Ankle fractures are a common orthopedic injury, occurring at an annual incidence of 187 fractures per 100,000 people. Certain ankle injuries have been associated with patient demographics such as obesity and smoking. Unlike fractures of the distal radius, hip, and spine, osteoporosis does not seem to be a major risk factor for ankle fractures. A study of more than 3500 patients with ankle fracture revealed their average body mass index (BMI), calculated as the weight in kilograms divided by height in meters squared, to be higher than the general population across all age and gender categories. Naturally, these injuries affect the lower extremity mobility significantly, which itself is a risk factor for obesity. Although overweight adults with disabilities are generally as likely to attempt weight loss as those without disabilities, overweight adults having difficulty walking or using a mobility aid are the exception. In part, this stems from physicians not counseling this population on the importance of physical exercise. Physicians may focus more on diet than exercise in light of limited mobility; however, recent studies suggest that reduced energy expenditure is more causative than increased food intake in the development of obesity.

The implications to one’s health of being overweight are numerous. More than 80% of type 2 diabetes can be attributed to obesity, which may also account for many diabetes-related deaths. The association between diabetes and complications of ankle injuries has been well documented. In addition, obesity has been associated with an increased risk of deep vein thrombosis (DVT) and pulmonary embolus (PE), which are concerns with any lower extremity injury. Finally, obesity syndrome predisposes patients to osteoarthritis by altering cartilage and bone metabolism independent of weight bearing, as evidenced by the involvement of non-weight-bearing joints. The tibiotalar joint is subject to joint reaction forces of 4.5 times the body weight during walking and 10 times the body weight with running. Posttraumatic arthritis in the setting of a biologic predilection for osteoarthritis can be devastating to mobility. Although there may be some protective effect of obesity on bones, with recent evidence showing that leptin resistance in obese individuals may have a favorable effect on bone mass, ankle injuries in the setting of obesity are fraught with complications.