FP8.2 Activity Level Maintenance at 10-Year Minimum Follow-up Among Active Patients Undergoing Periacetabular Osteotomy

Background: Periacetabular osteotomy (PAO) can treat pain, dysfunction, and decreased activity secondary to hip dysplasia. Patients’ preoperative and postoperative activity can be measured using the University of California Los Angeles (UCLA) Activity Score, a validated questionnaire. Understanding return to and maintenance of high activity at long-term follow-up after PAO is a priority for active patients.

Purpose: To provide long-term follow-up of a previously published cohort that will help examine maintenance of activity after PAO, guide future treatment decision making, and inform patient counseling.

Methods: This is a prospective, longitudinal cohort of patients undergoing PAO between 2006 and 2013. Inclusion criteria included LCEA <25°, highly active individuals (UCLA score ≥7), and 10-year minimum follow-up. UCLA, modified Harris Hip Score (mHHS), and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were obtained, along with demographic information. UCLA score ≥7 was defined as high activity. P-values <0.05 were considered significant.

Results: The cohort included 68 hips (61 patients) with 7 (10.3%) undergoing additional surgery (4 total hip arthroplasty, 3 osteochondroplasty) at a mean of 9.8 (6.0-15.8) years. The remaining 61 hips (54 patients) were analyzed. Mean age at PAO was 24.7 years (14.7-44.8) with female predominance (72.1%). Mean follow-up was 12.5 years (10.2-17.1). 54/61 (88.5%) hips either maintained high activity with UCLA >7 (43/61, 70.5%) or reported lower activity unrelated to their surgical hip (11/61, 18.0%). Mean UCLA score decreased from 8.9 to 8.1 (P=0.009), mHHS improved from 64.6 to 88.8 (P <0.001) with 49/61 hips (80.3%) achieving MCID, and WOMAC pain score improved from 68.2 to 89.0 (P<0.001) with 35/51 hips (68.7%) achieving MCID. Hips with PAO before age 25 were more likely to be in higher activity groups at follow-up (P=0.030).

Conclusion: Patients with hip dysplasia can be treated with PAO to help maintain activity levels and preserve their native hip. At long-term follow-up (mean 12.5 years), 54/68 (79.4%) hips did not have additional surgeries and either remained in the high activity group or reported a lower activity level unrelated to their PAO hip. PAO appears to be a durable hip preservation technique at 12.5 years follow-up for highly active patients.