Spinopelvic imbalances are associated with worse postoperative functional outcomes in patients undergoing total hip arthroplasty

Purpose: We aimed to investigate the relationship between spinopelvic imbalances and functional disabilities after total hip arthroplasty in an at least two years of follow-up. Methods: Patients with normal sagittal alignment and normal motion (PI-LL < 10°, APP < 13°, ∆SS > 10°) were defined as control, and patients with any of sagittal alignment or motion abnormalities were defined as case groups. Visual Analog Scale, SF-36, Harris hip score, HOOS-JR, and complications were recorded. Results: The differences of the means of Harris hip score, HOOS-JR, SF-36, and VAS score in the control and case groups were statistically significant. The mean of these parameters in patients with sagittal balanced (PI-LL < 10°) was much better than patients with sagittal unbalanced (PI-LL > 10°). Same results were noted in patients with decreased (∆SS < 10°) and normal spinopelvic motions (∆SS > 10°). Conclusion: Our observations indicate that spinopelvic imbalances are associated with worse postoperative functional outcomes in patients undergoing total hip arthroplasty.