We have recently seen and successfully treated four patients with iliopsoas-related groin pain post total hip replacement. Their clinical pictures were all typical of iliopsoas-related groin pain. After the exclusion of other causes, surgical release of this tendon resulted in successful treatment with complete resolution of symptoms. We subsequently carried out an anatomic dissection of the iliopsoas tendon on a cadaver torso to better understand the relationship between the iliopsoas tendon and the acetabular component in total hip replacement surgery. It was apparent that cup position and placement were critical to prevent contact of the iliopsoas tendon with the rim of the acetabular component. We have subsequently modified our positioning of the acetabular component.