Student Research

Quantitative Model of PLG 10-90 to Simulate Mechanical Responses for Anterior Cruciate Ligament Reconstructive Innovation

There are an estimated 100,000 cases of torn Anterior Cruciate Ligaments (ACL) in the United States each year. Although autografts and allografts are approved treatments, they are expensive, labor intensive, cause donor site morbidity, and require a lengthy patient recovery process. Synthetic implants eliminate the harvesting procedure and have great biocompatibility, however their long-term effects are not understood. Understanding the full scope of mechanical properties of a synthetic material that closely matches those of native ligaments is imperative for ACL reconstruction innovation. PLG 10-90 (L-lactide-co-glycolide) is an absorbable copolymer which degrades into harmless products and is utilized as suture in orthopedic surgery. The copolymer sufficiently matches average native ACL tensile strength, percent elongation to fracture, and the degradation time is approximately that of ACL regrowth time. These factors make PLG 10-90 a strong candidate to provide structural support during the ACL recovery time and degrade thereafter. This research will determine a quantitative model of PLG 10-90 whose variables are expressed as decaying functions to account for the degradation of the copolymer. The model will probe the viscous and elastic components of PLG 10-90 and may be incorporated into ANSYS, an advanced simulation software. ANSYS may accurately simulate scenarios under conditions which are not feasible to conduct experimentally. An iterative process of customized simulations, rather than traditionally used empirical observations, will provide insight regarding in-vivo mechanical responses. This quantitative data of degrading PLG 10-90 will help determine the viability of the copolymer for ACL reconstruction.