Transient osteoporosis.

Transient osteoporosis (TO) is an uncommon entity whose principal characteristic is to be a self-limited syndrome. Diagnosis is made upon clinical presentation and x-ray evidence of diffuse osteopenia around the affected joint followed by spontaneous healing after several months. When recurrent episodes occur at different times and locations it is called regional migratory osteoporosis. Magnetic resonance imaging and technetium-99 bone scan may be helpful in diagnosis during the early phase. Good results may be achieved with nonsteroidal antiinflammatory medication, protected weight bearing and physical therapy.