Conditionally Essential Amino Acid Supplementation Reduces Postoperative Complications and MuscleWasting After Fracture Fixation

A Randomized Controlled Trial

Nathan R. Hendrickson, MD, John Davison, MPH, Natalie A. Glass, PhD, Erin S. Wilson, MD, Aspen Miller, BS, Steven Leary, MA, William Lorentzen, BS, Matthew D. Karam, MD, Matthew Hogue, MD, J. Lawrence Marsh, MD, and Michael C. Willey, MD

Investigation performed at the Department of Orthopedics & Rehabilitation, University of Iowa, Iowa City, Iowa

Background: Postoperative complications and substantial loss of physical function are common after musculoskeletal trauma. We conducted a prospective randomized controlled trial to assess the impact of conditionally essential amino acid (CEAA) supplementation on complications and skeletal muscle mass in adults after operative fixation of acute fractures.

Methods: Adultswhosustainedpelvicandextremityfracturesthatwereindicatedforoperativefixationatalevel-Itrauma center were enrolled. The subjects were stratified based on injury characteristics (open fractures and/or polytrauma, fragility fractures, isolated injuries) and randomized to standard nutrition (control group) or oral CEAA supplementation twice daily for 2 weeks. Body composition (fat-free mass [FFM]) was measured at baseline and at 6 and 12 weeks postoperatively. Complications were prospectively collected. An intention-to-treat analysis was performed. The relative risk (RR) of complications for the control group relative to the CEAA group was determined, and linear mixed-effects models were used to model the relationship between CEAA supplementation and changes in FFM.

Results: Four hundred subjects (control group: 200; CEAA group: 200) were enrolled. The CEAA group had significantly lower overall complications than the control group (30.5% vs. 43.8%; adjusted RR = 0.71; 95% confidence interval [CI] = 0.55 to 0.92; p = 0.008). The FFM decreased significantly at 6 weeks in the control subjects (–0.9 kg, p = 0.0205), whereas the FFM was maintained at 6 weeks in the CEAA subjects (20.33 kg, p = 0.3606). This difference in FFM was not seen at subsequent time points.

Conclusions: Our results indicate that CEAA supplementation has a protective effect against common complications and early skeletal muscle wasting after operative fixation of extremity and pelvic fractures. Given the potential benefits of this inexpensive, low-risk intervention, multicenter prospective studies in focused trauma populations are warranted.