Clinical Outcomes After Hip Arthroscopy for Patients With Rheumatoid Arthritis: A Matched-Pair Control Study With Minimum 2-Year Follow-Up.

Purpose: This study analyzed minimum 2-year hip arthroscopy outcomes in rheumatoid arthritis (RA) patients and non-RA control patients. It also examined whether disease-modifying antirheumatic drugs (DMARDs) affected RA patient outcomes. We hypothesized that patients with RA undergoing hip arthroscopy would have lower reported outcome scores.

Methods: Data were prospectively collected on all hip arthroscopies performed from 2009-2013. The indications for surgery were patients with hip pain and with physical examination and imaging studies confirming intra-articular pathology in whom conservative management had failed. The exclusion criteria were previous ipsilateral hip conditions and Tönnis grade greater than 1. Patients with at least 2 years of follow-up and preoperative RA diagnoses were matched (1:2 ratio) to controls without RA (based on age ± 5 years, body mass index ± 5, and lateral center-edge angle [18°-25°, 26°-39°, or >39°]). RA cases were further analyzed based on DMARD use. Patient-reported outcome (PRO) scores were collected preoperatively and postoperatively at 3 months, as well as annually thereafter. The outcomes collected included the modified Harris Hip Score, Non-Arthritic Hip Score, Hip Outcome Score-Sports Specific Subscale, visual analog scale (VAS) score for pain, satisfaction rating, future procedures, and complications.

Results: We matched 26 hips in 20 RA patients to a control group of 52 hips in 52 patients. At a minimum of 2 years of follow-up, RA patients reported no significant improvements except in the Non-Arthritic Hip Score, whereas the control group significantly improved in all PRO and VAS scores. Preoperative PRO and VAS scores between the RA and control groups were not significantly different, but postoperatively, all scores were lower in RA patients at a minimum of 2 years, whether they were taking DMARDs or not. Patients taking DMARDs showed slightly more improvement in PRO and VAS scores. There was a greater trend toward more secondary arthroscopy procedures for RA patients (19.2% vs 7.7%, P = .47), but total hip arthroplasty rates were similar. Complication rates were low in both groups.

Conclusions: Patients undergoing hip arthroscopy who have a diagnosis of RA had less improvement in PRO and VAS scores and were less satisfied than a matched control group of patients without RA at a minimum 2-year follow-up. Patients who were taking DMARDs had slightly better improvement in their PRO and VAS scores than nonmedicated patients. With this early follow-up, we could not show a difference in the rate of conversion to total hip arthroplasty, although RA patients required more revision arthroscopies than controls. Patients with a diagnosis of RA who undergo hip arthroscopy should be counseled about the potential for lesser degrees of postoperative improvement and should have their expectations managed accordingly. LEVEL OF EVIDENCE: Level III, comparative trial.