Evaluation of anterior inferior iliac spine impingement after hip arthroscopic osteochondroplasty using computer simulation analysis

• Main Authors: Naomi Kobayashi, Hyonmin Choe, Hiroyuki Ike, Shota Higashihira, Daigo Kobayashi, Shintaro Watanabe, So Kubota, Yutaka Inaba
• Format: Article
• Language: English
• Published: SAGE Publishing 2020-07-01
• Series: Journal of Orthopaedic Surgery
• Online Access: https://doi.org/10.1177/2309499020935533

Background: Anterior inferior iliac spine (AIIS) impingement is an important risk factor for revision hip arthroscopy. Although a morphological classification system is available, evaluating AIIS impingement with respect to joint kinematics remains a challenge. Purpose: To use computer simulation analysis to ascertain the prevalence of AIIS impingement before and after osteochondroplasty. Methods: A total of 35 joints from 30 cases (20 males and 10 females; average age: 43.3 ± 13.7 years) were analyzed. All joints had cam morphology and underwent hip arthroscopic osteochondroplasty. A three-dimensional model of each joint was constructed pre- and postoperatively. Joint kinematic simulation software (ZedHip®, Lexi, Tokyo) was used to identify the impingement point on the acetabular side and the incidence (expressed as a percentage) of AIIS impingement calculated. Radiographic and clinical evaluation was performed pre- and postoperatively. Results: AIIS impingement was observed postoperatively in six joints but preoperatively in only one joint. The rate of AIIS postoperative impingement was significantly higher than that of preoperative impingement. All impingement points were located on the inferior aspect of the AIIS apex. However, there were no significant differences between the AIIS impingement and non-impingement groups in terms of clinical outcome. Conclusion: The incidence of AIIS impingement after osteochondroplasty was 17% by computer simulation analysis. Osteochondroplasty may result in subsequent AIIS impingement.