The Causative Factors of Dislocation after Total Hip Arthroplasty

Suh, Kuen Tak; Nam, Tae Wook; Choi, Young Jun

Abstract

PURPOSE
We performed a clinical study and a matched-set radiographic analysis to determine the factors that contribute to dislocation after total hip arthroplasty.
MATERIALS AND METHODS
We reviewed 346 total hip arthroplasties (46 were revision procedure) followed by more than 1 year from January, 1992 to June, 1998. A clinical study was performed for dislocated group (16 cases) and non-dislocated group as to disease and patient's factors and prosthesis type. A radiographic analysis was performed for dislocated group and matched control group (32 cases) to evaluate operative factors. RESULT: Dislocation occurred in sixteen cases (4.6%) of the 346 total hip arthroplasties. There was no statistical correlation between age, gender, preoperative diagnosis or prior hip surgery in disease and patient's factor and dislocation. The patients who had a history of alcoholism (more than 0.8 bottle of Soju a day) had the significant difference in dislocation rate in comparison with the patients who did not have such a history. Operative factors were studied by radiographic analysis for sixteen hips that had dislocated and thirty-two that had not. We detected no relationships between the angle of the anteversion and inclination of the cup, leg length difference or the rate of horizontal offset and the risk of dislocation. The prosthesis type and acetabular liner also had no relationships with the dislocation.
CONCLUSION
Although the causative factors for dislocation after total hip arthroplasty were not related to operative factor and prosthesis type, alcoholism in patient related factors was important.