Bone Abstracts

Introduction: A significant number of patient who have experienced previous surgical treatment for an osteoporotic hip fracture, experienced a subsequent hip fracture (SHF) on the opposite side. The incidence of asynchronous bilateral hip fractures is 1.7–14.8%. All hip fracture patients treated at five university hospitals in the Inchon and Bucheon area of Korea, were reviewed. The patients were divided into two groups, a group that had experienced subsequent hip fractures, and a group that had not. The authors analyzed the incidence of subsequent hip fracture (SHF) and its risk factors.

Materials and methods: We analyzed 2748 hip fracture patients from January 2000 to December 2010 at five university hospitals. Unilateral hip fracture patients who received no osteoporosis treatment at the time of the incident were included. Patients with history of a traffic accident, who had fallen from a height higher than the patient’s height, or with a history of pathologic fracture were excluded. Patient identification was cross checked between university hospitals in order to prevent double counting overlapping patients and to obtain an accurate count of incidence. Medical records were reviewed and presence of SHF, alcohol history, marriage status, dementia, dizziness, ASA score, osteoporosis treatment after fracture, BMI, and BMD (initial and last F/U) were analyzed.

Results: The average follow-up period was 12 months (range: 1–130 months). A total of 2546 patients (F: 1769, M: 777) who had experienced unilateral hip fractures were included. Of these, subsequent hip fractures were found in 202 patients (7.4%); (F: 169, M: 33). Mean age at the time of the first fracture was 79.2 years old (range: 50–100 years). The average interval between the first fracture and the SHF was 30.2 months (4 days–154 months). Female gender, a BMI under 22 kg/m², and being unmarried were revealed as the risk factors for subsequent fracture by multivariate analysis.

Conclusions: In this large-scale, retrospective, multicenter study, overall incidence of subsequent hip fractures was 7.4%. Independent risk factors of subsequent fracture were female gender, low BMI (<22 kg/m²), and being unmarried.