Second Hip Fractures at Chiang Mai University Hospital
Prasit Wongtriratanachai MD*, Siripong Chiewchantanakit MD*, Tanawat Vaseenon MD*, Sattaya Rojanasthien MD*, Taninnit Leerapun MD*
Affiliation : * Department of Orthopaedics, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
Background : Hip fractures are a major public health problem. Patients who have suffered a hip fracture have an increased
risk of a subsequent hip fracture. This study examines the incidence of second hip fractures and attempts to identify underlying
risk factors.
Objective : To examine the incidence of second hip fractures in osteoporotic patients at Chiang Mai University Hospital and
to identify risk factors related to second hip fractures.
Material and Method: A retrospective review was conducted of all low-energy mechanism hip fracture patients admitted
during 2008 and 2009. Analysis of second hip fractures was conducted using survival analysis and logistic regression
analysis.
Results : A total of 191 patients were observed for 391.68 person-years (mean 2.05 person-years per patient). Among that
group, nine second hip fractures were identified, an overall incidence rate of 0.023 second fractures per person-year. Second
hip fractures tended to occur within the first year following an initial hip fracture. There were no significant differences
related to either gender or comorbid medical conditions. Logistic regression analysis revealed that increased risk of a
second hip fracture was associated with age (highest between 80 to 89 years) and patients who were not treated for
osteoporosis following their initial fracture.
Conclusion : The incidence of second hip fractures at Chiang Mai University Hospital was 0.023 per person-year. Careful
follow-up of older patients, especially those over 80, and treatment of osteoporosis with bisphosphonate plus vitamin D and
calcium supplements was correlated with a reduction in the incidence of second hip fractures.
Keywords : Incidence of hip fracture, Second hip fracture, Chiang Mai, Thailand
