Association Between Global Overcoverage and Long-term Survivorship,Chondrolabral Junction Breakdown,and Reduced Joint Space Width: Minimum 8-Year Follow-up

Abstract

Background:

Although previous literature has established the association between femoroacetabular impingement and progressive hip osteoarthritis, there exists a paucity of studies investigating the effects of global acetabular overcoverage on chondral wear and long-term outcomes.

Purpose:

To compare baseline joint space width (JSW), intraoperative findings, long-term total hip arthroplasty (THA)–free survivorship, patient-reported outcome measures (PROMs), pain levels, and patient satisfaction in patients who underwent hip arthroscopy with global overcoverage (GO) to a matched-control (MC) cohort.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

In this retrospective analysis, the authors queried patients who underwent hip arthroscopy for acetabular labral tears secondary to femoroacetabular impingement. Patients with complete PROMs at a minimum 8-year follow-up, the presence of coxa profunda as indicated by an acetabular wall projecting medial to the ilioischial line, and a lateral center-edge angle >40° were matched 1:1 by sex, age, body mass index, Tönnis grade, and labral treatment to a MC cohort of patients who had normal acetabular coverage. Baseline radiographic and intraoperative findings were compared between cohorts. Collected outcomes include the modified Harris Hip Score, Nonarthritic Hip Score, Lower Extremity Functional Scale score, Hip Outcome Score–Activities of Daily Living, Hip Outcome Score–Sports Specific Subscale, 33-item International Hip Outcome Tool score, pain levels, patient satisfaction, and conversion to THA.

Results:

In total, 38 patients with GO were 1:1 matched to a MC cohort. The GO cohort had significantly decreased baseline JSW at 50° (P = .002) and greater chondrolabral junction breakdown (P = .037). The GO and MC cohorts achieved similar outcomes for all 6 PROMs, rates of conversion to THA, pain levels, and patient satisfaction. Kaplan-Meier survival analysis demonstrated that the patients experienced a similar overall 18-year THA-free survival rate (GO: 71.1% vs MC: 84.2%; P = .101). To isolate the long-term effects of GO on hip arthroscopy outcomes, 6- to 18-year THA-free survivorship was examined, revealing that the GO cohort (−13.1%) experienced a significantly greater decrease compared with the MC cohort (−5.3%) (P = .008).

Conclusion:

Patients with GO had significantly lower baseline ipsilateral JSW at 50° and greater intraoperative severity of chondrolabral junction breakdown. Furthermore, the GO cohort experienced a significantly greater decrease in long-term THA-free survivorship 6 to 18 years after hip arthroscopy.