Distribution of hip pain in osteoarthritis patients secondary to developmental dysplasia of the hip

Our aim was to clarify the distribution of hip pain in patients with osteoarthritis of the hip secondary to developmental dysplasia of the hip (DDH). We retrospectively studied 443 hips in 369 patients with osteoarthritis secondary to DDH; mean age was 61 years, and follow-up rate was 84 %. Hip pain was defined as preoperative pain that was relieved 3 months after total hip arthroplasty. Distribution of pain originating in the hip was 89 % (393 hips) to the groin, 38 % (170 hips) to the buttock, 33 % (144 hips) to the anterior thigh, 29 % (130 hips) to the knee, 27 % (118 hips) to the greater trochanter, 17 % (76 hips) to the low back, and 8 % (34 hips) to the lower leg. When the groin, buttock, and greater trochanter were combined as the hip region, 95 % (421 hips) of pain was located in the hip region. On the other hand, when the anterior thigh, knee, lower leg, and low back were combined as the referral region, 55 % (242 hips) showed referred pain. We suggest that rheumatologists be aware of hip disease masquerading as knee pain or low back pain.