its presence should raise suspicion for abuse, even if it is the only detected lesion [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. However, CMLs rarely occur in isolation without other fractures [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. Notably, most children in the metaphyseal variation group in our study had no other fractures, and about a third had only a skull fracture. Radiologists should be especially prudent when metaphyseal changes appear in isolation, as misinterpreting metaphyseal variations as CMLs could significantly impact both medical and child protection management.\u003c/p\u003e \u003cp\u003eOur study has several limitations. There was no gold standard for the diagnosis of CML and metaphyseal variations. Instead, cases were diagnosed based on clinical and imaging findings. There was as small sample of follow-up radiographs, with only five children in the metaphyseal variation group that had follow-up radiographs, potentially limiting our assessment of change in radiologists\u0026rsquo; interpretation between initial and follow-up radiographs. In addition, radiologists were blinded to prior radiographs and ultrasound studies that are occasionally used in challenging cases, which could result in the incorrect diagnosis of healing CMLs as metaphyseal variations or as normal on follow-up radiographs.\u003c/p\u003e \u003cp\u003eIn summary, we found substantial agreement between radiologists in the evaluation of CMLs and metaphyseal variations of the distal femur and proximal tibia. Radiologists had high specificity and positive predictive value in the diagnosis of CMLs, and pediatric radiologists performed significantly better than the general radiologists in both sensitivity and negative predictive value, suggesting they may be better at detection of CMLs.\u003c/p\u003e \u003cp\u003eMetaphyseal fragmentation was the most common type of metaphyseal variation, predominantly located in the medial and posterior metaphysis of the distal femur. Importantly, metaphyseal variations identified on initial radiographs were unlikely to be later diagnosed as CMLs on follow-up imaging.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eThis study was approved by the Institutional Review Board.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of interest:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e\n\u003ch2\u003eFunding:\u003c/h2\u003e\n\u003cp\u003eThere was no funding for the study.\u003c/p\u003e\n\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\n\u003cp\u003eBoaz Karmazyn conceptualized and designed the study and drafted the initial manuscript.Christopher L. Newman performed image review and revised the study.Megan B Marine performed images review. Mathew R Wanner performed images review. Jared R Shield performed images review. Scott D Steenburg performed images review. Alexander G Boutselis performed images review. Jordan H Cuskaden performed images review. Eric D Westin performed images review. Marrisa Luma M.D, assisted with clinical data collection.George J Eckert assisted in the statistical analysis and revised the study.Greg S Jennings assisted in conceptualizing and designing the study and critically revised the study.Ralph A Hicks assisted in conceptualizing and designing the study, assisted with clinical data analysis.All authors reviewed and approved the final manuscript.\u003c/p\u003e\n\u003ch2\u003eAcknowledgement\u003c/h2\u003e\n\u003cp\u003eWe thank Wendy Territo for trimming the radiographs of the femurs and tibias\u003c/p\u003e\n\u003ch2\u003eData Availability:\u003c/h2\u003e\n\u003cp\u003eThe data that support the findings of this study are available from the corresponding author upon reasonable request. Due to the nature of clinical data and patient privacy regulations, the data are not publicly available.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eTougas C, Brimmo O (2022) Common and Consequential Fractures That Should Not Be Missed in Children. Pediatr Ann 51:e357\u0026ndash;e363\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eOral R, Yagmur F, Nashelsky M, Turkmen M, Kirby P (2008) Fatal abusive head trauma cases: consequence of medical staff missing milder forms of physical abuse. Pediatr Emerg Care 24:816\u0026ndash;821\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFlaherty EG, Perez-Rossello JM, Levine MA, Hennrikus WL (2014) Evaluating children with fractures for child physical abuse. Pediatrics 133:e477\u0026ndash;489\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKleinman PK, Perez-Rossello JM, Newton AW, Feldman HA, Kleinman PL (2011) Prevalence of the classic metaphyseal lesion in infants at low versus high risk for abuse. AJR Am J Roentgenol 197:1005\u0026ndash;1008\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eEide P, Djuve A, Myklebust R, Forseth KF, Nottveit A, Brudvik C, Rosendahl K (2019) Prevalence of metaphyseal injury and its mimickers in otherwise healthy children under two years of age. Pediatr Radiol 49:1051\u0026ndash;1055\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAdamsbaum C, De Boissieu P, Teglas JP, Rey-Salmon C (2019) Classic Metaphyseal Lesions among Victims of Abuse. J Pediatr 209:154\u0026ndash;159e152\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eThackeray JD, Wannemacher J, Adler BH, Lindberg DM (2016) The classic metaphyseal lesion and traumatic injury. Pediatr Radiol 46:1128\u0026ndash;1133\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eQuigley AJ, Stafrace S (2014) Skeletal survey normal variants, artefacts and commonly misinterpreted findings not to be confused with non-accidental injury. Pediatr Radiol 44:82\u0026ndash;93 quiz 79\u0026ndash;81\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKleinman PK, Sarwar ZU, Newton AW, Perez-Rossello JM, Rebello G, Herliczek TW (2009) Metaphyseal fragmentation with physiologic bowing: a finding not to be confused with the classic metaphyseal lesion. AJR Am J Roentgenol 192:1266\u0026ndash;1268\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKleinman PK, Belanger PL, Karellas A, Spevak MR (1991) Normal metaphyseal radiologic variants not to be confused with findings of infant abuse. AJR Am J Roentgenol 156:781\u0026ndash;783\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eOestreich AE, Ahmad BS (1992) The periphysis and its effect on the metaphysis: I. Definition and normal radiographic pattern. Skelet Radiol 21:283\u0026ndash;286\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLeventhal JM, Martin KD, Asnes AG (2010) Fractures and traumatic brain injuries: abuse versus accidents in a US database of hospitalized children. Pediatrics 126:e104\u0026ndash;115\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eEide P, Djuve \u0026Aring;, Myklebust R, Forseth KF, N\u0026oslash;ttveit A, Brudvik C, Rosendahl K (2019) Prevalence of metaphyseal injury and its mimickers in otherwise healthy children under two years of age. Pediatr Radiol 49:1051\u0026ndash;1055\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKarmazyn B, Wanner MR, Marine MB, Tilmans L, Jennings SG, Hibbard RA (2019) The added value of a second read by pediatric radiologists for outside skeletal surveys. Pediatr Radiol 49:203\u0026ndash;209\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNorrell K, Hennrikus W (2017) The Risk of Assuming Abuse in an Infant with an Isolated Metaphyseal Lesion: A Case Report. JBJS Case Connect 7:e69\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBarber I, Perez-Rossello JM, Wilson CR, Kleinman PK (2015) The yield of high-detail radiographic skeletal surveys in suspected infant abuse. Pediatr Radiol 45:69\u0026ndash;80\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKarmazyn B, Marine MB, Wanner MR, Sağlam D, Jennings SG, Hibbard RA (2020) Establishing signs for acute and healing phases of distal tibial classic metaphyseal lesions. Pediatr Radiol 50:715\u0026ndash;725\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKleinman PK, Nimkin K, Spevak MR, Rayder SM, Madansky DL, Shelton YA et al (1996) Follow-up skeletal surveys in suspected child abuse. AJR Am J Roentgenol 167:893\u0026ndash;896\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"pediatric-radiology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"prad","sideBox":"Learn more about [Pediatric Radiology](http://link.springer.com/journal/247)","snPcode":"247","submissionUrl":"https://submission.nature.com/new-submission/247/3","title":"Pediatric Radiology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Classic metaphyseal lesion, Infant, Metaphyseal variation, Skeletal survey","lastPublishedDoi":"10.21203/rs.3.rs-6831876/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6831876/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground: \u003c/strong\u003eClassic metaphyseal lesions (CMLs) are considered specific for child abuse, but the reliability of radiologists in distinguishing CMLs from metaphyseal variations is unclear.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eObjective: \u003c/strong\u003eTo evaluate whether radiologists can differentiate between CMLs and metaphyseal variations in the knees.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMaterials and Methods: \u003c/strong\u003eWe performed a\u003cstrong\u003e \u003c/strong\u003eretrospective review of distal femur and proximal tibia radiographs in children under two years of age who underwent skeletal surveys for suspected child abuse. The CML group included children diagnosed with abuse and reported CMLs. The metaphyseal variation group included children not diagnosed with abuse, with reported metaphyseal variations and either no fractures or an isolated skull fracture. Radiographs were trimmed to exclude other injuries. Four pediatric and four general radiologists reviewed anonymized studies and categorized each case as CML, metaphyseal variation, normal, or indeterminate, with confidence levels (high, moderate, low). We analyzed diagnoses with moderate or high confidence. Interobserver agreement was assessed using kappa statistics.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults: \u003c/strong\u003eThere were 48 children with CMLs (40 initial, 38 follow-up) and 27 with metaphyseal variations (20 initial, 12 follow-up). Metaphyseal fragmentation was the most common variation, identified in 259 of 356 femurs (72.8%) and 69 of 83 tibias (83.1%). Fragmentations were most frequently located in the posterior or medial metaphysis, or both, in 257 of 259 femurs (99.2%) (257/259) and 68 of 69 tibias (98.6%).\u003c/p\u003e\n\u003cp\u003eIn the CML group, 34 of 115 initial CML diagnoses (29.4%) were read on follow-up as either metaphyseal variation (n=17) or normal (n=17). In contrast, in the metaphyseal variation group, only one follow-up case was diagnosed as a CML; the remainder were diagnosed as metaphyseal variation (n=22) or normal (n=2).\u003c/p\u003e\n\u003cp\u003eDiagnostic performance for CML demonstrated high specificity (90.7%) and positive predictive value (94.9%), with moderate accuracy (76.1%), sensitivity (70.2%), and negative predictive value (55.2%). Interobserver agreement was substantial, with a mean kappa of 0.61.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion\u003c/strong\u003e: Radiologists demonstrated substantial agreement and high specificity in distinguishing CMLs from metaphyseal variations. Metaphyseal fragmentation was the most common variation and was uncommonly diagnosed as CML on follow-up.\u003c/p\u003e","manuscriptTitle":"Can metaphyseal variations in the distal femurs and proximal tibias be distinguished from classic metaphyseal lesions?","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-06-17 09:06:29","doi":"10.21203/rs.3.rs-6831876/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-07-02T12:31:14+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-06-24T21:48:12+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-06-24T15:04:47+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"270977212211252609854114901725204442200","date":"2025-06-17T14:15:34+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"282185723755259782446591289477105232560","date":"2025-06-14T12:38:05+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-06-13T18:29:19+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"12358476802586322518568671756631709730","date":"2025-06-12T11:37:08+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"211802544879014478368491335304641180263","date":"2025-06-12T02:45:51+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-06-12T01:38:33+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-06-09T08:43:28+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-06-09T08:42:56+00:00","index":"","fulltext":""},{"type":"submitted","content":"Pediatric Radiology","date":"2025-06-05T20:09:23+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"pediatric-radiology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"prad","sideBox":"Learn more about [Pediatric Radiology](http://link.springer.com/journal/247)","snPcode":"247","submissionUrl":"https://submission.nature.com/new-submission/247/3","title":"Pediatric Radiology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"f09c8dad-19c6-44c2-9489-6dce915b281a","owner":[],"postedDate":"June 17th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-10-06T16:09:09+00:00","versionOfRecord":{"articleIdentity":"rs-6831876","link":"https://doi.org/10.1007/s00247-025-06398-w","journal":{"identity":"pediatric-radiology","isVorOnly":false,"title":"Pediatric Radiology"},"publishedOn":"2025-10-01 15:57:37","publishedOnDateReadable":"October 1st, 2025"},"versionCreatedAt":"2025-06-17 09:06:29","video":"","vorDoi":"10.1007/s00247-025-06398-w","vorDoiUrl":"https://doi.org/10.1007/s00247-025-06398-w","workflowStages":[]},"version":"v1","identity":"rs-6831876","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6831876","identity":"rs-6831876","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}