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 2 ) and followed for 10.0 ± 6.9 months postoperatively (range: 4‐25 months). Patients experienced significant ( P < .001) postoperative improvements in the Visual Analog Scale at rest (1.4 ± 2.2 vs 2.8 ± 2.1), Visual Analog Scale with use (3.0 ± 2.9 vs 7.8 ± 1.8), Tegner activity scale (2.8 ± 1.2 vs 2.0 ± 1.0), and Single Assessment Numeric Evaluation score (73.8 ± 22.5 vs 47.7 ± 22.2). Postoperative surgical satisfaction was 8.0 ± 2.7 (scale: 0‐10). Nearly 90% of patients reported feeling much or slightly better regarding their anterior groin pain postoperatively at 2‐week (91%), 6‐week (88%), 3‐month (91%), and final follow‐up (92%). Regarding hip flexion strength, ≥66% reported feeling much or slightly better at 2‐week (73%), 6‐week (95%), 3‐month (89%), and final follow‐up (66%). Three hips (6%) underwent reoperation at the final follow‐up (1 acetabular screw removal with open revision release, 1 revision total hip arthroplasty for loosening, and 1 two‐stage exchange for nonacute periprosthetic joint infection). 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.