Tibial bump in infants: A normal variant?

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Bryan Zuniga, Nicholas Lopez, Kirsten Simonton, Jonathan Samet This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6299648/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 07 Aug, 2025 Read the published version in Pediatric Radiology → Version 1 posted 13 You are reading this latest preprint version Abstract Background : Skeletal abnormalities are important to recognize in the workup of physical child abuse. Normal variants can simulate child abuse and cause incorrect diagnosis and management. An osseous protuberance of the proximal medial tibial metaphysis, “the tibial bump”, may represent a normal variant. Objective : To determine the prevalence of a tibial bump in infants undergoing a skeletal survey for child abuse and its association with traumatic findings. Materials and methods: A retrospective study of initial and follow-up child abuse skeletal surveys at a tertiary center was conducted to assess for the presence of a tibial bump on the proximal medial tibial metaphysis. The presence or absence of fracture healing changes around the tibial bump was recorded. Results : 21/261 cases showed a tibial bump on the initial skeletal survey. 14 of these 21 cases (66%) demonstrated a persistent tibial bump unchanged in appearance on the follow-up skeletal survey. None of the tibial bumps demonstrated findings of a healing fracture on the initial or follow-up skeletal survey. 10 (48%) had bilateral tibial bumps. The mean (median) age of a child with a tibial bump was 3.5 (2.8) months with a range from 1 to 8 months. Conclusion : A tibial bump on the proximal tibial metaphysis was a relatively common finding in infants undergoing workup for child abuse and not radiologically consistent with a fracture. It is likely a normal variant and should not be confused with a traumatic finding. Skeletal survey child abuse normal variant Figures Figure 1 Introduction Skeletal injuries are an important manifestation of child physical abuse, and accurate diagnosis is critical. Normal osseous variants can mimic fractures, resulting in mis-management and harm 1,2 . A subtle focal protuberance of the proximal medial tibial metaphyseal cortex, which the authors refer to as the “tibial bump,” may be encountered on radiographic images of children undergoing an occult injury evaluation for suspected physical abuse. The morphology of this finding can be mistaken for an acute buckle fracture or healing periosteal reaction. This finding was briefly mentioned as a likely normal variant related to focal physiologic periosteal reaction by Kleinman et al and termed proximal cortical irregularity 3,4 . However, no known systematic studies have been performed to assess the prevalence of this finding in an infant population undergoing evaluation for physical abuse or to determine whether it represents a traumatic injury. Establishing this finding as a non-traumatic normal variant would help radiologists avoid additional diagnostic studies and prevent unnecessary abuse reporting 2 . It is recommended in young children with physical abuse concerns to undergo both an initial skeletal survey and follow-up skeletal survey around two weeks after initial evaluation 5-9 . The aim of this study is to determine the prevalence of the tibial bump in young infants who underwent initial and follow-up skeletal surveys as part of possible physical abuse evaluation and describe any changes or evolution of this finding on subsequent imaging. Our hypothesis is that the tibial bump is a normal variant rather than a traumatic injury, and not uncommonly seen on infant skeletal surveys. Methods This was a retrospective study at our academic tertiary care level 1 trauma children’s hospital. The study was approved by the hospital’s institutional review board (IRB) and a full waiver of HIPAA authorization was granted. A password protected REDCap clinical database was used to identify study subjects. The database is maintained by the child abuse pediatrics division to collect medical information on child physical abuse consults. Cases were included in this study if they were less than 12 months old, being evaluated for physical abuse between 2017-2022, and underwent both an initial skeletal survey as well as follow-up skeletal survey approximately two weeks after initial survey. Cases were excluded if there wasn’t both an initial and follow-up skeletal survey, if the patient was older than 12 months upon initial presentation, or if the skeletal survey was not part of a child abuse evaluation. Cases that met study criteria were included regardless of medical history or any prior diagnoses. Data extracted included age, sex, race, ethnicity and documentation on completion of the initial and follow-up skeletal surveys. The cases were all reviewed and consensus reached by a pediatric radiology fellow and pediatric musculoskeletal radiologist with 9 years experience. The study team radiologists were blinded to any specific history, but knew that the skeletal surveys were being performed for child abuse workup. After the images were reviewed and consensus reached, the original reports were viewed for mention of any abnormality in the region of the proximal medial tibia. The tibial bump was defined as a focal smooth protuberance of cortex at the proximal medial tibial metaphysis, similar to what a radiologist might normally call a subtle buckle fracture (Fig. 1). On the standard skeletal survey at our institution, the tibia and fibula are imaged with a single field of view from knee to ankle (Fig. 1a). Occasionally, the tibial metpaphysis can also be seen on the view of the ipsilateral femur. At the time of the study, no lateral or oblique images were performed of the tibia in our protocol. The proximal tibial metaphysis of the right and left leg were evaluated for the presence of the tibial bump. The presence or absence of the tibial bump was then evaluated on the follow-up skeletal survey. The surrounding bone was assessed for findings of a healing fracture such as periosteal reaction or sclerosis. Results In total, 261 cases met the inclusion criteria, representing 259 unique patients. 21 cases (8%) demonstrated a tibial bump on the initial skeletal survey, and 14 of these 21 cases (66%) demonstrated a persistent tibial bump unchanged in appearance on the follow-up skeletal survey. None of the tibial bumps demonstrated findings of a healing fracture on the initial or follow-up skeletal survey. Of the 21 cases that demonstrated tibial bumps on the initial skeletal survey 10 (48%) cases demonstrated bilateral bumps. On follow up skeletal survey of the initial cases with bilateral tibial bumps, 4 of 10 redemonstrated bilateral bumps and in 2 of 10, only unilateral bumps were seen. The mean (median) age of a child with a tibial bump was 3.5 (2.8) months with a range from 1 to 8 months (Table 1). Of the 14 cases with unchanged tibial bumps from initial to follow-up skeletal surveys, 7 (50%) were bilateral. Including cases with bilateral tibial bumps, there were 31 total tibial bumps on the initial skeletal survey and 18 total tibial bumps on the follow-up skeletal survey. To estimate the prevalence of the tibial bump in our study, we only considered the number of cases with a tibial bump on the initial skeletal survey. A case counted as one incidence whether a patient had a unilateral or bilateral tibial bumps. Therefore, the prevalence of at least one tibial bump in our study is 21/261 (8%). Original radiology reports of the initial skeletal survey were reviewed for the 21 cases in our study with an identified tibial bump. Of the 21 cases, two original radiology reports questioned this finding as a fracture, one questioned this finding as a normal variant, and the remaining 17 reports did not mention the finding. Discussion The tibial bump was a finding seen on skeletal surveys of infants being assessed for child abuse, with a prevalence of 8% in our study. It was bilateral in 48% of cases in our study, while reported to be seen in 25% of cases by Kleinman et al 3 . No tibial bump demonstrated signs of a healing fracture on initial or follow-up imaging. The bump was unchanged when seen on the follow-up skeletal survey, which further argues against a fracture. One could argue that if a bump was seen on the initial film and not on the follow-up, then it was a fracture that completed healing. But if the tibial bump is a fracture, then there would likely be cases with more extensive periosteal or medullary sclerosis, though this was not the case in our study. Therefore, the authors conclude based on our study that the tibial bump is more likely to be a normal variant and not a traumatic injury. As shown in our study, the tibial bump could be confused with a buckle fracture, which may have significant implications in the evaluation and diagnostic decision making of child physical abuse. The inconsistent presence of the tibial bump on the follow-up skeletal survey is likely related to projectional radiographic differences, as it is a subtle finding. Kleinman et al stated the proximal tibial metaphyseal irregularity could be related to physiologic periosteal reaction 3 . It is interesting to note that the time frame of the tibial bump seen in our study coincides with that of physiologic subperiosteal new bone formation. For example, the tibial bump occurred at a mean age of 3.5 months (range: 1 to 8 months), following the pattern of physiologic subperiosteal new bone formation that peaks at 2-3 months of age, and disappears after 6 months 10 . The bump may be alternatively be related to developing attachment sites around the knee as well, but this is unknown. Conclusions The tibial bump on the medial proximal tibial metaphysis in infants is a relatively common finding seen on skeletal surveys among children undergoing a child physical abuse evaluation. When analyzing initial and follow-up skeletal surveys, the tibial bump did not demonstrate changes associated with a healing fracture. The finding is likely a normal variant that should not be confused with a fracture. Declarations Ethics Declarations All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. As the study was retrospective, we received a full waiver of HIPAA Authorization for the use and disclosure of protected health information for studies involving minimal risk to the privacy of individuals. The human ethics and consent to participate was therefore not applicable. The study was approved by the hospital’s official internal review board (IRB). References Marine MB, Forbes-Amrhein MM. Fractures of child abuse. Pediatric radiology. 2021;51(6):1003-1013. Brown SD. Ethical challenges in child abuse: what is the harm of a misdiagnosis? Pediatric radiology. 2021;51(6):1070-1075. Kleinman PK, Belanger PL, Karellas A, Spevak MR. Normal metaphyseal radiologic variants not to be confused with findings of infant abuse. AJR American journal of roentgenology. 1991;156(4):781-783. Quigley AJ, Stafrace S. Skeletal survey normal variants, artefacts and commonly misinterpreted findings not to be confused with non-accidental injury. Pediatric radiology. 2014;44:82-93. Flaherty EG, Perez-Rossello JM, Levine MA, et al. Evaluating children with fractures for child physical abuse. Pediatrics. 2014;133(2):e477-e489. Bennett CE, Christian CW. Clinical evaluation and management of children with suspected physical abuse. Pediatric radiology. 2021;51(6):853-860. Harper NS, Lewis T, Eddleman S, Lindberg DM, Investigators E. Follow-up skeletal survey use by child abuse pediatricians. Child Abuse & Neglect. 2016;51:336-342. Harper NS, Eddleman S, Lindberg DM, Investigators E. The utility of follow-up skeletal surveys in child abuse. Pediatrics. 2013;131(3):e672-e678. Christian CW, Abuse CoC, Neglect. The evaluation of suspected child physical abuse. Pediatrics. 2015;135(5):e20150356. Kwon DS, Spevak MR, Fletcher K, Kleinman PK. Physiologic subperiosteal new bone formation: prevalence, distribution, and thickness in neonates and infants. American Journal of Roentgenology. 2002;179(4):985-988. Table Table 1 is available in the Supplementary Files section. Additional Declarations No competing interests reported. Supplementary Files Table1.docx Cite Share Download PDF Status: Published Journal Publication published 07 Aug, 2025 Read the published version in Pediatric Radiology → Version 1 posted Editorial decision: Revision requested 02 May, 2025 Reviews received at journal 21 Apr, 2025 Reviews received at journal 20 Apr, 2025 Reviews received at journal 17 Apr, 2025 Reviews received at journal 15 Apr, 2025 Reviewers agreed at journal 10 Apr, 2025 Reviewers agreed at journal 06 Apr, 2025 Reviewers agreed at journal 05 Apr, 2025 Reviewers agreed at journal 03 Apr, 2025 Reviewers invited by journal 02 Apr, 2025 Editor assigned by journal 26 Mar, 2025 Submission checks completed at journal 26 Mar, 2025 First submitted to journal 24 Mar, 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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The tibial bump is at the proximal medial tibial metaphysis (arrow).\u003c/p\u003e\n\u003cp\u003eb: Initial skeletal survey radiograph of a 3 month old female patient demonstrating the tibial bump (arrow).\u003c/p\u003e\n\u003cp\u003ec: \u0026nbsp;Follow up skeletal survey radiograph of a 3 month old female patient showing the tibial bump (arrow) without significant change or evidence of a healing fracture.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-6299648/v1/4b5836b02fd4e213a9421002.png"},{"id":88814235,"identity":"970e56a6-d989-45e4-a91d-84de3b70b09c","added_by":"auto","created_at":"2025-08-11 16:08:53","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":868099,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6299648/v1/d422ae40-0ff1-4a95-88d8-4708167ccf11.pdf"},{"id":81931432,"identity":"dae88736-fd48-4e49-82b6-4d0c5ac263c4","added_by":"auto","created_at":"2025-05-05 05:29:31","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":17879,"visible":true,"origin":"","legend":"","description":"","filename":"Table1.docx","url":"https://assets-eu.researchsquare.com/files/rs-6299648/v1/b8c75f69a07540f7e47d626c.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Tibial bump in infants: A normal variant?","fulltext":[{"header":"Introduction","content":"\u003cp\u003eSkeletal injuries are an important manifestation of child physical abuse, and accurate diagnosis is critical. Normal osseous variants can mimic fractures, resulting in mis-management and harm\u003csup\u003e1,2\u003c/sup\u003e. A subtle focal protuberance of the proximal medial tibial metaphyseal cortex, which the authors refer to as the \u0026ldquo;tibial bump,\u0026rdquo; may be encountered on radiographic images of children undergoing an occult injury evaluation for suspected physical abuse. The morphology of this finding can be mistaken for an acute buckle fracture or healing periosteal reaction. This finding was briefly mentioned as a likely normal variant related to focal physiologic periosteal reaction by Kleinman et al and termed proximal cortical irregularity\u003csup\u003e3,4\u003c/sup\u003e. However, no known systematic studies have been performed to assess the prevalence of this finding in an infant population undergoing evaluation for physical abuse or to determine whether it represents a traumatic injury. Establishing this finding as a non-traumatic normal variant would help radiologists avoid additional diagnostic studies and prevent unnecessary abuse reporting\u003csup\u003e2\u003c/sup\u003e.\u003c/p\u003e\n\u003cp\u003eIt is recommended in young children with physical abuse concerns to undergo both an initial skeletal survey and follow-up skeletal survey around two weeks after initial evaluation\u003csup\u003e5-9\u003c/sup\u003e. The aim of this study is to determine the prevalence of the tibial bump in young infants who underwent initial and follow-up skeletal surveys as part of possible physical abuse evaluation and describe any changes or evolution of this finding on subsequent imaging.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eOur hypothesis is that the tibial bump is a normal variant rather than a traumatic injury, and not uncommonly seen on infant skeletal surveys. \u0026nbsp;\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003eThis was a retrospective study at our academic tertiary care level 1 trauma children\u0026rsquo;s hospital. The study was approved by the hospital\u0026rsquo;s institutional review board (IRB) and a full waiver of HIPAA authorization was granted. A password protected REDCap clinical database was used to identify study subjects. The database is maintained by the child abuse pediatrics division to collect medical information on child physical abuse consults. Cases were included in this study if they were less than 12 months old, being evaluated for physical abuse between 2017-2022,\u0026nbsp;and underwent both an initial skeletal survey as well as follow-up skeletal survey approximately two weeks after initial survey. Cases were excluded if there wasn\u0026rsquo;t both an initial and follow-up skeletal survey, if the patient was older than 12 months upon initial presentation, or if the skeletal survey was not part of a child abuse evaluation.\u0026nbsp;Cases that met study criteria were included regardless of medical history or any prior diagnoses. Data extracted included age, sex, race, ethnicity and documentation on completion of the initial and follow-up skeletal surveys.\u0026nbsp;The cases were all reviewed and consensus reached by a pediatric radiology fellow and pediatric musculoskeletal radiologist with 9 years experience. The study team radiologists were blinded to any specific history, but knew that the skeletal surveys were being performed for child abuse workup. After the images were reviewed and consensus reached, the original reports were viewed for mention of any abnormality in the region of the proximal medial tibia.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe tibial bump was defined as a focal smooth protuberance of cortex at the proximal medial tibial metaphysis, similar to what a radiologist might normally call a subtle buckle fracture (Fig. 1). On the standard skeletal survey at our institution, the tibia and fibula are imaged with a single field of view from knee to ankle (Fig. 1a). Occasionally, the tibial metpaphysis can also be seen on the view of the ipsilateral femur. At the time of the study, no lateral or oblique images were performed of the tibia in our protocol. The proximal tibial metaphysis of the right and left leg were evaluated for the presence of the tibial bump. The presence or absence of the tibial bump was then evaluated on the follow-up skeletal survey. The surrounding bone was assessed for findings of a healing fracture such as periosteal reaction or sclerosis. \u0026nbsp; \u0026nbsp;\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eIn total, 261 cases met the inclusion criteria, representing 259 unique patients. 21 cases (8%) demonstrated a tibial bump on the initial skeletal survey, and 14 of these 21 cases (66%) demonstrated a persistent tibial bump unchanged in appearance on the follow-up skeletal survey. None of the tibial bumps demonstrated findings of a healing fracture on the initial or follow-up skeletal survey. Of the 21 cases that demonstrated tibial bumps on the initial skeletal survey 10 (48%) cases demonstrated bilateral bumps. On follow up skeletal survey of the initial cases with bilateral tibial bumps, 4 of 10 redemonstrated bilateral bumps and in 2 of 10, only unilateral bumps were seen.\u003c/p\u003e\n\u003cp\u003eThe mean (median) age of a child with a tibial bump was 3.5 (2.8) months with a range from 1 to 8 months (Table 1). Of the 14 cases with unchanged tibial bumps from initial to follow-up skeletal surveys, 7 (50%) were bilateral. Including cases with bilateral tibial bumps, there were 31 total tibial bumps on the initial skeletal survey and 18 total tibial bumps on the follow-up skeletal survey. To estimate the prevalence of the tibial bump in our study, we only considered the number of cases with a tibial bump on the initial skeletal survey. A case counted as one incidence whether a patient had a unilateral or bilateral tibial bumps. Therefore, the prevalence of at least one tibial bump in our study is 21/261 (8%).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eOriginal radiology reports of the initial skeletal survey were reviewed for the 21 cases in our study with an identified tibial bump. Of the 21 cases, two original radiology reports questioned this finding as a fracture, one questioned this finding as a normal variant, and the remaining 17 reports did not mention the finding.\u0026nbsp;\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe tibial bump was a finding seen on skeletal surveys of infants being assessed for child abuse, with a prevalence of 8% in our study. It was bilateral in 48% of cases in our study, while reported to be seen in 25% of cases by Kleinman et al\u003csup\u003e3\u003c/sup\u003e. No tibial bump demonstrated signs of a healing fracture on initial or follow-up imaging. The bump was unchanged when seen on the follow-up skeletal survey, which further argues against a fracture. One could argue that if a bump was seen on the initial film and not on the follow-up, then it was a fracture that completed healing. But if the tibial bump is a fracture, then there would likely be cases with more extensive periosteal or medullary sclerosis, though this was not the case in our study. \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTherefore, the authors conclude based on our study that the tibial bump is more likely to be a normal variant and not a traumatic injury. As shown in our study, the tibial bump could be confused with a buckle fracture, which may have significant implications in the evaluation and diagnostic decision making of child physical abuse. The inconsistent presence of the tibial bump on the follow-up skeletal survey is likely related to projectional radiographic differences, as it is a subtle finding. Kleinman et al stated the proximal tibial metaphyseal irregularity could be related to physiologic periosteal reaction\u003csup\u003e3\u003c/sup\u003e. It is interesting to note that the time frame of the tibial bump seen in our study coincides with that of physiologic subperiosteal new bone formation. For example, the tibial bump occurred at a mean age of 3.5 months (range: 1 to 8 months), following the pattern of physiologic subperiosteal new bone formation that peaks at 2-3 months of age, and disappears after 6 months\u003csup\u003e10\u003c/sup\u003e. \u0026nbsp;The bump may be alternatively be related to developing attachment sites around the knee as well, but this is unknown.\u0026nbsp;\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eThe tibial bump on the medial proximal tibial metaphysis in infants is a relatively common finding seen on skeletal surveys among children undergoing a child physical abuse evaluation. When analyzing initial and follow-up skeletal surveys, the tibial bump did not demonstrate changes associated with a healing fracture. The finding is likely a normal variant that should not be confused with a fracture.\u0026nbsp;\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics Declarations\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.\u003c/p\u003e\n\u003cp\u003eAs the study was retrospective, we received a full waiver of HIPAA Authorization for the use and disclosure of protected health information for studies involving minimal risk to the privacy of individuals. The human ethics and consent to participate was therefore not applicable. The study was approved by the hospital\u0026rsquo;s official internal review board (IRB).\u0026nbsp;\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eMarine MB, Forbes-Amrhein MM. Fractures of child abuse. \u003cem\u003ePediatric radiology. \u003c/em\u003e2021;51(6):1003-1013.\u003c/li\u003e\n\u003cli\u003eBrown SD. Ethical challenges in child abuse: what is the harm of a misdiagnosis? \u003cem\u003ePediatric radiology. \u003c/em\u003e2021;51(6):1070-1075.\u003c/li\u003e\n\u003cli\u003eKleinman PK, Belanger PL, Karellas A, Spevak MR. Normal metaphyseal radiologic variants not to be confused with findings of infant abuse. \u003cem\u003eAJR American journal of roentgenology. \u003c/em\u003e1991;156(4):781-783.\u003c/li\u003e\n\u003cli\u003eQuigley AJ, Stafrace S. Skeletal survey normal variants, artefacts and commonly misinterpreted findings not to be confused with non-accidental injury. \u003cem\u003ePediatric radiology. \u003c/em\u003e2014;44:82-93.\u003c/li\u003e\n\u003cli\u003eFlaherty EG, Perez-Rossello JM, Levine MA, et al. Evaluating children with fractures for child physical abuse. \u003cem\u003ePediatrics. \u003c/em\u003e2014;133(2):e477-e489.\u003c/li\u003e\n\u003cli\u003eBennett CE, Christian CW. Clinical evaluation and management of children with suspected physical abuse. \u003cem\u003ePediatric radiology. \u003c/em\u003e2021;51(6):853-860.\u003c/li\u003e\n\u003cli\u003eHarper NS, Lewis T, Eddleman S, Lindberg DM, Investigators E. Follow-up skeletal survey use by child abuse pediatricians. \u003cem\u003eChild Abuse \u0026amp; Neglect. \u003c/em\u003e2016;51:336-342.\u003c/li\u003e\n\u003cli\u003eHarper NS, Eddleman S, Lindberg DM, Investigators E. The utility of follow-up skeletal surveys in child abuse. \u003cem\u003ePediatrics. \u003c/em\u003e2013;131(3):e672-e678.\u003c/li\u003e\n\u003cli\u003eChristian CW, Abuse CoC, Neglect. The evaluation of suspected child physical abuse. \u003cem\u003ePediatrics. \u003c/em\u003e2015;135(5):e20150356.\u003c/li\u003e\n\u003cli\u003eKwon DS, Spevak MR, Fletcher K, Kleinman PK. Physiologic subperiosteal new bone formation: prevalence, distribution, and thickness in neonates and infants. \u003cem\u003eAmerican Journal of Roentgenology. \u003c/em\u003e2002;179(4):985-988.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Table","content":"\u003cp\u003eTable 1 is available in the Supplementary Files section.\u003c/p\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":"Skeletal survey, child abuse, normal variant","lastPublishedDoi":"10.21203/rs.3.rs-6299648/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6299648/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground\u003c/strong\u003e: Skeletal abnormalities are important to recognize in the workup of physical child abuse. Normal variants can simulate child abuse and cause incorrect diagnosis and management. An osseous protuberance of the proximal medial tibial metaphysis, “the tibial bump”, may represent a normal variant.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eObjective\u003c/strong\u003e: To determine the prevalence of a tibial bump in infants undergoing a skeletal survey for child abuse and its association with traumatic findings.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMaterials and methods:\u003c/strong\u003e A retrospective study of initial and follow-up child abuse skeletal surveys at a tertiary center was conducted to assess for the presence of a tibial bump on the proximal medial tibial metaphysis. The presence or absence of fracture healing changes around the tibial bump was recorded.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults\u003c/strong\u003e: 21/261 cases showed a tibial bump on the initial skeletal survey. 14 of these 21 cases (66%) demonstrated a persistent tibial bump unchanged in appearance on the follow-up skeletal survey. None of the tibial bumps demonstrated findings of a healing fracture on the initial or follow-up skeletal survey. 10 (48%) had bilateral tibial bumps. The mean (median) age of a child with a tibial bump was 3.5 (2.8) months with a range from 1 to 8 months.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion\u003c/strong\u003e: A tibial bump on the proximal tibial metaphysis was a relatively common finding in infants undergoing workup for child abuse and not radiologically consistent with a fracture. It is likely a normal variant and should not be confused with a traumatic finding.\u003c/p\u003e","manuscriptTitle":"Tibial bump in infants: A normal variant?","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-05-05 05:29:26","doi":"10.21203/rs.3.rs-6299648/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-05-02T23:21:27+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-04-21T17:14:26+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-04-20T12:41:49+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-04-17T17:16:40+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-04-15T21:13:57+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"12358476802586322518568671756631709730","date":"2025-04-10T18:55:30+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"184292734819278907387731530544128739976","date":"2025-04-06T09:28:05+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"325916309101520795275534308939705360264","date":"2025-04-06T02:01:57+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"158257392913963681413718825194450992100","date":"2025-04-03T23:58:29+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-04-02T15:12:56+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-03-27T00:42:44+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-03-27T00:42:19+00:00","index":"","fulltext":""},{"type":"submitted","content":"Pediatric Radiology","date":"2025-03-25T03:28:42+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":"e26dc510-5725-4a94-9d08-2bf6893cab48","owner":[],"postedDate":"May 5th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-08-11T16:05:40+00:00","versionOfRecord":{"articleIdentity":"rs-6299648","link":"https://doi.org/10.1007/s00247-025-06361-9","journal":{"identity":"pediatric-radiology","isVorOnly":false,"title":"Pediatric Radiology"},"publishedOn":"2025-08-07 15:57:38","publishedOnDateReadable":"August 7th, 2025"},"versionCreatedAt":"2025-05-05 05:29:26","video":"","vorDoi":"10.1007/s00247-025-06361-9","vorDoiUrl":"https://doi.org/10.1007/s00247-025-06361-9","workflowStages":[]},"version":"v1","identity":"rs-6299648","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6299648","identity":"rs-6299648","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}