The ghost joint: transient osteoporosis of the hip.

Seven adult patients identified as having idiopathic transient osteoporosis of the hip (TOH) are reported. TOH is an uncommon entity, most often seen in women during the third trimester of pregnancy and in middle-aged men. It is characterized by groin pain, limited hip range of motion, nonspecific laboratory findings, localized radiographic evidence of osteopenia, and spontaneous recovery usually within two to nine months. Diagnosis remains dependent on clinical recognition and x-ray confirmation. Radioisotope scanning aids in the diagnosis; both bone and synovial biopsies are often less productive. Treatment consists of joint protection with limited weight bearing, range of motion exercise, progressive ambulation, and analgesics. An awareness of TOH facilities appropriate diagnosis and treatment and curtails unnecessary diagnostic procedures.