Low bone mineral density is not a predictive factor for subchondral insufficiency fracture of the knee, based on the analysis of QCT studies

Low bone mineral density is not a predictive factor for subchondral insufficiency fracture of the knee, based on the analysis of QCT studies | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Low bone mineral density is not a predictive factor for subchondral insufficiency fracture of the knee, based on the analysis of QCT studies Zijie Zhang, Changyu Huang, Xinyu Fang, Yang Chen, Wenming Zhang, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6245969/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Purpose The association between subchondral insufficiency fracture of knee (SIFK) and potential lower bone mineral density (BMD) were not clear and multifactorial. We tried to investigate their relevance by using the phantom-less quantitative computed tomography (QCT). Methods We collected bone mineral density (BMD) measurements from 32 cases diagnosed with SIFK and 28 control cases with osteoarthritis of the knee(KOA). All SIFK cases were gathered within two months of symptom onset and met the diagnostic criteria for magnetic resonance imaging. BMD measurements were conducted at the femoral neck and knee compartments. The medial-to-lateral (M-L) BMD ratios for the femoral and tibial medial compartments were compared between the two groups. Results The mean BMD values for the femoral neck and medial femoral regions showed no statistically significant difference between the SIFK cases and the KOA group. However, the mean tibial medial-to-lateral (M-L) ratios were statistically higher in the KOA group compared to those in the SIFK group, while the femoral M-L ratios remained statistically consistent between the two groups. The mean BMD in the osteonecrotic area was measured at 63.9 mg/cm³, with all instances located within the femoral condyle. Conclusion Our findings do not support the hypothesis that SIFK are based on low bone mineral density, which was regard as a predictive factor in previous studies. Biological sciences/Biological techniques Biological sciences/Computational biology and bioinformatics subchondral insufficiency fracture of knee bone mineral density quantitative computed tomography Introduction Subchondral insufficiency fracture of the knee (SIFK) is characterized as damage resulting from repetitive mechanical stress on the joints [ 10 ]. In the past researches, stress fracture usually occurs in our weight-bearing joints or bones which is referred to insufficiency fractures[ 12 ]. As we all know, Ahlbäck et al. first described the disease “spontaneous osteonecrosis of the knee” (SONK) in 1968[ 23 ]. With the deepening of researches, it is gradually accepted that SONK is the terminal stage manifestation of SIFK[ 4 ]. Therefore, nowadays SIFK and SONK are both applied to describe the stress fracture of the knee joints. Based on the definition of insufficiency fracture, reduced bone mineral density(BMD) was used to be a potential risk for SIFK. Zanetti et al. found that there were about two thirds of the patients who suffered from the osteoporosis or osteopenia in a cohort of 32 samples[ 27 ]. Another research reported that low BMD occurred in lateral femoral, tibial condyle and femoral neck in SONK groups compared with knee osteoarthritis (KOA) groups in a cohort of 52 female patients[ 1 ]. However, it was reported that only 16% (5/32) of SIFK patients were diagnosed as osteoporosis, proving that reduced BMD might not consider as a potential risk for SIFK[ 18 ]. To the best of our knowledge, the relationship between SIFK and low BMD remains controversial, and no study has yet established a definitive association between BMD at a specific threshold and the occurrence of SIFK. In addition, most of the research were used dual-energy X-ray absorptiometry. We would like to applied a novel automatic phantom-less QCT BMD Analysis in our research to detected the association between the low BMD and SIFK. Results Demographic characteristics Two authors (ZJ and ZD) assessed the area of 40 femoral osteonecrosis in the pre-experimental group, achieving an inter-observer intraclass correlation coefficient of 0.912. Additionally, these authors classified the SIFK lesions, obtaining a kappa coefficient of 0.87. We identified 32 patients in the SIFK group and 28 patients in the OA group, with all participants being counted for unilateral knees only. The patients’ characteristics were listed in the Table 2, in which no significant difference was found according to the age, BMI. In the SIFK group, the Kellgren and Lawrence grades included grade two in five knees, grade three in five knees, and grades three-four in 25 knees. In the KOA group, there were five knees with grade two and 23 knees with grades three-four. The Kushino radiographic stages of SIFK at the time of diagnosis were stage one in two knees, stage two in eight knees, and stages three-four in 22 knees (Table 3). Differences in BMD between the two groups The mean femoral neck BMD showed no significant difference between the SIFK and KOA groups according to traditional DXA methods (p = 0.241). However, we observed that some patients in both groups exhibited low BMDs at the femoral neck. In contrast, there was no statistically significant difference in the Sub-BMD of the medial femoral condyle between the two groups, with values of 263.87 g/cm³ and 256.99 g/cm³, respectively. A similar outcome was noted for the Mid-BMD of the medial femoral condyle, which measured 184.34 g/cm³ in the SIFK group and 166.30 g/cm³ in the KOA group. The mean medial and lateral BMDs of the tibial condyle were not statistically significant between the SIFK and KOA groups (p = 0.055 and p = 0.114, respectively). Nevertheless, the mean tibial M-L ratios were significantly higher in the KOA group compared to the SIFK group. Additionally, there was no difference in the mean femoral ratios where all the bone necrosis occurred between the SIFK and KOA groups (Table 4). The mean BMD of the osteonecrosis area in the SIFK group was 63.9 g/cm³, which would be classified as osteoporosis according to ACR guidelines. Discussion We observed that the BMD of the femoral neck, subchondral and mid-epiphyseal regions of the medial femoral condyle, as well as the medial tibial condyle, exhibited no statistically significant differences between the SIFK and KOA patients. The only notable finding was that the tibial M-L ratio was significantly higher in the KOA patients compared to those with SIFK, whereas no differences were observed in the femoral M-L ratios at the sites of osteonecrosis. Our results do not support the theory that subchondral insufficiency fractures due to low BMD are a contributing factor in the onset of SIFK. SIFK is a type of insufficiency fracture, characterized as a form of stress fracture that tends to occur in the weight-bearing joints of the lower legs[13]. According to this definition, low bone mineral density (BMD) has traditionally been regarded as a risk factor for SIFK. Several studies have reported a link between low BMD and SIFK[2, 17, 20].For instance, Akamatsu et al. compared the BMD of 26 women with SONK to that of 26 women with medial knee osteoarthritis (OA) using DXA methods. They concluded that some elderly women may experience microfractures in the femoral condyles due to the rapid progression of low BMD[2]. However, in a more recent study, Nelson et al. found that only 16% (5 out of 32) of SIFK patients were classified as having osteoporosis, suggesting that low BMD may not be the primary risk factor for SIFK[19]. As far as we know, the relationship between low BMD and SIFK remains a topic of controversy. In our study, approximately half of the 60 patients had low bone density in the femoral neck measured by conventional DXA technology, and the majority of SIFK patients were elderly females which is similar to previous results[2]. By using the Automatic Phantom-Less QCT, we also found located low BMD in the medial femoral condyle and medial tibial in both the SIFK and OA groups. However, the proportion of low BMD patients was limited which was 3/32 (the SIFK group) and 4/28 (the OA group), respectively. This reflects that low BMD might not be a predictive factor for the occurrence of SIFK or OA. Additionally, several studies have identified an association between knee OA and SIFK[8, 20]. Allam et al. reported that the extent of chondrosis was correlated with the severity of SIFK[5]. Similarly, Plett et al. found that 75.7% (53 out of 70) of SIFK patients exhibited overlying full-thickness cartilage loss, and 94.1% (64 out of 68) had ipsilateral meniscal injuries[20]. These findings suggest that meniscal injuries may be linked to the development of both SIFK and OA. An abnormal M-L ratio in patients with KOA or SIFK is linked to an increase in varus deformity, bone marrow lesions, osteophyte formation, joint space narrowing, and subchondral sclerosis.[2, 14, 28]. However, the statistically consistent femoral M-L ratio in two groups in our study was not matched to the previous findings[2]. Most of the previous studies were not calculated the femoral condyle BMD, but using femoral neck or lumbar spine ones. Recent studies have shown that quantitative computed tomography (QCT) is a more sensitive method for diagnosing osteoporosis and predicting fractures than dual-energy X-ray absorptiometry (DXA).[6]. Above all, we speculate these results might prove the potential association between OA and SIFK, that is the SIFK patients had suffered from OA before the onset of osteonecrosis. SIFK is reported to be more command in female patients over 50 years old, and most were found at the weight-bearing area[20, 26]. Due to age-related changes in estrogen levels, low bone mineral density (BMD) has been regarded as a contributing factor in the higher prevalence of SIFK among older women. The traditional DXA method evaluates the systematic BMD of patients, while the measurements of local ones are relatively weak. The principle of QCT is to measure BMD within the selected volume, which has certain advantages[6]. SIFK has been reported to be associated with blood supply to the femoral condyles, mechanical overload, or mechanical axis deviation[7, 22, 25]. The area of osteonecrosis resulting from subchondral fractures has been pathologically shown to comprise a mixture of a series of pathophysiological processes, occurring in varying proportions[3]. According to consensus definition, osteoporosis only represents changes in bone density during fracture healing and does not reflect the presence of local bone mass before the fracture. Additionally, a previous report found that the area affected by SIFK may extend over a substantial portion of the involved condyle[9]. There were several limitations in our study. First, as the inherent flaws in retrospective research, the measurement of bone density and CT scan in our center was not tested as a routine item for a long time, resulting in the loss of a large number of reliable cases. In addition, due to the large time span of inclusion, there are 3 types of devices used for CT image acquisition (Table 1). Previous literature has reported that there may be bias because of the images obtained with different CT scanning parameters[24]. We believe that SIFK were discovered due to the bone marrow edema reaction after local trabecular fracture caused by excessive stress load and pre-existing OA, not by the low BMD as a predictive factor. Future investigations should consider on the association between the early stage of subchondral fracture and local BMD. Methods Patient population Patients diagnosed with SONK or SIFK admitted to the two centers from 2017 to 2023 were retrospectively analyzed (the SIFK group), which was based on the criteria of SONK and SIFK defined by Ahlbäck et al. and Lotke et al[ 16 ]. All patients had no medical record of corticosteroid intake, alcohol abuse, knee trauma or intra-articular injection during the period of joint pain. Due to the conditions required by QCT testing, cases in which one mm or two mm thin slice images were not taken were excluded from our study. We enrolled 26 patients with knee osteoarthritis (the KOA group) as the control group and recorded their femoral neck bone mineral density (BMD) using a Lunar Prodigy scanner (GE, Madison, WI, USA). Initially, we obtained relevant data, including Knee Society Scores, knee function scores, and pain scores. Our study received approval from the institutional review board (protocol number: MRCTA, ECFAH of FMU [2020]289). Informed consent was obtained from all patients participating in the study. We confirmed that all research was performed in accordance with the Declaration of Helsinki. Radiography All patients in two goups need to collect their standing anteroposterior and lateral knee radiological films. The radiograph was also applied to distinguish the grade of disease in the SIFK group, which was classified into four stages[ 15 ]. Magnetic Resonance Imaging Magnetic resonance imaging (MRI) was the regular examination in SIFK group. The diagnostic criteria for SIFK or SONK on MRI included a distinct decrease in intensity on the T1-weighted image, along with a corresponding decrease in intensity surrounded by a high-intensity area–indicating bone marrow swelling–on the T2-weighted and fat-suppressed images of the inner femoral condyle. Computed Tomography Computed Tomography (CT) images were captured by three different devices in the center, GE-revolution CT and Philips IQon CT. The parameters of the CT machine are described in the Table 1 . All patients took bilateral knee CT 3D reconstruction examinations, and uploaded thin-slice images with a thickness of one mm for follow-up testing. Automatic Phantom-Less QCT BMD Analysis We employed an automatic phantom-less QCT software, FRAX BMD 1.0 (Bo-Zhi Biotech, Shenzhen, China), suited for localized BMD assessments, encompassing both cancellous and cortical bone. This innovative PL-QCT features an automatic capability to identify vertebrae, hip, fat, and muscle regions of interest (ROI) while ensuring precise calibration of BMD. A comprehensive overview of the development process of this phantom-less QCT technology can be found in prior research[ 24 , 29 ]. The CT values from the fat and muscle regions of interest (ROI) have been utilized to adjust the BMD results. As the definition of anatomic coordinate systems in previous study[ 21 ], we detected the number of BMD in weight-bearing area of the regions of interest (ROI), including subchondral (Sub) and mid-epiphyseal (Mid). Both sides of femur and tibia were measured. Regarding of osteochondral defects, we measured BMD of ROI described in the methodology, as well as the approximate density within the defect range based on CT and MRI images. The ratios of medial condyle BMD to lateral one (M-L ratios) in both the femur and tibia were computed as comparative parameters for the two compartments. Patients were classified based on the WHO criteria (1994). A T-score greater than − 1 was classified as normal, a T-score between − 1 and − 2.49 was designated as osteopenia, and a T-score of − 2.5 or lower was categorized as osteoporosis. Additionally, osteopenia and osteoporosis were grouped together under the term low BMD. According to the guidelines of the American College of Radiology (ACR) in 2008 on practical parameters for BMD in musculoskeletal QCT and their 2013 revision, BMD value > 120 mg/cm 3 indicates normal ones, 80 ~ 120 mg/cm 3 indicates osteopenia, and < 80mg/cm 3 indicates osteoporosis[ 11 , 30 ]. Statistics Data were presented as the mean accompanied by a 95% confidence interval (CI). The Shapiro-Wilk test was employed to assess the normality of the data. Differences between the groups were evaluated using Student’s t-test for continuous variables that followed a normal distribution, whereas the Mann-Whitney test was applied when the data did not meet this criterion. Statistical analyses were conducted using SPSS software version 17. A p-value of less than 0.05 was deemed significant. Declarations Acknowledgements The authors thank all participants that agreed to participate in this study. Author Contributions All authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by Zijie Zhang, Zida Huang and Changyu Huang. The first draft of the manuscript was written by Zijie Zhang and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript. Data Availability The data that support the findings of this study are available from corresponding author, but restrictions apply to the availability of these data, which were used under licence for the current study and so are not publicly available. The data are, however, available from the authors upon reasonable request. Competing interest The authors have no relevant financial or non-financial interests to disclose. Ethic Approval Our study received approval from the institutional review board (protocol number: MRCTA, ECFAH of FMU [2020]289). Informed consent was obtained from all patients participating in the study. References Akamatsu, Y., Mitsugi, N., Hayashi, T., Kobayashi, H. & Saito, T. Low bone mineral density is associated with the onset of spontaneous osteonecrosis of the knee. Acta Orthop. 83 (3), 249–255 (2012). Akamatsu, Y., Mitsugi, N., Hayashi, T., Kobayashi, H. & Saito, T. Low bone mineral density is associated with the onset of spontaneous osteonecrosis of the knee. Acta Orthop. 83 (3), 249–255 (2012). Akhavan, S., Martinkovich, S. C., Kasik, C. & DeMeo, P. J. Bone Marrow Edema, Clinical Significance, and Treatment Options: A Review. J. Am. Acad. Orthop. Surg. 28 (20), e888–e899 (2020). Allam, E. et al. Subchondral insufficiency fracture of the knee: unicompartmental correlation to meniscal pathology and degree of chondrosis by MRI. Skeletal Radiol. 50 (11), 2185–2194 (2021). Allam, E. et al. Subchondral insufficiency fracture of the knee: unicompartmental correlation to meniscal pathology and degree of chondrosis by MRI. Skeletal Radiol. 50 (11), 2185–2194 (2021). Boehm, E. et al. Quantitative computed tomography has higher sensitivity detecting critical bone mineral density compared to dual-energy X-ray absorptiometry in postmenopausal women and elderly men with osteoporotic fractures: a real-life study. Arch. Orthop. Trauma. SurgDOI . 10.1007/s00402-023-05070-y (2023). Brown, M. L., McCauley, J. C., Gracitelli, G. C. & Bugbee, W. D. Osteochondritis Dissecans Lesion Location Is Highly Concordant With Mechanical Axis Deviation. Am. J. Sports Med. 48 (4), 871–875 (2020). Cleland, L. G., Bowey, R. R., Henderson, D. R. & Milazzo, S. C. Spontaneous osteonecrosis of the medial femoral condyle. Med. J. Aust . 2 (3), 92–94 (1976). Gorbachova, T., Melenevsky, Y., Cohen, M. & Cerniglia, B. W. Osteochondral Lesions of the Knee: Differentiating the Most Common Entities at MRI. Radiographics 38 (5), 1478–1495 (2018). Hussain, Z. B., Chahla, J., Mandelbaum, B. R., Gomoll, A. H. & LaPrade, R. F. The Role of Meniscal Tears in Spontaneous Osteonecrosis of the Knee: A Systematic Review of Suspected Etiology and a Call to Revisit Nomenclature. Am. J. Sports Med. 47 (2), 501–507 (2019). JE, K. E., CE, A. G. A. P. A., ML B, B., DB, D. F. M. I. S. P. & H, EM L Clinical use of quantitative computed tomography and peripheral quantitative computed tomography in the management of osteoporosis in adults: the 2007 ISCD Official Positions. J. Clin. DensitomDOI . 10.1016/J.JOCD.2007.12.010 (2008). Lee, S. & Saifuddin, A. Magnetic resonance imaging of subchondral insufficiency fractures of the lower limb. Skeletal Radiol. 48 (7), 1011–1021 (2019). Lee, S. & Saifuddin, A. Magnetic resonance imaging of subchondral insufficiency fractures of the lower limb. Skeletal Radiol. 48 (7), 1011–1021 (2019). Lo, G. H. et al. The ratio of medial to lateral tibial plateau bone mineral density and compartment-specific tibiofemoral osteoarthritis. Osteoarthr. Cartil. 14 (10), 984–990 (2006). Lotke, P. A., Abend, J. A. & EML. The treatment of osteonecrosis of the medial femoral condyle (Clin Orthop Relat Res, 1982). Lotke, P. A., Nelson, C. L. & Lonner, J. H. Spontaneous osteonecrosis of the knee: tibial plateaus. Orthop. Clin. North. Am. 35 (3), 365–370 (2004). x. MA, M. Z. J. R. & D, J H Osteonecrosis diagnosed on MR images of the knee. Relationship to reduced bone mineral density determined by high resolution peripheral quantitative CT. Acta RadiolDOI . 10.1080/J.1600-0455.2003.00108.X (2003). Nelson, F. R. et al. Subchondral insufficiency fractures and spontaneous osteonecrosis of the knee may not be related to osteoporosis. Arch. Osteoporos. 9 , 194 (2014). Nelson, F. R. et al. Subchondral insufficiency fractures and spontaneous osteonecrosis of the knee may not be related to osteoporosis. Arch. Osteoporos. 9 , 194 (2014). Plett, S. K. et al. Femoral condyle insufficiency fractures: associated clinical and morphological findings and impact on outcome. Skeletal Radiol. 44 (12), 1785–1794 (2015). MP, R. H. J. D. L. W. W., ACA, J., HH, M. F. L. A. L. & IK, W. F. J. B. F. B. M. K. H, K E, FW R Quantitative CT of the knee in the IMI-APPROACH osteoarthritis cohort: Association of bone mineral density with radiographic disease severity, meniscal coverage and meniscal extrusion. Bone (2023). 10.1016/J.BONE.2023.116673 Reddy, A. S. & Frederick, R. W. Evaluation of the intraosseous and extraosseous blood supply to the distal femoral condyles. Am. J. Sports Med. 26 (3), 415–419 (1998). GC, S. A., WH, B. & B Spontaneous osteonecrosis of the knee. Arthritis RheumDOI . 10.1002/ART.1780110602 (1968). Q, T. X. Z. C. H. M. M. C. G. D., C, H., W T-M, B. Y. K. S. X. & L WW, Q Y One Novel Phantom-Less Quantitative Computed Tomography System for Auto-Diagnosis of Osteoporosis Utilizes Low-Dose Chest Computed Tomography Obtained for COVID-19 Screening. Front. Bioeng. BiotechnolDOI . 10.3389/FBIOE.2022.856753 (2022). n der Weiden, G. S. et al. Osteochondritis Dissecans of the Knee Associated With Mechanical Overload. Am. J. Sports Med. 52 (1), 155–163 (2024). Wilmot, A. S., Ruutiainen, A. T., Bakhru, P. T., Schweitzer, M. E. & Shabshin, N. Subchondral insufficiency fracture of the knee: A recognizable associated soft tissue edema pattern and a similar distribution among men and women. Eur. J. Radiol. 85 (11), 2096–2103 (2016). Zanetti, M., Romero, J., Dambacher, M. A. & Hodler, J. Osteonecrosis diagnosed on MR images of the knee. Relationship to reduced bone mineral density determined by high resolution peripheral quantitative CT. Acta Radiol. 44 (5), 525–531 (2003). Zhang, C. et al. Osteoporosis is associated with varus deformity in postmenopausal women with knee osteoarthritis: a cross-sectional study. BMC Musculoskelet. Disord . 22 (1), 694 (2021). C, Z. J. L. et al. Automatic phantom-less QCT system with high precision of BMD measurement for osteoporosis screening: Technique optimisation and clinical validation. J. Orthop. TranslatDOI . 10.1016/J.JOT.2021.11.008 (2022). ACR-SPR-SSR PRACTICE PARAMETER FOR THE PERFORMANCE OF QUANTITATIVE COMPUTED TOMOGRAPHY (QCT) BONE MINERAL DENSITY. Tables Table 1 Detail CT scanning parameters using in our research Manufacturer GE-revolution CT Philips IQon CT Toshiba Aquilion CT Voltage(kV) 120 120 120 mA 254 200 220 SFOV (mm) 500 500 500 Matrix 512*512 512*512 512*512 Slice thickness (mm) 1 1 2 Reconstruction kernel Standard Standard Standard Table 2 Comparison of patients’ characteristics between the SIFK and KOA groups Variable SIFK group KOA group P value Age, years 65 (62-68) 67 (64-70) 0.324 a Height, centimeter 157 (155-159) 158 (155-160) 0.759 a Weight, kilogram 62 (59-64) 65 (61-69) 0.125 a Body mass index, kg/cm 2 26 (24-28) 25 (23-26) 0.209 a Hyperlipidemia Knee Society Score, points Pain 33 (31-35) 36 (33-38) 0.125 b Function 41 (37-44) 54 (51-57) <0.001 b a Student’s t-test b Mann-Whitney test SIFK, subchondral insufficiency fracture of knee; KOA, knee osteoarthritis. Table 3 Radiology characteristics between the SIFK and KOA groups Variable SIFK group KOA group Kellgren-Lawrence grade Grade 1 2 0 Grade 2 5 5 Grade 3-4 25 23 Kushino Stage Stage 1 2 - Stage 2 8 - Stage 3-4 22 - Sides Left 23 9 Right 9 19 SIFK, subchondral insufficiency fracture of knee; KOA, knee osteoarthritis. Table 4 Comparison of BMD at various locations and medial-lateral ratios between the SIFK and KOA groups Variable SIFK group KOA group P-value Femoral neck BMD, g/cm 3 0.87 (0.79-0.94) 0.82 (0.77-0.86) 0.241 a Low BMD/normal BMD based on the T-score at the femoral neck c 18/10 15/13 - Subchondral BMD of medial femoral condyle, mg/cm 3 263.87(238.37-289.36) 256.99(213.22-300.76) 0.782 a Mid-epiphyseal BMD of medial femoral condyle, mg/cm 3 184.34(161.38-207.29) 166.30(134.56-198.04) 0.350 a Femoral medial/lateral ratio Subchondral 1.69(1.47-1.91) 1.86(1.46-2.26) 0.449 a Mid-epphyseal 1.64(1.43-1.86) 1.59(1.22-1.97) 0.81 a Subchondral BMD of medial tibial condyle, mg/cm 3 194.38(162.26-226.49) 245.33(201.85-288.82) 0.055 b Mid-epiphyseal BMD of medial femoral condyle, mg/cm 3 140.35(115.69-165.00) 173.20(138.44-207.95) 0.114 b Tibial medial/lateral ratio Subchondral 1.47(1.22-1.72) 2.35(1.65-3.05) 0.014 a Mid-epphyseal 1.77(1.45-2.09) 3.91(2.15-5.67) 0.02 a Femoral osteonecrosis BMD, mg/cm 63.9 (55.3-72.5) a Student’s t-test b Mann-Whitney test c Low BMD was defined as a T score of –1 or less. The values showed in the table are given as mean number (95% CI). SIFK, subchondral insufficiency fracture of knee; KOA, knee osteoarthritis; BMD, bone mineral density. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted 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. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-6245969","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":435183798,"identity":"a004bd3b-5732-40fc-8b65-6b8b0e18755c","order_by":0,"name":"Zijie Zhang","email":"","orcid":"","institution":"The first affiliated hospital of Fujian Medical University","correspondingAuthor":false,"prefix":"","firstName":"Zijie","middleName":"","lastName":"Zhang","suffix":""},{"id":435183799,"identity":"358e9a7b-21b3-46d4-b42b-077b8138265c","order_by":1,"name":"Changyu Huang","email":"","orcid":"","institution":"Quanzhou Orthopedic-traumatological Hospital","correspondingAuthor":false,"prefix":"","firstName":"Changyu","middleName":"","lastName":"Huang","suffix":""},{"id":435183801,"identity":"5453c223-68c4-483a-bd8e-e4e3bcd133b2","order_by":2,"name":"Xinyu Fang","email":"","orcid":"","institution":"The first affiliated hospital of Fujian Medical University","correspondingAuthor":false,"prefix":"","firstName":"Xinyu","middleName":"","lastName":"Fang","suffix":""},{"id":435183804,"identity":"fa00d4f5-0664-463b-a15f-e8a9eb2d1a19","order_by":3,"name":"Yang Chen","email":"","orcid":"","institution":"The first affiliated hospital of Fujian Medical University","correspondingAuthor":false,"prefix":"","firstName":"Yang","middleName":"","lastName":"Chen","suffix":""},{"id":435183805,"identity":"3546eb8f-ce31-4731-9d21-b5d9dbe71f21","order_by":4,"name":"Wenming Zhang","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABBElEQVRIiWNgGAWjYDACCQjFY9/e2PigggfMMSBKi5wBz+FmgzOkaDE2kEhvkzjDQIQW+dnNzx5+bduWuF0isa3igMy2xAb25m0SDDV3cGphnHPM3Fi27Xbizp6HbTcO8NxObOA5VibBcOwZTi3MEglm0pLbgCqPJ7bd/gDSIpFjJsHYcBinFjaJ9G8QLQcS2wrAtsi/wa+FB2im5Mdtt40NTiS2MYC1SPDg1yIhkVMmzfjvtpxkz8FmCaAW4zaetGKLhGO4tcjPSN8m+ePMbR5+9vaHHw723JbtZz+88caHGtxawEHAA2Mx9gB9B2Ik4NUAVPgDzvyBR9koGAWjYBSMWAAAlspeRzfajB8AAAAASUVORK5CYII=","orcid":"","institution":"The first affiliated hospital of Fujian Medical University","correspondingAuthor":true,"prefix":"","firstName":"Wenming","middleName":"","lastName":"Zhang","suffix":""},{"id":435183807,"identity":"682e0480-3d1e-4e55-842d-96c48112c765","order_by":5,"name":"Zida Huang","email":"","orcid":"","institution":"The first affiliated hospital of Fujian Medical University","correspondingAuthor":false,"prefix":"","firstName":"Zida","middleName":"","lastName":"Huang","suffix":""}],"badges":[],"createdAt":"2025-03-17 15:23:21","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6245969/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6245969/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":81344291,"identity":"20dbcb1b-e1d6-4010-8989-b5fb6d0060fa","added_by":"auto","created_at":"2025-04-25 04:16:48","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":774972,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6245969/v1/cf55161d-c423-4f1e-b1c4-9e754bd675f6.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Low bone mineral density is not a predictive factor for subchondral insufficiency fracture of the knee, based on the analysis of QCT studies","fulltext":[{"header":"Introduction","content":"\u003cp\u003eSubchondral insufficiency fracture of the knee (SIFK) is characterized as damage resulting from repetitive mechanical stress on the joints [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. In the past researches, stress fracture usually occurs in our weight-bearing joints or bones which is referred to insufficiency fractures[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eAs we all know, Ahlb\u0026auml;ck et al. first described the disease \u0026ldquo;spontaneous osteonecrosis of the knee\u0026rdquo; (SONK) in 1968[\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. With the deepening of researches, it is gradually accepted that SONK is the terminal stage manifestation of SIFK[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Therefore, nowadays SIFK and SONK are both applied to describe the stress fracture of the knee joints.\u003c/p\u003e \u003cp\u003eBased on the definition of insufficiency fracture, reduced bone mineral density(BMD) was used to be a potential risk for SIFK. Zanetti et al. found that there were about two thirds of the patients who suffered from the osteoporosis or osteopenia in a cohort of 32 samples[\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. Another research reported that low BMD occurred in lateral femoral, tibial condyle and femoral neck in SONK groups compared with knee osteoarthritis (KOA) groups in a cohort of 52 female patients[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. However, it was reported that only 16% (5/32) of SIFK patients were diagnosed as osteoporosis, proving that reduced BMD might not consider as a potential risk for SIFK[\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eTo the best of our knowledge, the relationship between SIFK and low BMD remains controversial, and no study has yet established a definitive association between BMD at a specific threshold and the occurrence of SIFK. In addition, most of the research were used dual-energy X-ray absorptiometry. We would like to applied a novel automatic phantom-less QCT BMD Analysis in our research to detected the association between the low BMD and SIFK.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e\u003cstrong\u003eDemographic characteristics\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTwo authors (ZJ and ZD) assessed the area of 40 femoral osteonecrosis in the pre-experimental group, achieving an inter-observer intraclass correlation coefficient of 0.912. Additionally, these authors classified the SIFK lesions, obtaining a kappa coefficient of 0.87.\u003c/p\u003e\n\u003cp\u003eWe identified 32 patients in the SIFK group and 28 patients in the OA group, with all participants being counted for unilateral knees only. The patients’ characteristics were listed in the Table 2, in which no significant difference was found according to the age, BMI. In the SIFK group, the Kellgren and Lawrence grades included grade two in five knees, grade three in five knees, and grades three-four in 25 knees. In the KOA group, there were five knees with grade two and 23 knees with grades three-four. The Kushino radiographic stages of SIFK at the time of diagnosis were stage one in two knees, stage two in eight knees, and stages three-four in 22 knees (Table 3).\u003cbr\u003e\u003cstrong\u003eDifferences in BMD between the two groups\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe mean femoral neck BMD showed no significant difference between the SIFK and KOA groups according to traditional DXA methods (p = 0.241). However, we observed that some patients in both groups exhibited low BMDs at the femoral neck. In contrast, there was no statistically significant difference in the Sub-BMD of the medial femoral condyle between the two groups, with values of 263.87 g/cm³ and 256.99 g/cm³, respectively. A similar outcome was noted for the Mid-BMD of the medial femoral condyle, which measured 184.34 g/cm³ in the SIFK group and 166.30 g/cm³ in the KOA group. The mean medial and lateral BMDs of the tibial condyle were not statistically significant between the SIFK and KOA groups (p = 0.055 and p = 0.114, respectively). Nevertheless, the mean tibial M-L ratios were significantly higher in the KOA group compared to the SIFK group. Additionally, there was no difference in the mean femoral ratios where all the bone necrosis occurred between the SIFK and KOA groups (Table 4). The mean BMD of the osteonecrosis area in the SIFK group was 63.9 g/cm³, which would be classified as osteoporosis according to ACR guidelines.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eWe observed that the BMD of the femoral neck, subchondral and mid-epiphyseal regions of the medial femoral condyle, as well as the medial tibial condyle, exhibited no statistically significant differences between the SIFK and KOA patients. The only notable finding was that the tibial M-L ratio was significantly higher in the KOA patients compared to those with SIFK, whereas no differences were observed in the femoral M-L ratios at the sites of osteonecrosis. Our results do not support the theory that subchondral insufficiency fractures due to low BMD are a contributing factor in the onset of SIFK.\u003c/p\u003e\n\u003cp\u003eSIFK is a type of insufficiency fracture, characterized as a form of stress fracture that tends to occur in the weight-bearing joints of the lower legs[13].\u0026nbsp;According to this definition, low bone mineral density (BMD) has traditionally been regarded as a risk factor for SIFK. Several studies have reported a link between low BMD and SIFK[2, 17, 20].For instance, Akamatsu et al. compared the BMD of 26 women with SONK to that of 26 women with medial knee osteoarthritis (OA) using DXA methods. They concluded that some elderly women may experience microfractures in the femoral condyles due to the rapid progression of low BMD[2].\u0026nbsp;However, in a more recent study, Nelson et al. found that only 16% (5 out of 32) of SIFK patients were classified as having osteoporosis, suggesting that low BMD may not be the primary risk factor for SIFK[19].\u0026nbsp;As far as we know, the relationship between low BMD and SIFK remains a topic of controversy.\u003c/p\u003e\n\u003cp\u003eIn our study, approximately half of the 60 patients had low bone density in the femoral neck measured by conventional DXA technology, and the majority of SIFK patients were elderly females which is similar to previous results[2]. By using the Automatic Phantom-Less QCT, we also found located low BMD in the medial femoral condyle and medial tibial in both the SIFK and OA groups. However, the proportion of low BMD patients was limited which was 3/32 (the SIFK group) and 4/28 (the OA group), respectively. This reflects that low BMD might not be a predictive factor for the occurrence of SIFK or OA. Additionally, several studies have identified an association between knee OA and SIFK[8, 20]. Allam et al. reported that the extent of chondrosis was correlated with the severity of SIFK[5]. Similarly, Plett et al. found that 75.7% (53 out of 70) of SIFK patients exhibited overlying full-thickness cartilage loss, and 94.1% (64 out of 68) had ipsilateral meniscal injuries[20]. These findings suggest that meniscal injuries may be linked to the development of both SIFK and OA.\u003c/p\u003e\n\u003cp\u003eAn abnormal M-L ratio in patients with KOA or SIFK is linked to an increase in varus deformity, bone marrow lesions, osteophyte formation, joint space narrowing, and subchondral sclerosis.[2, 14, 28]. However, the statistically consistent femoral M-L ratio in two groups in our study was not matched to the previous findings[2]. Most of the previous studies were not calculated the femoral condyle BMD, but using femoral neck or lumbar spine ones. Recent studies have shown that quantitative computed tomography (QCT) is a more sensitive method for diagnosing osteoporosis and predicting fractures than dual-energy X-ray absorptiometry (DXA).[6]. Above all, we speculate these results might prove the potential association between OA and SIFK, that is the SIFK patients had suffered from OA before the onset of osteonecrosis.\u003c/p\u003e\n\u003cp\u003eSIFK is reported to be more command in female patients over 50 years old, and most were found at the weight-bearing area[20, 26]. Due to age-related changes in estrogen levels, low bone mineral density (BMD) has been regarded as a contributing factor in the higher prevalence of SIFK among older women. The traditional DXA method evaluates the systematic BMD of patients, while the measurements of local ones are relatively weak. The principle of QCT is to measure BMD within the selected volume, which has certain advantages[6]. SIFK has been reported to be associated with blood supply to the femoral condyles, mechanical overload, or mechanical axis deviation[7, 22, 25]. The area of osteonecrosis resulting from subchondral fractures has been pathologically shown to comprise a mixture of a series of pathophysiological processes, occurring in varying proportions[3]. According to consensus definition, osteoporosis only represents changes in bone density during fracture healing and does not reflect the presence of local bone mass before the fracture. Additionally, a previous report found that the area affected by SIFK may extend over a substantial portion of the involved condyle[9].\u003c/p\u003e\n\u003cp\u003eThere were several limitations in our study. First, as the inherent flaws in retrospective research, the measurement of bone density and CT scan in our center was not tested as a routine item for a long time, resulting in the loss of a large number of reliable cases. In addition, due to the large time span of inclusion, there are 3 types of devices used for CT image acquisition (Table 1). Previous literature has reported that there may be bias because of the images obtained with different CT scanning parameters[24].\u003c/p\u003e\n\u003cp\u003eWe believe that SIFK were discovered due to the bone marrow edema reaction after local trabecular fracture caused by excessive stress load and pre-existing OA, not by the low BMD as a predictive factor. Future investigations should consider on the association between the early stage of subchondral fracture and local BMD.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003ePatient population\u003c/h2\u003e \u003cp\u003ePatients diagnosed with SONK or SIFK admitted to the two centers from 2017 to 2023 were retrospectively analyzed (the SIFK group), which was based on the criteria of SONK and SIFK defined by Ahlb\u0026auml;ck et al. and Lotke et al[\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. All patients had no medical record of corticosteroid intake, alcohol abuse, knee trauma or intra-articular injection during the period of joint pain. Due to the conditions required by QCT testing, cases in which one mm or two mm thin slice images were not taken were excluded from our study.\u003c/p\u003e \u003cp\u003eWe enrolled 26 patients with knee osteoarthritis (the KOA group) as the control group and recorded their femoral neck bone mineral density (BMD) using a Lunar Prodigy scanner (GE, Madison, WI, USA). Initially, we obtained relevant data, including Knee Society Scores, knee function scores, and pain scores.\u003c/p\u003e \u003cp\u003e Our study received approval from the institutional review board (protocol number: MRCTA, ECFAH of FMU [2020]289). Informed consent was obtained from all patients participating in the study. We confirmed that all research was performed in accordance with the Declaration of Helsinki.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eRadiography\u003c/h2\u003e \u003cp\u003eAll patients in two goups need to collect their standing anteroposterior and lateral knee radiological films. The radiograph was also applied to distinguish the grade of disease in the SIFK group, which was classified into four stages[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eMagnetic Resonance Imaging\u003c/h3\u003e\n\u003cp\u003eMagnetic resonance imaging (MRI) was the regular examination in SIFK group. The diagnostic criteria for SIFK or SONK on MRI included a distinct decrease in intensity on the T1-weighted image, along with a corresponding decrease in intensity surrounded by a high-intensity area\u0026ndash;indicating bone marrow swelling\u0026ndash;on the T2-weighted and fat-suppressed images of the inner femoral condyle.\u003c/p\u003e\n\u003ch3\u003eComputed Tomography\u003c/h3\u003e\n\u003cp\u003eComputed Tomography (CT) images were captured by three different devices in the center, GE-revolution CT and Philips IQon CT. The parameters of the CT machine are described in the Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e1\u003c/span\u003e. All patients took bilateral knee CT 3D reconstruction examinations, and uploaded thin-slice images with a thickness of one mm for follow-up testing.\u003c/p\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eAutomatic Phantom-Less QCT BMD Analysis\u003c/h2\u003e \u003cp\u003e We employed an automatic phantom-less QCT software, FRAX BMD 1.0 (Bo-Zhi Biotech, Shenzhen, China), suited for localized BMD assessments, encompassing both cancellous and cortical bone. This innovative PL-QCT features an automatic capability to identify vertebrae, hip, fat, and muscle regions of interest (ROI) while ensuring precise calibration of BMD. A comprehensive overview of the development process of this phantom-less QCT technology can be found in prior research[\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e, \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. The CT values from the fat and muscle regions of interest (ROI) have been utilized to adjust the BMD results.\u003c/p\u003e \u003cp\u003eAs the definition of anatomic coordinate systems in previous study[\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e], we detected the number of BMD in weight-bearing area of the regions of interest (ROI), including subchondral (Sub) and mid-epiphyseal (Mid). Both sides of femur and tibia were measured. Regarding of osteochondral defects, we measured BMD of ROI described in the methodology, as well as the approximate density within the defect range based on CT and MRI images.\u003c/p\u003e \u003cp\u003eThe ratios of medial condyle BMD to lateral one (M-L ratios) in both the femur and tibia were computed as comparative parameters for the two compartments. Patients were classified based on the WHO criteria (1994). A T-score greater than \u0026minus;\u0026thinsp;1 was classified as normal, a T-score between \u0026minus;\u0026thinsp;1 and \u0026minus;\u0026thinsp;2.49 was designated as osteopenia, and a T-score of \u0026minus;\u0026thinsp;2.5 or lower was categorized as osteoporosis. Additionally, osteopenia and osteoporosis were grouped together under the term low BMD.\u003c/p\u003e \u003cp\u003eAccording to the guidelines of the American College of Radiology (ACR) in 2008 on practical parameters for BMD in musculoskeletal QCT and their 2013 revision, BMD value\u0026thinsp;\u0026gt;\u0026thinsp;120 mg/cm\u003csup\u003e3\u003c/sup\u003e indicates normal ones, 80\u0026thinsp;~\u0026thinsp;120 mg/cm\u003csup\u003e3\u003c/sup\u003e indicates osteopenia, and \u0026lt;\u0026thinsp;80mg/cm\u003csup\u003e3\u003c/sup\u003e indicates osteoporosis[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eStatistics\u003c/h2\u003e \u003cp\u003eData were presented as the mean accompanied by a 95% confidence interval (CI). The Shapiro-Wilk test was employed to assess the normality of the data. Differences between the groups were evaluated using Student\u0026rsquo;s t-test for continuous variables that followed a normal distribution, whereas the Mann-Whitney test was applied when the data did not meet this criterion. Statistical analyses were conducted using SPSS software version 17. A p-value of less than 0.05 was deemed significant.\u003c/p\u003e \u003c/div\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors thank all participants that agreed to participate in this study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor Contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by Zijie Zhang, Zida Huang and Changyu Huang. The first draft of the manuscript was written by Zijie Zhang and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData Availability\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe data that support the findings of this study are available from corresponding author, but restrictions apply to the availability of these data, which were used under licence for the current study and so are not publicly available. The data are, however, available from the authors upon reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interest\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors have no relevant financial or non-financial interests to disclose.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthic Approval\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eOur study received approval from the institutional review board (protocol number: MRCTA, ECFAH of FMU [2020]289). Informed consent was obtained from all patients participating in the study.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eAkamatsu, Y., Mitsugi, N., Hayashi, T., Kobayashi, H. \u0026amp; Saito, T. Low bone mineral density is associated with the onset of spontaneous osteonecrosis of the knee. \u003cem\u003eActa Orthop.\u003c/em\u003e \u003cb\u003e83\u003c/b\u003e (3), 249\u0026ndash;255 (2012).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAkamatsu, Y., Mitsugi, N., Hayashi, T., Kobayashi, H. \u0026amp; Saito, T. Low bone mineral density is associated with the onset of spontaneous osteonecrosis of the knee. \u003cem\u003eActa Orthop.\u003c/em\u003e \u003cb\u003e83\u003c/b\u003e (3), 249\u0026ndash;255 (2012).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAkhavan, S., Martinkovich, S. C., Kasik, C. \u0026amp; DeMeo, P. J. Bone Marrow Edema, Clinical Significance, and Treatment Options: A Review. \u003cem\u003eJ. Am. Acad. Orthop. Surg.\u003c/em\u003e \u003cb\u003e28\u003c/b\u003e (20), e888\u0026ndash;e899 (2020).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAllam, E. et al. Subchondral insufficiency fracture of the knee: unicompartmental correlation to meniscal pathology and degree of chondrosis by MRI. \u003cem\u003eSkeletal Radiol.\u003c/em\u003e \u003cb\u003e50\u003c/b\u003e (11), 2185\u0026ndash;2194 (2021).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAllam, E. et al. Subchondral insufficiency fracture of the knee: unicompartmental correlation to meniscal pathology and degree of chondrosis by MRI. \u003cem\u003eSkeletal Radiol.\u003c/em\u003e \u003cb\u003e50\u003c/b\u003e (11), 2185\u0026ndash;2194 (2021).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBoehm, E. et al. Quantitative computed tomography has higher sensitivity detecting critical bone mineral density compared to dual-energy X-ray absorptiometry in postmenopausal women and elderly men with osteoporotic fractures: a real-life study. \u003cem\u003eArch. Orthop. Trauma. SurgDOI\u003c/em\u003e. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1007/s00402-023-05070-y\u003c/span\u003e\u003cspan address=\"10.1007/s00402-023-05070-y\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e (2023).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBrown, M. L., McCauley, J. C., Gracitelli, G. C. \u0026amp; Bugbee, W. D. Osteochondritis Dissecans Lesion Location Is Highly Concordant With Mechanical Axis Deviation. \u003cem\u003eAm. J. Sports Med.\u003c/em\u003e \u003cb\u003e48\u003c/b\u003e (4), 871\u0026ndash;875 (2020).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCleland, L. G., Bowey, R. R., Henderson, D. R. \u0026amp; Milazzo, S. C. Spontaneous osteonecrosis of the medial femoral condyle. \u003cem\u003eMed. J. Aust\u003c/em\u003e. \u003cb\u003e2\u003c/b\u003e (3), 92\u0026ndash;94 (1976).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGorbachova, T., Melenevsky, Y., Cohen, M. \u0026amp; Cerniglia, B. W. Osteochondral Lesions of the Knee: Differentiating the Most Common Entities at MRI. \u003cem\u003eRadiographics\u003c/em\u003e \u003cb\u003e38\u003c/b\u003e (5), 1478\u0026ndash;1495 (2018).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHussain, Z. B., Chahla, J., Mandelbaum, B. R., Gomoll, A. H. \u0026amp; LaPrade, R. F. The Role of Meniscal Tears in Spontaneous Osteonecrosis of the Knee: A Systematic Review of Suspected Etiology and a Call to Revisit Nomenclature. \u003cem\u003eAm. J. Sports Med.\u003c/em\u003e \u003cb\u003e47\u003c/b\u003e (2), 501\u0026ndash;507 (2019).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJE, K. E., CE, A. G. A. P. A., ML B, B., DB, D. F. M. I. S. P. \u0026amp; H, EM L Clinical use of quantitative computed tomography and peripheral quantitative computed tomography in the management of osteoporosis in adults: the 2007 ISCD Official Positions. \u003cem\u003eJ. Clin. DensitomDOI\u003c/em\u003e. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/J.JOCD.2007.12.010\u003c/span\u003e\u003cspan address=\"10.1016/J.JOCD.2007.12.010\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e (2008).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLee, S. \u0026amp; Saifuddin, A. Magnetic resonance imaging of subchondral insufficiency fractures of the lower limb. \u003cem\u003eSkeletal Radiol.\u003c/em\u003e \u003cb\u003e48\u003c/b\u003e (7), 1011\u0026ndash;1021 (2019).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLee, S. \u0026amp; Saifuddin, A. Magnetic resonance imaging of subchondral insufficiency fractures of the lower limb. \u003cem\u003eSkeletal Radiol.\u003c/em\u003e \u003cb\u003e48\u003c/b\u003e (7), 1011\u0026ndash;1021 (2019).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLo, G. H. et al. The ratio of medial to lateral tibial plateau bone mineral density and compartment-specific tibiofemoral osteoarthritis. \u003cem\u003eOsteoarthr. Cartil.\u003c/em\u003e \u003cb\u003e14\u003c/b\u003e (10), 984\u0026ndash;990 (2006).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLotke, P. A., Abend, J. A. \u0026amp; EML. \u003cem\u003eThe treatment of osteonecrosis of the medial femoral condyle\u003c/em\u003e (Clin Orthop Relat Res, 1982).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLotke, P. A., Nelson, C. L. \u0026amp; Lonner, J. H. Spontaneous osteonecrosis of the knee: tibial plateaus. \u003cem\u003eOrthop. Clin. North. Am.\u003c/em\u003e \u003cb\u003e35\u003c/b\u003e (3), 365\u0026ndash;370 (2004). x.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMA, M. Z. J. R. \u0026amp; D, J H Osteonecrosis diagnosed on MR images of the knee. Relationship to reduced bone mineral density determined by high resolution peripheral quantitative CT. \u003cem\u003eActa RadiolDOI\u003c/em\u003e. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1080/J.1600-0455.2003.00108.X\u003c/span\u003e\u003cspan address=\"10.1080/J.1600-0455.2003.00108.X\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e (2003).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNelson, F. R. et al. Subchondral insufficiency fractures and spontaneous osteonecrosis of the knee may not be related to osteoporosis. \u003cem\u003eArch. Osteoporos.\u003c/em\u003e \u003cb\u003e9\u003c/b\u003e, 194 (2014).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNelson, F. R. et al. Subchondral insufficiency fractures and spontaneous osteonecrosis of the knee may not be related to osteoporosis. \u003cem\u003eArch. Osteoporos.\u003c/em\u003e \u003cb\u003e9\u003c/b\u003e, 194 (2014).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePlett, S. K. et al. Femoral condyle insufficiency fractures: associated clinical and morphological findings and impact on outcome. \u003cem\u003eSkeletal Radiol.\u003c/em\u003e \u003cb\u003e44\u003c/b\u003e (12), 1785\u0026ndash;1794 (2015).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMP, R. H. J. D. L. W. W., ACA, J., HH, M. F. L. A. L. \u0026amp; IK, W. F. J. B. F. B. M. K. H, K E, FW R Quantitative CT of the knee in the IMI-APPROACH osteoarthritis cohort: Association of bone mineral density with radiographic disease severity, meniscal coverage and meniscal extrusion. Bone (2023). \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/J.BONE.2023.116673\u003c/span\u003e\u003cspan address=\"10.1016/J.BONE.2023.116673\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eReddy, A. S. \u0026amp; Frederick, R. W. Evaluation of the intraosseous and extraosseous blood supply to the distal femoral condyles. \u003cem\u003eAm. J. Sports Med.\u003c/em\u003e \u003cb\u003e26\u003c/b\u003e (3), 415\u0026ndash;419 (1998).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGC, S. A., WH, B. \u0026amp; B Spontaneous osteonecrosis of the knee. \u003cem\u003eArthritis RheumDOI\u003c/em\u003e. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1002/ART.1780110602\u003c/span\u003e\u003cspan address=\"10.1002/ART.1780110602\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e (1968).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eQ, T. X. Z. C. H. M. M. C. G. D., C, H., W T-M, B. Y. K. S. X. \u0026amp; L WW, Q Y One Novel Phantom-Less Quantitative Computed Tomography System for Auto-Diagnosis of Osteoporosis Utilizes Low-Dose Chest Computed Tomography Obtained for COVID-19 Screening. \u003cem\u003eFront. Bioeng. BiotechnolDOI\u003c/em\u003e. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.3389/FBIOE.2022.856753\u003c/span\u003e\u003cspan address=\"10.3389/FBIOE.2022.856753\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e (2022).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003en der Weiden, G. S. et al. Osteochondritis Dissecans of the Knee Associated With Mechanical Overload. \u003cem\u003eAm. J. Sports Med.\u003c/em\u003e \u003cb\u003e52\u003c/b\u003e (1), 155\u0026ndash;163 (2024).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWilmot, A. S., Ruutiainen, A. T., Bakhru, P. T., Schweitzer, M. E. \u0026amp; Shabshin, N. Subchondral insufficiency fracture of the knee: A recognizable associated soft tissue edema pattern and a similar distribution among men and women. \u003cem\u003eEur. J. Radiol.\u003c/em\u003e \u003cb\u003e85\u003c/b\u003e (11), 2096\u0026ndash;2103 (2016).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eZanetti, M., Romero, J., Dambacher, M. A. \u0026amp; Hodler, J. Osteonecrosis diagnosed on MR images of the knee. Relationship to reduced bone mineral density determined by high resolution peripheral quantitative CT. \u003cem\u003eActa Radiol.\u003c/em\u003e \u003cb\u003e44\u003c/b\u003e (5), 525\u0026ndash;531 (2003).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eZhang, C. et al. Osteoporosis is associated with varus deformity in postmenopausal women with knee osteoarthritis: a cross-sectional study. \u003cem\u003eBMC Musculoskelet. Disord\u003c/em\u003e. \u003cb\u003e22\u003c/b\u003e (1), 694 (2021).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eC, Z. J. L. et al. Automatic phantom-less QCT system with high precision of BMD measurement for osteoporosis screening: Technique optimisation and clinical validation. \u003cem\u003eJ. Orthop. TranslatDOI\u003c/em\u003e. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/J.JOT.2021.11.008\u003c/span\u003e\u003cspan address=\"10.1016/J.JOT.2021.11.008\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e (2022).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eACR-SPR-SSR PRACTICE PARAMETER FOR THE PERFORMANCE OF QUANTITATIVE COMPUTED TOMOGRAPHY (QCT) BONE MINERAL DENSITY.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003e\u003cstrong\u003eTable 1 Detail CT scanning parameters using in our research\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24.6046%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eManufacturer\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.9561%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eGE-revolution CT\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.9561%;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePhilips IQon CT\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25.4833%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eToshiba Aquilion CT\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24.6046%;\"\u003e\n \u003cp\u003eVoltage(kV)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.9561%;\"\u003e\n \u003cp\u003e120\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.9561%;\"\u003e\n \u003cp\u003e120\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25.4833%;\"\u003e\n \u003cp\u003e120\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24.6046%;\"\u003e\n \u003cp\u003emA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.9561%;\"\u003e\n \u003cp\u003e254\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.9561%;\"\u003e\n \u003cp\u003e200\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25.4833%;\"\u003e\n \u003cp\u003e220\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24.6046%;\"\u003e\n \u003cp\u003eSFOV (mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.9561%;\"\u003e\n \u003cp\u003e500\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.9561%;\"\u003e\n \u003cp\u003e500\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25.4833%;\"\u003e\n \u003cp\u003e500\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24.6046%;\"\u003e\n \u003cp\u003eMatrix\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.9561%;\"\u003e\n \u003cp\u003e512*512\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.9561%;\"\u003e\n \u003cp\u003e512*512\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25.4833%;\"\u003e\n \u003cp\u003e512*512\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24.6046%;\"\u003e\n \u003cp\u003eSlice thickness (mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.9561%;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.9561%;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25.4833%;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 24.6046%;\"\u003e\n \u003cp\u003eReconstruction kernel\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.9561%;\"\u003e\n \u003cp\u003eStandard\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.9561%;\"\u003e\n \u003cp\u003eStandard\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25.4833%;\"\u003e\n \u003cp\u003eStandard\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003eTable 2 Comparison of patients\u0026rsquo; characteristics between the SIFK and KOA groups\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 27.993%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariable\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.6479%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSIFK group\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.6479%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eKOA group\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 22.7113%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 27.993%;\"\u003e\n \u003cp\u003eAge, years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.6479%;\"\u003e\n \u003cp\u003e65 (62-68)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.6479%;\"\u003e\n \u003cp\u003e67 (64-70)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 22.7113%;\"\u003e\n \u003cp\u003e0.324\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 27.993%;\"\u003e\n \u003cp\u003eHeight, centimeter\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.6479%;\"\u003e\n \u003cp\u003e157 (155-159)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.6479%;\"\u003e\n \u003cp\u003e158 (155-160)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 22.7113%;\"\u003e\n \u003cp\u003e0.759\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 27.993%;\"\u003e\n \u003cp\u003eWeight, kilogram\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.6479%;\"\u003e\n \u003cp\u003e62 (59-64)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.6479%;\"\u003e\n \u003cp\u003e65 (61-69)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 22.7113%;\"\u003e\n \u003cp\u003e0.125\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 27.993%;\"\u003e\n \u003cp\u003eBody mass index, kg/cm\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.6479%;\"\u003e\n \u003cp\u003e26 (24-28)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.6479%;\"\u003e\n \u003cp\u003e25 (23-26)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 22.7113%;\"\u003e\n \u003cp\u003e0.209\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 27.993%;\"\u003e\n \u003cp\u003eHyperlipidemia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.6479%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.6479%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 22.7113%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 27.993%;\"\u003e\n \u003cp\u003eKnee Society Score, points\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.6479%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.6479%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 22.7113%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 27.993%;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Pain\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.6479%;\"\u003e\n \u003cp\u003e33 (31-35)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.6479%;\"\u003e\n \u003cp\u003e36 (33-38)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 22.7113%;\"\u003e\n \u003cp\u003e0.125\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 27.993%;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Function\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.6479%;\"\u003e\n \u003cp\u003e41 (37-44)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 24.6479%;\"\u003e\n \u003cp\u003e54 (51-57)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 22.7113%;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003csup\u003ea\u003c/sup\u003eStudent\u0026rsquo;s t-test\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003csup\u003eb\u003c/sup\u003eMann-Whitney test\u003c/p\u003e\n\u003cp\u003eSIFK, subchondral insufficiency fracture of knee; KOA, knee osteoarthritis.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 3 Radiology characteristics between the SIFK and KOA groups\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariable\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSIFK group\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eKOA group\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003eKellgren-Lawrence grade\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e\u0026nbsp; Grade 1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e\u0026nbsp; Grade 2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e\u0026nbsp; Grade 3-4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e23\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003eKushino Stage\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e\u0026nbsp; Stage 1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e\u0026nbsp; Stage 2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e\u0026nbsp; Stage 3-4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003eSides\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e\u0026nbsp; Left\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e\u0026nbsp; Right\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 33.3333%;\"\u003e\n \u003cp\u003e19\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eSIFK, subchondral insufficiency fracture of knee; KOA, knee osteoarthritis.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 4 Comparison of BMD at various locations and medial-lateral ratios between the SIFK and KOA groups\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 36.2676%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariable\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.5845%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSIFK group\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.5845%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eKOA group\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10.5634%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP-value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 36.2676%;\"\u003e\n \u003cp\u003eFemoral neck BMD, g/cm\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.5845%;\"\u003e\n \u003cp\u003e0.87 (0.79-0.94)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.5845%;\"\u003e\n \u003cp\u003e0.82 (0.77-0.86)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10.5634%;\"\u003e\n \u003cp\u003e0.241\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 36.2676%;\"\u003e\n \u003cp\u003eLow BMD/normal BMD based on the T-score at the femoral neck\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.5845%;\"\u003e\n \u003cp\u003e18/10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.5845%;\"\u003e\n \u003cp\u003e15/13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10.5634%;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 36.2676%;\"\u003e\n \u003cp\u003eSubchondral BMD of medial femoral condyle, mg/cm\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.5845%;\"\u003e\n \u003cp\u003e263.87(238.37-289.36)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.5845%;\"\u003e\n \u003cp\u003e256.99(213.22-300.76)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10.5634%;\"\u003e\n \u003cp\u003e0.782\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 36.2676%;\"\u003e\n \u003cp\u003eMid-epiphyseal BMD of medial femoral condyle, mg/cm\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.5845%;\"\u003e\n \u003cp\u003e184.34(161.38-207.29)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.5845%;\"\u003e\n \u003cp\u003e166.30(134.56-198.04)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10.5634%;\"\u003e\n \u003cp\u003e0.350\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 36.2676%;\"\u003e\n \u003cp\u003eFemoral medial/lateral ratio\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.5845%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.5845%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10.5634%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 36.2676%;\"\u003e\n \u003cp\u003eSubchondral\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.5845%;\"\u003e\n \u003cp\u003e1.69(1.47-1.91)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.5845%;\"\u003e\n \u003cp\u003e1.86(1.46-2.26)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10.5634%;\"\u003e\n \u003cp\u003e0.449\u003csup\u003e\u0026nbsp;a\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 36.2676%;\"\u003e\n \u003cp\u003eMid-epphyseal\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.5845%;\"\u003e\n \u003cp\u003e1.64(1.43-1.86)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.5845%;\"\u003e\n \u003cp\u003e1.59(1.22-1.97)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10.5634%;\"\u003e\n \u003cp\u003e0.81\u003csup\u003e\u0026nbsp;a\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 36.2676%;\"\u003e\n \u003cp\u003eSubchondral BMD of medial tibial condyle, mg/cm\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.5845%;\"\u003e\n \u003cp\u003e194.38(162.26-226.49)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.5845%;\"\u003e\n \u003cp\u003e245.33(201.85-288.82)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10.5634%;\"\u003e\n \u003cp\u003e0.055\u003csup\u003e\u0026nbsp;b\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 36.2676%;\"\u003e\n \u003cp\u003eMid-epiphyseal BMD of medial femoral condyle, mg/cm\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.5845%;\"\u003e\n \u003cp\u003e140.35(115.69-165.00)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.5845%;\"\u003e\n \u003cp\u003e173.20(138.44-207.95)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10.5634%;\"\u003e\n \u003cp\u003e0.114\u003csup\u003e\u0026nbsp;b\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 36.2676%;\"\u003e\n \u003cp\u003eTibial medial/lateral ratio\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.5845%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.5845%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10.5634%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 36.2676%;\"\u003e\n \u003cp\u003eSubchondral\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.5845%;\"\u003e\n \u003cp\u003e1.47(1.22-1.72)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.5845%;\"\u003e\n \u003cp\u003e2.35(1.65-3.05)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10.5634%;\"\u003e\n \u003cp\u003e0.014\u003csup\u003e\u0026nbsp;a\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 36.2676%;\"\u003e\n \u003cp\u003eMid-epphyseal\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.5845%;\"\u003e\n \u003cp\u003e1.77(1.45-2.09)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.5845%;\"\u003e\n \u003cp\u003e3.91(2.15-5.67)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10.5634%;\"\u003e\n \u003cp\u003e0.02\u003csup\u003e\u0026nbsp;a\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 36.2676%;\"\u003e\n \u003cp\u003eFemoral osteonecrosis BMD, mg/cm\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.5845%;\"\u003e\n \u003cp\u003e63.9 (55.3-72.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26.5845%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10.5634%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003csup\u003ea\u003c/sup\u003eStudent\u0026rsquo;s t-test\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003csup\u003eb\u0026nbsp;\u003c/sup\u003eMann-Whitney test\u003c/p\u003e\n\u003cp\u003e\u003csup\u003ec\u0026nbsp;\u003c/sup\u003eLow BMD was defined as a T score of \u0026ndash;1 or less.\u003c/p\u003e\n\u003cp\u003eThe values showed in the table are given as mean number (95% CI).\u003c/p\u003e\n\u003cp\u003eSIFK, subchondral insufficiency fracture of knee; KOA, knee osteoarthritis; BMD, bone mineral density.\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"subchondral insufficiency fracture of knee, bone mineral density, quantitative computed tomography","lastPublishedDoi":"10.21203/rs.3.rs-6245969/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6245969/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cb\u003ePurpose\u003c/b\u003e\u003c/p\u003e \u003cp\u003eThe association between subchondral insufficiency fracture of knee (SIFK) and potential lower bone mineral density (BMD) were not clear and multifactorial. We tried to investigate their relevance by using the phantom-less quantitative computed tomography (QCT).\u003c/p\u003e\u003cp\u003e\u003cb\u003eMethods\u003c/b\u003e\u003c/p\u003e \u003cp\u003eWe collected bone mineral density (BMD) measurements from 32 cases diagnosed with SIFK and 28 control cases with osteoarthritis of the knee(KOA). All SIFK cases were gathered within two months of symptom onset and met the diagnostic criteria for magnetic resonance imaging. BMD measurements were conducted at the femoral neck and knee compartments. The medial-to-lateral (M-L) BMD ratios for the femoral and tibial medial compartments were compared between the two groups.\u003c/p\u003e\u003cp\u003e\u003cb\u003eResults\u003c/b\u003e\u003c/p\u003e \u003cp\u003eThe mean BMD values for the femoral neck and medial femoral regions showed no statistically significant difference between the SIFK cases and the KOA group. However, the mean tibial medial-to-lateral (M-L) ratios were statistically higher in the KOA group compared to those in the SIFK group, while the femoral M-L ratios remained statistically consistent between the two groups. The mean BMD in the osteonecrotic area was measured at 63.9 mg/cm\u0026sup3;, with all instances located within the femoral condyle.\u003c/p\u003e\u003cp\u003e\u003cb\u003eConclusion\u003c/b\u003e\u003c/p\u003e \u003cp\u003eOur findings do not support the hypothesis that SIFK are based on low bone mineral density, which was regard as a predictive factor in previous studies.\u003c/p\u003e","manuscriptTitle":"Low bone mineral density is not a predictive factor for subchondral insufficiency fracture of the knee, based on the analysis of QCT studies","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-04-02 07:12:42","doi":"10.21203/rs.3.rs-6245969/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"8b05bd99-10a2-4c56-89af-c104d2614d4b","owner":[],"postedDate":"April 2nd, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":46339353,"name":"Biological sciences/Biological techniques"},{"id":46339354,"name":"Biological sciences/Computational biology and bioinformatics"}],"tags":[],"updatedAt":"2025-04-25T04:08:41+00:00","versionOfRecord":[],"versionCreatedAt":"2025-04-02 07:12:42","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6245969","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6245969","identity":"rs-6245969","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}