Document Type : RESEARCH PAPER
Orthopedic department, Faculty of Medicine for Girls ,AlAzhar University, Cairo, Egypt
Objectives: Dislocation rate of total hip arthroplasty (THA) can be as high as 20% for patients with
fracture neck of femur, which is a disastrous complication in these vulnerable patients. Numerous
techniques, including bipolar arthroplasty and constrained liner, have been adopted to minimize the
risk of dislocation. We aimed to evaluate the role of dual mobility Cups in treating patients with fractures
of the femoral neck with high risk of postoperative dislocation due to neuromuscular instability
Methods: A prospective cohort study was conducted (place is blinded as asked during submission), between 2016
and 2019, with a post-operative follow up period of two years. We included skeletally mature patients with femoral
neck fractures having neuromuscular disorders and cognitive dysfunction who are candidates for THA above 60
years. Patients were then followed up clinically and radiographically at the clinic using Harris Hip Score (HHS) and
x-rays at six weeks, six months, one year and two years postoperatively.
Results: Twenty patients (20 hips) with femoral neck fractures with high risk of postoperative dislocation due to
neuromuscular instability disorders undergoing dual mobility cup were included. The mean age of patients was 70.5
±6.42 years. There is highly significant difference between HHS preoperatively and postoperatively (six weeks, six
months and one, two years) p<0.001.Infection occurred in one case (5 %), sciatic nerve injury occurred in one case
(5%), and none of the patients had postoperative dislocation.
Conclusion: Dual mobility cup is effective in preventing early dislocation in patients suffered from fracture neck of
femur with muscle weakness due to neurologic disorders.
Level of evidence: IV