Arthroscopic Fractional lengthening After THA Results in Improved PROs and Low Rates of Revision THA

Purpose To report the clinical outcomes and reoperation rates of arthro- and endo-scopic iliopsoas release at short-term follow-up following ipsilateral total hip arthroplasty from two separate medical institutions, and to evaluate whether demographic and radiographic parameters are associated with postoperative patient reported outcomes. Methods Patients with iliopsoas tendinitis in the setting of prior THA that underwent arthroscopic iliopsoas fractional lengthening from 1988 – 2023 at two academic institutions were reviewed. Patients were included if they had 12 months of follow-up and evaluated for preoperative anterior acetabular component overhang, surgery satisfaction, postoperative subjective hip flexion strength and anterior groin pain improvement, modified Harris Hip Score (mHHS), Single Assessment Numeric Evaluation (SANE) score, Tegner activity scale, visual analog scale (VAS), and revision hip arthroplasty. Results Sixty hips in 58 patients (19 males, 39 females) were followed for a mean of 39.3 (12.0-105.9) months postoperatively. 77% of patients reported feeling “much” or “slightly better”, 75% reported improved anterior groin pain, and 60% reported improved subjective hip flexion strength. Surgery satisfaction was 7.2 ± 3.3 (scale of 0 to 10). Mean postoperative mHHS, VAS pain at rest, VAS pain with use, and SANE scores were 73.9 ± 19.4, 1.3 ± 2.4, 3.8 ± 2.9, and 71.9 ± 21.9 respectively. Preoperative anterior acetabular component overhang was 3.3 ± 6.5 mm and didn’t significantly correlate with postoperative PROs (p ≥ 0.45). Tegner score improved to 2.9 ± 1.4 from 2.5 ± 1.7 preoperatively (p = 0.0253). Three patients underwent revision arthroplasty at a mean of 25.3 (11.6 – 40.4) months postoperatively, with an acetabular component revision rate of 3.3%. Conclusions Satisfactory outcomes and low revision arthroplasty rates were observed in patients undergoing arthroscopic iliopsoas lengthening following THA. There was no statistically significant relationship between anterior acetabular component overhang and final PROs.