Defining the Maximum Outcome Improvement of the Modified Harris Hip Score, the Nonarthritic Hip Score, the Visual Analog Scale For Pain, and the International Hip Outcome Tool-12 in the Arthroscopic Management for Femoroacetabular Impingement Syndrome and Labral Tear
Purpose: To determine the respective percent thresholds for achieving the maximal outcome improvement (MOI) for the modified Harris Hip Score (mHHS), the Nonarthritic Hip Score (NAHS), the visual analog scale (VAS) for pain, and the International Hip Outcome Tool-12 (iHOT-12) that were associated with satisfaction following hip arthroscopy for femoroacetabular impingement syndrome and labral tear, and to identify preoperative predictors of reaching the mHHS, NAHS, VAS, and the iHOT-12 thresholds for achieving the MOI.
Methods: An anchor question was provided to patients who underwent hip arthroscopy between April 2008 and April 2019. Patients were included if they answered the anchor question and had minimum 1-year follow-up. Patients were excluded if they had a previous ipsilateral hip surgery, a Tönnis grade >1, hip dysplasia, or a previous hip condition. Receiver operating characteristic analysis was used to determine the thresholds for the percentage of the MOI predictive of satisfaction. Multivariate logistic regression was used to determine predictors of achieving the MOI threshold.
Results: In total, 407 hips (375 patients) were included, with 279 female patients (68.6%). The average age, body mass index, and follow-up time were 38.8 ± 13.7 years, 26.6 ± 5.8, and 51.8 ± 33.2 months, respectively. Satisfaction with the current state of their hip was reported in 77.9% (317) of the cases. It was determined that 54.8%, 52.5%, 55.5%, and 55.8% of MOI were the thresholds for maximal predictability of satisfaction for mHHS, NAHS, VAS, and iHOT-12, respectively. Predictors of achieving MOI were not identified.
Conclusions: Following hip arthroscopy in the context of femoroacetabular impingement syndrome and labral tear, the thresholds for achieving the MOI for the mHHS, NAHS, VAS for pain, and iHOT-12 were 54.8%, 52.5%, 55.5%, and 55.8% respectively. No preoperative predictors of achieving the MOI were identified.
Level of evidence: IV, case-series.