Towards bio-mimetics of the anterior cruciate ligament using collagen fiber reinforced bio-composites
Raz Agron1,2, Amir Dolev3, Mustafa Yassin3, Rami Haj-Ali2 and Mirit Sharabi1
(1) The department of Mechanical engineering and Mechatronics, Ariel University, Ariel, Israel
(2) School of Mechanical Engineering, Tel Aviv University, Tel Aviv, Israel
(3) Department of Orthopedic Surgery, Ha’Sharon Hospital, Petah Tikva, Israel
The Anterior Cruciate Ligament (ACL) is one of the four knee ligaments responsible for the stability of the joint. Although there are approximately 37 ACL related surgeries the for every 100,000 people each year1, proper ACL repair is not available to date. Since the use of “Gold Standard” autografts solutions available today (i.e. patellar tendon, hamstring tendon etc.) can result in a deficiency in knee joint function2-3, a need arises for the design of a biocompatible implant that can mimic the native mechanical behavior of the ACL.
From a mechanical standpoint, the ACL is a composite material, composed of stiff collagen fibers embedded in proteoglycans matrix providing nonlinear behavior with large deformations. Our research aims to mimic that mechanical behavior by fabricating a collagen fiber reinforced biocomposite4 ACL implant. Extracted from soft corals, our ultra-long collagen fibers are arranged unidirectionally and embedded in an alginate hydrogel to mimic the structure of the native ACL. The mechanical behavior of the bio-composite ACL is compared experimentally with the tensile behavior of native human ACL specimens and 3D hyperelastic finite element knee model.
Our goal is to understand the effects of the ACL’s structure on its mechanical behavior under physiological loading and eventually mimic it using our biocomposites, in order to enable efficient ACL repair and replacement.
References:
1. Gianotti, S. et al. Journal of science and medicine in sports 12, 622-627 (2009).
2. Gollquist, J. & Messner, K. Sports Med 27, 143-156 (1999)
3. Stefan, L. et al. The American Journal of Sports Medicine 35, 1756-1769 (2007)
4. Sharabi, M. et al. Journal of the Mechanical Behavior of Biomedical Materials 36, 71-81 (2014).
