Treatment of mixed type femoroacetabular impingement using safe surgical hip dislocation in adults

This study aims to assess the experience gained in a single institution in the treatment of mixed type femoroacetabular impingement (FAI) using safe surgical hip dislocation (SSHD) technique.

In this study, 22 hips of 21 patients (7 males, 14 females; mean age 33.8±10.6 years; range 19-52 years) treated by SSHD technique in our clinic between October 2009 and October 2014 were retrospectively evaluated. Preoperative and final Harris hip scores (HHS) and alpha angles were compared. Age, gender, laterality, impingement tests, preoperative HHS, cam and pincer type FAI radiographic indicators and intraoperative articular findings were assessed in terms of their influence to the final functional outcomes.

Mean duration of the symptoms was 29.5 months. Groin pain, activated by flexion and internal rotation of the hip, was the main symptom. A radiographic diagnosis of "mixed type FAI" was made in all hips. Mean follow-up duration of 22 hips was 48 months. The difference between the mean preoperative and latest HHS was statistically significant (60.0 vs. 87.6 points, p<0.001). The treatment was considered satisfactory in 17 of 22 hips (77%) having a mean HHS of 95.0 points. Hips having a preoperative HHS of less than 60 points were more prone to unsatisfactory outcome. Among the investigated patient-dependent, clinical, radiographic variables and intraoperative articular findings, coxa profunda sign in a plain radiograph was found correlated with a higher rate of unsatisfactory outcome (p=0.040).

Safe surgical hip dislocation procedure has a success rate of 77% after a mean follow-up of four years. Coxa profunda sign is associated with the unsatisfactory clinical outcome. Preoperative HHS of less than 60 points seems to be a negative predictive variable on the clinical outcome.