We reported 5 cases of stress fracture in RA patients during 1989-1991, in which 3 cases of femoral neck fracture were treated surgically and 2 cases of pubic fracture conservatively. They were all female and evaluated for their state of osteoporosis. We consider that osteoporosis, increased activity of daily living after arthroplasty and muscle imbalance are possible causes of stress fractures. Because pain arising from stress fractures is easily mistaken for rheumatoid synovitis, clinical suspicion and close follow-up are nessesary for RA patients with persistent hip pain.
