ObjectiveTo study the occurrence and risk factors of dislocation after total hip arthroplasty(THA) for osteoarthritis.

MethodsA total of 266 patients with osteoarthritis were treated with THA, and followed up for 6 months.The occurrence of dislocation of the hip joint was recorded.The patients with postoperative dislocation of the hip joint were set as the dislocation group, and the patients without dislocation were set as undislocation group.The surgical indicators and medical record in two groups were analyzed using univariate and logistic regression analysis to explore the independent risk factors of postoperative dislocation in patients treated with THA.

ResultsAmong 266 patients with osteoarthritis, 25 cases with dislocation after THA were found, and the dislocation rate was 9.40%.The differences of the age, artificial femoral head diameter, history of hip surgery, postoperative blood loss, anterior angle of femoral prosthesis and postoperative femoral eccentricity between two groups were statistically significant(P < 0.05 to P < 0.01), and the differences of the gender, body mass index, surgical approach, combined diabetes mellitus, operative time, postoperative transfusion rate, postoperative drainage volume and operative side between two groups were not statistically significant(P>0.05).The results of multivariate logistic regression analysis showed that age >75 years, female, diameter of artificial femoral head < 30 mm, history of hip surgery, posterolateral approach and anteversion of femoral prosthesis >10° were the independent risk factors of dislocation after aosteoarthritis treated with THA(P < 0.05).

ConclusionsThe hip joint with osteoarthritis is prone to dislocation after THA, the age >75 years, female, artificial femoral head diameter < 30 mm, hip surgery history and posterior lateral approach can increase the risk of dislocation.