ePoster #1217 - ISHA Annual Scientific Meeting 2016

What Factors Affect Outcome At 2-5 Years Following Hip Arthroscopy?

Maureen Dwyer, PhD, ATC, Newton, MA UNITED STATES
Jo Ann Lee, NP, Newton, MA UNITED STATES
Joseph C. McCarthy, MD, NEWTON, MA UNITED STATES

Newton Wellesley Hospital, Newton, MA, UNITED STATES

FDA Status Not Applicable

Summary: Our findings demonstrate that, in the presence of all other factors, only patient age and revision procedure affected IHOT-33 scores at 2-5 years following hip arthroscopy.

Abstract:
Objectives Assessing patient-reported outcomes after hip arthroscopy is essential to determining the success of the procedure to the patient. While many studies have reported outcomes over time for this patient population, no study has assessed the effect of potential confounding factors on outcomes in a comprehensive fashion. We examined the relationship between patient, clinical, and surgical factors and total score on the IHOT-33 in patients who had undergone hip arthroscopy 2-5 years prior to evaluation. Methods Patients who had undergone arthroscopic treatment for labrochondral injuries between 2-5 years prior to evaluation were contacted to participate in this study. Clinical outcomes were assessed using the IHOT-33. Data for the following variables were obtained through review of clinical and surgical notes for each patient: sex, age (<40 years, = 40 years), dysplasia (DYS), primary or revision procedure, number of hips involved (1 vs. 2)(HIPS), joint space narrowing on pre-surgical x-ray (XRAY), history of low back pain (LBP), severe chondral damage at time of arthroscopy (SEV), and chondral damage in more than one region at time of arthroscopy (GLOBAL). Patients were grouped based on each binary variable, and total score on the IHOT-33 (TOTAL) was compared for each variable using separate independent samples t-tests (P < 0.05). A multiple linear regression analysis was conducted to examine a relationship between TOTAL and those variables for which univariate analyses demonstrated significant differences. Results Out of 154 patients contacted, completed IHOT-33 data was available for 80 patients (27 males, 53 females), with an average age of 39.3±12.5 years and average alpha angle of 44.3±9.5. Decreases in TOTAL were observed for revision (vs. primary) (53.3±29.5 vs. 69.7±23.8;p=0.037), age <40 (vs. age >40) (60.3±27.7 vs. 74.2±20.5;p=0.13), 2 hips (vs. 1 hip) (57.5±27.6 vs. 70.3±23.9;p=0.05), and female (vs. male) (63.4±26.3 vs. 74.8±21.4;p=0.05). No differences existed between groups for DYS (p=0.53), XRAY (p=0.44), SEV (p=0.88), GLOBAL (p=0.24), or LBP (p=0.87). Multiple regression analysis revealed that revision (p=0.047) and age (p=0.017) made significant contributions to TOTAL independent of HIPS and sex. For patients undergoing revision procedures, the predicted score at 2-5 year follow-up would be 15 points lower than for primary procedure, and, for patients <40 years, the predicted score would be 13 points lower than for patients >40 years. The effect of age based on revision status revealed that, for patients who were <40 years undergoing a revision, the predicted score would be 30 points lower than for patients who were >40 years undergoing a revision. Conclusions Our findings demonstrate that, in the presence of all other factors, only patient age and revision procedure affected IHOT-33 scores at 2-5 years following hip arthroscopy. We observed reduced outcome scores for patients who were younger compared to older patients, with greater reductions present for revision procedures. The reduced scores for younger patients in our study may reveal unmet expectations compared to older patients and a greater impact of revision on outcome. The predicted reductions in IHOT-33 score can be used to provide guidance to patients on realistic expectations following hip arthroscopy.