Development of Cam Impingement following Operative Fixation of Acetabular Fractures

The development of femoroacetabular impingement following acetabular fracture fixation is under-recognized. This study assessed radiographic changes of the hip joint after acetabular fracture fixation, and the clinical implications of associated radiographic changes. Institutional review of patients under age 40 who underwent acetabular fracture fixation from 2010 to 2016 with minimum 1-year radiographic follow-up was performed. Two independent evaluators compared immediate postoperative radiographs and those at final follow-up for basic radiographic parameters. Chi-squared test, Fisher's exact test, and two-tailed t-tests were used to compare those with and without cam lesion development. Two-hundred twenty-four hips were reviewed, with 55 hips (53 patients) meeting inclusion criteria (age = 29.2 years, 60% male, average follow-up = 2.1 years). Average α angle increased from 53.8 to 75.5 degrees postfixation (p