The Etiology of Residual Symptoms after Hip Arthroscopic Treatment of Femoroacetabular Impingement: Analysis Using Finite Element Modeling / 대한정형외과학회잡지

ABSTRACT

PURPOSE: To analyze, using finite element model analysis, the causes of postoperative pain in patients who had arthroscopic treatment for femoroacetabular impingement (FAI). MATERIALS AND METHODS: Ten patients with FAI treated by arthroscopic surgery between July 2004 and July 2007 were selected. Five cases whose condition improved to a pain score of 3 postoperatively were assigned to comparative group A and 5 cases who had a second operation done due to a pain score of 1 were assigned to experimental group B. Finite element model analysis was done for the impingement test position. Femoral offset and alpha angle were measured to compare with contact pressure or von Mises stress. RESULTS: Preoperative von Mises stress and contact pressure were all higher in group B than group A. Maximal stress and pressure location was the anterolateral surface of the femoral head and neck, and this location was removed more accurately in group A. CONCLUSION: Finite element model analysis of FAI indicated that incomplete removal of a bump was the cause of pain, and that accurate location of the lesion and adequate bump removal are the definitive factors in reducing pain.