Association Between Native Hip Distraction and Preoperative Patient-Reported Outcomes in Nondysplastic Female Patients Undergoing Primary Hip Arthroscopy

Background: Hip instability is a common driver of pain and dysfunction in those undergoing hip arthroscopy. While an axial traction examination is thought to correlate well with overall joint stability, the relationship between patient-reported outcomes (PROs) and intraoperative distractibility has not been quantified. Hypothesis/Purpose: The purpose of this study was to determine whether a relationship exists between ease of intraoperative traction and overall hip function. It was hypothesized that those who axially distract greater distances would have lower preoperative hip function. Study Design: Case series; Level of evidence, 4. Methods: All nondysplastic female patients ≥18 years who underwent a primary hip arthroscopy surgery with completed traction data were placed into tertiles (T) (with T1 being the least and T3 the most) according to their total distraction distance, defined as the difference between the joint space at 0 and 100 pounds of force. Preoperative Patient-Reported Outcome Measurement Information System-Physical Function Version 2.0 scores, Modified Hip Harris Scores (MHHS), patient perceived function (Single Assessment Numeric Evaluation [SANE]) scores, and pain at rest, pain with activities of daily living (ADL), and pain with sports on a scale from 0 to 10 were reviewed. Significant differences were determined by 1-way analysis of variance and regression analyses. Results: A total of 114 patients were included, with 38 patients in each tertile. Patients in the T1 group had significantly higher preoperative PROs on MHHS (63.9 ± 17.7 vs 52.3 ± 16.1; P = .013) and SANE scores (63.8 ± 15.5 vs 46.1 ± 18.5; P < .001) compared with patients in the T3 group. Moreover, linear regression controlling for age, body mass index, lateral center edge angle, and alpha angle showed a significant inverse relationship between native hip distractibility and MHHS (β = −2.66 [95% CI, −4.37 to −0.940]; P = .003) and SANE scores (β = −3.50 [95% CI, −5.21 to −1.79]; P < .001), and a direct relationship with distraction distance and increased pain with ADL (β = 0.285 [95% CI, 0.093 to 0.477]; P = .004). Conclusion: Increased native hip distractibility on an intraoperative traction examination before capsular violation in nondysplastic female patients undergoing primary hip arthroscopy is associated with lower PROs. Future studies are needed to determine whether there is an association between increased time-zero postoperative distraction distance after hip arthroscopy and long-term PROs.