In the February 1, 2017 edition of The Journal, Deren et al. provide an important analysis of muscle mass as it relates to mortality in older patients with an acetabular fracture. Among 99 fracture patients studied retrospectively, 42% had sarcopenia, defined in this study as a skeletal muscle index at the L3 vertebral body of <55.4 cm2/m2 for men and <38.5 cm2/m2 for women.
Deren et al. found that low BMI was associated with sarcopenia and that patients with sarcopenia were significantly more likely than patients without sarcopenia to sustain their skeletal injury from a low-energy mechanism. Sarcopenia was also associated with a higher risk of 1-year mortality, especially when in-hospital deaths were excluded. While the authors note that there’s no consensus definition for clinically diagnosing sarcopenia, they conclude that “sarcopenia based on the skeletal muscle index may be a better predictor of mortality than other commonly used classification
systems.”
There are important subtextual messages in this study for all physicians who manage geriatric patients. Maintenance of muscle mass by resistance exercise (lifting weights, isometrics, etc.) is of critical importance in limiting fall risk and maintaining good balance and bone density. Dietary considerations are intertwined with exercise in maintaining muscle mass among older patients. Resistance training and cardio exercise help to maintain appetite, and adequate protein intake is of utmost importance. When families and medical teams work together, the risk of sarcopenia can be minimized, resulting in lower rates of falls, fewer low-energy fractures, and less mortality.
Marc Swiontkowski, MD
JBJS Editor-in-Chief
