Abstract
Abstract
Introduction
Recurrent groin pain following periacetabular osteotomy (PAO) is a challenging problem. The purpose of our study was to evaluate the position and dynamics of the psoas tendon as a potential cause for recurrent groin pain following PAO.
Methods
Patients with recurrent groin pain following PAO were identified from a single surgeon series. A total of 13 patients with 18 hips (4.7%) out of a 386 PAO, had recurrent groin pain. Muscle path of the psoas tendon was accurately represented using 3D models from CT data were created with Mimics software. A validated discrete element model using rigid body springs was used to predict psoas tendon movement during hip circumduction and walking.
Results
Five out of the 18 hips did not show any malformations at the osteotomy site. Thirteen hips (72%) showed malformation secondary to callus at the superior pubic ramus. These were classified into: osteophytes at the osteotomy site, hypertrophic callus or non-union and malunion at the osteotomy. Mean minimal distance of the psoas tendon to osteophytes was found to be 6.24 mm (n=6) and to the osteotomy site was 14.18 mm (n=18).
Conclusions
Recurrent groin pain after PAO needs a thorough assessment. One need to have a high suspicion of psoas issues as a cause. 3D CT scan may be necessary to identify causes related to healing of the pubic osteotomy. Dynamic ultrasound of the psoas psoas tendon may help in evaluating for psoas impingement as a cause of recurrent groin pain in these cases.
