Hip osteoarthritis: where is the pain?

Abstract

Hip pain referred below the knee is common with a degenerate hip joint and follows the distribution of the saphenous nerve, which branches from the femoral nerve. Radiographic deterioration of a hip joint does not correlate with pain distribution or patient dysfunction as measured by the Oxford Hip Score.

Does Ipsilateral Knee Pain Improve after Hip Arthroplasty?

“…Our observations suggest 55% of our patients undergoing hip arthroplasties had IKP, which was high compared with 17.6% for the contralateral knee. Khan et al [21] suggested a similar phenomenon with 68.6% and 50.9% of patients scheduled to undergo hip arthroplasties reporting anterior and posterior knee pain, respectively, before surgery. Although IKP is frequent in patients with severe hip disease, the direct cause remains unknown.…”

“…Most previous studies have been case reports [8, 10-13, 15, 16]. Only several observational reports describe the distribution of the referral pain of hip disease [21,24,32]. We therefore asked: (1) if hip disease was associated with preoperative IKP and (2) does IKP improve after hip arthroplasty?…”

“…Ipsilateral knee pain (IKP) is commonly associated with intraarticular hip disease [11,14,20,21,24,26] and other sources of pain referred from the lumbar spine and pelvic area. Osteoarthritis (OA) of the knee is not an uncommon cause of IKP [28].…”

“…Referred pain to the knee from hip disease is particularly common in the pediatric population and has been identified as a cause for delayed diagnosis of hip problems such as developmental dysplasia of the hip, Perthes' disease, slipped capital femoral epiphysis, septic arthritis, and others [14,18,27]. Others have reported a similar referred pain in adult patients with hip OA [8,21,24]. The accepted explanation of this phenomenon is that hips and knees get innervation from the femoral and obturator nerves.…”

Isolated Knee Pain: A Case Report Highlighting Regional Interdependence

“…24,42 This is more common in adolescents. In adults, the presence of knee pain without concurrent complaints from the hip is not seen as often.…”