Short-term outcomes of open hip preservation surgery for symptomatic extraarticular femoroacetabular impingement.

INTRODUCTION

The purposes of this study were to describe: (i) short-term disease-specific patient-reported outcome scores (PROMs); and (ii) factors associated with reoperation or treatment failure in patients undergoing open hip preservation surgery for symptomatic extraarticular FAI.

METHODS

Patients undergoing open hip preservation surgery for symptomatic extraarticular FAI were identified from a prospective, single-centre hip preservation registry (n = 51 patients; median clinical follow-up 24 [range 11-49] months). Hip-specific PROMs were assessed preoperatively, 6 months, and each year subsequently. Patients undergoing reoperation or treatment failure (<10 point improvement in iHOT-33 postoperatively) over the study period were identified. Preoperative associated factors were explored on a univariate basis.

RESULTS

International Hip Outcome Tool-33 (iHOT-33) improved from 33 (standard deviation [SD] 18) to 62 (26) at most recent follow-up and 76% of patients improved by minimum clinically important difference (MCID). Harris Hip Score improved from 53 (15) to 75 (17) at most recent follow-up and 79% of patients improved by MCID. Hip Outcome Score (HOS) Sport improved from 45 (26) to 66 (28) at most recent follow-up and 60% of patients improved by MCID. Continued improvements in mean follow-up scores were seen from 1 year to 2 years. Overall, 7 patients underwent reoperation and 9 patients failed to improve by MCID. Preoperative HOS Sport was higher in patients experiencing reoperation or treatment failure (58 [SD 19] vs. 40 [SD 27] respectively; p = 0.03). No other associated demographic, physical examination, or radiographic factors were found.

CONCLUSIONS

Open treatment of extraarticular FAI results in short-term improvements in hip-specific PROMs in most patients. Higher HOS Sport scores were associated with reoperation or treatment failure. Longer-term follow-up is necessary to define maximum improvements in this challenging patient population.