Comparable Clinical Outcomes of Hip Arthroscopy for Femoroacetabular Impingement Syndrome in Patients with Fibromyalgia: A Propensity-Matched Study with a Mean 2-Year Follow-Up.

Objective: To evaluate patient-reported outcomes (PROs), achievement of clinically significant outcomes (CSOs), and reoperation-free survivorship at short-term follow-up after hip arthroscopy (HA) for femoroacetabular impingement syndrome (FAIS) in patients with and without fibromyalgia (FM).

Methods: A prospective repository was retrospectively reviewed to identify patients undergoing primary HA for FAIS between 1/2012-7/2019 with 2-year follow-up. Exclusions included revisions, staged/concomitant procedures, congenital hip disorders, secondary hip pathology, or missing 2-year follow-up. FM patients were propensity-matched 1:2 controlling for age, sex, and body-mass-index with non-FM patients. PROs included Hip Outcome Score-Activities of Daily Living (HOS-ADL) and Sports Subscale (HOS-SS), 12-item International Hip Outcome Tool (iHOT-12), modified Harris Hip Score (mHHS), and Visual Analog Scale (VAS) for Pain and Satisfaction. Cohort-specific minimal clinically important difference (MCID) and patient acceptable symptom state (PASS) thresholds were calculated and compared. Reoperation rates were compared.

Results: Overall, 33 hips in 30 FM patients were matched to 66 hips in 66 non-FM patients. Demographics were similar between FM (age: 37.03±12.1 years; 93.9% female; BMI: 27.04±6.7 kg/m2) and non-FM patients (age: 38.85±14.0 years; 92.4% female; BMI: 26.80±5.5 kg/m2). Average follow-up was 26.6 months. At 2 years, FM patients had inferior HOS-SS (P=0.01), mHHS (P=0.009), iHOT-12 (P=0.038), and VAS-Pain scores (P=0.003). However, achievement of MCID ≥ 1 PRO (P=1.00) and PASS ≥ 1 PRO (P=0.15) at 2-year follow-up was similar between groups. FM patients demonstrated inferior achievement of MCID for VAS-Pain and PASS for mHHS and VAS-Pain. Reoperation-free survivorship was comparable (P=0.48).

Conclusions: Patients undergoing primary HA for FAIS with FM achieve statistically significant inferior PROs but demonstrate relatively comparable CSOs to patients without FM at 2-year follow-up, with the exception of mHHS for MCID and VAS-Pain for MCID and PASS. FM patients demonstrate similar reoperation-free survivorship compared non-FM at 2-year follow-up. Methods: Retrospective, Matched Case-Control Study, Level III.