Authors' reply Cobb correspondence re: J-E. Gjertsen, S. A. Lie, T. Vinje, et al. More re-operations after uncemented than cemented hemiarthroplasty used in the treatment of displaced fractures of the femoral neck: An observational study of 11 116 hemiarthroplasties from a national register. J Bone Joint Surg [Br] 2012;94-B:1113-1119.

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More re-operations after uncemented than cemented hemiarthroplasty used in the treatment of displaced fractures of the femoral neck: an observational study of 11,116 hemiarthroplasties from a national register.

Using data from the Norwegian Hip Fracture Register, 8639 cemented and 2477 uncemented primary hemiarthroplasties for displaced fractures of the femoral neck in patients aged > 70 years were included in a prospective observational study. A total of 218 re-operations were performed after cemented and 128 after uncemented procedures. Survival of the hemiarthroplasties was calculated using the Kaplan-Meier method and hazard rate ratios (HRR) for revision were calculated using Cox regression analyses. At five years the implant survival was 97% (95% confidence interval (CI) 97 to 97) for cemented and 91% (95% CI 87 to 94) for uncemented hemiarthroplasties. Uncemented hemiarthroplasties had a 2.1 times increased risk of revision compared with cemented prostheses (95% confidence interval 1.7 to 2.6, p < 0.001). The increased risk was mainly caused by revisions for peri-prosthetic fracture (HRR = 17), aseptic loosening (HRR = 17), haematoma formation (HRR = 5.3), superficial infection (HRR = 4.6) and dislocation (HRR = 1.8). More intra-operative complications, including intra-operative death, were reported for the cemented hemiarthroplasties. However, in a time-dependent analysis, the HRR for re-operation in both groups increased as follow-up increased. This study showed that the risk for revision was higher for uncemented than for cemented hemiarthroplasties.

Internal screw fixation compared with bipolar hemiarthroplasty for treatment of displaced femoral neck fractures in elderly patients.

BACKGROUND: Internal fixation and arthroplasty are the two main options for the treatment of displaced femoral neck fractures in the elderly. The optimal treatment remains controversial. Using data from the Norwegian Hip Fracture Register, we compared the results of hemiarthroplasty and internal screw fixation in displaced femoral neck fractures. METHODS: Data from 4335 patients over seventy years of age who had internal fixation (1823 patients) or hemiarthroplasty (2512 patients) to treat a displaced femoral neck fracture were compared at a minimum follow-up interval of twelve months. One-year mortality, the number of reoperations, and patient self-assessment of pain, satisfaction, and quality of life at four and twelve months were analyzed. Subanalyses of patients with cognitive impairment and reduced walking ability were done. RESULTS: In the arthroplasty group, only contemporary bipolar prostheses were used and uncemented prostheses with modern stems and hydroxyapatite coating accounted for 20.8% (522) of the implants. There were no differences in one-year mortality (27% in the osteosynthesis group and 25% in the arthroplasty group; p = 0.76). There were 412 reoperations (22.6%) performed in the osteosynthesis group and seventy-two (2.9%) in the hemiarthroplasty group during the follow-up period. After twelve months, the osteosynthesis group reported more pain (mean score, 29.9 compared with 19.2), higher dissatisfaction with the operation result (mean score, 38.9 compared with 25.7), and a lower quality of life (mean score, 0.51 compared with 0.60) than the arthroplasty group. All differences were significant (p < 0.001). For patients with cognitive impairment, hemiarthroplasty provided a better functional outcome (less pain, higher satisfaction with the result of the operation, and higher quality of life as measured on the EuroQol visual analog scale) at twelve months (p < 0.05). CONCLUSIONS: Displaced femoral neck fractures in the elderly should be treated with hemiarthroplasty.