Physical Activity and Sedentary Behavior 6 Months after Musculoskeletal Trauma: What Factors Predict Recovery?

Background: Physical activity is increasingly recognized as an important marker of functional recovery following fracture. Objective: The objectives of this study were to measure sedentary behavior and physical activity 2 weeks and 6 months following fracture and to determine associated demographic and injury factors. Design: This was an observational study. Methods: Two weeks and 6 months following fracture, 83 adults who were 18 to 69 years old and had upper limb (UL) or lower limb (LL) fractures wore an accelerometer and an inclinometer for 10 days. We calculated sitting time, steps, moderate-intensity physical activity (MPA), and vigorous-intensity physical activity and conducted linear mixed-effects multivariable regression analyses to determine factors associated with temporal changes in activity. Results: At 6 months versus 2 weeks after fracture, participants sat less, took more steps, and engaged in more MPA. Participants with LL fractures sat 2 hours more, took 66% fewer steps, and engaged in 77% less MPA than participants with UL fractures. Greater reductions in sitting time were observed for participants in the youngest age group and with LL fractures, participants with high preinjury activity, and participants who were overweight or obese. For steps, greater improvement was observed for participants in the youngest and middle-Aged groups and those with LL fractures. For MPA, greater improvement was observed for middle-Aged participants and those with LL fractures. Limitations: Although this study was sufficiently powered for the analysis of major categories, a convenience sample that may not be representative of all people with musculoskeletal trauma was used. Conclusions: Working-Age adults with LL fractures had lower levels of physical activity 6 months after fracture than those with UL fractures. Older adults showed less improvement over time, suggesting that they are an important target group for interventions aimed at regaining preinjury activity levels