Synchronous or sequential cementless bilateral total hip arthroplasty for osseous ankylosed hips with ankylosing spondylitis

Abstract

Background: Bilateral osseous ankylosed hips secondary to ankylosis spondylitis (AS) are relatively rare but impact the quality of life hugely. Cementless total hip arthroplasty (THA) for bilateral osseous ankylosed hips with AS is a challenging procedure. No previous literature compares the clinical outcomes of synchronous and sequential bilateral THA for these special patients. Methods: 23 patients (46 hips) were retrospectively analyzed and divided into bilateral THA synchronously (group A) and sequentially (group B). The clinical measurement, radiological assessments, and complications were compared. Independent sample T test was used for data analysis. Results: Harris Hip Scores (HHS) improved greatly for both groups (P = 0.58) as well as the range of motion (P = 0.64). But group B can realize shorter time (3.6 ± 1.2 days) to walk for the first time postoperatively (P = 0.02). Group A needed more blood transfusions (P = 0.028). For group A, no statistical difference was found in the bilateral inclination of cup (IC) (P = 0.48) and femoral offset (FO) (P = 0.07). For group B, no statistical difference was observed in bilateral IC (P = 0.37) but in bilateral FO (P = 0.04). Group A showed the fewer difference of bilateral IC (P = 0.02), while comparative measurements were found for two groups in the difference of bilateral FO (P = 0.78) and leg length discrepancy (P = 0.83). For both groups, the total hospital expense for each patient was similar and almost all patients were very satisfied with the outcomes. For group A, one patient encountered femoral fracture intraoperatively and another patient encountered hip dislocation and delay union of wound. 3 hips from group A and 3 hips from group B encountered heterotopic ossification. Conclusions: Our retrospective research demonstrated that cementless bilateral THA was a reliable treatment for osseous ankylosed hip due to AS. Synchronous and sequential bilateral THA can realize similarly satisfactory clinical outcomes and radiographic evaluation.