OP2.6 Periacetabular Osteotomy and Combined Femoral Head-Neck Junction Osteochondroplasty: A Concise Follow-up of a Previous Report at a mean of 10 years

Background: Hip dysplasia is a well-known cause of hip dysfunction and secondary osteoarthritis in the young adult population that is commonly treated by periacetabular osteotomy (PAO). Contemporary treatment for hip dysplasia includes PAO with selected concomitant procedures including osteochondroplasty (OCP) for femoral head-neck abnormalities to improve survivorship and clinical outcomes following the PAO. The purpose of this study is to assess the 10-year survivorship and outcomes following PAO with or without OCP.

Methods: This is a retrospective review of 38 patients (38 hips) who underwent a PAO with OCP compared to a matched control group of 42 patients (42 hips) who underwent a PAO alone between 2000 and 2007. The modified Harris hip score (mHHS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were utilized for outcome measurements. Failure was defined as clinical failure (failure to meet mHHS MCID or PASS), conversion to THA, reoperations, and composite failure (either clinical failure or reoperation).

Results: Mean follow up was 10.6 years for the PAO OCP cohort (range, 6.9 to 16.3 years) and 11.8 years for the PAO-only cohort (range, 7.2-17.2 years). Improvement in PROMs were similar between groups along with MCID, PASS, and rates of clinical failure (p-values >0.05). Rates of reoperation/complications were higher in the PAO only group (33%) compared to the PAO/osteoplasty group (8%) (p=0.005). Four of the reoperations in the PAO only group were from secondary FAI and included OCP and labral repair. Rates of THA conversion slightly missed significance between the groups with 14% in the PAO only and 3% in the PAO/osteo group (p=0.07). Kaplan-Meier (KM) 10-year survivorship estimates from clinical failure were 93.8% and 89.2% for the PAO/osteo and PAO only groups, respectively. The KM 10-year survivorship estimates from reoperation were 97.4% and 72.9%, respectively. Finally, the KM 10-year survivorship estimates from composite failure were 93.8% and 89.7%, respectively.

Conclusions: At ten years follow-up, patients undergoing PAO/osteo versus PAO alone, had similar improvements in PROs. However, there was a higher rate of reoperation among patients that underwent PAO alone. Future, long-term follow-up studies should continue to investigate the effect of OCP on outcomes.