Overview
Research Article Title: Amino Acid Supplementation May Help Prevent Muscle Wasting After Orthopedic Surgery, but Additional Studies Are Warranted: A Systematic Review of Randomized Clinical Trials
Authors: Elizabeth Brown et al.
Published in: HSS Journal: The Musculoskeletal Journal of Hospital for Special Surgery
Date of Publication: January 8, 2025
Link to Article →
Summary
Recent focus has been placed on peri-operative optimization, especially nutrition and metabolic health, to help reduce surgical complications and improve outcomes. Essential amino acids (EAA) supplementation for orthopedic and spine procedures can help improve patient outcomes. Key Findings:
- EAA supplementation in the perioperative period can aid in the prevention of skeletal muscle loss.
- EAA supplementation can help improve post-operative function such as range of motion, strength, and mobility.
Methodology
A total of 10 randomized controlled trials (RCTs) from 2002–2023 met the inclusion criteria for this systematic review to evaluate EAA supplementation in trauma, adult reconstruction, and spine surgery. Of these studies, three implemented EAA supplementation seven days prior to the procedure.
- Total knee arthroplasty (TKA): n = 3
- Total hip arthroplasty (THA): n = 2
Half of the studies showed improved muscle size or composition and better functional outcomes with EAA supplementation.
Why It Matters
Amino acid mobilization is a hallmark of the catabolic state associated with surgery, and EAA supplementation helps to mitigate the effects of skeletal muscle wasting.
- Three studies found significantly greater quadriceps muscle volume after TKA with pre-operative EAA supplementation. Conclusion: pre-operative EAA supplementation for one week prior through 2–6 weeks post-operation reduced muscle loss.
- Three studies examining muscle size and/or composition did not find a significant difference with EAA supplementation but did note that the placebo group lost a significant amount of fat-free mass compared to the EAA group after six weeks of supplementation.
- Seven studies analyzed changes in grip strength; only one showed a significant increase in mean grip strength for sarcopenic patients with EAA supplementation.
- Three studies reported significant improvements in lower extremity mobility (TUG test, timed walks, and stair assessment) with EAA supplementation.
Limitations
The current body of research is limited and has a high degree of variability in creating effective dosing strategies. Dosage, duration, and timing of interventions vary widely across the studies. Currently, there are no standards to establish the maximum effective dosage and formulation of EAA supplementation.
Final Thoughts
Optimizing perioperative nutritional status is associated with improved surgical outcomes. Overall, high-level evidence supports the potential benefits of EAA supplementation; however, it’s important to note that this is a synergistic approach that works best with appropriate nutrition management, including preoperative nutritional assessment and targeted nutritional supplementation.
This article was written by Katie Frushour, MS, RD, CSSD, a dietitian at Mend.
