Twenty-seven cases of an unusual, poorly recognized destructive hip arthropathy with radiographic findings of rapid severe joint destruction are presented. Radiographic findings mimicked those of other disorders such as septic arthritis, rheumatoid and seronegative arthritis, primary osteonecrosis with secondary osteoarthritis, or neuropathic osteoarthropathy, but none of the patients had clinical, pathologic, or laboratory evidence of these entities. All patients underwent hip arthroplasty, and osteoarthritis was confirmed at pathologic examination. Rapid progression of hip pain and disability was a consistent clinical feature. The average duration of symptoms was 1.4 years. Radiographs obtained at various intervals before surgery (average, 18 months) in nine patients documented rapid hip destruction. Involvement was unilateral in 89% (24 of 27 cases). Twenty patients (83%) were elderly women. The authors postulate that these cases represent an uncommon, rapidly destructive subset of osteoarthritis.

Sixty-seven cases of osteoid osteoma were studied at the Hospital for Joint Diseases between 1980 and 1989. The lesions were categorized according to location: medullary, cortical, or subperiosteal and were further grouped as intracapsular and extracapsular. The histologic features of trabecular thickness, reactive bone formation, proportion of fibrovascular stroma, and ratio of osteoid and mineralized matrix were examined. The radiographic features were compared. The literature is reviewed. We include our experience with tetracycline labelling.

The middle glenohumeral ligament frequently presents variations of the normal anatomy and it is often injured in patients suffering trauma to the glenohumeral joint. The purpose of this pictorial assay is to illustrate the normal anatomy, biomechanics, normal variants and pathology of the middle glenohumeral ligament, as shown on MRI and MR arthrography of the shoulder.

Eleven subperiosteal lesions were studied. The reactive periostitis of four lesions was atypical and misleading. Four lesions had features similar to the more common intracortical variety. Three lesions occurring within the joint like other intra-articular lesions were barely seen on plain radiographs. Bone scan and CT scan were virtually diagnostic. The histopathology of these lesions was also atypical though not misleading. In conclusion, subperiosteal osteoid osteoma is a rare lesion with atypical radiographic and histopathologic features. The unusual reactive periostitis seen in several extra-articular cases may suggest other diagnoses.