Idiopathic Transient Osteoporosis of the Talus: A Cause for Unexplained Foot and Ankle Pain

A 53-year-old woman was investigated for several neoplastic, inflammatory, and infective conditions for her left foot, and ankle pain associated with swelling, which she developed unexpectedly without history of trauma or infection. Gross osteopenia in the talus raised the possibilities of several differential diagnoses, but a magnetic resonance imaging scan showed diffuse bone marrow edema in the talus. With negative infective and inflammatory markers, the condition was ultimately labeled as “transient osteoporosis.” She was reassured and followed up regularly. At the end of 12 months, she was completely asymptomatic, and her radiograph and magnetic resonance images showed significant improvement, with a normal-appearing talus and ankle joint, and there was complete resolution of bone marrow edema. Although “transient osteoporosis” of the foot is an uncommon condition, clinicians should be aware of this. Unexplained foot pain, with osteopenic bone and diffuse bone marrow edema on magnetic resonance imaging scan, is a feature of this condition. However, the diagnosis is established once other causes are excluded. The condition is self-limiting, and watchful expectancy of a normal recovery is the mainstay of treatment.