Elastofibroma of the neck

Elastofibromas are benign lesions of the chest wall. We describe the first reported case of elastofibroma in the neck. Imaging features as well as location of the lesion were atypical. On computed tomography and magnetic resonance imaging the lesion contained a marked preponderance of fat, because the lesion arose within fat. Received: 12 November 1998 Revision requested: 18 November 1998 Revision received: 16 August 1999 Accepted: 24 August 1999     

Dumb-bell-type teratoma in the lumbar spine

We report a case of a lumbar teratoma in a 50-year-old woman. The teratoma showed a dumb-bell-type expansion at the level of the left L3/4 foramen with massive erosion of the L3 vertebral body. MRI revealed inhomogeneous signal changes in the tumor, which were histologically compatible with a mixture of bone, muscle, fat, and cyst containing sebaceous material. Complete resection of the tumor and spinal arthrodesis with pedicle screw fixation was necessary to obtain stability of the affected spinal segment. Received: 30 July 1999 Revision requested: 24 August 1999 Revision received: 11 October 1999 Accepted: 12 October 1999     

MR imaging after therapeutic injection of the subacromial bursa

Objective. As a therapeutic injection into the subacromial bursa (SAB) is commonly performed for impingement syndrome, it is important to know whether this fluid can be retained for a period of time and cause confusion with a pathologic collection of fluid. This study identifies and describes the appearance of recent subacromial injection using MR imaging, and the appearance of a potential complication. Design and patients. Fourteen asymptomatic shoulders were studied with MR imaging using fast spin echo T2-weighted imaging (1.5 T) prior to injection with 7 cm³ of xylocaine. Four shoulders had subacromial fluid and were eliminated from the study. The remaining 10 (9 men, 1 woman; age range 27–36 years, average age 33 years) were then re-imaged immediately, and at 6, 12 and 24 h after the injection or until fluid resolved. Each set of images was reviewed for the presence of fluid in the SAB and for additional abnormalities. Results. Fluid was identified in all subjects in the SAB in the immediate, 6 and 12 h post-injection images. At 24 h, fluid was not identified within the SAB in eight of 10 patients. In one patient fluid resolved in 48 h. The other continued to demonstrate fluid in the SAB and in the joint as well as abnormal signal in the infraspinatus muscle from a presumed myositis. Imaging was performed up to 10 days after the injection in this patient. Conclusions. It is known that fluid identified in the SAB without evidence of a cuff tear may be due to bursitis. However, if MR imaging is performed within 24 h of injection, the presence of the fluid may be iatrogenic. In addition, the history of recent therapeutic injection is very important as complications such as myositis can occur as a result of the injection. Knowledge of injection prior to imaging is vital for accurate interpretation of MR shoulder examinations. Received: 14 May 1999 Revision Requested: 22 July 1999 Revision Received: 11 August 1999 Accepted: 18 August 1999     

Extraskeletal osteochondroma of the foot

A case of pathologically proven extraskeletal osteochondroma is presented with magnetic resonance imaging (MRI), computed tomography (CT), bone scan and radiographic findings. The diagnosis of extraskeletal osteochondroma should be considered when a discrete, ossified mass is localized in the soft tissues of the distal extremities. Nomenclature surrounding this entity is controversial and is discussed. Received: 22 March 1999 Revision requested: 26 April 1999 Revision received: 22 May 1999 Accepted: 24 May 1999     

Premature epiphyseal fusion and degenerative arthritis in chronic recurrent multifocal osteomyelitis

A 9-year-old boy was diagnosed with chronic recurrent multifocal osteomyelitis affecting multiple sites. During an 8-year follow-up he developed premature closure of a distal radial epiphysis and degenerative changes in the adjacent radiocarpal joint. Received: 26 July 1999 Revision requested: 24 August 1999 Revision received: 27 September 1999 Accepted: 8 October 1999     

Giant distal humeral geode

We describe the imaging features of a giant geode of the distal humerus in a patient with rheumatoid arthritis, which presented initially as a pathological fracture. The value of magnetic resonance imaging in establishing this diagnosis is emphasized. Received: 8 July 1999 Revision requested: 24 August 1999 Revision received: 25 October 1999 Accepted: 26 October 1999     

Sclerotic bone metastases from sarcomatoid renal cell carcinoma

We present a case of sarcomatoid renal cell carcinoma with multiple sclerotic skeletal metastatic lesions. Renal cell carcinoma is frequently metastatic at presentation, with a high incidence of skeletal involvement, classically described as osteolytic. However, sclerotic or osteoblastic metastatic skeletal lesions from renal cell carcinoma are rare, with only two previous reports identified in the literature, neither of which involved the sarcomatoid variant of renal cell carcinoma. In our case the sclerotic metastases were characterized by bone scan, computed tomography (CT), magnetic resonance imaging (MRI), and histologic analysis. Received: 8 April 1999 Revision requested: 27 May 1999 Revision received: 24 June 1999 Accepted: 29 June 1999     

Intra-articular regional migratory osteoporosis of the knee

We report a case of lntra-articular regional migratory osteoporosis of the knee in a 53-year-old man. The case demonstrates an unusual pattern of migration of the marrow edema within the knee joint. This phenomenon has received scant attention in the radiological literature. Received: 9 July 1999 Revision requested: 24 August 1999 Revision received: 6 October 1999 Accepted: 8 October 1999     

Vertebral intra-osseous chordoma or giant notochordal rest?

Chordomas of the lumbar vertebral bodies are rare. We report an unusual case of an entirely intra-osseous chordoma of the fifth lumbar vertebra treated by vertebrectomy. Conventional radiographs and scintigraphy were normal. The lesion was well visualised by MR imaging, but showed only slight sclerosis on CT. We give our reasons for making a diagnosis of chordoma rather than giant notochordal rest and discuss the problems of management resulting from this diagnostic dilemma. Received: 25 February 1999 Revision requested: 2 March 1999 Revision received: 15 March 1999 Accepted: 18 March 1999     

Progressive destructive vertebral sarcoid leading to surgical fusion

Skeletal sarcoidosis is rare. This report describes a 31-year-old African American man who presented with a destructive osteolytic lesion of C2 and another lesion in a rib. The lesion at C2 was treated with corpectomy and bone graft. Four months later the lesion recurred and a new lesion was discovered in the cervical vertebral column. The patient declined surgery for instability for another 3 months, choosing to remain in a halo. Seven months following the initial operation, a technetium bone scan showed spread of the disease to the calvarium and thoracic and lumbar vertebrae. The patient had no symptoms referable to these sites. The patient agreed to have his neck fused at this point. For the next 10 months, the patient was on steroids and a further new lesion appeared at L5 without localizing signs or symptoms. The patient declined further evaluation over the next 12 months and is now considered lost to follow-up. Received: 29 July 1999 Revision requested: 26 August 1999 Revision received: 1 September 1999 Accepted: 2 September 1999     

Post-Paget telangiectatic osteosarcoma of the skull

Sarcomatous transformation is the most dreaded complication of Paget’s disease. We report on a case of post-Paget telangiectatic osteosarcoma of the skull, a variant of osteogenic osteosarcoma, in a 79-year-old woman. We discuss the radiological pattern in relationship to the differential diagnosis. Received: 27 July 1998 Revision requested: 24 August 1998, 23 December 1998 Revision received: 25 November 1998, 12 April 1999 Accepted: 13 April 1999     

Intramuscular metastasis from malignant melanoma: MR findings

We present a rare case of intramuscular metastasis from malignant melanoma. The lesion showed intermediate to high signal intensity on T1-weighted magnetic resonance (MR) images and mixed signal intensities containing high and low signals on T2-weighted images. The signal intensity on T1-weighted images, which is due to the paramagnetic effect of melanin, is a characteristic MR finding of this entity. Received: 10 June 1999 Revision requested: 7 July 1999 Revision received: 9 August 1999 Accepted: 9 August 1999     

Lumbar and radial bone mineral density in children and adolescents with X-linked hypophosphatemia: evaluation with dual X-ray absorptiometry

Objective. To evaluate the bone mineral status of children being treated for X-linked hypophosphatemia, including potential differences between cortical bone in the radial diaphysis and combined cortical and trabecular bone in the lumbar spine. Design and patients. Forty-four bone mineral evaluations were performed in 11 children and adolescents with X-linked hypophosphatemia. Bone mineral density (BMD) of the lumbar spine and the radial diaphysis were measured by dual X-ray absorptiometry (DXA), second metacarpal cortical thickness was measured on hand radiographs, and these results were expressed as Z-scores (standard deviations from the mean). Results. For the 11 initial examinations, Z-scores (mean±SD) were: radial BMD, –2.73±1.15, lumbar BMD, +1.28±1.53; and cortical thickness, –2.21±0.95. Lumbar BMD Z-scores were significantly greater than those for radial BMD and cortical thickness. On follow-up examinations there was a mild increase in radial BMD and decrease in lumbar BMD. Although these changes were statistically significant, they were quite small and the discordance between radial and lumbar BMD was not corrected. Conclusions. Children and adolescents who are being treated for X-linked hypophosphatemia manifest a bone mineral disorder characterized by decreased BMD in the appendicular skeleton and increased BMD in the lumbar spine. Although current therapy is successful in its anti-rachitic effects, it does not correct this bone mineral disorder and additional therapeutic trials should be considered. Received: 28 May 1999 Revision requested: 22 July 1999 Revision received: 18 October 1999 Accepted: 26 October 1999     

Radiography in osteoarthritis of the knee

Osteoarthritis (OA) is a multifactorial process affecting cartilage and subchondral bone. Conventional radiographs are inexpensive and readily available. The increased knowledge with regard to interpreting weightbearing radiographs of the tibiofemoral joint and axial radiographs of the patellofemoral joint will enable these examinations to remain competitive techniques compared with more expensive and sophisticated methods, such as MR imaging, when investigating knee pain to establish the diagnosis and the severity of OA. Received: 21 May 1999 Revision requested: 13 July 1999 Revision received: 9 August 1999 Accepted: 12 August 1999     

Myxoma of the humerus: an exceptional site of origin

Myxoma of bone, outside of the jaws, is exceptional. We present such a tumor in the humerus and discuss the criteria for the diagnosis of myxoma. Received: 10 August 1999 Revision requested: 10 September 1999 Revision received: 14 September 1999 Accepted: 14 September 1999     

Cervical myositis ossificans traumatica: a rare location

An unusual case of myositis ossificans traumatica lesion located in the paraspinal region is reported. Despite the contiguity of the lesion with the cervical vertebrae and ominous appearance of the biopsy material, the history of antecedent trauma and computed tomography findings allowed preoperative accurate diagnosis. To our knowledge, myositis ossificans traumatica located in the cervical paraspinal region is very rare. Received: 9 March 1998; Revision received: 22 May 1998; Accepted: 12 June 1998     

Locking of metacarpophalangeal joints in a patient with acromegaly

A 39-year-old man with acromegaly exhibited locking of metacarpophalangeal (MCP) joints of both index fingers. Large osteophytes were found at the metacarpal heads by radiography and computerized tomography (CT). Magnetic resonance (MR) images revealed hypertrophy of volar plates. We suggest that these characteristic acromegalic features caused locking of MCP joints. Surgery was required on one of the joints to release the locking. Received: 17 May 1999 Revision requested: 28 June 1999 Revision received: 19 July 1999 Accepted: 21 July 1999     

Intraosseous schwannoma of the metacarpal

Intraosseous schwannoma (neurilemmoma) is an extremely rare, benign neoplasm, constituting less than 0.2% of primary bone tumors. It infrequently involves the bones of the hand. We present a case of intraosseous neurilemmoma of the metacarpal. Received: 26 July 1999 Revision requested: 16 August 1999 Revision received: 16 September 1999 Accepted: 4 October 1999     

Metadiaphyseal chondroblastoma of the thumb

Chondroblastoma is typically located in the epiphysis. Predominant metadiaphyseal location is very rare, as is involvement of the digits. We describe a case of chondroblastoma involving the metadiaphysis of the thumb. The patient was a 13-year-old boy who presented with pain and swelling of his left thumb. Radiographs showed an expanded lytic lesion involving the whole metaphysis and diaphysis of the proximal phalanx, which subsequently progressed to involve the epiphysis. Curettage and bone grafting were done. Received: 9 July 1999 Revision requested: 12 August 1999 Revision received: 1 November 1999 Accepted: 4 November 1999     

’Cable-maker’s clavicle’: stress fracture of the medial clavicle

A 50-year-old man presented with a non-traumatic painful swelling over the medial clavicle. Radiographs showed a poorly defined fracture and the possibility of an underlying pathology was raised. Computed tomography suggested a stress fracture. This prompted a further, more detailed occupational history to be obtained from the patient, which revealed a hitherto undescribed cause of clavicular stress fracture and obviated the need for further imaging or biopsy. Received: 27 December 1999 Revision requested: 17 January 2000 Revision received: 24 February 2000 Accepted: 29 February 2000