Summary

The purpose of this study is to report minimum 2-year follow-up patient-reported outcome scores (PROs) and rates of achieving the minimal clinically important difference (MCID), the patient acceptable symptomatic state (PASS), and the maximal outcome improvement (MOI) on adolescents following primary hip arthroscopy for femoroacetabular impingement syndrome (FAIS).

Abstract

Purpose

To report minimum 2-year follow-up patient-reported outcome scores (PROs) and rates of achieving the minimal clinically important difference (MCID), the patient acceptable symptomatic state (PASS), and the maximal outcome improvement (MOI) on adolescents following primary hip arthroscopy for femoroacetabular impingement syndrome (FAIS). Secondly, to determine risk factors for revision surgery.

Methods

Prospectively collected data from two high-volume hip arthroscopy centers were retrospectively reviewed on adolescents (= 19 years old) who underwent primary hip arthroscopy between November 2008 and February 2019. Adolescents with a minimum 2-year follow-up for the modified Harris Hip Score (mHHS), Non-Arthritic Hip Score (NAHS), Hip Outcome Score-Sports Specific Subscale (HOS-SSS), International Hip Outcome Tool-12 (iHOT-12), and visual analog scale (VAS) for pain were included regardless of their growth plate status. Exclusion criteria were Tönnis grade > 1, lateral center edge-angle < 18º, previous ipsilateral hip surgery or conditions. Pre and postoperative radiographic data, MCID, PASS, MOI, secondary surgeries and complications were reported. A multivariable survival analysis for risk factors for secondary surgery was conducted.

Results

A total of 287 hips (249 patients) were included (74.9% females). The mean values for age, body mass index, and follow-up were 16.3±1.3 years, 22.3±3.5, and 26.6±9.4 months respectively. Further, 88.9% underwent labral repair, 81.5% femoroplasty, and 85.4% capsular closure. Improvement for all PROs was reported (P < 0.001) with high patient satisfaction (8.8 ± 1.5). Achievement for the MCID was 71.7%, 83.0%, 68.1%, and 79.5% for the mHHS, NAHS, HOS-SSS, and iHOT-12 respectively. Achievement for the PASS was 68.3% for the mHHS and 73.2% for the NAHS. The MOI for mHHS, NAHS, and VAS was 58.3%, 77.0%, and 59.6% respectively. Rates of revision hip arthroscopy, cam recurrence and heterotopic ossification were 5.8%, 1.7%, and 5.5% respectively. Acetabular retroversion was found to be a risk factor for revision surgery (P = 0.03).

Conclusion

The results of this multi-center study demonstrated that adolescents who underwent primary hip arthroscopy for FAIS reported significant improvement in all PROs, with satisfactory achievement rates for the MCID, PASS, MOI, and high patient satisfaction at a minimum 2-year follow-up.

Level of Evidence: IV; Retrospective Multi-center Study.