Older age and smaller joint space width are associated with conversion to total hip arthroplasty following hip arthroscopy.

Purpose: The goal of this study was to define the outcomes of patients following hip arthroscopy and to identify potential factors, found during hip arthroscopy, that were associated with patients' eventual conversion to total hip arthroplasty (THA). Methods: Patients who had undergone hip arthroscopy from January 2010 to January 2015 were retrospectively reviewed and patients were reported if they had a THA in the same hip. Patients were followed up to December 2022 resulting in between 7 and 12 years of follow-up. Measures from the hip scope including joint space width and cartilage grades were reported. Differences in these measures and demographics were compared between patients who had THA after hip arthroscopy and those who did not with T-tests. Results: Patients who had hip arthroscopy and were then converted to THA were significantly older than those patients who did not have THA (50.3 vs 42.0 years) (p = 0.039). The average time of conversion to THA from index hip arthroscopy was 3.59 years with a range of 0.48-8.91 years. Joint space width in patients converted to THA was significantly less, 3.08 mm ± 1.93 mm, compared to non-THA converted patients, 3.62 mm ± 0.88 mm (p < 0.001). Conclusions: Older age and smaller joint space width of the hip was associated with patients who were converted to THA following hip arthroscopy. Level of evidence: Level III.