Classic Metaphyseal Lesions Research Articles

Improving the radiographic image analysis of the classic metaphyseal lesion via conditional diffusion models

The classic metaphyseal lesion (CML) is a unique fracture highly specific for infant abuse. This fracture is often subtle in radiographic appearance and commonly occurs in the distal tibia. The development of an automated model that can accurately identify distal tibial radiographs with CMLs is important to assist radiologists in detecting these fractures. However, building such a model typically requires a large and diverse training dataset. To address this problem, we propose a novel diffusion model for data augmentation called masked conditional diffusion model (MaC-DM). In contrast to previous generative models, our approach produces a wide range of realistic-appearing synthetic images of distal tibial radiographs along with their associated segmentation masks. MaC-DM achieves this by incorporating weighted segmentation masks of the distal tibias and CML fracture sites as image conditions for guidance. The augmented images produced by MaC-DM significantly enhance the performance of various commonly used classification models, accurately distinguishing normal distal tibial radiographs from those with CMLs. Additionally, it substantially improves the performance of different segmentation models, accurately labeling areas of the CMLs on distal tibial radiographs. Furthermore, MaC-DM can control the size of the CML fracture in the augmented images.

Deep generative model of the distal tibial classic metaphyseal lesion in infants: assessment of synthetic images.

The classic metaphyseal lesion (CML) is a distinctive fracture highly specific to infant abuse. To increase the size and diversity of the training CML database for automated deep-learning detection of this fracture, we developed a mask conditional diffusion model (MaC-DM) to generate synthetic images with and without CMLs. To objectively and subjectively assess the synthetic radiographic images with and without CMLs generated by MaC-DM. For retrospective testing, we randomly chose 100 real images (50 normals and 50 with CMLs; 39 infants, male = 22, female = 17; mean age = 4.1 months; SD = 3.1 months) from an existing distal tibia dataset (177 normal, 73 with CMLs), and generated 100 synthetic distal tibia images via MaC-DM (50 normals and 50 with CMLs). These test images were shown to 3 blinded radiologists. In the first session, radiologists determined if the images were normal or had CMLs. In the second session, they determined if the images were real or synthetic. We analyzed the radiologists' interpretations and employed t-distributed stochastic neighbor embedding technique to analyze the data distribution of the test images. When presented with the 200 images (100 synthetic, 100 with CMLs), radiologists reliably and accurately diagnosed CMLs (kappa = 0.90, 95% CI = [0.88-0.92]; accuracy = 92%, 95% CI = [89-97]). However, they were inaccurate in differentiating between real and synthetic images (kappa = 0.05, 95% CI = [0.03-0.07]; accuracy = 53%, 95% CI = [49-59]). The t-distributed stochastic neighbor embedding analysis showed substantial differences in the data distribution between normal images and those with CMLs (area under the curve = 0.996, 95% CI = [0.992-1.000], P < .01), but minor differences between real and synthetic images (area under the curve = 0.566, 95% CI = [0.486-0.647], P = .11). Radiologists accurately diagnosed images with distal tibial CMLs but were unable to distinguish real from synthetically generated ones, indicating that our generative model could synthesize realistic images. Thus, MaC-DM holds promise as an effective strategy for data augmentation in training machine-learning models for diagnosis of distal tibial CMLs.

Diagnosis of metaphyseal fractures in infants and young children with suspected inflicted injury: a systematic review of cross-sectional imaging techniques

To compare the diagnostic accuracy, advantages, and disadvantages of different medical imaging techniques for detecting metaphyseal fractures (also known as classic metaphyseal lesions [CMLs]) in infants and young children with suspected inflicted trauma. This systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) checklist and Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool criteria. Predefined keywords were used to search online databases for English articles published between 1 January 1980 and 31 March 2023. The initial search revealed 83 studies, only five of which met the inclusion criteria. The sensitivity and specificity of positron-emission tomography (PET) were 67% and 99%, respectively. The sensitivity and specificity of ultrasound were 55-61% and 96-97%, respectively. The sensitivity of magnetic resonance imaging (MRI) whole-body screening was 31%. The sensitivity of bone scintigraphy was 17% in one and 35% in a second study. Computed tomography was not used to detect CMLs in any diagnostic accuracy study. This systematic review has identified only a small number of relevant studies. In addition to the skeletal survey, PET and ultrasound may be helpful for the diagnosis of CMLs in infants and young children with suspected abuse; however, ultrasound has greater potential than PET due to its higher specificity, lack of radiation exposure, low cost, and wider availability.

Yield of Postmortem Skeletal Surveys in Infants Presenting to Emergency Care With Sudden and Unexpected Death.

Child abuse should be considered in cases of sudden unexpected infant death (SUID). Postmortem skeletal surveys (PM-SS) are recommended to evaluate for abusive fractures in SUID. Little is known about the yield of PM-SS among infants presenting to emergency care with SUID. Our objectives were to (1) describe the presentation and care of infants with SUID at a tertiary children's hospital emergency department and (2) report PM-SS use and findings. We performed a retrospective study of infants younger than 12 months with SUID presenting to an urban emergency department from 2007 to 2019. We describe their presentation and care, including PM-SS performance and findings, referrals to the medical examiner, and reports to child protective services (CPS). We assessed for associations between race, payer, and presentation with reports to CPS. Of 73 infants with SUID, concern for unsafe sleep was documented in 45 (61.6%) and 71 (97.3%) underwent cardiopulmonary resuscitation by a medical professional. All 73 (100%) underwent PM-SS and were referred to the medical examiner. Twelve definite fractures (11 rib, 1 classic metaphyseal lesion) and 8 possible fractures (7 rib, 1 classic metaphyseal lesion) were identified among 6 (8.2%) infants. Forty-three (58.9%) were reported to CPS. There were no associations between race, payer, age, or history of unsafe sleep and CPS reports. One in 12 cases of SUID had a possible and/or definite fracture identified on plain radiography. Multicenter studies are needed to compare yield across different postmortem imaging modalities and populations.

Machine learning to identify distal tibial classic metaphyseal lesions of infant abuse: a pilot study.

The classic metaphyseal lesion (CML) is an injury that is highly specific for infant abuse, and the distal tibia is one of the most common sites of occurrence. A machine learning tool that identifies distal tibial CMLs on infant skeletal surveys could assist radiologists in the diagnosis of infant abuse. To develop and evaluate a machine learning-based classification algorithm to identify distal tibial CMLs on skeletal surveys performed for suspected infant abuse. We reviewed medical records of infants (≤1year old) who had skeletal surveys for suspected abuse at a large tertiary children's hospital over the past 13years to identify those at low and high risk for abuse. Normal distal tibial radiographs from the low-risk group formed the normal study cohort; radiographs with distal tibial CMLs from the high-risk group formed the abnormal study cohort. We used these two cohorts to train a machine learning algorithm to classify distal tibial radiographs as normal or abnormal. We systematically evaluated this algorithm using a fivefold cross-validation procedure and statistically analyzed the results. The normal study cohort consisted of 177 radiographs from 89 infants, and the abnormal study cohort consisted of 73 radiographs from 35 infants. Our machine learning algorithm showed an overall performance accuracy of 93% and Kappa of 0.84. The overall sensitivity and specificity of the model were 88% and 96%, respectively. Our developed machine learning model shows encouraging results as an automated tool to identify CMLs of the distal tibia on skeletal surveys performed for suspected infant abuse.

Fractures and skin lesions in pediatric abusive head trauma: a forensic multi-center study

Abusive head trauma (AHT) and its most common variant, the shaken baby syndrome (SBS), are predominantly characterized by central nervous system-associated lesions. Relatively little data are available on the value of skeletal and skin injuries for the diagnosis of SBS or AHT. Thus, the present study retrospectively investigated 72 cases of living children diagnosed with the explicit diagnosis of SBS during medico-legal examinations at three German university institutes of legal medicine. The risk of circular reasoning was reduced by the presence of 15 cases with confession by perpetrators. Accordingly, the comparison with the 57 non-confession cases yielded no significant differences. Skeletal survey by conventional projection radiography, often incomplete, was found to be performed in 78% of the cases only. Fractures were found in 32% of the cases. The skull (43%) and ribs (48%) were affected most frequently; only 8% of the cases showed classic metaphyseal lesions. In 48% of the cases, healing fractures were present. Skin lesions (hematomas and abrasions) were found in 53% of the cases with the face (76%), scalp (26%), and trunk (50%) being the major sites. In 48% of the cases, healing skin lesions were observed. Nearly 80% of the cases with fractures also showed skin lesions. The data prove that SBS is frequently accompanied by other forms of physical abuse. Therefore, skeletal survey is indispensable and should always be done completely and according to existing imaging guidelines if child abuse is suspected.

Guideline adherence and quality assurance in radiological diagnostics in cases of suspected child abuse in Germany

HintergrundDie bildgebende Diagnostik nimmt in der Evaluation nichtakzidentieller Verletzungsfolgen im Kindesalter eine Schlüsselrolle ein. Frakturen sind nach Hautläsionen wie Abschürfungen oder Hämatomen die zweithäufigste Folge körperlicher Kindesmisshandlung. Mit Hilfe radiologischer Kriterien können nichtakzidentielle von akzidentiellen Frakturen differenziert werden. Spezielle Frakturtypen wie die klassische metaphysäre Läsion können nur bei hoher Bildqualität differenziert werden.FragestellungIn einer prospektiven Analyse sollten Leitlinientreue und Qualitätssicherung der radiologischen Diagnostik bei Misshandlungsverdacht in Deutschland erfasst werden. Dazu wurden Quantität und diagnostische Qualität in der universitären und nichtuniversitären Versorgung sowie in Abhängigkeit einer vorhandenen kinderradiologischen Fachabteilung analysiert.Material und MethodenEs wurden 958 Röntgenuntersuchungen von 114 vermuteten Misshandlungsfällen (46 Mädchen, 68 Jungen) bewertet. Insgesamt 42 Fälle aus universitären, 42 aus maximalversorgenden und 30 aus regelversorgenden Kliniken mit einem medianen Alter von 6 Monaten (3 Wochen – 3. Lebensjahr) wurden als DICOM-Daten von 3 Kinderradiologen im Konsensverfahren hinsichtlich Leitlinientreue und verschiedener Qualitätsparameter beurteilt. Ein Begleitfragebogen sollte die theoretischen Kenntnisse mit der jeweiligen praktischen Umsetzung vergleichen.ErgebnisseJe Fall wurden im Mittel 8,4 Röntgenaufnahmen (1–22) angefertigt. In 12 von 114 beurteilten Fällen (10 %) lag ein vollständiger Skelettstatus nach S1-Leitlinie GPR vor. In 13 Fällen (10,5 %) wurde ein Babygramm durchgeführt. Abteilungen mit kinderradiologischem Schwerpunkt fertigten signifikant mehr Röntgenaufnahmen je Skelettstatus an als Einrichtungen ohne Schwerpunkt (p < 0,05). Eine signifikant höhere qualitative Umsetzung wurde in Universitätskliniken verzeichnet (p < 0,001). Eine Übereinstimmung von Fragebogenantwort und vorliegendem Bildmaterial zeigte sich unabhängig der Institutionsart nur marginal.DiskussionIn Deutschland fehlt bislang mehrheitlich ein leitliniengerechtes Vorgehen bei Misshandlungsverdacht. Es bleibt abzuwarten, ob sich dies mit der breiteren Implementierung von Kinderschutzgruppen und der 2019 verabschiedeten S3-Kinderschutzleitlinie (AWMF-Registrierungsnummer: 027-069) zukünftig ändern wird. Die Etablierung von Referenzzentren für Zweitbefundung und Empfehlungen zur Aufnahmetechnik können zusätzlich die Versorgungsqualität nachhaltig verbessern.

Accuracy of ultrasound in the diagnosis of classic metaphyseal lesions using radiographs as the gold standard.

Diagnosis of classic metaphyseal lesions (CMLs) in children suspected for child abuse can be challenging. Ultrasound (US) can potentially help diagnose CMLs. However, its accuracy is unknown. To evaluate the accuracy of US in the diagnosis of CMLs using skeletal survey reports as the gold standard. US of the metaphysis was performed in three patient groups age <1year. Informed consent was obtained for patients scheduled for renal US (Group 1) and for patients scheduled for skeletal surveys for possible child abuse (Group 2). Targeted US was also performed in selected patients to evaluate for possible CML suspected on radiographs (Group 3). In Groups 1 and 2, US was performed of both distal femurs, and of either the right or left proximal and distal tibia. Two radiologists (Rad1 and Rad2) independently reviewed the US studies, blinded to history and other imaging. US sensitivity and specificity were calculated using the following gold standards: CML definitely seen on skeletal survey (positive), CML definitely not seen on skeletal survey or part of renal US group (negative). Cases where the skeletal survey was indeterminate for CML were excluded. Kappa statistics were used to evaluate interobserver variability. Two hundred forty-one metaphyseal sites were evaluated by US in 63 children (mean age: 5months; 33 males); 34 had skeletal surveys and 29 had renal US. Kappa for the presence of CML was 0.70 with 95.7% agreement. US sensitivity was 55.0% and 63.2% and the specificity was 97.7% and 96.7% for Rad1 and Rad2, respectively. US has low sensitivity and high specificity in CML diagnosis. Thus, negative US does not exclude CML, but when the radiographs are equivocal, positive US can help substantiate the diagnosis.

Establishing signs for acute and healing phases of distal tibial classic metaphyseal lesions.

Stages of healing for classic metaphyseal lesions (CMLs) are not well established. Follow-up skeletal surveys provide an opportunity to evaluate signs of healing CMLs. To evaluate the sequence of CML healing phases by comparing initial and follow-up skeletal surveys in children with distal tibial CMLs on the initial survey. Findings could assist in child abuse investigations. We identified all distal tibia CMLs with initial and follow-up skeletal surveys performed January 2009 through December 2018 at our institution. Two pediatric radiologists reviewed the surveys using Likert score from 1 (no CML) to 5 (definite CML). Only cases with score of 4 or 5 by both radiologists were selected for the study. The initial and 2-week follow-up skeletal surveys were reviewed in consensus for presence of the following signs: corner fracture, thin bucket handle fracture, thick bucket handle fracture, bucket handle fracture with endochondral bone filling the gap, subphyseal lucency, deformed corner, and subperiosteal new bone formation. We used the Kruskal-Wallis test to evaluate for significant difference in thickness among thin bucket handle fracture, thick bucket handle fracture, and bucket handle fracture with endochondral bone filling the gap. We included 26 children (12 girls) with age range 1-9.9months who had a combined 34 distal tibia CMLs. Thin bucket handle fracture (n=13, 38.2%) was only seen on initial survey. On follow-up, six children had thick bucket handle fracture and four had bucket handle fracture with endochondral bone filling the gap. Fourteen thick bucket handle fractures (n=9) or bucket handle fractures with endochondral bone filling the gap (n=5) were noted on initial surveys; on follow-up, three (21.4%) had deformed corner, one (7.1%) had corner fracture, one (7.1%) had subphyseal lucency, and five (35.7%) were normal. None demonstrated thin bucket handle fracture on follow-up. Two of the nine (22.2%) thick bucket handle fractures became thicker, and 3/9 (33.3%) became bucket handle fractures with endochondral bone filling the gap. The metaphysis normalized in 8/34 (23.5%) CMLs on follow-up surveys. The thickness of thin bucket handle fracture was less than 1mm (mean±standard deviation [SD] = 0.6±0.2mm), which was significantly thinner (P<0.0001) compared with thick bucket handle fracture (1.7±0.5mm) and bucket handle fracture with endochondral bone filling the gap (1.9±0.6mm). The lack of thin bucket handle fractures on any follow-up skeletal surveys suggests this sign represents an acute phase of injury. The next phases of healing appear to be thick bucket handle fracture followed by bucket handle fracture with endochondral bone filling the gap. It is important to note that normalization of the metaphysis at 2-week follow-up does not exclude CML because this was seen in about one-fifth of cases.

Classic Metaphyseal Lesions and Abuse

Research Article| September 01 2019 Classic Metaphyseal Lesions and Abuse AAP Grand Rounds (2019) 42 (3): 28. https://doi.org/10.1542/gr.42-3-28 Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Cite Icon Cite Search Site Citation Classic Metaphyseal Lesions and Abuse. AAP Grand Rounds September 2019; 42 (3): 28. https://doi.org/10.1542/gr.42-3-28 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search toolbar search search input Search input auto suggest filter your search All PublicationsAll JournalsAAP Grand RoundsPediatricsHospital PediatricsPediatrics In ReviewNeoReviewsAAP NewsAll AAP Sites Search Advanced Search Topics: abuse, physical, fractures, perpetrator of child and adult abuse, torsion, traction, shoulder region, musculoskeletal torsion, function Source: Adamsbaum C, De Boissieu P, Teglas JP, et al. Classic metaphyseal lesions among victims of abuse. J Pediatr. 2019; 209: 154.e2– 159.e2; doi: https://doi.org/10.1016/j.jpeds.2019.02.013Google Scholar Investigators from multiple institutions in France conducted a retrospective review to better understand the circumstances of injuries in physically abused infants with classic metaphyseal lesion (CML), which is a fracture through immature metaphyseal bone near the growth plate. CML is thought to be caused by torsion or traction and is considered to be highly suggestive of abuse.1 Children included in the study were identified through review of cases of suspected abuse referred by the court system in France for expert medical evaluation. Only children with CML were included; all study participants who were living were examined by one of the authors. Data from medical records, abuse evaluation, police investigations, and court records were abstracted for study participants. Logistic regression was used to assess the association between anatomical location of CML and the presence of subdural hematoma (SDH). The mechanism of injury causing CML was described among a subset of study participants in whom the perpetrator admitted abusing the child. A total of 67 children with CML from physical abuse were identified. The mean age of victims was 3.4 months with no sex predominance; 8 children were born prematurely (gestational age <37 weeks). In addition to CML, all children had other signs of abuse. Concurrent injuries included unusual bruising (30 children) and burns (4 children). CML was identified on routine skeletal surveys in 43 patients (64%). Overall, 44 children had multiple CMLs. CML was more common in lower than upper extremities. There were 27 children with CML in whom the perpetrator admitted abusing the child. Among these were 19 male perpetrators (18 fathers and 1 stepfather) and 8 female perpetrators (3 mothers and 5 nannies). These perpetrators admitted using excessive force on joints by means of torsion, traction, violent compression, and other forced movements. Among male perpetrators, violent handling was described during diapering in 44% of cases, and among all perpetrators the use of excessive force during dressing or undressing the infant occurred in 30% of cases. Perpetrators of both sexes cited crying or feeding as trigger events. There were 24 children with SDH. Compared to CML at other anatomic sites, CML of the shoulder was associated with an increased risk of concurrent SDH (OR, 4.85; 95% CI, 1.16–20.18). The authors conclude that CMLs are caused by violent acts inflicted during routine care of infants. Dr Dubik has disclosed no financial relationship relevant to this commentary. This commentary does not contain a discussion of an unapproved/investigative use of a commercial product/device. Caffey first described the radiological pattern of metaphyseal injury in abused infants.2 Although no specific fracture type is pathognomonic for physical abuse,3 CML, also known as “corner” or “bucket handle” fracture, is considered a strong indicator of inflicted injury in infants.4 However, iatrogenic causes of CMLs have been documented, including... You do not currently have access to this content.

Classic metaphyseal lesion of distal tibia following footling breech delivery.

Classic metaphyseal lesions associated with childbirth are rare. We report a distal tibial metaphyseal fracture following a difficult breech delivery. Classic metaphyseal fractures are considered highly specific injuries associated with non-accidental trauma. This case depicts a classic metaphyseal lesion sustained during footling breech extraction in an urgent delivery. The traction and torque placed on the distal extremities during this difficult delivery suggest a potential mechanism for this injury.

Prevalence of metaphyseal injury and its mimickers in otherwise healthy children under two years of age

Metaphyseal lesions in infants and toddlers are believed to have a high specificity for inflicted injury. To examine the prevalence of metaphyseal injury and its mimickers in otherwise healthy children younger than 2years of age. During 2010-2015, all children 2years old and younger seen at the Accident and Emergency (A&E) Department due to an injury who had radiographs taken were included. Information on mechanism and clinical findings were drawn from the medical notes. All radiographs were reviewed by two of five researchers together with an experienced paediatric radiologist, registering fracture site and type, and metaphyseal appearances. Four hundred and eight children (212 boys) (mean age: 17.7months, range: 3-24months) were included, of whom 149 (77 boys) had a total of 162 fractures (incidence of 5.4 per 1,000 children). Only one metaphyseal lesion, without a history of trauma, was seen. Of the 860 metaphyses analysed, 140 (16.3%) were defined as either irregular (74/860, 8.6%) or as having a metaphyseal collar (66/860, 7.7%). Sixty-four of the 66 collars (97.0%) and 54/104 irregularities (60.8%) were located around the wrist and the ankle, while 25/74 irregularities (33.8%) were found around the knee joint. Metaphyseal lesions with a history of trauma did not occur in otherwise healthy neonates and infants younger than 2years of age, indicating that this type of fracture has a particular trauma mechanism. Metaphyseal irregularities/collars are frequently seen and should not be mistaken for a classic metaphyseal lesion.

An important marker explained

The “classic metaphyseal lesion,” a unique corner fracture of long bones, has long been considered a specific marker of child abuse. Although a few paid defendant “experts” have attempted to challenge this concept, it has continued to be accepted by child abuse specialists. A useful series of classic metaphyseal lesions, collected from a group in Paris, has provided helpful new information on these fractures. These investigators studied 67 children with these lesions, accumulated over several years. They focused on children in whom there had been a confession by a perpetrator. The confessions described the types of forces generating the injury, as well as the typical situations in which they occurred (eg, diapering, dressing). Interestingly, classic metaphyseal lesions of the shoulder were associated with subdural hematomas, a plausible but previously unreported association. This study strengthens and adds to our understanding of these important markers of abuse. Article page 154▶ Classic Metaphyseal Lesions among Victims of AbuseThe Journal of PediatricsVol. 209PreviewTo use legal statements by perpetrators to gain new insights into the causative mechanism of classic metaphyseal lesion (CML). The CML, so called “corner fracture,” is considered a highly specific marker for abuse in infants. However, the precise correlation between CMLs and abusive head trauma is still unknown. Full-Text PDF

Classic Metaphyseal Lesions among Victims of Abuse

To use legal statements by perpetrators to gain new insights into the causative mechanism of classic metaphyseal lesion (CML). The CML, so called "corner fracture," is considered a highly specific marker for abuse in infants. However, the precise correlation between CMLs and abusive head trauma is still unknown. In this retrospective observational study, we selected 67 cases with at least 1 CML from a 15-year cohort of legally prosecuted child abuse cases. Their clinical, radiologic, and forensic records were analyzed. In 27 cases, the perpetrator confessed to abusing the child and described the events. Potential associations with subdural hematoma and with confession were evaluated using 2 separate binary logistic regression models. All 67 infants showed other signs of abuse. Median age was 3.4months. Over 65% had multiple CMLs. Knees and ankles were predominantly involved (64%). Only CMLs of the shoulder were significantly associated with subdural hematoma (P=.03). Different-age fractures were more common in the nonsubdural hematoma group (P=.01). In the group with confessions, perpetrators admitted inflicting violent indirect skeletal forces (torsion, traction, compression, and forced movements). The most common circumstance was diapering (44%), reported by male perpetrators only (P=.03) followed by dressing/undressing (30%). The violence was habitual in 67% of cases. This unique forensic case series shows that CMLs are caused by violent acts inflicted most during physical care of infants. The frequency of habitual violence responsible for CMLs deserves greater attention.

Ultrasound findings in classic metaphyseal lesions: emphasis on the metaphyseal bone collar and zone of provisional calcification.

The classic metaphyseal lesion (CML) is highly specific for non-accidental trauma in infants. While the radiographic findings are well documented, there is little literature on the ultrasound (US) appearance. To evaluate US findings in CMLs identified on radiographs. This institutional review board-approved, retrospective evaluation of targeted US of CMLs was performed in selected groups of children from 2014 to 2017. Only CMLs confidently identified on radiography by a consensus of two radiologists were included. US images were obtained with a linear transducer, including longitudinal images at lateral, anterior, medial and posterior aspects. Two pediatric radiologists evaluated the US appearance, specifically the metaphyseal bone collar for thickness, deformity and fracture, as well as the sonographic zone of provisional calcification for irregularity and appearance of multiple lines. Radiography was the reference standard. Twenty-two patients (13 female; mean age: 4.2months) were identified, with 39 CMLs in the tibia (n=22), femur (n=11), humerus (n=3), radius (n=2) and fibula (n=1). Thirty-three of the 39 CMLs (85%) were identified on US, while 6 (15%) were not seen (false negatives). Thirty of the 39 (77%) had metaphyseal bone collar thickening, 29 (74%) had collar deformity and 12 (31%) had visible fracture of the collar. At the sonographic zone of provisional calcification, 16/39 (41%) had irregularity and 5 (13%) had multiple lines visible. Identifying metaphyseal bone collar and zone of provisional calcification abnormalities is key to recognizing CMLs on US. While additional studies are necessary to evaluate the accuracy of US in the diagnosis of CMLs, our findings suggest US may have a potential role in either confirming or evaluating radiographically equivocal/occult CMLs.

Subperiosteal new bone formation with the distal tibial classic metaphyseal lesion: prevalence on radiographic skeletal surveys.

The classic metaphyseal lesion (CML) is a strong indicator of infant abuse, and the distal tibia is one of the most common sites for this injury. To determine the prevalence of subperiosteal new bone formation accompanying the distal tibial CMLs identified on infant skeletal surveys. Skeletal surveys performed for suspected infant abuse (2005-2017) were reviewed. Inclusion criteria were 1) anteroposterior (AP) and lateral radiographs of a distal tibial CML from the initial survey, 2) AP radiograph from the 2-week follow-up survey, 3) additional fractures, 4) child protection team consults and 5) mandated report filing for suspected abuse. We identified 22 distal tibial CMLs from 16 infants. Radiographs of these lesions were shown on the picture archiving and communication system to two blinded pediatric radiologists. Readers indicated the presence/absence of subperiosteal new bone formation on individual and combinations of images. Inter-reader agreements were fair (kappa=0.47). The prevalence of subperiosteal new bone formation on initial AP radiograph was 34%. Significant increases in the prevalence were found with the addition of follow-up AP radiograph (57%; P<0.001), initial lateral radiograph (57%; P=0.002) and follow-up AP plus initial lateral radiographs (71%; P<0.001). Statistically significant increases in prevalence were also noted when the third view was added to the other two views (increase of 14%; P=0.024). Even when skeletal surveys include initial AP, lateral and follow-up AP radiographs of the tibia, nearly one-third of distal tibial CMLs will fail to demonstrate subperiosteal new bone formation.

The added value of a second read by pediatric radiologists for outside skeletal surveys.

Fractures are the second most common finding in non-accidental trauma after cutaneous signs. Interpreting skeletal surveys could be challenging as some fractures are subtle and due to anatomical variations that can mimic injuries. To determine the effect of a second read by a pediatric radiologist of skeletal surveys for suspected non-accidental trauma initially read at referring hospitals by general radiologists. In 2016 and 2017, we identified all patients referred to our children's hospital with previous surveys performed and read at a community hospital by an outside radiologist. We excluded patients older than 3years and studies performed at a children's hospital. The surveys were reviewed by a pediatric radiologist with the printed outside report available. Surveys with disagreement between outside read and pediatric radiologist read were reviewed by a second pediatric radiologist. A disagreement in the second read included only definite discrepant findings agreed upon by both pediatric radiologists. The Fisher exact test was performed to compare the ratio of discrepancies between readers in normal and abnormal surveys. Two hundred twenty-five surveys were performed (120 male) at 62 referring hospitals, with a mean patient age of 10.5months (range: 5days-3years). The outside read identified fractures in 104/225 (46.2%) surveys. Thirty-seven of the 225 (16.4%) contained discrepancies in interpretation (n=111). Most of these disagreements (29/37, 78.4%) resulted in a significant change in the report. There was a significant (P<0.0001) difference between disagreement rate in outside read negative (4/111, 3.2%) and positive surveys (34/104, 31.7%). The second read identified additional fractures in 22/225 (9.8%) of the surveys and disagreed with first-read fractures in 17/256 (7.6%). Four of 19 (21.1%) classic metaphyseal lesions diagnosed by the outside read were normal variants; 18 classic metaphyseal lesions were missed by the outside read. This study supports second reads by pediatric radiologists of skeletal surveys for non-accidental trauma.

The distal tibial classic metaphyseal lesion: medial versus lateral cortical injury.

The distal tibia is a common location for the classic metaphyseal lesion (CML). Prior radiologic-pathologic studies have suggested a tendency for medial, as opposed to lateral, cortical injury with the CML, but there has been no formal study of the geographic distribution of this strong indicator of abuse. This study compares medial versus lateral cortical involvement of distal tibial CMLs in a clinical cohort of infants with suspected abuse. Reports of 1,020 skeletal surveys performed for suspected abuse (July 2005-June 2016) were reviewed. Twenty-six distal tibial CMLs (14 unilateral, 6 bilateral) with anteroposterior (AP) and lateral projections on the initial skeletal survey and at least an AP view on the follow-up survey were identified in 20 infants. Two blinded pediatric radiologists determined if the medial and/or lateral margins of the distal tibial metaphysis were involved by the CML. Average interreader absolute agreement and kappa scores were 0.69-0.90 and 0.45-0.72, respectively. Average intrareader absolute agreement and kappa scores were 0.65-0.88 and 0.44-0.57, respectively. Analyses showed that the distal tibial CML almost always involved the medial cortical margin (reader 1=89%, reader 2=88%, pooled=89%) and the fracture infrequently involved the lateral cortical margin (reader 1=12%, reader 2=38%, pooled=26%). The percentage point difference between fracture involvement in medial and lateral margins was statistically significant from zero (P<0.001). The distal tibial CML is most often encountered medially; lateral involvement is uncommon. This observation should help guide the radiologic diagnosis and could have implications for understanding the biomechanics of this distinctive injury.

Biomechanics of the classic metaphyseal lesion: finite element analysis.

The classic metaphyseal lesion (CML) is strongly associated with infant abuse, but the biomechanics responsible for this injury have not been rigorously studied. Radiologic and CT-pathological correlates show that the distal tibial CML always involves the cortex near the subperiosteal bone collar, with variable extension of the fracture into the medullary cavity. Therefore, it is reasonable to assume that the primary site of bone failure is cortical, rather than intramedullary. This study focuses on the strain patterns generated from finite element modeling to identify loading scenarios and regions of the cortex that are susceptible to bone failure. A geometric model was constructed from a normal 3-month-old infant's distal tibia and fibula. The model's boundary conditions were set to mimic forceful manipulation of the ankle with eight load modalities (tension, compression, internal rotation, external rotation, dorsiflexion, plantar flexion, valgus bending and varus bending). For all modalities except internal and external rotation, simulations showed increased cortical strains near the subperiosteal bone collar. Tension generated the largest magnitude of cortical strain (24%) that was uniformly distributed near the subperiosteal bone collar. Compression generated the same distribution of strain but to a lesser magnitude overall (15%). Dorsiflexion and plantar flexion generated high (22%) and moderate (14%) localized cortical strains, respectively, near the subperiosteal bone collar. Lower cortical strains resulted from valgus bending, varus bending, internal rotation and external rotation (8-10%). The highest valgus and varus bending cortical strains occurred medially. These simulations suggest that the likelihood of the initial cortical bone failure of the CML is higher along the margin of the subperiosteal bone collar when the ankle is under tension, compression, valgus bending, varus bending, dorsiflexion and plantar flexion, but not under internal and external rotation. Focal cortical strains along the medial margins of the subperiosteal bone collar with varus and valgus bending may explain the known tendency for focal distal tibial CMLs to occur medially. Further research is needed to determine the threshold of applied forces required to produce this strong indicator of infant abuse.

Multiple fractures in infants who have Ehlers-Danlos/hypermobility syndrome and or vitamin D deficiency: A case series of 72 infants whose parents were accused of child abuse and neglect.

ABSTRACTObjective: To increase the level of awareness that Ehlers-Danlos/hypermobility syndrome (EDS) and vitamin D deficiency are associated with infantile fragility fractures and radiologic features that may be mistakenly reported to be caused by non-accidental trauma due to Child Abuse and Neglect (CAN).Patients and Methods: We constructed a case series, the largest to date, of infants with EDS who were vitamin D sufficient, insufficient and deficient and infants without EDS but with documented vitamin D deficiency and radiologic evidence of rickets who presented with multiple fractures originally diagnosed as being non-accidental and caused by child abuse. These infants were referred to the outpatient Bone Health Care Clinic at Boston University Medical Campus over a 6-year (2010–2015) period. We also present 6 index cases in which the court concluded that there was no convincing evidence of child abuse and the infants were returned to their parents. Institutional Review Board (IRB) approval was obtained.Results: We present 72 cases of infants with multiple fractures diagnosed to be caused by non-accidental trauma. All infants were younger than one year of age. Among them, 93%(67) had clinical evidence of EDS and/or a family history with a confirmed clinical diagnosis of at least one parent having EDS and the other 7%(5) without evidence of EDS had vitamin D deficiency/infantile rickets. Three of the EDS infants were diagnosed as osteogenesis imperfecta (OI)/EDS overlap syndrome. The most common fractures noted at diagnosis were ribs and extremity fractures (including classic metaphyseal lesions). Serum levels of 25-hydroxyvitamin D [25(OH)D] were reported in 48 infants (18.0 ± 8.5 ng/ml) and in 30 mothers (21.3 ± 11.7 ng/ml). Sixty-three percent (27) of the EDS infants who had their serum 25(OH)D measured were vitamin D deficient 25(OH)D<20 ng/ml and 5 were vitamin D sufficient 25(OH)D>30 ng/ml. The mean serum level for infants with vitamin D deficiency/rickets was (10.2 ± 3.0 ng/ml)Conclusion: EDS, OI/EDS and vitamin D deficiency/infantile rickets are associated with fragility fractures in infants that can be misinterpreted as caused by non-accidental trauma due to child abuse.