Cumulative incidence and treatment of non-simultaneous bilateral femoral neck fractures in a cohort of one thousand two hundred and fifty patients.

ABSTRACT

PURPOSE: In the Netherlands, over 20,000 patients sustain a hip fracture yearly. A first hip fracture is a risk factor for a second, contralateral fracture. Data on the similarity of the treatment of bilateral femoral neck fractures is only scarcely available. The objectives of this study were to determine the cumulative incidence of non-simultaneous bilateral femoral neck fractures and to describe the patient characteristics and treatment characteristics of these patients. METHODS: A database of 1,250 consecutive patients with a femoral neck fracture was available. Patients with a previous contralateral femoral neck fractures were identified by reviewing radiographs and patient files. Patient characteristics, previous fractures, hip fracture type and details on treatment were collected from the patient files. RESULTS: One hundred nine patients (9%, 95% confidence interval 7-10%) had sustained a non-simultaneous bilateral femoral neck fracture. The median age at the first fracture was 81 years; the median interval between the fractures was 25 months. Overall, 73% was treated similarly for both fractures in terms of non-operative treatment, internal fixation or arthroplasty. In patients with identical Garden classification (30%), treatment similarity was 88%. CONCLUSIONS: The cumulative incidence of non-simultaneous bilateral femoral neck fractures was 9%. Most patients with identical fracture types were treated similarly. The relatively high risk of sustaining a second femoral neck fracture supports the importance of secondary prevention, especially in patients with a prior wrist or vertebral fracture.