Imaging the complications of osteochondromas

Malignant transformation of osteochondroma to chondrosarcoma: a challenging case

A 50-year-old female presented with a large palpable mass in the right buttock and proximal thigh, accompanied by sciatic paresthesia. She reported intermittent thigh and knee pain for 5 years, worsening over the previous 6 months. Plain radiography images revealed a pedunculated osteochondroma on the posterolateral aspect of the femur with extensive soft tissue involvement and soft tissue calcifications. A computed tomography (CT) scan showed an osteochondroma with a large adjacent bursa containing multiple foci of calcifications with a "snowstorm" appearance. A diagnostic dilemma arose regarding whether the condition represented reactive bursitis secondary to osteochondroma or a malignant transformation to chondrosarcoma with intra-bursal invasion. Magnetic resonance imaging (MRI) indicated a thick cartilage cap of osteochondroma measuring 53 mm and multiple cartilage nodules in the bursa along with heterogeneous enhancement in cartilage islands. Moreover, evidence of adjacent muscle invasion and sciatic nerve encasement was noted. These findings suggested an unusual diagnosis of malignant transformation of the osteochondroma to chondrosarcoma with intra-bursal invasion. The patient underwent wide-margin resection of the proximal femur and tumoral soft tissue, reconstructed with a proximal femoral mega prosthesis. Histologic evaluation confirmed a well-differentiated chondrosarcoma with intra-bursal invasion. This case highlights the critical role of diagnostic imaging in differentiating between benign and malignant complications associated with osteochondroma.

Can the Cartilaginous Thickness Determine the Risk of Malignancy in Pelvic Cartilaginous Tumors, and How Accurate is the Preoperative Biopsy of These Tumors?

BACKGROUND

Peripheral osteochondral tumors are common, and the management of tumors presenting in the pelvis is challenging and a controversial topic. Some have suggested that cartilage cap thickness may indicate malignant potential, but this supposition is not well validated.

QUESTIONS/PURPOSES

(1) How accurate is preoperative biopsy in determining whether a peripheral cartilage tumor of the pelvis is benign or malignant? (2) Is the thickness of the cartilage cap as determined by MRI associated with the likelihood that a given peripheral cartilage tumor is malignant? (3) What is local recurrence-free survival (LRFS), metastasis-free survival (MFS), and disease-specific survival (DSS) in peripheral chondrosarcoma of the pelvis and is it associated with surgical margin?

METHODS

Between 2005 and 2022, 289 patients had diagnoses of peripheral cartilage tumors of the pelvis (either pedunculated or sessile) and were treated at one tertiary sarcoma center (the Royal Orthopaedic Hospital, Birmingham, UK). These patients were identified retrospectively from a longitudinally maintained institutional database. Those whose tumors were asymptomatic and discovered incidentally and had cartilage caps ≤ 1.5 cm were discharged (95 patients), leaving 194 patients with tumors that were either symptomatic or had cartilage caps > 1.5 cm. Tumors that were asymptomatic and had a cartilage cap > 1.5 cm were followed with MRIs for 2 years and discharged without biopsy if the tumors did not grow or change in appearance (15 patients). Patients with symptomatic tumors that had cartilage caps ≤ 1.5 cm underwent removal without biopsy (63 patients). A total of 82 patients (63 with caps ≤ 1.5 cm and 19 with caps > 1.5 cm, whose treatment deviated from the routine at the time) had their tumors removed without biopsy. This left 97 patients who underwent biopsy before removal of peripheral cartilage tumors of the pelvis, and this was the group we used to answer research question 1. The thickness of the cartilage cap was recorded from MRI and measuring to the nearest millimeter, with measurements taken perpendicular in the plane that best allowed the greatest measurement. Patient survival rates were assessed using the Kaplan-Meier method with 95% confidence intervals as median observation times to estimate MFS, LRFS, and DSS.

RESULTS

Of malignant tumors biopsied, in 49% (40 of 82), the biopsy result was recorded as benign (or was considered uncertain regarding malignancy). A malignant diagnosis was correctly reported in biopsy reports in 51% (42 of 82) of patients, and if biopsy samples with uncertainty regarding malignancy were excluded, the biopsy identified a lesion as being malignant in 84% (42 of 50) of patients. The biopsy results correlated with the final histologic grade as recorded from the resected specimen in only 33% (27 of 82) of patients. Among these 82 patients, 15 biopsies underestimated the final histologic grade. The median cartilage cap thickness for all benign osteochondromas was 0.5 cm (range 0.1 to 4.0 cm), and the median cartilage cap thickness for malignant peripheral chondrosarcomas was 8.0 cm (range 3.0 to 19 cm, difference of medians 7.5 cm; p < 0.01). LRFS was 49% (95% CI 35% to 63%) at 3 years for patients with malignant peripheral tumors with < 1-mm margins, and LRFS was 97% (95% CI 92% to 100%) for patients with malignant peripheral tumors with ≥ 1-mm margins (p < 0.01). DSS was 100% at 3 years for Grade 1 chondrosarcomas, 94% (95% CI 86% to 100%) at 3 years for Grade 2 chondrosarcomas, 73% (95% CI 47% to 99%) at 3 and 5 years for Grade 3 chondrosarcomas, and 20% (95% CI 0% to 55%) at 3 and 5 years for dedifferentiated chondrosarcomas (p < 0.01). DSS was 87% (95% CI 78% to 96%) at 3 years for patients with malignant peripheral tumors with < 1-mm margin, and DSS was 100% at 3 years for patients with malignant peripheral tumors with ≥ 1-mm margins (p = 0.01).

CONCLUSION

A thin cartilage cap (< 3 cm) is characteristic of benign osteochondroma. The likelihood of a cartilage tumor being malignant increases after the cartilage cap thickness exceeds 3 cm. In our experience, preoperative biopsy results were not reliably associated with the final histologic grade or malignancy, being accurate in only 33% of patients. We therefore recommend observation for 2 years for patients with pelvic osteochondromas in which the cap thickness is < 1.5 cm and there is no associated pain. For patients with tumors in which the cap thickness is 1.5 to 3 cm, we recommend either close observation for 2 years or resection, depending on the treating physician's decision. We recommend excision in patients whose pelvic osteochondromas show an increase in thickness or pain, preferably before the cartilage cap thickness is 3 cm. We propose that surgical resection of peripheral cartilage tumors in which the cartilage cap exceeds 3 cm (aiming for clear margins) is reasonable without preoperative biopsy; the role of preoperative biopsy is less helpful because radiologic measurement of the cartilage cap thickness appears to be accurately associated with malignancy. Biopsy might be helpful in patients in whom there is diagnostic uncertainty or when confirming the necessity of extensive surgical procedures. Future studies should evaluate other preoperative tumor qualities in differentiating malignant peripheral cartilage tumors from benign tumors.

LEVEL OF EVIDENCE

Level III, diagnostic study.

Popliteal artery pseudoaneurysm and secondary ipsilateral deep vein thrombosis caused by an exostosis in a mature adult

Exostosis (also known as osteochondroma) is the most common benign bony lump of young people, usually arising at the distal femur. Vascular complications associated with exostoses are rare and include true aneurysm or pseudoaneurysm formation, deep vein thrombosis, arteriovenous fistula, and arterial insufficiency of the limbs. Few case reports describe pseudoaneurysms resulting from exostoses in mature adults, and no consensus has been reached regarding the optimal therapy. We report the case of a 51-year-old male patient complaining of persistent right thigh pain with a pulsatile mass and right calf swelling, without a history of trauma or hereditary multiple exostoses. The diagnosis was confirmed by computed tomography angiography, which showed a pseudoaneurysm of the popliteal artery resulting from an exostosis on the lateral aspect of the distal femur. A Doppler ultrasound examination confirmed popliteal vein thrombosis caused by the compression of the pseudoaneurysm. Surgical treatment consisted of removing the exostosis, excision of the pseudoaneurysm, and an end-to-end anastomosis. The deep vein thrombosis was treated with rivaroxaban for 3 months. The patient was discharged after 6 days and followed up for 6 months with satisfactory results.

Osteochondroma of Distal Femur Managed With Complete Excision: A Case Report

Osteochondromas are benign bone tumors that usually occur between the ages of 10 and 30, with no marked gender preference. These lesions result from the separation of the epiphyseal growth plate and are categorized as growth plate development abnormalities rather than true neoplasms. It is important to note that long-term solitary osteochondromas can evolve into osteosarcomas, with chondrosarcoma being the most common among them. However, the risk of recurrence is considerably reduced if the tumor is completely resected from its original site, with no residual perichondrium or cartilage cap left in place. In this context, a 29-year-old man with osteochondroma in the distal femur was successfully treated with complete resection, showing a favorable evolution.

A Solitary, Large Calcaneal Osteochondroma Growing Extensively After Skeletal Maturity: A Case Report and Review of the Literature

Although osteochondromas are the most common benign tumors in the skeleton, calcaneal osteochondromas are very rare. New onset of pain or rapid growth of the tumor, especially after the closure of the epiphyseal growth plate, might reflect malignant transformation. However, enlargement of solitary osteochondromas reported as benign in a skeletally mature patient is present in the literature. We report the clinical and radiologic findings of a calcaneal osteochondroma with an extremely rare placement and painful rapid growth causing limited ambulation in a 27-year-old male. After surgical removal of the tumor, histologic examination demonstrated no evidence of malignancy, and there was no recurrence during the three-year follow-up.

Classification of Chondrosarcoma: From Characteristic to Challenging Imaging Findings

Chondrosarcomas can be classified into various forms according to the presence or absence of a precursor lesion, location, and histological subtype. The new 2020 World Health Organization (WHO) Classification of Tumors of Soft Tissue and Bone classifies chondrogenic bone tumors as benign, intermediate (locally aggressive), or malignant, and separates atypical cartilaginous tumors (ACTs) and chondrosarcoma grade 1 (CS1) as intermediate and malignant tumors. respectively. Furthermore, the classification categorizes chondrosarcomas (including ACT) into eight subtypes: central conventional (grade 1 vs. 2–3), secondary peripheral (grade 1 vs. 2–3), periosteal, dedifferentiated, mesenchymal, and clear cell chondrosarcoma. Most chondrosarcomas are the low-grade, primary central conventional type. The rarer subtypes include clear cell, mesenchymal, and dedifferentiated chondrosarcomas. Comprehensive analysis of the characteristic imaging findings can help differentiate various forms of chondrosarcomas. However, distinguishing low-grade chondrosarcomas from enchondromas or high-grade chondrosarcomas is radiologically and histopathologically challenging, even for experienced radiologists and pathologists.

An update on the imaging of diaphyseal aclasis

Solitary osteochondromas are common, benign hyaline cartilage-capped exostoses that primarily arise from the metaphyses of long and flat bones. Diaphyseal aclasis is an autosomal dominant condition resulting from EXT1 or EXT2 gene mutations and is characterized by multifocal osteochondromas. These can result in a wide spectrum of complications, such as skeletal deformity, neurological and vascular complications, adventitial bursa formation, fracture, and rarely malignant transformation to peripheral chondrosarcoma. In this review, we outline in detail the multimodality imaging features of DA and its associated complications.

Osteochondroma Presenting Clinically with Carpal Tunnel Syndrome in a 12-Year-old Boy

Introduction

An exostosis is a benign growth of bone, which when capped with cartilage is called osteochondroma, which can appear as solitary or multiple, mostly affecting the long bones, pelvis, and shoulder region. The prevalence of known solitary exostosis is 1-2% in the general population. They are slow growing lesions with rare malignant transformation. In patients with a solitary exostosis, the chance of developing a chondrosarcoma out of an exostosis is around 1%.

Case Report

A 12-year-old boy presented to our outpatient department with complaints of pain, and swelling at the right wrist since 1 year and tingling numbness on and around palmar aspect of index and middle finger since 6 months. The swelling was of size 3 cm × 2 cm, Tinel's sign was positive. His blood parameters were normal. X-ray showed exostoses. Magnetic resonance imaging was suggestive of osteochondroma. Nerve conduction study was normal. Excision biopsy confirmed the diagnosis and also relieved all symptoms.

Conclusion

Our case report is unique in its own way as it reminds us that when presented with a case of osteochondroma of the distal radius in children, carpal tunnel syndrome can also occur.

Osteochondromas: An Updated Review of Epidemiology, Pathogenesis, Clinical Presentation, Radiological Features and Treatment Options

Osteochondroma, the most common benign bone tumor, is a projection on the external surface of the bone, which can be sessile or pedunculated. 85% of osteochondromas present as solitary lesions, while 15% occur in the context of hereditary multiple exostoses (HME), a genetic disorder that is inherited in an autosomal dominant manner. Although often asymptomatic, symptoms may eventuate from compression of adjacent vessels or nerves, fractures, osseous deformities, bursa formation, or malignant transformation. Cartilage cap thickness >2 cm in adults or >3 cm in children as well as new onset of pain or growth, or rapid growth of the lesion, especially after the closure of the growth plate, might reflect cancerous transformation. Surgical resection is indicated for symptomatic lesions, complications, cosmetic reasons or malignant transformation. Excision of the tumor with free margin is the treatment of choice. Local recurrence is less than 2% if complete resection is achieved.

Osteochondroma of the temporal styloid process: a common disease in a rare but vulnerable location

Osteochondromas, the most common benign bone tumor, are typically asymptomatic and discovered incidentally by imaging. Most frequently, osteochondromas occur at the metaphyses of long bones, and rarely involve the head and neck. We report the first case of a symptomatic osteochondroma of the temporal styloid process causing facial nerve paralysis.

Sarcomatous Transformation of Recurrent Scapular Osteochondroma in a Patient with the Hereditary Multiple Osteochondromas: A Case Report and Literature Review

Hereditary multiple osteochondromas (HMO) is an autosomal dominant disease diagnosed by the presence of two or more than two osteochondromas on radiographs. The majority of cases are asymptomatic. The presence of bony growth, pain, and compression of the surrounding structure are the usual presentations. Malignant transformation into chondrosarcoma is the most feared complication. A rapid increase in size, recurrence after the surgical excision, and infiltrating mass may suggest the conversion into chondrosarcoma. Radiological imaging helps in diagnosing malignant transformation. MRI is the investigation of choice to exclude cancer. We hereby present a case of multiple osteochondromas with suspected malignant transformation due to rapidly increasing painful osseous swelling.

Can 18F-FDG PET/CT diagnose malignant change in benign chondroid tumors?

AIM

The aim of this study was to determine whether fluorine-18 fluorodeoxyglucose (F-FDG) PET/computed tomography (CT) can diagnose malignant change in benign chondroid tumors.

PATIENTS AND METHODS

This study included patients with clinicoradiological features of a chondroid tumor who were referred for a F-FDG PET/CT study to evaluate clinical suspicion of malignant change. Metabolic characteristics of the suspected lesion in the form of maximum standardized uptake value (SUVmax) was obtained and compared with histopathology. In patients who were treated conservatively and for whom histopathology was not available, stability of the lesion on clinical/radiological follow-up was used as reference standard. Receiver operating characteristic curve analysis was performed to obtain a SUVmax cutoff value to differentiate between benign and malignant lesions.

RESULTS

Clinical and imaging data of 66 patients was available for analysis. Malignancy was confirmed by histopathology in 40/66 (60.6%) patients with grade 2 chondrosarcomatous change seen in majority. In 26 patients, the final diagnosis was benign tumor (osteochondroma, n=19; enchondroma, n=7). Median SUVmax of malignant lesions was significantly higher compared with the benign lesions (4.0 vs. 2.1, P=0.00). A SUVmax cutoff of 3.1 could differentiate a benign lesion from those with malignant transformation with a sensitivity of 90.3% and specificity of 87% (area under the curve=0.92). Dedifferentiated sarcomas showed a significantly higher uptake than rest of the sarcoma types.

CONCLUSION

F-FDG PET/CT can detect malignant change in benign chondroid neoplasms by showing higher metabolic activity in the area of sarcomatous transformation. It can also identify focus of dedifferentiation which has prognostic and therapeutic implications.

[Acute lower limb ischemia secondary to femoral osteochondroma]

Osteochondromas or bone exostoses are bone tumors commonly found in adolescents or young adults. These benign tumors are usually incidentally discovered, exceptionally by a vascular or nervous complication. We report the case of a 22-year-old patient presenting with left femoral exostosis revealed by an acute ischemia of the lower limb. Clinical examination of the contralateral limb was without abnormality. Computed tomography angiography revealed a thrombosed aneurysm of the supra articular popliteal artery associated to an exostosis of the lower extremity of the femur. Surgical treatment was recommended in this patient: resection of the popliteal aneurysm associated with a end-to-end suture of the popliteal artery and resection of bone exostosis.

Primary Tumor and Tumor-Like Lesions of Bones of the Foot: Single-Center Experience of 166 Cases

Primary bone tumors of the foot are rare lesions. The purpose of the present study was to evaluate the clinical manifestations, treatment modalities, and recurrences of various primary bone tumors of the foot from a specialized center for orthopedic oncology. Among 3681 musculoskeletal tumor cases, which were diagnosed and surgically treated in our hospital from 1983 to 2013, 166 primary tumor and tumor-like bone lesions of the foot (4.5%) were retrospectively reviewed regarding age, gender, localization, biopsy-revealed diagnosis, applied treatment modalities, follow-up period, and recurrence, if any. Of the 166 primary bone tumors of the foot, 155 (93.4%) were benign and 11 (6.6%) were malignant. The most common primary benign bone tumor was a unicameral bone cyst (57 of 155; 36.8%), and the most common malignant tumor was chondrosarcoma (7 of 11; 63.6%). The hindfoot was the most common location for both primary benign (104 of 155; 67.1%) and malignant (6 of 11; 54.5%) bone tumors of the foot. The results of our study have confirmed that the radiologic findings can be confusing owing to the structural and histopathologic features of the bones of the foot; thus, histopathologic diagnosis should be considered for foot involvement. Because the characteristics of the compartments in the foot allow for the rapid spread of malignant lesions, aggressive surgical management and wider resection are recommended to prevent recurrence and further spread.

Solitary Osteochondroma of the Ventral Scapula Associated with Large Bursa Formation and Pseudowinging of the Scapula: A Case Report and Literature Review

Osteochondroma (OC) is the most common benign bone tumor and may occur on any bone in which endochondral ossification develops. Although scapular OC accounts for less than 5% of the cases of solitary OC, OC is the most common lesion among the tumors and tumor-like lesions of the scapula. OC that develops near the medial scapular border easily causes friction with the ribcage; hence, almost half the number of cases of OC associated with marked bursa formation develops in the ventral scapula. We report a case of a 27-year-old female with a painful OC of the ventral scapular surface associated with large bursa formation and pseudowinging of the scapula. After l2 years of follow-up with magnetic resonance imaging, we confirm that the accompanied bursa left at surgery disappears.

Osteochondroma and Spinal Cord Compression in a Patient With Hereditary Multiple Exostoses: A Case Report

OBJECTIVE

The purpose of this report was to describe the presentation of a patient with hereditary multiple exostoses and thoracic spinal cord compression from an osteochondroma.

CLINICAL FEATURES

A 31-year-old female presented to a chiropractic clinic with a history of hereditary multiple exostoses and back pain that had existed since the age of 16 years. She had a past medical history that was remarkable for 3 prior surgeries for mass removal. Examination revealed a left upper midscapular mass with decreased sensation.

INTERVENTION/OUTCOME

Magnetic resonance imaging, computed tomography, and biopsy led to a diagnosis of osteochondroma. These diagnostic modalities confirmed that there was no malignant degeneration. Initial magnetic resonance imaging revealed a large expansive lesion involving the left posterior elements at the region of T3-T4. Subsequent thoracic hemilaminectomy and resection of the spinal tumor with posterior instrumentation and stabilization from T2-T5 resulted in 90% overall subjective improvement.

CONCLUSIONS

A detailed case history, thorough examination, guided advanced imaging, and biopsy provide important information for the diagnosis and appropriate treatment of expansive lesions in patients with hereditary multiple exostoses.

[Popliteal artery pseudoaneurysm caused by femur exostosis: A pediatric case]

Exostoses, or osteochondromas are benign bone tumors that have developed on the bone surface. These benign tumors can be asymptomatic or lead to complications, for instance arterial pseudoaneurysm. We report a case of a pseudoaneurysm of the popliteal artery treated surgically in a 17-year-old girl with a solitary exostosis of the right femur. Surgery was closure of the pseudoaneurysm and a bypass using a venous graft.

Imaging of benign complications of exostoses of the shoulder, pelvic girdles and appendicular skeleton

Exostoses are the most common benign bone tumors, accounting for 10 to 15% of all bone tumors. They develop at the bone surface by enchondral ossification and stop growing when skeletal maturity has been reached. At first, exostoses are covered by a smooth cartilage cap that progressively ossifies with skeleton maturity. Then they may regress, partly or even completely. Osteochondromas may be solitary or multiple, with the latter associated with hereditary multiple exostoses (HME). Exostoses develop during childhood and become symptomatic during the third decade of life in the case of solitary exostoses, or earlier, in case of HME. They stop growing after puberty, when the epiphyseal plates close. Most exostoses remain asymptomatic. Local complications, usually benign, may occur, such as fractures or mechanical impingements upon nearby structures. In rare cases, sarcomatous degeneration occurs. Most of these complications have been described in case reports. This article describes the imaging features of benign complications of exostoses of the shoulder, pelvic girdles and appendicular.

Non-Traumatic Fracture of an Osteochondroma Mimicking Malignant Degeneration in an Adult with Hereditary Multiple Exostoses

A 38-year-old man with a known history of hereditary multiple exostoses and no history of trauma presented with a painful right femur mass. While the clinical presentation was concerning for malignant degeneration or a large overlying bursitis, the radiologic evaluation demonstrated a large fractured pedunculated osteochondroma with a thick cartilage cap and underlying bone marrow edema. Traumatic fracture of an osteochondroma is an uncommon complication in patients with hereditary multiple exostoses. This case highlights an unusual presentation in which a patient with hereditary multiple exostoses and no history of trauma presented with a large fractured osteochondroma.

[Osteochondroma of the femur revealed by an iterative lesion of the vastus lateralis: report of a case]

Nous rapportons le cas d'un jeune homme de 32 ans présentant un ostéochondrome de fémur droit révélé par une lésion itérative du vaste externe. Le patient consulte pour des épisodes récidivants de douleur de la cuisse droite avec impotence fonctionnelle, survenant lors d'une activité sportive et imposant son arrêt. L’échographie a montré une déchirure du vaste latéral, avec un hématome témoignant d'une lésion récente et présence de fragments osseux à proximité évoquant un arrachement osseux. Un bilan radiologique standard a montré une exostose pédiculaire à la partie supérieure de la diaphyse fémorale compliquée d'une fracture. La tomodensitométrie était en faveur d'une exostose fémorale antérieure dont les limites étaient régulières et bien corticalisées. La résection chirurgicale de la tumeur et l'examen anatomo-pathologique ont permis de confirmer le diagnostic d'un ostéochondrome.

Osteochondroma in long-term survivors of high-risk neuroblastoma

BACKGROUND

Osteochondromas are benign bony protrusions that can be spontaneous or associated with radiotherapy (RT). Current treatment of high-risk neuroblastoma includes dose-intensive chemotherapy, local RT, an anti-GD2 monoclonal antibody (MoAb), and isotretinoin. Late effects are emerging.

METHODS

The authors examined osteochondromas in 362 patients who were aged <10 years when diagnosed with neuroblastoma, had received a MoAb plus isotretinoin since 2000, and had survived >24 months from the time of the first dose of the MoAb. The incidence rate of osteochondroma was determined using the competing risks approach, in which the primary event was osteochondroma calculated from the date of neuroblastoma diagnosis and the competing event was death without osteochondroma.

RESULTS

A total of 21 osteochondroma cases were found among 14 patients who were aged 5.7 to 15.3 years (median, 10.4 years) and 3.1 to 11.2 years (median, 8.2 years) from the time of neuroblastoma diagnosis. The cumulative incidence rate was 0.6% at 5 years and 4.9% at 10 years from the neuroblastoma diagnosis. Nine osteochondromas were revealed incidentally during assessments of neuroblastoma disease status or bone age. Thirteen osteochondromas were detected outside RT portals and had characteristics of spontaneous forms. Complications were limited to pain necessitating surgical resection in 3 patients, but follow-up was short at 0.3 to 7.7 years (median, 3.5 years).

CONCLUSIONS

Osteochondromas in long-term survivors of neuroblastoma should be expected because these benign growths can be related to RT and these patients undergo radiologic studies over years, are monitored for late toxicities through and beyond adolescence, and receive special attention (because of concerns about disease recurrence) if they develop a bony protuberance. A pathogenic role for chemotherapy, anti-GD2 MoAbs, or isotretinoin remains speculative.

Exostoses and vascular complications in the lower limbs: two case reports and review of the literature

Exostosis is a very common bone tumor. Complications occur in 4% of the cases (nerve compression, exostosis degeneration, orthopedic complication); however, vascular complications are rare. This is the report of 2 cases of vascular complications that occurred in 2 patients-one with a solitary form and the other with hereditary multiple exostoses. A review of the literature found 57 cases of lower limb vascular complication, secondary to an exostosis. The most common vascular complication was the popliteal aneurysm. Femoral exostosis topography was found in 89% of the cases. A triggering trauma was found in 36% of the cases and the most common form was the solitary exostosis (58%). The treatment of these complications is surgical, and it treats the vascular lesion and the bone tumor at the same time. Surgical treatment of exostosis vascular complications is recommended as an urgent procedure to prevent the occurrence of irreversible damages.

A case report of osteochondroma with unusual clinical and imaging presentation

Osteochondroma or exostosis is a bony developmental anomaly, which arises from exophytic outgrowth on bone surfaces in a characteristic manner. Osteochondroma is asymptomatic and grows away from the nearby joint. This paper reports an unusual presentation of osteochondroma in which the patient was surprisingly completely symptomatic. The lesion grew toward the nearby joint and the radiographic findings were not compatible with surgical findings.

Chondroma of the diaphragm mimicking a giant liver tumor with calcification: report of a case

Extraskeletal chondroma is an unusual benign tumor, which rarely arises in the diaphragm. We report a case of chondroma of the diaphragm in a 31-year-old woman. Initially, a benign liver tumor with calcification was suspected, based on pre and intraoperative examination findings. Although parts of the tumor were contiguous with the diaphragm, its connections with the diaphragm were much narrower than its connection with the liver, which suggested a liver tumor. Pathological examination subsequently revealed that the chondroma was contiguous with the diaphragm and that there was a distinct border between the tumor and the liver; thus, the tumor was diagnosed as a chondroma of the diaphragm.

Osteochondroma: ignore or investigate?

Osteochondromas are bone protuberances surrounded by a cartilage layer. They generally affect the extremities of the long bones in an immature skeleton and deform them. They usually occur singly, but a multiple form of presentation may be found. They have a very characteristic appearance and are easily diagnosed. However, an atypical site (in the axial skeleton) and/or malignant transformation of the lesion may sometimes make it difficult to identify osteochondromas immediately by means of radiographic examination. In these cases, imaging examinations that are more refined are necessary. Although osteochondromas do not directly affect these patients’ life expectancy, certain complications may occur, with varying degrees of severity.

Bursal synovial chondromatosis formation following osteochondroma resection

Osteochondroma is a common tumor of the bone and can be complicated by adventitial bursa formation and malignant transformation of the cartilaginous cap. Synovial chondromatosis formation within these bursae is extremely rare and can be confused with malignant transformation of the osteochondroma cap to a chondrosarcoma. We describe a case of extra-articular synovial chondromatosis formation several years following osteochondroma resection. Cartilage nodule formation within the bursal synovial lining and proliferation of cartilage debris shed from the cartilaginous cap during surgery or biopsy are potential etiologies of this rare complication of osteochondromas.

Clinical characteristics of hereditary multiple exostoses: a retrospective study of mainland chinese cases in recent 23 years

Hereditary multiple exostoses (HME) are an autosomal dominant skeletal disease with wide variations in clinical manifestations among different ethnic groups. This study investigated the epidemiology, clinical presentations, pathogenetic features and treatment strategies of HME in mainland China. We searched and reviewed the related cases published since 1990 by searching electronic databases, namely SinoMed database, Wanfang database, CNKI, Web of Science and PubMed as well as Google search engines. A total of 1051 cases of HME (male-to-female ratio 1.5:1) were investigated and the diagnosis was made in 83% before the age of 10 years. Approximately 96% patients had a family history. Long bones, ribs, scapula and pelvis were the frequently affected sites. Most patients were asymptomatic with multiple palpable masses. Common complications included angular deformities, impingement on neighbouring tissues and impaired articular function. Chondrosarcomas transformation occurred in 2% Chinese cases. Among the cases examined, about 18% had mutations in EXT1 and 28% in EXT2. Frameshift, nonsense and missense mutations represented the majority of HME-causing mutations. Diagnosis of HME was made based on the clinical presentations and radiological documentations. Most patients needed no treatment. Surgical treatment was often directed to remove symptomatic exostoses, particularly those of suspected malignancy degeneration, and correction of skeletal deformities. This study shows some variance from current literature regarding other ethnic populations and may provide valuable baseline assessment of the natural history of HME in mainland China.

Non-Traumatic Fracture Of Pedunculated Osteochondroma - A case report and brief review of literature

Introduction:

Non-traumatic fracture of pedunculated osteochondroma is a known, but rare complication. Treatment protocols for such complication are debatable, however, surgical intervene have been advocated.

Case Report:

14 years old male presented with pain and redness around the knee with no history of injury. Radiograph showed fracture of solitary osteochondroma of femur. Excision was done through posterolateral approach and confirmed with histopathology. Patient returned to activities at 2 weeks post surgery

Conclusion:

Atraumatic fractures may occur due to strong muscular contractions in cases of pedunculated osteochondroma. Surgical excision gives prompt relief from symtoms

The imaging of cartilaginous bone tumours. II. Chondrosarcoma

Chondrosarcoma is the third most common primary malignant bone tumour. There are various histological subtypes of chondrosarcomas, of which conventional intramedullary chondrosarcoma is by far the most common. Rarer sub-types include clear cell chondrosarcoma, myxoid chondrosarcoma, mesenchymal chondrosarcoma and dedifferentiated chondrosarcoma. Chondrosarcoma is also classified into central, peripheral and periosteal, dependent upon the lesion site, and into primary chondrosarcoma if the lesion arises de novo and secondary chondrosarcoma if the tumour arises in a pre-existing lesion. The various subtypes of chondrosarcoma have characteristic imaging features that may aid diagnosis and may guide biopsy, therefore potentially preventing misdiagnosis. The aim of this article is to provide an overview of the pertinent clinical and imaging findings of the different forms of chondrosarcoma.

The imaging of cartilaginous bone tumours. I. Benign lesions

Benign cartilage tumours of bone are the most common benign primary bone tumours and include osteochondroma, (en)chondroma, periosteal chondroma, chondroblastoma and chondromyxoid fibroma. These neoplasms often demonstrate typical imaging features, which in conjunction with lesion location and clinical history, often allow an accurate diagnosis. The aim of this article is to review the clinical and imaging features of benign cartilage neoplasms of bone, as well as the complications of these lesions.

An analysis of indications for surgical excision and complications in 116 consecutive cases of osteochondroma

The indications for surgery in 116 cases of osteochondroma included cosmetic problem in 38, pain (on hitting some object or continuous pain due to bursitis) in 50, pressure (on adjacent nerves) in 18, hindrances of joint movements in 8, fracture of the growth in 1 and malignant change in 1 patient. The complications of surgical excision included infection in 2 patients (which was controlled with antibiotics and dressings) and injury to posterior tibial artery in one case (which was repaired with the help of vascular surgeon immediately). In 94 patients, the tumour was excised before epiphyseal fusion (done carefully so as to prevent damage to the growth plate). It is not essential to wait until skeletal maturity as many patients want to get it excised as early as possible for cosmetic reasons. All the cases were relieved of their symptoms. There was no recurrence.

Pathology of the thoracic wall: congenital and acquired

This review aims to cover the main congenital and acquired lesions that arise in the thoracic wall of infants and children. Imaging often plays an essential role in the evaluation of symptomatic and asymptomatic thoracic wall abnormalities. The use of appropriate imaging modalities for each condition will be addressed, as well as the range of benign and malignant conditions that can occur.

Integrated PET/CT in evaluating sarcomatous transformation in osteochondromas

AIM

To study the role of PET-CT in evaluating sarcomatous transformation in osteochondromas.

MATERIALS AND METHODS

This was a retrospective analysis of a prospective data base of 12 patients from 2005 to 2007 with a clinical diagnosis of an osteocartilaginous lesion who were referred for a FDG PET-CT study to evaluate for possible malignant transformation. Imaging was performed on a GE Discovery ST PET-CT system after intravenous injection of 370 MBq (10 mCi) of F-18 FDG.

RESULTS

Seven patients with histopathological evidence of a sarcomatous transformation to grade II chondrosarcoma showed moderate to high FDG uptake (SUV 3.3-6.9), whereas 1 patient with a dedifferentiated chondrosarcoma showed a focus of very intense uptake (SUV 11.4). Four patients with histopathological and/or clinical or follow-up diagnosis of a benign osteocartilaginous lesion showed low grade FDG uptake (SUV 0.8-1.3). FDG uptake was also noted in an asymptomatic osteochondroma which on histopathology revealed a grade II chondrosarcoma.

CONCLUSIONS

Whole body FDG PET-CT is an important adjunct to conventional morphologic imaging in evaluating suspected malignant transformation in osteochondromas. Increased glucose metabolism can help diagnose sarcomatous transformation at the suspected sites as well as detect early malignant change at clinically unsuspected sites. Moreover, its ability to detect a focus of dedifferentiation can be useful for prognostication and to plan adjuvant treatment. A small cohort limits statistically sound conclusions to be drawn from this study, however further prospective trials based on these findings can help explore the potential application of FDG PET-CT in this clinical condition.

An unusual complication of pubic exostosis

We report the case of a left superior pubic ramus osteochondroma occurring in a 29-year-old man. The patient consulted for a multiple exostoses disease revealed by a painful induration at the base of his penis. This induration was increasing in volume and causing discomfort during sexual intercourse and when sitting for a prolonged period of time. CT-scan examination showed a pedunculated osteochondroma of the left superior pubic ramus compressing the urethra. Surgical resection of the tumor confirmed the diagnosis of osteochondroma. At a 2-year follow-up delay, all symptoms had regressed with no evidence of recurrence.

Giant solitary osteochondroma of the inferior medial calcaneal tubercle: a case report and review of the literature

Small osteophytes are frequently encountered in the foot and ankle, and are not to be confused with true osteochondromas, which are relatively uncommon in this region. They most often affect long bones of the appendicular skeleton but may involve flat bones as well. Osteochondromas are benign osseous neoplasms with a distinct hyaline cartilage cap originating from the physis and cease growing with skeletal maturity. Osteochondroma are often treated conservatively unless they become symptomatic, painful, demonstrate rapid or new growth, enlarge after skeletal maturity, and/or exhibit signs of malignant transformation. In this report, we present a case of a giant (8 cm x 4.2 cm x 2.1 cm) osteochondroma in an adult occurring on the inferior medial tubercle of the calcaneus that underwent excision, with 3.5 years of follow-up without recurrence. To our knowledge this is the largest osteochondroma affecting the inferior medial tubercle of the calcaneus. This case demonstrates that large osteochondromas may occur in the foot, and also confirms that benign osteochondroma growth may occur in adulthood. A detailed review of osteochondroma occurrence in the foot is presented along with a review of the diagnostic work-up to evaluate for malignant transformation.

LEVEL OF CLINICAL EVIDENCE

4.

Sciatic nerve compression due to femoral neck osteochondroma: MDCT and MR findings

A 34-year-old man presented with a 15-month history of pain along the left sciatic nerve. Radiographs and computed tomography (CT) revealed an exostosis on the postero-inferior aspect of the left femoral neck. Ultrasonographic examination of left upper thigh and a pelvic magnetic resonance (MR) imaging showed an enlarged sciatic nerve adjacent to the exostosis. Although peroneal and ulnar neuropathies due to the compression by exostosis are reported frequently, imaging findings of sciatic nerve involvement were not well documented in the literature. Multidetector CT and MR findings of a sciatic nerve compression caused by a femoral neck exostosis were presented.

Sarcomatous transformation in diaphyseal aclasis

Multiple hereditary exostosis (or diaphyseal aclasis) is a condition characterized by the development of multiple osteochondromas. The tendency for malignant transformation into chondrosarcoma is well known. Malignancy typically arises from the cartilaginous cap of the osteochondroma. Radiographs supplemented by computed tomography have an important role in the diagnosis of this condition. Magnetic resonance imaging shows the features of sarcomatous change and aids in differentiating malignancy from pseudotumours.

Intra-osseous pseudoaneurysm following curettage of an aneurysmal bone cyst

BACKGROUND

Pseudoaneurysms secondary to bone tumours are rare and most of the reported cases are related to osteochondromas, either due to direct pressure or following surgery. Aneurysmal bone cysts are relatively common bony lesions usually treated by curettage.

DISCUSSION

We describe an unusual case of pseudoaneurysm of the anterior tibial artery complicating curettage of an aneurysmal bone cyst which presented as a rapidly enlarging mass clinically thought to be rapid recurrence of the tumour. This was successfully treated by embolisation.

Complicação vascular de osteocondroma: relato de caso

Osteocondromas ou exostoses são os tumores benignos mais comuns do tecido ósseo. Eles surgem durante o período de crescimento e, raramente, são responsáveis por complicações vasculares. No presente relato, reportamos um caso de paciente com osteocondroma no membro inferior e complicação vascular provocada pela compressão da artéria poplítea. O paciente apresentava queixas de dor em membro inferior direito quando foi investigado com angiografia e radiografia, que identificaram a lesão vascular e a tumoração óssea. Os tratamentos cirúrgicos simultâneos de ambas as lesões foram realizados com boa evolução pós-operatória.