Atraumatic osteonecrosis of the distal radius and ulna: case series and review.

Purpose: Atraumatic multifocal osteonecrosis is defined as the occurrence of atraumatic osteonecrosis in 3 or more anatomic locations, and it is rare. We identified 6 patients with osteonecrotic lesions in the distal ulna, radius, or both. The purposes of this study were to describe the clinical manifestations of atraumatic multifocal osteonecrosis affecting these bones, to identify risk factors for developing the disease in these locations, and to evaluate the success of treatment by percutaneous drilling.

Methods: A total of 10 wrists in 6 women with a mean age of 41 years had symptomatic osteonecrosis. Patients were treated by percutaneous drilling after they had failed nonoperative modalities. Clinical evaluation included preoperative and postoperative Michigan Hand Questionnaire scores plain radiographs, and MRI evaluations were performed to characterize the disease. The incidence of risk factors was recorded.

Results: There was disease occurrence in the radius in all 10 wrists and in the ulnas of 4 wrists. All patients presented with symptomatic osteonecrosis of the large joints (primarily knee or hip), presumably secondary to corticosteroid use. These patients later developed symptomatic pain in the distal ulna, radius, or both that impaired daily activities. Other risk factors included alcohol or tobacco use, blood dyscrasias, and systemic lupus erythematosus. Treatment consisted of percutaneous drilling of the distal radius (and ulna when affected). One patient required additional bilateral drillings and had further improvement in her Michigan Hand Questionnaire scores. At a mean follow up of 35 months, there was no disease progression as evident radiographically.

Conclusions: The distal radius and ulna are rare sites of osteonecrosis associated with multifocal disease. The clinical presentation and risk factors are similar to osteonecrosis in the large joints. Magnetic resonance imaging identifies necrotic lesions. The present study suggests that disease in these sites can be safely and effectively treated with percutaneous drilling.

Type Of Study/level Of Evidence: Therapeutic IV.