Recurrent CTNNB1 mutations in craniofacial osteomas.

Osteoma is a benign bone forming tumor predominantly arising on the surface of craniofacial bones. While the vast majority of osteomas develops sporadically, a small subset of cases is associated with Gardner syndrome, a phenotypic variant of familial adenomatous polyposis caused by mutations in the APC gene resulting in aberrant activation of WNT/ß-catenin signaling. In a sequencing analysis on a cohort of sporadic, non-syndromal osteomas, we identified hotspot mutations in the CTNNB1 gene (encoding ß-catenin) in 22 of 36 cases (61.1%), harbouring allelic frequencies ranging from 0.04 to 0.53, with the known S45P variant representing the most frequent alteration. Based on NanoString multiplex expression profiling performed in a subset of cases, CTNNB1-mutated osteomas segregated in a defined "WNT-cluster", substantiating functionality of CTNNB1 mutations which are associated with ß-catenin stabilization. Our findings for the first time convincingly show that osteomas represent genetically-driven neoplasms and provide evidence that aberrant WNT/ß-catenin signaling plays a fundamental role in their pathogenesis, in line with the well-known function of WNT/ß-catenin in osteogenesis. Our study contributes to a better understanding of the molecular pathogenesis underlying osteoma development and establishes a helpful diagnostic molecular marker for morphologically challenging cases.

Pain in survivors of Ewing sarcoma: Prevalence, associated factors and prediction of recurrence.

BACKGROUND: While the prognosis of patients with Ewing sarcoma (EwS) is improving, little is known about the frequency of pain and its risk factors in survivors of EwS. This study aims to analyse the prevalence and risk factors of pain and its predictive value for recurrence. PATIENTS AND METHODS: In patients with remission after treatment of EwS, frequency and characteristics of pain within the first 5 years of follow up were assessed retrospectively. RESULTS: Of 80 patients, 37 (46%) presented with at least one episode of pain. Chronic pain (>3 months) was observed in 10 patients (13%). Experience of at least one episode of pain was associated with prior combined local treatment (surgery and radiation compared to surgery alone; odds ratio [OR] 5.83, 95% confidence interval [CI] 1.43-34.9, P = .007). A total of 59 episodes of pain were observed, including 47 acute and 12 chronic episodes. Lower limb pain accounted for 46% (27/59) of all episodes of pain, and was associated with primary tumour of the pelvis or lower extremity (OR 4.29, 95% CI 1.18-18.21, P = .025), which represented 64% (51/80) of all EwS. The positive predictive value of pain for recurrence was only 12%. CONCLUSION: Pain is a common problem in survivors of EwS, which mostly affects the lower extremity, and should be regularly assessed. Interventions to reduce pain may be particularly important in patients with combined local treatment with surgery and radiation, who seem to be at considerably increased risk for pain. Patients presenting with pain should be examined for recurrence.

Activating mutations in the MAP-kinase pathway define non-ossifying fibroma of bone.

Non-ossifying fibroma (NOF), which occasionally results in pathologic fracture, is considered the most common benign and self-limiting lesion of the growing skeleton. By DNA sequencing we have identified hotspot KRAS, FGFR1 and NF1 mutations in 48 of 59 patients (81.4%) with NOF, at allele frequencies ranging from 0.04 to 0.61. Our findings define NOF as a genetically driven neoplasm caused in most cases by activated MAP-kinase signalling. Interestingly, this driving force either diminishes over time or at least is not sufficient to prevent autonomous regression and resolution. Beyond its contribution to a better understanding of the molecular pathogenesis of NOF, this study adds another benign lesion to the spectrum of KRAS- and MAP-kinase signalling-driven tumours. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Anatomic shape variants of extremitas sternalis claviculae as collected from sternoclavicular thin-slice CT-studies of 2820 male borderline-adults.

Within medical age assessment practice, the indicator "medial clavicular ossification" constitutes crucial evidence capable of excluding age minority "beyond reasonable doubt" concerning age-disputed individuals doubtfully claiming children's rights during legal procedures. Yet, one of its characteristics affects the morphological variability including a fair amount of downright peculiar appearances. As a result, inexperienced examiners are tempted to classify actually not-assessable formations according to the two established developmental typologies of Schmeling et al. and Kellinghaus et al. being at the same time the most frequent systemic error of age-related clavicular taxation. Since a respective overview appears missing, the study extracts not-assessable shape variants of the medial collar bone from a large sample of 2820 male borderline-adults as seen from thin-slice, sternoclavicular computed tomography. The two already highlighted configurations "more than one, medial, secondary ossification centres" and "medial metaphyseal concavity" are found as the most commonly encountered features impeding reliable delineation of staging criteria. In accordance with previous literature, it is emphasized that "qualified" rating of extremitas sternalis claviculae within age assessment practice presupposes "knowledge about the diversity of [its] anatomic shape variants."

[The importance of radiology in bone sarcoma diagnostics : Initial and advanced diagnostics]. / Stellenwert der Radiologie in der Diagnostik der Knochensarkome : Initiale und weiterführende Diagnostik.

BACKGROUND: Reliable diagnostic assessment of malignant bone lesions remains a challenge in all the medical disciplines involved. The high incidence of benign (mainly pediatric) bone lesions needs to be distinguished from the rare malignant counterparts. If clinical presentation and patient history are unable to exclude a malignant tumour, adequate imaging of the affected region is necessary. OBJECTIVES: This article focuses on giving implementable advice in dealing with problems and questions arising in the diagnostic process of treating patients with suspected or confirmed bone sarcoma. Also, follow-up recommendations from a radiological point of view are presented. METHODS: Review and discussion of relevant literature against personal experiences in the medical imaging of patients with bone sarcomas. RESULTS: Interpretation of projection radiographic images usually succeeds in assessing a bone tumour's dignity by evaluating periosteal reaction, the formation of a tumour matrix and consideration of the Lodwick classification. A current adaptation of the classic Lodwick classification incorporates diagnostic possibilities of more recent imaging techniques (magnetic resonance imaging (MRI), positron emission tomography (PET)) and is presented in this article. Plain radiographs are superseded by MRI as the primary imaging performed when depicting bone lesions with increasing frequency. The role of MRI in terms of primary diagnostics, staging, planning of biopsy tracts and tumour resections, evaluation of treatment response and follow-up are discussed. All diagnostic imaging techniques, including whole-body imaging methods, relevant in the diagnosis and therapy of bone sarcomas are presented in the sequence in which they appear during treatment. CONCLUSIONS: Radiological imaging and expertise are important pillars in diagnosis and treatment of bone sarcomas. A variety of complementing imaging techniques provide a treatment-relevant basis significant for all medical disciplines involved.

Forensic age assessment by 3.0T MRI of the knee: proposal of a new MRI classification of ossification stages.

PURPOSE: To explore the possibility of determining majority via a morphology-based examination of the epiphyseal-diaphyseal fusion by 3.0 T magnetic resonance imaging (MRI), a prospective cross-sectional study developing and applying a new stage classification was conducted. MATERIALS AND METHODS: 344 male and 350 female volunteers of German nationality between the ages of 12-24 years were scanned between May 2013 and June 2015. A 3.0 T MRI scanner was used, acquiring a T1-weighted (T1-w) turbo spin-echo sequence (TSE) and a T2-weighted (T2-w) TSE sequence with fat suppression by spectral pre-saturation with inversion recovery (SPIR). The gathered information was sifted and a five-stage classification was formulated as a hypothesis. The images were then assessed using this classification. The relevant statistics were defined, the intra- and interobserver agreements were determined, and the differences between the sexes were analysed. RESULTS: The application of the new classification made it possible to correctly assess majority in both sexes by the examination of the epiphyses of the knee joint. The intra- and interobserver agreement levels were very good (κ > 0.80). The Mann-Whitney-U Test implied significant sex-related differences for most stages. CONCLUSION: Applying the presented MRI classification, it is possible to determine the completion of the 18th year of life in either sex by 3.0 T MRI of the knee joint. KEY POINTS: • Based on prospective referential data a new MRI classification was formulated. • The setting allows assessment of the age of an individual's skeletal development. • The classification scheme allows the reliable determination of majority in both sexes. • The staging shows a high reproducibility for instructed and trained professional personnel. • The proposed classification is likely to be adaptable to other long bone epiphyses.

Intraindividual incongruences of medially ossifying clavicles in borderline adults as seen from thin-slice CT studies of 2595 male persons.

In the past, numerous studies have documented the possibility of intraindividual differing appearances of the paired age-marker "medial clavicular ossification" in borderline adults. However, the extent of the divergences is rarely mentioned. Against that the article describes this phenomenon from a large sample of 2595 male persons by means of thin-slice CT imaging of the sternoclavicular regions. For determining the ossification stage of the medial clavicles, the two accepted classifications by Schmeling et al. (five main stages) and Kellinghaus et al. (six substages) were applied and buildings deviating from that labelled as atypical "norm variants". The longstanding observation could be confirmed that intraindividual stage discrepancies of this age indicator are generally moderate and do not exceed one main stage or two substages of the respective classifications. It is concluded that stage determination should be scrutinized, if a dissimilarity seems to show larger differences.

Impact of the Interdisciplinary Tumor Board of the Cooperative Ewing Sarcoma Study Group on local therapy and overall survival of Ewing sarcoma patients after induction therapy.

BACKGROUND: The Interdisciplinary Tumor Board (ITB) of the Cooperative Ewing Sarcoma Study (CESS) Group was investigated to assess its impact on the overall survival (OAS) of Ewing sarcoma (EwS) patients. The ITB functions as a reference center for the international institutions participating in the clinical trials of the CESS group, but is also available internationally to patients who have not been treated within an appropriate clinical trial. The value of tumor boards in terms of benefit for the patients and the health care system in general is not well documented and is also the subject of controversial discussions. A review of the representative literature is included. METHODS: Data were analyzed from 481 patients who had been registered into the European Ewing Tumor Working Initiative of National Groups (EURO E.W.I.N.G.-99) clinical trial via the CESS data center between 2006 and 2009; this included 331 patients with localized disease and another 150 individuals with metastases at diagnosis. Median follow-up time was 3.2 years. RESULTS: Improved OAS was observed for patients with metastases who had received recommendations from the ITB compared with those who had not received recommendations. In patients with localized disease, a recommendation from the ITB had no influence on OAS. CONCLUSION: As a reference center for a rare disease, recommendations from our ITB impacted local therapy and led to higher OAS in patients with metastatic disease. To our knowledge, this is the first analysis that examines the value of a reference tumor board on a rare disease.

Recurrence of Ewing sarcoma: Is detection by imaging follow-up protocol associated with survival advantage?

BACKGROUND: The Cooperative Ewing Sarcoma Study and the Late Effects Surveillance System of the Society for Paediatric Oncology and Haematology recommend a structured follow-up imaging protocol (FUIP) for patients with Ewing sarcoma (EwS) with decreasing frequency of imaging over the first 5 years. The present study aims to assess the effectiveness of the FUIP for EwS patients regarding survival after relapse. PATIENTS AND METHODS: A retrospective multicenter analysis on 160 eligible patients with EwS recurrence was performed. Potential survival differences following recurrence diagnosis between patients with protocol-detected and symptomatic relapse were investigated using the Kaplan-Meier method. Additional subgroup analyses were performed on the relapse type. Overall survival (OS) was calculated from diagnosis of relapse to last follow-up or death. RESULTS: In the multicenter analysis, recurrence was detected by FUIP in 77 of 160 patients (48%) and due to symptoms in 83 patients (52%). Regarding the entire study population, OS was significantly superior in patients with protocol-detected relapse compared to patients with symptomatic relapse (median, 2.4 vs. 1.2 years; P < 0.001). In the subgroup analyses, patients whose lung recurrences were detected by the FUIP experienced longer survival after recurrence than those whose recurrences were detected symptomatically (P = 0.023). In the 83 symptomatic patients, pain was the most prevalent symptom of relapse (72%). CONCLUSION: FUIP may benefit survival in EwS relapse, especially in lung recurrence. Pain was the leading symptom of relapse.

Impact of helmet use in equestrian-related traumatic brain injury: a matched-pairs analysis.

PURPOSE: Traumatic brain injury is an important health concern in equestrian sports. Nevertheless, the use of safety helmets, especially in recreational riding, is reported to be rare. The purpose of this study was to perform the first matched-pairs analysis of traumatic brain injury with regard to the use of helmets. MATERIALS AND METHODS: In a multicenter retrospective database analysis 40 patients (mean age: 35 ± 17.13 years; 34 female & 6 male) were combined in 20 matched pairs based on age group, gender and trauma mechanism. Admission trauma computed tomography was qualitatively analyzed for the presence or absence of fractures or intracranial hemorrhage. Quantitatively, in patients with intracranial hemorrhage dedicated volumetry of the blood volume was performed. Odds ratio and relative risk were calculated for the endpoints fractures and intracranial hemorrhage. Crude risk ratio and lesion volume differences between helmeted and unhelmeted riders were compared. RESULTS: Concerning skull fractures, in this cohort 6 patients (85.7% of all patients with fractures) did not wear a helmet and only one (14.3%) wore a helmet (p = .068).and fractures were considered more complex in the unhelmeted subgroup. Intracranial hemorrhage occurred significantly more often in the unhelmeted subgroup (10 vs. 2; p = .008). Moreover, the total lesion volume with 19.31 ± 23.93ml in the unhelmeted subgroup, presenting with intracranial hemorrhage, was significantly higher than in the control group (0.65 ± 0.35ml; p = .002). Odds ratios were 9 for intracranial hemorrhage (p = .014) and 8.14 for skull fractures without helmet (p = .09). Altogether, the relative risk for intracranial bleeding for unhelmeted riders was 5-fold higher and the relative risk reduction was 96% by wearing a safety helmet. CONCLUSIONS: Under consideration of comparable trauma mechanisms, horseback riders that do not wear a safety helmet are at risk to suffer significantly more severe brain injury than helmeted riders. Therefore, safety helmets are recommendable for all horseback riders.

Forensic age estimation by magnetic resonance imaging of the knee: the definite relevance in bony fusion of the distal femoral- and the proximal tibial epiphyses using closest-to-bone T1 TSE sequence.

OBJECTIVES: To clarify the relevance of the bony fusion of the distal femoral and the proximal tibial epiphyses by means of magnetic resonance imaging (MRI), a prospective cross-sectional cohort study was performed with a special focus on a reliable determination of the 14th, 16th and 18th years of life. METHODS: We scanned 658 German volunteers in the age bracket 12-24 years using a 3.0 T MR-scanner and utilising a T1 turbo spin-echo sequence representing true bone anatomy. Minimum, maximum, mean ± standard deviation and median with lower and upper quartiles were defined. Intra- and interobserver agreements were determined (Cohen's kappa). The statistical relevance of sex-related differences was analysed (Mann-Whitney U test, p < 0.05, exact, two-sided). RESULTS: The bony fusion took place before the 18th year of life in both epiphyses. The Mann-Whitney U test results imply significant sex-related differences for most stages. For both epiphyses, the intra observer (κ femur 0.961; tibia 0.971) and interobserver (κ femur 0.941; tibia 0.951) agreement levels were very good. CONCLUSION: The 14th and the 16th years of life can be determined in both sexes, but the completion of the 18th year of life cannot solely be determined by the bony fusion, as depicted by closest-to-bone MRI. KEY POINTS: • Forensic age estimation by means of MRI of the knee is feasible. • MRI provides data about the ossification process without using ionising radiation. • The method allows the determination of the 14th and 16th years of life. • The bony fusion is not suitable as the sole indicator of majority. • The chosen classification is easy to use for specially trained professional personnel.

Comparison of imaging planes during CT-based evaluation of clavicular ossification: a multi-center study.

Determining the ossification stage of the medial clavicular epiphysis by computed tomography represents the currently recommended methodology for the question of whether a living individual has completed the 18th or 21st year of life. In the present study, thin-slice CT scans of 1078 sternoclavicular joints were reconstructed in axial and coronal image series and evaluated according to the two classification systems established for age diagnostics using the clavicle. Both image series (axial and coronal) were analyzed separately. When comparing the results of axial and coronal view, a different ossification stage was found in 35.6% of the clavicles. The results suggest an influence of the imaging plane on the process of stage determination. In order to further approximate the three-dimensional and asymmetrical structure of the epiphyseal ossification center, the usage of at least two different reformation types may be recommended. In practice, only those reference studies should be applied which exactly employed the same number and orientations of the reformation types that are going to be used in the respective routine case.

Forensic age diagnostics using projection radiography of the clavicle: a prospective multi-center validation study.

The radiological investigation of the ossification stage of the medial clavicular epiphysis represents the crucial tool for assessing whether a living individual has completed the age of 18 years. However, exposure to radiation cannot always be accepted due to legal reasons and radiation-free methods still lack reference data or are not available. Therefore, this study examines the role of pre-existing radiographic material of the clavicles, making it necessary to prospectively validate the established five-stage classification system for evaluating the clavicular ossification process as well as to enlarge the so far very limited pool of available reference data. Accordingly, standard posterior-anterior projection radiographs of 836 sternoclavicular joints prospectively obtained during 418 forensic autopsies (age range 15-30 years) were analyzed. Stage III was first found at ages 16 and 15 (males/females), stage IV at ages 22 and 21 (males/females), and stage V at age 26 in both sexes. The presented results principally corroborate the previous reference data from 2004, suggesting reliability of the five-stage classification system. In conclusion, chest radiographs may still be useful for forensic age diagnostics in living individuals but only in certain cases. In age estimations which can be planned in advance, projection radiography of the clavicle must still be considered obsolete.

[Forensic age estimation in juveniles and young adults: Reducing the range of scatter in age diagnosis by combining different methods]. / Forensische Altersschätzung bei Jugendlichen und jungen Erwachsenen: Streubreitenreduktion der Altersdiagnose durch Kombination der Methoden.

The dramatic rise in the number of refugees entering Germany means that age estimation for juveniles and young adults whose age is unclear but relevant to legal and official procedures has become more important than ever. Until now, whether and to what extent the combination of methods recommended by the Study Group on Forensic Age Diagnostics has resulted in a reduction of the range of scatter of the summarized age diagnosis has been unclear. Hand skeletal age, third molar mineralization stage and ossification stage of the medial clavicular epiphyses were determined for 307 individuals aged between 10 and 29 at time of death on whom autopsies were performed at the Institutes of Legal Medicine in Berlin, Frankfurt am Main and Hamburg between 2001 and 2011. To measure the range of scatter, linear regression analysis was used to calculate the standard error of estimate for each of the above methods individually and in combination. It was found that combining the above methods led to a reduction in the range of scatter. Due to various limitations of the study, the statistical parameters determined cannot, however, be used for age estimation practice.

Dental age estimation in living individuals using 3.0 T MRI of lower third molars.

In order to increase the validity of age estimation in adolescents and young adults when there is no legitimation for X-ray examinations, it seems desirable to be able to assess the mineralization of third molars using X-ray-free imaging procedures. In the present study, the mineralization stages of lower third molars were determined prospectively in 269 male and 248 female individuals aged 12 to 24 years using 3.0 T MRI. The classification system of Demirjian et al. was used to determine the stages. This study presents the minima and maxima, means and standard deviations, median values, and lower and upper quartiles separately for both sexes, for the mineralization stages B-H. Statistically significant sex differences were observed for the mineralization stages C, E, F, and G, and a faster developmental rate was observed for males. It was concluded that magnetic resonance imaging is an X-ray-free alternative to orthopantomography when assessing mineralization of third molars.

Projection radiography of the clavicle: still recommendable for forensic age diagnostics in living individuals?

As superimposition effects often impede the evaluation of the ossification status of the medial clavicular epiphysis in standard posterior-anterior (PA) radiographs, additional oblique images (right anterior oblique, RAO, and left anterior oblique, LAO) are currently recommended to allow for reliable stage assessments. The present study examines the influence of the radiographic projection type on stage determination. To this end, 836 sternoclavicular joints were prospectively obtained during forensic autopsies of bodies aged between 15 and 30 years. Subsequently, three different radiographs (PA, RAO, and LAO) were taken from each specimen and separately evaluated as to the developmental stage of the medial clavicular epiphysis. A forensically established five-stage classification system was used. In 25 % of the cases, the medial clavicular epiphysis depicted in an oblique projection showed a different ossification stage than in the PA projection. In at least 10 % of the cases, a higher ossification stage was observed which would have significant disadvantages in criminal proceedings (ethically unacceptable error). In conclusion, the usage of the current radiographic reference data, which rely upon chest radiographs taken as PA projections, appears to be inadmissible for oblique projections. Projection radiography of the clavicle can therefore no longer be recommended for forensic age estimation practice. As to the question of whether an individual has achieved the age of 18 or 21, computed tomography of the clavicle must be regarded as the exclusive method of choice.

In vivo monitoring of angiogenesis during tendon repair: a novel MRI-based technique in a rat patellar tendon model.

PURPOSE: Recent in vivo studies were able to show the impairing effect of neoangiogenesis in degenerative tendon diseases. Clinical in vivo monitoring of angiogenesis in injured tendons therefore seems to be crucial for an accurate therapeutic approach. The aim of this study was to develop a novel magnetic resonance imaging (MRI)-based technique for observing angiogenesis during tendon healing in vivo. METHODS: Tendinopathy was induced by an in situ freezing model of rat patellar tendon and monitored after 7, 14, and 28 days. Animals were randomly divided into an imaging and immunohistochemical group. MRI with a 'blood pool' contrast agent was used to determine neoangiogenesis during tendon healing. MRI was compared to histochemical staining and quantification of blood vessels in injured and native tendons. RESULTS: MRI data revealed a peak in changes in the transverse relaxation rate (ΔR 2*), which is proportional to relative blood volume, 7 days after surgery and decrease until day 28. Histological microvessel density and vascular endothelial growth factor synthesis were also most evident at day 7 and decreased over time. CONCLUSIONS: The current results are demonstrating a time-dependent correlation between microvessel density and ΔR 2*. Thus, MRI-based evaluation of angiogenesis in the tendon might be a new promising technique for in vivo monitoring of angiogenesis and therapy response in the future.

Forensic age estimation in living individuals using 3.0 T MRI of the distal femur.

To increase the reliability of forensic age estimations in living adolescents and young adults where there is no legitimation for X-ray examinations, it would be desirable to establish radiation-free imaging methods. In the present study, the ossification stage of the distal femoral epiphysis was determined retrospectively in 166 male and 124 female individuals in the age group 10 to 30 years using 3.0T MRI. When evaluating the ossification stage, a combination of the classifications proposed by Schmeling et al. and by Kellinghaus et al. was used. Within the study population, stages 3b, 3c and 4 did not occur in the male sex before the 14th birthday, although the validity of the results is distinctly limited relative to stage 3b in view of the small number of cases. In females, stages 3c and 4 did not occur before the 14th birthday. Stage 4 did not occur in males before the 18th birthday. Should this result be confirmed in future studies, there would be an additional criterion providing evidence that the age of 18 years has been completed.

Influence of the examiner's qualification and sources of error during stage determination of the medial clavicular epiphysis by means of computed tomography.

Computed tomography (CT) of the medial clavicular epiphysis has been well established in forensic age estimations of living individuals undergoing criminal proceedings. The present study examines the influence of the examiner's qualification on the determination of the clavicular ossification stage. Additionally, the most frequent sources of error made during the stage assessment process should be uncovered. To this end, thin-slice CT scans of 1,420 clavicles were evaluated by one inexperienced and two experienced examiners. The latter did the evaluations in consensus. Two classification systems, a five-stage system and a substaging system for the main stages 2 and 3, were used. Prior to three of his six assessment sessions, the inexperienced examiner was specifically taught staging of clavicles. Comparison of the examiners' results revealed increasing inter- and intraobserver agreements with increasing state of qualification of the inexperienced examiner (from κ= 0.494 to 0.674 and from κ= 0.634 to 0.783, respectively). The attribution of a not-assessable anatomic shape variant to an ossification stage was identified as the most frequent error during stage determination (n= 349), followed by the overlooking of the epiphyseal scar defining stage 4 (n= 144). As to the clavicular substages, classifying substage 3a instead of 3b was found to be the most frequent error (n= 69). The data of this study indicate that κ values must not be considered as objective measures for inter- and intraobserver agreements. Furthermore, a high degree of specific qualification, particularly the knowledge about the diversity of anatomic shape variants, appears to be mandatory and indispensable for reliable evaluation of the medial clavicular epiphysis.

Congenital osteofibrous dysplasia Campanacci: spontaneous postbioptic regression.

Osteofibrous dysplasia Campanacci is a rare benign bone tumor most frequently observed in young childhood. The exclusive localization in the tibia is very characteristic. The incidence of congenital primary bone tumors is an absolute rarity. We report a case of a newborn with a histologically proven osteofibrous dysplasia Campanacci at the tibia presenting a regular radiographic follow-up. After a small open biopsy and spontaneous minor fracture, the lesion rapidly remodeled within 1½ months and almost completely regressed with restutio ad integrum. Surgical intervention in this tumor entity at childhood age has been shown to have a high recurrence rate but due to lack of experience with newborns, guidelines do not exist. We analyze the radiologic and histologic differential diagnosis of juvenile adamantinoma and emphasize that congenital peripheral bone tumors should be treated conservatively when malignancy is excluded.