Risk factors for Total Hip Arthroplasty dislocation in elective patients

Abstract

Purpose: To assess the rate of dislocation and evaluate the risk factors associated with THA dislocation in Portuguese elective patients. Methods: A retrospective assessment of all patients submitted to elective THA in a Portuguese tertiary hospital with hip and spine dedicated units, between 2012 and 2017 was performed. Clinical and THA-related data was reviewed, alongside dislocation reports and information on associated lumbar spine surgery. The relationship between risk factors and dislocation was analysed. Statistical analysis was conducted with SPSS (28th version) Results: 936 patients were included, with a mean age of 63.27 ± 15.78 (66.71 ± 10.80 in the dislocation group). Patient's age (p=0.339), gender (p=0.394), BMI (p=0.989) hypertension (p=0.952), cardiac disease (p=0.633) and renal disease (p=0.312) did not differ significantly between patients with and without dislocation. Diabetes was significantly more prevalent in patients with dislocation (p=0.026). The main cause for revision of arthroplasty was periprosthetic fracture (31.75%), followed by infection (30.16%) and dislocation (22.22%). Patients with an episode of dislocation were more likely to need a revision surgery than the ones with no dislocation. 96.8% of dislocations happened in the first 24 months. Conclusion: Patients with diabetes seem to have higher risk of dislocation. No other condition showed a significant association with dislocation rate. Dislocation occurs most often in the first two years and patients with instability are more likely to go through revision surgery.

Keywords: arthroplasty, risk factors, hip dislocation, comorbidity