Does lumbar arthrodesis compromise outcome of total hip arthroplasty?

Introduction: This matched cohort study aims to determine whether the presence of a spinal arthrodesis (SA) compromises outcome of total hip arthroplasty (THA) and whether the outcome is better if THA is performed before- (THA-1(st)) or after- SA (THA-2(nd)). Methods: This is a single centre, multi-surgeon, review of prospective data. Thirty-seven patients (47 hips) that had SA and 1 degrees THA(s), formed the cases (26 THA-1(st); 21 THA-2(nd)). Most cases had 1-level SA (n = 24). Controls were patients without SA that had THA, over the same period matched for age, gender and prosthesis type. Outcome measures included complication-, revision- rates, Oxford-Hip- and Harris-Hip-Scores (OHS/HHS) (Delta: difference between pre- and post-operative scores). This is a single-centre, multi-surgeon, review of prospective data. Results: At a mean follow-up of 6 years, more complications were seen in cases of THA and SA compared with controls without SA (7 vs. 2) (p = 0.03). Consequently, more cases were revised (n = 4) compared with controls (n = 0) (p = 0.02). There were no differences in functional outcome between cases and controls (p = 0.1-0.6). No differences in complications- (4/26 vs. 3/21; p = 1.00) or revision- rates (2/26 vs. 2/21; p = 1.00) were seen between THA-1(st) and THA-2(nd) Groups. The THA-1(st) Group had higher pre- and post-operative OHS/HHS, compared to the THA-2(nd) Group. However, no significant difference in Delta OHS (24 vs. 17) and Delta HHS (39 vs. 26) were seen between the THA-1(st) and THA-2(nd) Groups (p = 0.1). Conclusions: Patients with THA and SA, had increased rates of revision; but no differences in patient-reported outcome measures (PROMs) were detected. Addressing the hip pathology first may be associated with improved functional outcome.