EP1.67 Decision-Making Strategies for Simultaneous Versus Staged Hip Arthroscopy and Periacetabular Osteotomy for Adults With Acetabular Dysplasia: A Systematic Review

Abstract Background Acetabular dysplasia in adults is commonly managed with periacetabular osteotomy (PAO) and adjunctive hip arthroscopy (HA) to address intra-articular pathology. However, substantial variability exists in surgical strategy, including the use of simultaneous versus staged procedures, sequencing, and timing. Current evidence is heterogeneous and lacks robust comparative data. This study aimed to synthesize available evidence to inform a clinically relevant decision-making framework for the use and timing of HA in patients undergoing PAO. Methods A systematic review was performed using MEDLINE (Ovid), Embase, Scopus, and CENTRAL from inception to March 7, 2026. Studies evaluating clinical or radiographic outcomes of staged or simultaneous HA and PAO in patients with hip dysplasia were included. Data were synthesized qualitatively, and patterns in surgical decision-making were used to develop a data-informed clinical framework. Risk of bias was assessed using ROBINS-I for comparative non-randomized studies and JBI for case series. Results Of the 491 records identified, 21 studies (33,164 patients) met the inclusion criteria. . Patients were young (mean age 26.7 years) and predominantly female (66.7%), with a median follow-up of 34 months (range 20–154). Simultaneous HA + PAO was the dominant strategy (17/21), while staged approaches (4/21) were typically reserved for diagnostic uncertainty or variable intra-articular pathology. Across all included studies, median THA conversion was 0.6% (range 0–20%), with most studies reporting 0–3%. Patient-reported outcomes improved consistently (mHHS approximately +25, iHOT approximately +45 and NAHS approximately +27). Complication rates ranged from 4–37.5%, clustering between 8–15%, while reoperation rates were typically 2–11%. Indications for arthroscopy and criteria guiding sequencing were inconsistently reported. Conclusion Combined PAO and HA produces favourable short- to mid-term outcomes, but decision-making regarding timing and sequencing remains poorly defined. We propose a framework stratified by the certainty of intra-articular pathology and suspected cartilage status: simultaneous HA may be preferred when intra-articular pathology is clearly defined preoperatively, while a staged approach may be considered in diagnostic uncertainty or suspected advanced chondral damage. This framework offers a structured approach to surgical planning but remains hypothesis generating and requires validation in comparative studies.