Hip Arthroscopy Patients with Concomitant Low Back Pain Show Clinical Improvement and Time-Dependent Survivorship Comparable to Those Without Low Back Pain: A Propensity Matched Study at Long-Term Follow-Up.

Abstract

Purpose: The purpose of this study was to evaluate patient-reported outcomes (PROs), achievement of clinically significant outcomes (CSOs), and reoperation-free survivorship at long-term follow-up following primary hip arthroscopy (HA) for femoroacetabular impingement syndrome (FAIS) in patients with and without preoperative lower back pain (LBP).

Methods: A repository was reviewed to identify patients who underwent primary HA for FAIS between 1/2012-5/2014 with 10-year follow-up. Exclusion criteria included prior ipsilateral hip surgery, concomitant procedures, congenital hip disorders, non-FAIS hip pathologies, Tönnis grade >1, history of platelet-rich plasma injections, and missing 10-year follow-up. Patients that self-reported preoperative, concomitant LBP were propensity-matched 1:1 to non-LBP patients by age, sex, and body-mass-index (BMI). PROs collected included Hip Outcome Score-Activities of Daily Living and Sports Subscale (HOS-ADL/HOS-SS), 12-item International Hip Outcome Tool (iHOT-12), modified Harris Hip Score (mHHS), and Visual Analog Scale (VAS) for Pain and Satisfaction. Minimal clinically important difference (MCID) and patient acceptable symptom state (PASS) were compared. Subgroup analysis was conducted comparing females and males with LBP. Reoperation-free survivorship was compared with Kaplan-Meier analysis. An a priori power analysis determined sample size.

Results: Overall, 69 hips in 67 LBP patients were matched to 69 hips in 67 non-LBP patients. Demographics were similar between groups, including age (39.22±10.3 vs. 38.99±10.7 years, P=0.90), sex (55.1% vs. 55.1% female, P=1.0), and BMI (26.15±4.6 vs. 26.36±5.1 kg/m², P=0.80). Average follow-up duration was 10.43±0.4 years. The most common cause of LBP was degenerative lumbar or sacral conditions, including degenerative disc disease (DDD), degenerative joint disease (DJD), or spondylosis, accounting for 38.8% (26/69) of the cohort. Mean preoperative HOS-ADL (62.38±18.7 vs. 64.45±21.1, P=0.57), HOS-SS (37.83±22.6 vs. 45.67±24.7, P=0.09), mHHS (53.63±14.6 vs. 57.01±14.6, P=0.22), iHOT-12 (33.29±19.0 vs. 39.49±15.8, P=0.27), and VAS Pain (71.88±18.3 vs. 71.87±19.1, P=1.0) were similar between LBP and non-LBP patients. Additionally, the mean 10-year follow-up HOS-ADL (81.48±21.2 vs. 79.57±22.0, P=0.66), HOS-SS (66.87±31.3 vs. 67.36±30.4, P=0.94), mHHS (74.15±18.8 vs. 73.19±17.7, P=0.79), iHOT-12 (77.77±23.3 vs. 69.63±29.3, P=0.13), VAS Pain (23.98±25.0 vs. 32.19±28.4, P=0.11), and VAS Satisfaction (83.47±25.3 vs. 81.43±29.7, P=0.73) were similar between LBP and non-LBP patients. LBP and non-LBP patients had comparable MCID achievement for HOS-ADL (72% vs. 56%, P=0.13), HOS-SS (74% vs. 50%, P=0.06), mHHS (74% vs. 65%, P=0.47), iHOT-12 (83% vs. 72%, P=0.67), VAS Pain (89% vs. 75%, P=0.10), and any PRO (98% vs. 93%, P=0.32). Similarly, LBP and non-LBP patients had comparable PASS achievement for HOS-ADL (64% vs. 65%, P=1.0), HOS-SS (66% vs. 69%, P=0.83), mHHS (64% vs. 60%, P=0.84), iHOT-12 (65% vs 61%, P=0.84), VAS Pain (55% vs. 50%, P=0.71), and any PRO (76% vs. 80%, P=0.81). Subgroup analysis revealed no significant differences between females and males with LBP in preoperative or 10-year follow-up PROs as well as MCID and PASS achievement rates. Reoperation-free survivorship was comparable (P=1.0).

Conclusions: Patients undergoing primary HA for FAIS with concomitant LBP may achieve comparable PROs, CSOs, and reoperation-free time-dependent survivorship to patients without LBP at long-term follow-up.

Level of evidence: Retrospective, Matched Case-Control Study, Level III.