INCIDENCE OF DISLOCATION AFTER TOTAL HIP REPLACEMENT WITH METAL ON POLYETHYLENE SYSTEM

Abstract

Background: Total hip arthroplasty is the preferred treatment for end-stage hip joint disease, preventing dislocations and enhancing durability and functionality. It requires careful planning, surgical precision, and postoperative care.

Objective: To determine the frequency of dislocation after primary total hip replacement with metal on polyethylene system

Material and Methods: This retrospective study was conducted at Mardan Medical Complex Mardan, Mercy Teaching Hospital Peshawar and Mateen Medical Center Peshawar, Pakistan, examined the clinical records of 145 patients over 40 years old who underwent total hip replacement for end-stage hip disease and proximal femoral fracture surgery. Data was analyzed using descriptive statistical analysis and Chi square test.

Results: The study found a dislocation rate of 9.66% in 14 patients, with 50% occurring in females and 50% in males. Regarding etiology of hip disease 21%, 29% and 50% dislocations occurred in patients undergone total hip arthroplasty for a vascular necrosis of femoral head, osteoarthritis hip and proximal femur fracture respectively(p value= 0.3348).35.71% patients with poster lateral approach for arthroplasty and 64.29% patients with direct lateral approach for arthroplasty had artificial hip dislocation. 50% patients with inclination angle >45 degrees of acetabular cup and 5% with inclination angle ≤45 degrees of ace tabular cup developed artificial hip dislocations.

Conclusion: Acetabular inclination >45° was significantly associated with increased hip dislocation risk in our study sample, suggesting it is an important surgical consideration.