Poster 214: The Effect of Femoral Retroversion on Hip Range of Motion – A 3D Computational Analysis

Objectives: A subset of patients undergoing hip arthroscopy suffers from persistent pain and dysfunction which can be secondary to a number factors. Femoral rotational deformities are often overlooked and/or providers unsure when address femoral deformities. Currently, there is limited no data guiding surgeons consider osteotomy at the time for FAI. Through previously validated computer-assisted 3D modeling software, this study sought answer two questions: 1) How much retroversion too render cam femoroplasty ineffective in improving range motion (ROM)? 2) In setting an osteotomy, what degree version correction would sufficient improve impingement free ROM? Methods: Ten were selected with symptomatic focal lesions who underwent had pre- post-operative computed tomography (CT) scans. These screened normal acetabular morphology demonstrated radiographic signs osteoarthritis. Pre- involved was performed subsequently dynamized set (15, 5, -5 -15 degrees) define ROM location maximum flexion internal rotation (IR) 90 degrees flexion. Results: Mean alpha angle pre post resection 66°±7.6 ° 44°±4.9° respectively significantly different (p=0.003). Location shifted during medial anterior neck decreasing while IR remained on unaffected by version. Kruskal-Wallis testing decreased both groups (p<0.0003). Impingement ROM, as defined greater than 90° 10° respectively, only identified 5 15 anteversion models irrespective whether been performed. group, less any level (p<0.002) compared (p<0.04). When assessing change between groups, contrasting effects showing improvement improvements model (p=0.02). Conclusions: Decreasing demonstrates presence absence CAM lesion. After femoroplasty, has significant effect anteversion. seems predominant factor determining amount certain extent within even after suggesting that recurrent mechanical collision intra-articular damage seen FAI may still present true retroversion. This provides insight into changes expected following simulated osteotomy. [Table: see text]