Buller LT, Menken L, Hawkins EJ, et al. - This study was undertaken to investigate the incidence, natural history, response to treatment, and risk factors for anterior iliopsoas impingement (AIPI) after direct anterior approach (DAA) total hip arthroplasty (THA). Researchers retrospectively examined a total of 600 patients (655 hips) who had undergone primary DAA THA between January 1, 2009, and January 4, 2014. They estimated AIPI incidence. They further tested natural history and response to a stepwise treatment approach. The radiographic anterior acetabular component overhang was assessed. Risk factors for the development of AIPI were identified by using asymptomatic controls. A total of 518 patients (559 hips) were included in the study. After DAA THA, AIPI is a cause of groin pain, which often improves with conservative measures. The data exhibited that for AIPI, significant predisposing factors include female gender, small native femoral head diameter, increased acetabular component to femoral head diameter ratio, and most notably, any measurable acetabular component overhang.