Significant Clinical Improvements Following Arthroscopic Iliopsoas Fractional Lengthening After Total Hip Arthroplasty: A Prospective Multicenter Study.

Purpose: To prospectively investigate subjective anterior groin pain, patient-reported outcome measures, complications, reoperation rates, and hip flexion strength after arthroscopic iliopsoas fractional lengthening. Methods: From 2023 to 2025, patients with persistent groin pain after total hip arthroplasty refractory to conservative management undergoing arthroscopic iliopsoas fractional lengthening were prospectively identified at 2 tertiary referral centers. Pre- and postoperative outcomes at a minimum 6-month follow-up including the Visual Analog Scale, Tegner activity scale, Single Assessment Numeric Evaluation, and subjective anterior groin pain and hip flexion strength were analyzed. Results: Fifty-nine hips in 56 patients were included (age: 64.9 ± 9.8 years, 59% women, body mass index: 30.0 ± 5.8 kg/m Conclusions: Nearly 90% of patients who underwent arthroscopic iliopsoas fractional lengthening after primary total hip arthroplasty reported improved anterior groin pain, whereas two-thirds reported increased subjective hip flexion strength throughout the follow-up. Of note, clinically meaningful improvement in pain at rest was achieved by 50% of patients based on cohort-specific minimal clinically important difference criteria. Level of Evidence: Level IV, retrospective therapeutic case series.