Hip-spine syndrome: The effect of total hip replacement surgery on low back pain in severe osteoarthritis of the hip

STUDY DESIGN. Prospective clinical study on the effect of total hip replacement surgery (THR) on low back pain (LBP) in patients with severe hip osteoarthritis. OBJECTIVE. To assess the affect of THR on LBP. SUMMARY OF BACKGROUND DATA. Hip osteoarthritis causes abnormal gait and spinal sagittal alignment and is associated with LBP. METHODS. All consecutive adults scheduled for THR in our department due to severe hip osteoarthritis were assessed by an independent investigator before surgery and 3 months and 2 years post-THR. The Harris Hip Score and the Oswestry scores were used to evaluate hip- and spine-related symptoms, respectively, as were visual analogue scales (VAS) and sagittal spinal radiographs. RESULTS. Twenty-five patients (10 males; age range, 32-84 years) were evaluated. Both spinal and hip pain and function were significantly better following THR. The mean preoperative LBP VAS score of 5.04 was 3.68 after THR (P = 0.006). The mean preoperative Oswestry score of 36.72 was 24.08 after THR (P = 0.0011). Clinical improvement was maintained and enhanced at the 2-year follow-up. The mean hip pain VAS score was 7.08 before THR and 2.52 after THR (P < 0.01). The mean Harris Hip Score was 45.74 before and 81.8 after surgery (P < 0.01). There were no changes in the radiographic measurements. CONCLUSION. Both LBP and spinal function were improved following THR. This study demonstrates the clinical benefits of THR on back pain and is the first to clinically validate hip-spine syndrome as hypothesized by Offierski and MacNab in 1983.