Fragility fractures are bad enough, but to what extent do they trigger additional skeletal muscle loss?
A multicenter team set out to answer that question as well as to better understand the relationship of fragility fractures with malnutrition and physical function.
Finally, the team hoped to identify key risk factors for skeletal muscle loss in patients who had been treated with operative fixation of an isolated femoral fragility fracture.
Their multicenter, prospective observational study, “Substantial Loss of Skeletal Muscle Mass Occurs After Femoral Fragility Fracture,” appears in the November 15, 2023, edition of The Journal of Bone and Joint Surgery.
“Loss of function and independence are problems after hip fracture in older adults,” co-author Michael Willey, M.D., clinical associate professor of orthopedics and rehabilitation at the University of Iowa, told OTW. “Additionally, malnutrition is extremely common and associated with low muscle mass.”
“Our group believes that malnutrition and subsequent loss of muscle mass after fracture leads to this loss of function and independence. Our goal is to identify nutrition interventions to prevent loss of muscle mass after injury. Our goal was to document the amount of muscle that is lost after hip fracture and how that correlates with malnutrition and loss of function.”
The researchers assessed skeletal muscle mass within 72 hours of admission and then again at 6 weeks, 3 months, and 6 months. At the time of injury, 30 patients (33%) were sarcopenic and 44 (49%) were at risk for malnutrition or had malnutrition.
From the time of injury to 6 weeks:
- participants lost an average of 2.4 kg (9%) of skeletal muscle mass.
- This early loss did not recover by 6 months (1.8 kg persistent loss compared with baseline)
- participants with normal nutritional status lost more skeletal muscle mass from baseline to 6 weeks after injury compared with those with malnutrition (1.3 kg more loss).
- A 1 kg decrease in skeletal muscle mass was associated with an 8-point decrease in the Patient-Reported Outcomes Measurement Information System Physical Function score.
According to co-author Dr. Willey, “Substantial loss of skeletal muscle mass occurs after hip fracture. Loss of function correlated with loss of skeletal muscle mass. Older adults with adequate baseline nutrition and higher muscle mass loss the greatest volume of muscle mass after injury.”
“We hypothesized that these patients lost more muscle and function after injury because of a higher baseline health status, indicating that these patients would also be a population that would benefit from nutrition interventions after injury.”
“High-quality randomized clinical trials are needed to define the impact of nutrition interventions on muscle mass, function, and independence after hip fracture in older adults.”
