Transient osteoporosis of the hip.

Transient osteoporosis of the hip (TOH) is not an uncommon condition, usually with a benign course. The syndrome classically affects women during the last trimester of pregnancy, but also middle aged men. Recently, TOH has been described in non pregnant women. The pathophysiology of the disease is uncertain, though several hypotheses have been suggested. Joint pain is the main symptom. TOH is a self-limited condition, which resolves spontaneously with complete recovery within several months in most cases.