How much arthritis is too much for hip arthroscopy: a systematic review.

PURPOSE The purpose of this study was to determine the extent of preoperative osteoarthritis (OA) that precludes benefit from hip arthroscopy by systematically reviewing the literature on hip arthroscopy in the setting of OA. METHODS We searched the Medline and PubMed databases using the following Medical Subject Heading terms: arthritis, osteoarthritis, chondral damage, chondral injury, chondral delamination, and hip arthroscopy. Two authors independently reviewed the literature and included articles if they were in the English language; commented on preoperative factors, parameters, physical examination, or diagnostic testing that may be evidence of cartilage damage and/or arthritis; contained outcome data on patients undergoing hip arthroscopy; and had a sample size of at least 10 patients with arthritic changes in the hip. We excluded review articles, technique articles, articles with overlapping patient populations, articles with hip arthroscopy used as an adjunct to an open procedure, articles with inflammatory and septic arthritis, and articles with a mean age younger than 18 years. RESULTS Our search identified 518 articles, of which 15 met the inclusion and exclusion criteria. Two thousand fifty-one hips underwent arthroscopy at a mean patient age of 40.2 years. Of these, 1,195 hips had signs of OA. There were 345 conversions to total hip arthroplasty/surface replacement arthroplasty. Of these patients, 274 had OA. Eight patient-reported outcome instruments were used. Factors influencing outcomes were preoperative OA, age, chondral damage, femoroacetabular impingement, and duration of symptoms. CONCLUSIONS Current evidence is insufficient to define a cutoff for how much arthritis is too much for hip arthroscopy. However, this analysis shows that patients with a Tönnis grade of 1 or greater or a joint space of 2 mm or less are less likely to benefit from hip arthroscopy and more likely to require conversion to total hip arthroplasty/surface replacement arthroplasty. Postoperative scores on patient-reported outcome instruments are lower in the arthritic population at follow-up compared with their nonarthritic counterparts. LEVEL OF EVIDENCE Level IV, systematic review of Level III and IV studies.