Background: Arthroplasty is a treatment for displaced fractures of the femoral neck in the elderly. The type of arthroplasty remains controversial as total hip replacements potentially have a higher dislocation rate. The study aimed to evaluate dual mobility cups to manage fractures of the femoral neck with the posterior approach in the elderly.
Methods:  This prospective study was conducted in Amritsar (Punjab), India. All patients with displaced fractures of the femoral neck treated via arthroplasty were operated on with the insertion of a dual mobility cup with the posterior approach. All patients were followed by clinical and radiological assessment at immediate post-op, 3 and 6 months, 1 and 3 years after surgery.
Results: Overall in the 240 patients, arthroplasty on the right hip of 121 (50.4%) and the left hip of 119 (49.6%) cases were performed. Majority of patients was male, and all patients were followed. The mean Harris hip score improved from 16.62 ± 6.34 preoperatively to 92.86 ± 2.28 at one-year follow-up and 95.20 ± 1.82 at three years’ follow-up. Three dislocations occurred, and Open Reduction was performed through a posterior approach under regional anesthesia for two patients. Closed Reduction was performed on one patient, and there was no recurrence of dislocation.
Conclusion: The low dislocation rate after acute total hip replacement using dual mobility design cups is comparable with hemi arthroplasties. The dual mobility cups may be considered a valuable option to prevent postoperative dislocation when treating displaced intra-capsular fractures of the proximal femur in elderly patients. A dual mobility cup reduces the incidence of postoperative instability even after using the posterior approach.