Abstract: BACKGROUND: Secondary fracture has gradually become the most problematic postoperative health threat in elderly hip fracture patients. However, the findings on the occurrence of secondary fracture and risk factors are still controversial.
OBJECTIVE: To investigate the incidence and distribution of postoperative secondary fractures in elderly patients with hip fractures, and to further investigate the risk factors for postoperative secondary fractures in these patients.
METHODS: A total of 573 patients aged 60-85 years who underwent surgical treatment at the First Affiliated Hospital of Soochow University for initial femoral neck fracture or intertrochanteric femoral fracture between January 2018 and December 2020 were retrospectively analyzed. Patients were categorized into the secondary fracture group and the no secondary fracture group according to the occurrence of secondary fracture at the final follow-up. The differences in indicators between the two groups were compared, and indicators that might be meaningful were included in multivariate logistic regression analysis to explore the independent risk factors for postoperative secondary fracture.
RESULTS AND CONCLUSION: (1) The incidence of postoperative secondary fractures in elderly hip fracture patients was 20.2% (116/573). The sites and proportions of secondary fractures were as follows: 68 lower extremity fractures, accounting for 58.6%; 33 spine fractures, accounting for 28.5%; and 15 upper extremity fractures, accounting for 12.9%. (2) Comparison of baseline data showed that there was a significant difference between patients in the secondary fracture group and patients in the group without secondary fracture in terms of age, history of cerebrovascular disease, history of Parkinson's disease, preoperative prealbumin level, mechanism of injury for the initial hip fracture, Singh index grading on the healthy side, and early postoperative mobility (P < 0.05). (3) Multivariate logistic regression analysis showed that history of Parkinson's disease (OR=3.00, 95%CI=1.05-8.43, P=0.036) and need for assistance in early postoperative mobility (OR=2.78, 95%CI=1.39-5.51, P=0.003) were independent risk factors for secondary fractures. (4) The incidence of postoperative secondary fractures in elderly hip fracture patients is not low. In the future, multidisciplinary co-management of patients, especially those with a history of comorbid Parkinson's disease, should be strengthened and enhanced recovery after surgery strategy should be persistently promoted to reduce the incidence of secondary fractures.

Key words: elderly, hip fracture, secondary fracture, Logistic regression analysis, risk factor, vascular disease, Parkinson's disease