Giant solitary synovial chondromatosis

Giant synovial chondromatosis of hip

Synovial chondromatosis is a rare, benign condition occurring due to metaplasia of synovium. A 65-year-old woman presented with pain in her right hip for 6 years. On examination, a swelling was palpable at the base of scarpa's triangle and her right hip movements were restricted. Imaging modalities showed ossified nodules in the antero-inferior aspect of the hip joint, joint effusion and arthritic changes. We diagnosed the patient to have synovial chondromatosis with secondary arthritis of the hip joint. We performed a total hip arthroplasty with simultaneous synovectomy and extraction of the osteochondral loose bodies, 5 of which were about 2×2 cm in size. We found that excessive acetabular reaming was required due to craters, the osteochondral masses formed on the acetabular surface. Histopathological analysis confirmed the diagnosis. The patient had an excellent functional outcome and no recurrence 5 years following the surgery.

Early Diagnosis of Giant Solitary Synovial Chondromatosis of the Hip Using Ultrasound-guided Synovial Biopsy: A Case Report

The diagnosis of synovial chondromatosis (SCM) is usually delayed, as the arthroscopic-guided synovial biopsy is postponed owing to its invasive nature. We report the timely diagnosis of a giant solitary synovial chondromatosis of the hip in a 32-year-old woman using ultrasound-guided synovial biopsy. This technique revealed to be safe and successful in the diagnosis of SCM, when the imaging studies were obscure. Moreover, it avoided the potential arthroscopy-associated complications. We recommend ultrasound-guided synovium biopsy as a less invasive and less complicated technique for the early diagnosis of SCM in future workouts.

Imaging features of synovial chondromatosis of the temporomandibular joint: a report of 34 cases

AIM

To investigate the imaging features of synovial chondromatosis of the temporomandibular joint (TMJ), which is a rare benign arthropathy with cartilaginous proliferation.

MATERIALS AND METHODS

Computed tomography and magnetic resonance imaging examinations of 34 patients with histopathologically confirmed primary synovial chondromatosis of the TMJ were reviewed retrospectively. Imaging features including the lesion epicentre, destruction/sclerosis of surrounding bone, calcification, periosteal reaction, osteophyte, lesion size, and joint space dimensions were assessed.

RESULTS

Thirty-one of thirty-four patients (91.2%) showed the superior joint space as the lesion epicentre. For the mandibular condyle, more than one-third of patients (14/34; 41.2%) showed no destruction, and more than half of patients (19/34; 55.9%) showed no sclerosis. Conversely, >70% of patients showed destruction and sclerosis of the articular eminence/glenoid fossa, while >80% of patients (28/34; 82.4%) presented with various calcifications, including the ring-and-arc (9/34; 26.5%) and popcorn (13/34; 38.2%) types. The mean joint space on the affected side was significantly larger than that of the unaffected side (p<0.001). More than three-fourths of patients (76.9%) experienced no interval increase in lesion size during an average of 1.6 years of follow-up.

CONCLUSION

Synovial chondromatosis of the TMJ demonstrated several imaging features, including the lesion centre being located in the superior joint space, resultant articular eminence/glenoid fossa-oriented bone changes, ring-and-arc and popcorn calcification, joint space widening, and self-limiting growth. These imaging features may be helpful in differentiating synovial chondromatosis from other lesions of the TMJ.

Extraskeletal Para-articular Osteochondroma of the Ankle Joint in a Child: A Case Report

CASE

We present a rare case of extraskeletal para-articular osteochondroma (ESPAOC) in the ankle of a 9-year-old boy, which was causing pain and limiting the range of motion of the ankle joint. The lesion might have also contributed to the deformity of the medial aspect of the talus. Total resection resolved all of the symptoms, with no recurrence at 1-year postoperatively.

CONCLUSION

Operative excision should be considered when ESPAOC directly restricts ankle motion because it can lead to chronic pain and joint degeneration if left untreated.

Soft tissue tumours of the elbow: current concepts

Soft tissue tumours of the elbow are mostly benign. Malignant tumours in this area, although uncommon, often present unique clinical and histopathological characteristics that are helpful for diagnosis.Management of soft tissue tumours around the elbow may be challenging because of their rarity and the proximity to neurovascular structures. Careful staging, histological diagnosis and treatment are essential to optimize clinical outcome. A missed or delayed diagnosis or an improperly executed biopsy may have devastating consequences for the patient.This article reviews the most common benign and malignant soft tissue tumours of the elbow and discusses the clinicopathological findings, imaging features and current therapeutic concepts. Cite this article: EFORT Open Rev 2019;4:668-677. DOI: 10.1302/2058-5241.4.190002.

Synovial chondromatosis of the hip, a case report and literature review

A case of giant synovial chondromatosis of the hip with extra-articular localisation in the ileopectineal bursa is presented and the literature concerning this condition is reviewed. Synovial chondromatosis is a rare condition of unknown aetiology. A literature search was performed to identify studies describing outcome after surgical treatment of synovial chondromatosis of the hip. Thirteen studies including two hundred-ninety patients could be included. Mean follow-up was fifty-six months. Seven out of two hundred-ninety developed a complication after surgical resection of the lesion. Recurrence rate of synovial chondromatosis is about 19%. Malignant transformation of synovial chondromatosis to chondrosarcoma is extremely rare. No wound infections were reported and avascular necrosis of the femoral head occurred in one patient who was treated with dislocation of the hip during surgery. After resection of synovial chondromatosis excellent functional outcome can be expected.

Posterior interosseous nerve palsy caused by synovial osteochondromatosis of the elbow analyzed by three-dimensional reconstruction: a case report

Background

Synovial osteochondromatosis, a benign tumor consisting of cartilage and bone, generally presents as multiple osteochondral or chondral nodules. Peripheral nerve palsy caused by synovial osteochondromatosis is rare. Three-dimensional reconstruction based on magnetic resonance imaging shows the specific shape and location of the tumor and its relation to the nerve.

Case presentation

We describe a case of posterior interosseous nerve palsy caused by synovial osteochondromatosis of the elbow in a 66-year-old Japanese man. A three-dimensional reconstructed image based on magnetic resonance imaging was used to determine the location and shape of the giant tumor, which was composed of bone and cartilage. After surgical resection of the giant tumor and neurolysis of the posterior interosseous nerve, he fully recovered from nerve palsy 9 months postoperatively. There was no recurrence of the lesion 1 year postoperatively.

Conclusion

Synovial osteochondromatosis that causes posterior interosseous nerve palsy has a characteristic morphology and location, that is, a giant tumor located anterior to the humeroradial joint, as revealed by three-dimensional magnetic resonance image reconstruction.

Extraarticular Synovial Chondromatosis: Review of Epidemiology, Imaging Studies, Microscopy and Pathogenesis, with a Report of an Additional Case in a Child

A rare benign condition of uncertain etiology and pathogenesis, Synovial Chondromatosis (SC) is most often seen intraarticularly in adults but only a handful of cases have been reported extraarticularly in children. Symptoms and physical signs consist of pain, swelling, and osteoarthritic changes related to a mass effect. Here we discuss the case of a 9-year-old boy with documented SC of the knee and critically review the Epidemiology, Clinical Presentation, Gross Anatomy and Microscopic Histopathologic Features as well as the role of Imaging Studies in Diagnosis. In addition, this paper reviews Current Pathogenetic Concepts including the infrequent but distinct possibility of malignant transformation.

Total Knee Arthroplasty in Severe Synovial Osteochondromatosis in an Osteoarthritic Knee

Synovial osteochondromatosis (SO) can occur idiopathic or secondary to osteoarthritis. SO can be easily diagnosed with plain film radiography and clinical findings. In case of disabling osteoarthritis, total knee arthroplasty and removal of all corpora libra are indicated. We present a 71-year-old woman with significant osteoarthritis and severe SO intra-articular and in the suprapatellar bursa of the right knee. Total knee arthroplasty, extraction of the loose bodies, and partial synovectomy were performed. During a 2.5-year follow-up, the patient regained full function of her affected knee and there was no recurrence of SO. We choose to present this case to show the extensiveness SO can occur in. Our advice is to remove all the loose bodies carefully to prevent damage to the prosthesis. During follow-up, special attention should be paid to prevent recurrence of SO. When recurrence is associated with rapid growth or destruction of joints, malignant reoccurrence must be considered.

Solitary synovial chondromatosis arising in the gluteus maximus bursa: computed tomography and magnetic resonance imaging findings

Chondral tumors in soft tissue are referred to as soft-tissue chondromas or extraskeletal chondromas, or as synovial chondromatosis if they arise in synovial tissue. We report the case of a 29-year-old man with synovial chondromatosis, also called synovial osteochondromatosis, which appeared in a solitary and extra-articular form. On magnetic resonance imaging (MRI) and computed tomography, the central portion of the tumor showed similar characteristics to bone marrow, despite the absence of any connection to adjacent bone. T2-weighted imaging displayed marked peripheral hyperintensity consistent with a cartilaginous area. These findings suggested the presence of enchondral ossification and were similar to those of skeletal osteochondroma, with the exception of the absence of attachment to bone. MRI is useful for distinguishing solitary synovial chondromatosis from other lesions, such as myositis ossificans, extraskeletal chondrosarcoma, and parosteal osteosarcoma.

Giant Solitary Synovial Osteochondroma of the Subtalar Joint

A rapidly progressing calcified mass was found in the left sinus tarsi in a 12-year-old female after a trivial ankle sprain. The lesion mimicked an aggressive lesion clinically and radiographically. Ultrasound-guided biopsy confirmed the diagnosis of a synovial chondroma. Excision of the tumor and partial synovectomy were performed. The histologic diagnosis was a solitary synovial osteochondroma. The condition had not recurred after a follow-up period of 12 months.

Intra-articular giant synovial osteochondroma: case reports of the ankle and knee joint

Two cases of giant intra-articular osteochondromas (knee and ankle joint) are reported; pathologically they are rare representations of synovial chondromatosis. A 17-year-old man presented with a tumorous mass which had been localized in his left ankle for many years, increasing in volume during the last months. The lesion was removed by posteromedial ankle arthrotomy. The second case was observed in a 39-year-old woman with a slow-growing mass in her right knee joint. The lesion was removed from the Hoffa fat pad by open anteromedial arthrotomy.

A popliteal giant synovial osteochondroma mimicking a parosteal osteosarcoma

Both giant synovial osteochondroma and parosteal osteosarcoma are rare musculo-skeletal tumors, often localized in the vicinity of the knee. Misdiagnosis of a malignant bone tumor can entail fatal consequences. Etiology of giant synovial osteochondroma is widely unsolved but is believed to originate from synovial chondromatosis, a mostly benign metaplasia of the synovial membrane. Parosteal osteosarcoma is a low-grade surface osteosarcoma with a propensity of local recurrence and the potential of distant metastasis and therefore requiring a different therapeutical approach. We report the case of a popliteal giant osteochondroma mimicking a parosteal osteosarcoma. Relevant facts of this rare entity regarding pathogenesis, treatment, and differential diagnoses will be discussed.

[Tumor-like diseases of the knee joint]

CLINICAL/METHODICAL ISSUE

Radiological diagnostics of tumor-like lesions of the knee joint.

STANDARD RADIOLOGICAL METHODS

Magnetic resonance imaging (MRI), computed tomography (CT) and X-ray imaging.

PERFORMANCE

Up to now there have been no studies regarding sensitivity and specificity of the various diagnostic tools (MRI, CT, X-ray) for the visualization of soft tissue tumors of the knee.

PRACTICAL RECOMMENDATIONS

The method of first choice for detecting soft tissue tumors and tumor-like lesions in the knee joint is MRI.

Giant solitary synovial osteochondromatosis of the elbow causing ulnar nerve neuropathy: a case report and review of literature

INTRODUCTION

Giant or solitary osteochondroma is part of a rare disorder known as synovial osteochondromatosis. It forms part of a spectrum of disease characterized by metaplastic changes within the joint synovium that are eventually extruded as loose bodies. It has been suggested that solitary synovial osteochondroma forms as progression of synovial osteochondromatosis through a process of either coalescence of multiple smaller bodies or the growth of a dominant synovial osteochondroma. Previous studies have shown that it occurs as a late phase of the disease. We report a rare case of giant synovial osteochondromatosis at the elbow causing ulnar nerve neuropathy and mechanical symptoms which has not been previously reported in the literature.

CASE REPORT

We report a case of a 56 year old Western European gentleman who presented with ulnar nerve neuropathy and swelling behind the elbow. The patient underwent MR imaging and subsequent biopsy that demonstrated synovial osteochondromatosis. Initially the patient declined surgery and opted for a watch and wait approach. Five years later he returned with worsening symptoms and underwent successful surgical resection of a giant solitary synovial osteochondroma.

CONCLUSION

The unique outcome in our patient despite the long interval between presentation and surgical treatment resulted in early full resolution of symptoms within a short period. It may suggest an improved prognosis as compared to multiple synovial osteochondromatosis in terms of mechanical and neurological outcomes.

Arthroscopic management for synovial chondromatosis of the temporomandibular joint: a retrospective review of 33 cases

PURPOSE

To present clinical, radiologic, and arthroscopic results of patients with synovial chondromatosis of the temporomandibular joint; to introduce a technique for removal of loose bodies in different areas; and to summarize the indications of therapeutic arthroscopy according to the magnetic resonance imaging (MRI) features.

PATIENTS AND METHODS

From April 2001 to April 2010, 33 consecutive patients underwent arthroscopy. Their demographics, clinical manifestations, imaging studies, arthroscopic findings, treatments, and outcomes were reviewed.

RESULTS

The predominant symptoms were pain, limitation of mouth opening, and joint sounds. Obvious joint effusion was shown on MRI in 21 of 33 patients. Mass lesions were shown on MRI in 29 of 33 cases. The presence of loose bodies was shown in 31 cases under an arthroscope. Synovial hyperplasia was noted in 12 patients. Bony erosion of the articular surface was discovered in 11 patients. Thirty-two patients underwent therapeutic arthroscopy. Smaller loose bodies were commonly removed with joint lavage or biopsy forceps in 24 patients. Fragmentation with forceps or a wider additional incision was applied to remove larger loose bodies in 7 patients. Debridement was applied to remove intrasynovial lesions in 7 patients. Coblation was used to remove the hyperplastic synovium in 10 of 32 patients. Eight patients were lost to follow-up. The mean follow-up period was 38 months. No recurrence was suspected clinically and radiologically.

CONCLUSIONS

Therapeutic arthroscopy was appropriate for patients with separate mass lesions and no extra-articular extension. Surgical treatment comprised thorough removal of loose bodies and affected synovial tissues.

Giant solitary synovial chondromatosis of the temporomandibular joint with intracranial extension

Synovial chondromatosis are rare entities but are well-described lesions in the literature that can affect many joint areas of the body. A case of tumoral synovial chondromatosis involving the temporomandibular joint with intracranial extension through mandibular fossa is reported. As long as there was significant infratemporal and extradural invasion of the middle and posterior fossa, a transtemporal and infratemporal approach was performed and total removal of the lesions was achieved. A brief review of skull base synovial chondromatosis is presented.

[Synovial chondromatosis]

Primary articular synovial chondromatosis is a benign, self-limiting neoplastic process in which hyaline cartilage nodules form in the synovial tissue. The disease most frequently affects the knee in men, followed by the elbow. The basic feature of this disease is a metaplastic maturation of the mesenchymal cells in the synovial membrane of a joint into cartilage. These cells mature into chondroblasts and form small nodules of cartilage in the synovial membrane. These nodules subsequently enlarge and detach to lie within the joint space. They become free within the joint as multiple small cartilaginous loose bodies nourished by the synovial fluid. The chondrocytes in the loose bodies continue to multiply, and the loose bodies grow in diameter. Calcification appears in the central zone of the loose bodies, and in some cases, enchondral ossification takes place. The operative therapy depends on the stage of the disease: synovectomy with removal of chondral fragments if active intrasynovial disease is present, and removal of the multiple chondral bodies alone in cases of late inactive disease with no synovial abnormalities. Malignant transformation is unusual and can be difficult to distinguish from benign disease.

Synovial chondromatosis presenting with lumbar radiculopathy

STUDY DESIGN

A case report of lumbar synovial chondromatosis with radiculopathy.

OBJECTIVE

To report a case of synovial chondromatosis of a lumbar facet joint that extended into the spinal canal and compromised the lumbar nerve root and raised spinal surgeons' awareness of the possibility of this unusual clinical problem.

SUMMARY OF BACKGROUND DATA

Synovial chondromatosis is an uncommon disorder characterized by the formation of multiple cartilaginous nodules in the synovium of a facet joint. It most commonly affects large joints. Synovial chondromatosis in the spine is rare and there is no previous report of associated lumbar radiculopathy.

METHODS

A 24-year-old woman presented with low back pain and right sciatica lasting 5 months. There was no objective weakness. Computed tomography scans showed multiple calcified nodules anterior and medial to the right apophyseal joint of L5-S1 and extending into the spinal canal. Magnetic resonance imaging showed a lobulated, heterogeneous enhancing extradural mass arising from the anteromedial aspect of the right L5-S1 facet joint. The lesion was removed in multiple pieces with curette after exposure of the corresponding intervertebral space through a conventional interlaminar approach. The histologic examination showed nodules of hyaline cartilage beneath the synovial cell lining.

RESULTS

The patient was completely free of low back pain and right sciatica 5 days after the surgery. All neurologic tests were normal from that point onwards.

CONCLUSION

Synovial chondromatosis may compromise lumbar nerve roots when it extends into the spinal canal from the facet joint. Although synovial chondromatosis of the lumbar spine is rare, it should be included in the differential diagnosis of radiculopathy.

Synovial chondromatosis of the lumbar spine with compressive myelopathy: a case report with review of the literature

Synovial chondromatosis has been rarely reported to occur in the spine with only one case found in the lumbar spine. We describe another case of synovial chondromatosis in the lumbar spine in a 41-year-old man who presented with compressive myelopathy. The tumor was located in the left ventrolateral corner of the epidural space just below the L(4)-L(5) intervertebral space. Besides being extremely rare, our case was unusual in that the juxtaposed facet joint was radiologically normal.

Imaging of Synovial Chondromatosis with Radiologic-Pathologic Correlation

Primary synovial chondromatosis represents an uncommon benign neoplastic process with hyaline cartilage nodules in the subsynovial tissue of a joint, tendon sheath, or bursa. The nodules may enlarge and detach from the synovium. The knee, followed by the hip, in male adults are the most commonly involved sites and patient population. The pathologic appearance may simulate chondrosarcoma because of significant histologic atypia, and radiologic correlation to localize the process as synovially based is vital for correct diagnosis. Radiologic findings are frequently pathognomonic. Radiographs reveal multiple intraarticular calcifications (70%-95% of cases) of similar size and shape, distributed throughout the joint, with typical "ring-and-arc" chondroid mineralization. Extrinsic erosion of bone is seen in 20%-50% of cases. Computed tomography (CT) optimally depicts the calcified intraarticular fragments and extrinsic bone erosion. Magnetic resonance (MR) imaging findings are more variable, depending on the degree of mineralization, although the most common pattern (77% of cases) reveals low to intermediate signal intensity with T1-weighting and very high signal intensity with T2-weighting with hypointense calcifications. These signal intensity characteristics on MR images and low attenuation of the nonmineralized regions on CT scans reflect the high water content of the cartilaginous lesions. CT and MR imaging depict the extent of the synovial disease (particularly surrounding soft-tissue involvement) and lobular growth. Secondary synovial chondromatosis can be distinguished from primary disease both radiologically (underlying articular disease and fewer chondral bodies of variable size and shape) and pathologically (concentric rings of growth). Treatment of primary disease is surgical synovectomy with removal of chondral fragments; recurrence rates range from 3% to 23%. Malignant transformation to chondrosarcoma is unusual (5% of cases) and, although difficult to distinguish from benign disease, is suggested by multiple recurrences and marrow invasion. Recognizing the appearances of primary synovial chondromatosis, which reflect their underlying pathologic characteristics, improves radiologic assessment and is important to optimize patient management.

Histologic classification of loose bodies in osteoarthrosis

BACKGROUND

Histologically based analyses of the nature and origin of loose bodies occurring in osteoarthrosis have been few, and further study is warranted.

METHODS

We histologically examined 84 loose bodies and 9 related lesions (synovial membrane nodules) surgically removed from 24 joints of 24 patients with osteoarthrosis.

RESULTS

The 84 loose bodies included 48 chondral loose bodies (type I), 26 osteochondral loose bodies (type II), and 10 osseous loose bodies (type III). The 26 osteochondral loose bodies (type II) could be subdivided into 8 composed of cartilage with enchondral ossification (type IIa), 11 consisting of mature bone covered by cartilage without enchondral ossification (type IIb), and 7 made up of mature bone and partially articular cartilage or hyaline cartilage (type IIc). Synovial membrane nodules could be also divided into three types in the same manner as loose bodies. Many type IIa, type IIc and type III loose bodies and all synovial membrane nodules showed blood vessels containing red blood cells, as well as osteoclasts. The type I and type IIb loose bodies, however, did not show them.

CONCLUSIONS

It is well known that loose bodies grow from proliferation of cartilage without blood supply in the joint cavity, and that enchondral ossification is able to develop only under the condition of having a blood supply. As synovial membrane nodules were also classified to the same types as loose bodies and more than half of osteochondral and osseous loose bodies contained blood vessels with red blood cells, the loose bodies were thought to be caught in the synovial membrane and to be modified as the result of a blood supply. Considering the results of this study, the various histologic characteristics of loose bodies in osteoarthrosis resulted from modifications including cartilage proliferation in the joint cavity and enchondral ossification in the synovial membrane.

Giant synovial osteochondromatosis of the acromio-clavicular joint in a child. A case report and review of the literature

Primary intra-articular synovial chondromatosis represents an uncommon condition involving mainly the large joints predominantly of middle-aged adults. We herein document the first case of synovial chondromatosis affecting the acromio-clavicular joint of a 10-year-old girl, characterized by a solitary huge intra-articular osteochondromatous body (giant synovial chondromatosis) that had caused dislocation and deformation of the lateral portion of the clavicle. Successful surgical treatment consisted of removal of the osteochondral body and replacement of the clavicle by fixation with a K-wire.

Synovial osteochondromatosis presenting as a mass in the buttock

A 42-year-old woman, who had received a radiologic diagnosis of synovial osteochondromatosis many years before, was examined for a painful right hip and a large immobile mass in the right buttock. Findings of radiologic and scintigraphic imaging were consistent with synovial osteochondromatosis. The patient underwent arthrotomy and excision of the large mass and several smaller masses to control pain and to identify possible malignant change.

Multiple giant synovial chondromatosis of the knee

This report describes an unusual presentation of monoarticular synovial chondromatosis of the knee. In this case, multiple giant chondroid nodules presented as a painless soft tissue mass. There was no calcification but bony erosion was seen on MR scan. Such lesions may mimic a malignant neoplasm and pose a diagnostic problem.

Synovial chondroma of the ankle in a young child after recent trauma: CT and MR features

We report a case of synovial chondroma of the left ankle in an 11-year-old boy presenting with soft tissue swelling after recent trauma. The noncalcified or nonossified intraarticular chondroma arising from metaplastic synovium has characteristic imaging appearance on computed tomography (CT) and magnetic resonance imaging (MRI). A lobulated mass of fluid-like density and signal intensity along with internal septa are characteristic features on CT and MRI. The knowledge of CT and MRI features of noncalcified or nonossified synovial chondroma is important to distinguish from the simple or complicated effusion, hemarthrosis, or other synovial process.

Synovial chondromatosis in a facet joint of a cervical vertebra

STUDY DESIGN

A case report of a cervical facet joint synovial chondromatosis.

OBJECTIVES

To correlate the radiologic and histologic features of vertebral synovial chondromatosis with review of the literature.

SUMMARY OF BACKGROUND DATA

Only two previous cases of vertebral facet joint synovial chondromatosis were found in a review of the English language medical literature.

METHODS

A 39-year-old woman had severe cervical pain associated with neurologic signs and symptoms in the left upper extremity. Computed tomographic and magnetic resonance imaging studies were performed.

RESULTS

Imaging studies showed lytic defects in the laminae of C3 and C4, with intermediate T1 and high T2 signal intensities. The diagnostic impression was that of a lymphangioma or synovial cyst. A laminectomy showed synovial tissue in both the C3-C4 facet joint and the lamina bone. Histologic examination disclosed synovial chondromatosis.

CONCLUSIONS

Synovial chondromatosis of the vertebral spine is quite rare, this being only the third reported example. Direct invasion of the cancellous bone, as in this case, also is a very uncommon feature of chondromatosis. It is emphasized that when radiologic studies demonstrate a lesion with cartilaginous characteristics within or juxtaposed to a joint, synovial chondromatosis, despite its rarity, should be included in the differential diagnosis, regardless of the anatomic site.

Monoarticular synovial lesions: radiologic pictorial essay with pathologic illustration

A wide variety of common focal monoarticular synovial lesions may be encountered on imaging studies. A multi-modality approach to these lesions, with appreciation of the differing appearances, can often yield the correct diagnosis. This pictorial essay demonstrates and describes the imaging with illustration of pathologic findings in a spectrum of conditions.

Ultrasound appearance of synovial osteochondromatosis of the shoulder

This case report demonstrates the ultrasound appearance of synovial osteochondromatosis of the shoulder, along with plain film radiographic, computed tomographic, and pathologic correlation. Because of recent renewed interest in the use of ultrasonography in the evaluation of musculoskeletal disease, such as rotator cuff arthropathy or suspected intra-articular loose body, opportunities to diagnose synovial osteochondromatosis with this modality have become more frequent.

Chromosome rearrangements in synovial chondromatous lesions

Short-term cultures from one synovial chondroma and three cases of synovial chondromatosis, a lesion for which no previous karyotypic information exists, were cytogenetically analysed. Whereas the chondroma displayed the relatively simple karyotype 46,XY,add(12)(q13),der(17)t(12;17)(q13;q21), more complex changes were found in the three cases of chondromatosis: case 1, 47,XY,der(1)inv(1)(p13q25)del (1)(q25q32), t(1;12)(q25;q13), + 5,der(12)add(12)(p11)t(1;12)(p22;q13); case 2, 47,XY,add(10)(q26), + 20/46 idem,-6/46,XY,t(2;4)(q33;q21), add(21)(p11); and case 3, 44,XY,add(1)(p36), del(1)(p13p22),add(6)(p25), del(7) (q22q32),del(10)(q21),add(11)(q13),-17,-18. The cytogenetic findings strongly suggest that synovial chondro-matosis is a clonal proliferation. Apart from a near-diploid chromosome number, the only recurrent cytogenetic features among the four cases were loss of band 10q26 and rearrangements of 1p13 and 12q13, found in two cases each. While chromosome bands 1p13 and 10q26 have not been reported to be involved in other types of benign chondromatous lesions, the 12q13-15 segment is recurrently rearranged in a variety of chondromatous tumours, e.g. pulmonary chondroid hamartomas. The present finding of translocations affecting band 12q13 in two of the cases emphasises that, irrespective of the anatomical localisation of the tumours, rearrangements of genes in 12q13-15 are important in the development of a large subset of benign and malignant cartilage-forming tumours.

Synovial chondromatosis presenting as painless soft tissue mass--a report of 19 cases

Primary synovial chondromatosis is a disorder of joints, tendon sheaths and bursae characterized by the formation and growth of cartilaginous nodules. It usually presents clinically with joint symptoms and is frequently associated with intra-articular loose bodies. A large soft tissue mass is an unusual presentation which, both clinically and radiologically, raises the suspicion of malignancy. Nineteen cases of synovial chondromatosis presenting as soft tissue tumours were reviewed. They were all adjacent to joints but with no joint symptoms. Histology showed the typical features of benign synovial chondromatosis, including foci of cartilage cells showing cytological atypia. This is well recognized and does not indicate malignancy. Clinical follow up confirmed this with local recurrence only in three patients. It is important to be aware of this unusual presentation as the alternative diagnosis of a chondrosarcoma, as initially diagnosed in some of these cases, has major implications regarding the treatment of these patients.