Purpose of the study: This retrospective analysis compared surgical treatments of femoral neck fractures in patients aged over 80 years.

Material and methods: Two hundred femoral neck fractures (Garden 3 and 4) were treated in three different manners: total prosthesis with a retaining cup (74 patients), intermediary prosthesis (58 patients), and osteosynthesis (68 patients). Indications were the same, but the periods of treatment were successive. Study variables were: mortality, number of revisions, duration of hospital stay, discharge to home or rehabilitation center, cost per hospital day. Follow-up was at least two years. The chi-square test was applied with p< 0.05.

Results: Mortality was similar for the three groups: eight deaths during stay in orthopedic unit (4%), three after total prosthesis (4%), three after osteosynthesis (5%) and two after intermediary prosthesis (3%). The difference was nonsignificant (p=0.24). Among the total prostheses, five dislocations (6.7%) required anesthesia despite the retaining cup. The rate of dislocation was 12% for intermediary prostheses and to avoid recurrence four revisions were needed to totalize an intermediary prosthesis with a retaining cup. Among the osteosynthesis cases, the rate of revision was 25%; transformation to a total prosthesis was necessary for 17% and material removal with resection of the head and neck was necessary in 8%. One total prosthesis and one intermediary prosthesis had to be removed because of infection. Resection of the head and neck for infection also occurred in one patient with an intermediary prosthesis. The rate of revision for an orthopedic problem was significantly less (p< 0.01) in the total prosthesis group. At last follow-up, or before death, patients with a total prosthesis were more independent and returned to their home significantly more often than patients treated with osteosynthesis. The economic cost of these interventions were not significantly different, the cost of the implant being insignificant compared with the cost of hospitalization and reeducation of this very elderly population.

Discussion: Total hip arthroplasty is a recognized treatment for painful degenerative hip disease. Historically, the total prosthesis was not considered as a first-intention treatment for fractures of the femoral neck in elderly subjects due to the risk of intraoperative blood loss, the risk of infection, and the risk of dislocation if a hip stabilization mechanism was not applied. This study demonstrated that, in light of the complications observed with the other methods, progress in anesthesia and use of implants avoiding dislocation can be proposed as first-intention treatment for total prosthesis patients who suffer a fracture of the femoral neck.