Asymptomatic Gluteal Tendinopathies Negatively Impact Outcomes of Total Hip Arthroplasty: A Propensity-Score Matched Study

Abstract Purpose The purpose of this study was to compare outcomes after total hip arthroplasty (THA) in patients with preoperative asymptomatic gluteus medius and minimus (GMM) pathology to a control group with no GMM pathology. Methods Patients undergoing THA for osteoarthritis (OA) between August 2012 and March 2018 were retrospectively reviewed. Asymptomatic GMM pathology was considered as the presence of gluteal tendinopathy diagnosed by magnetic resonance imaging (MRI) without the following clinical symptoms: Trendelenburg gait or test, abductor weakness, and lateral thigh tenderness. Patients with asymptomatic GMM pathology were matched (1:1) to patients without GMM pathology on MRI. Two-year data were collected on patient reported outcomes including Harris Hip Score (HHS), Forgotten Joint Score (FJS), pain, and satisfaction. Postoperative clinical exam, radiographic measures, complications, and revisions for both groups were reviewed. Results Fifty cases of asymptomatic GMM pathology were successfully matched to 50 hips without GMM pathology on MRI. Patients with asymptomatic GMM pathology demonstrated significantly worse outcomes regarding 2-year HHS (86.24 vs. 92.39, p=0.04), VAS for pain (1.82 vs. 0.98, p=0.05), and patient satisfaction (7.69 vs. 9.16, p=0.002). The study group exhibited significantly higher rates of lateral hip pain postoperatively. Two cases (4%) in the control group underwent a revision THA and four cases (8%) in the study group underwent revision THA. Conclusion In patients undergoing THA for OA, those with asymptomatic GMM pathology experience inferior two-year postoperative PROs compared to a matched group. This finding should raise awareness surrounding this important pathology’s negative impact on surgical outcomes, thus warranting increased vigilance, and possibly justifying concomitant treatment, even in cases of asymptomatic GMM tears. Level of Evidence Level III- Retrospective comparative prognostic study.