Dual mobility cup in hip fracture: Indications and clinical results compared with bipolar hip arthroplasty.

Abstract

The choice between hemiarthroplasty (HA) and total hip arthroplasty (THA) for displaced femoral neck fractures remains debated. There is increasing use in dual mobility cup total hip arthroplasty (DMC-THA) to prevent dislocations in these high-risk patients. Aim of this study is to retrospectively analyze patients treated in a single Center for femoral neck fracture comparing HA and DMC-THA in terms of: functional outcome, rate of complications and mortality. Between 2020 and 2022, 162 patients were included, 39 male and 123 female, with a mean age of 76 years old. HA were implanted in 82 cases and DMC-THA in 80 cases. INCLUSION CRITERIA WERE: age < 85 years old, American Society of Anesthesiologists (ASA) score below 3, minimum follow-up of 6 months. Overall, 124/162 of patients (77%) were surgically treated within 48 h from admission. The mean age for DMC-THA group was 74 years old and 78 years old for HA group. The overall mean surgical time was significantly higher in the DMC-THA group (P < 0.001). Mean hemoglobin (Hb) loss was 1.64 g/dl in the HA group and 1.72 g/dl in the DMC-THA group with no differences between the two groups (P = 0.573). There is no difference in survival of patients between the two groups (P = 0.7704). In the HA group, the mean one-month post-operative VAS score was 2.1, while in the DMC-THA group was 0.9. The Harris hip score was significantly better in DMC-THA group (P = 0.035) Dislocation never occured in the overall series. Infection occurred only in one patient with DMC-THA and was treated with debridement. Periprosthetic fracture occurred in 2 cases of DMC-THA both within 1 month from the first surgery; one was treated with revision femoral stem and the second one with fixation. DMC-THA offer better functional results than HA in elderly patients with femur neck fractures. The mean surgical time was longer in DMC-THA but this did not influence blood loss, time of discharge or one-year mortality. In our series dislocation never occurred in both groups.