Mechanical Loading Reduces Chondrocyte Death After Single Impact Trauma: Porcine Knee Model

Osteoarthritis often results from degenerative changes induced by trauma such as joint impact injuries sustained during athletics, combat, or motor vehicle accidents. Articular cartilage, avascular in nature, relies of synovial nutrition [1] and lacks sufficient regenerative capabilities [2]. Acute cartilage injuries have been shown to induce cell death [3, 4, 5], leading to reduced chondrocyte density and degenerative changes to the cartilage matrix composition; over time the tissue becomes compromised and loses its ability to maintain and restore itself. It has been demonstrated, that mechanical loading can affect local perfusion and diffusion through the matrix thereby altering the flow of nutrients and metabolites [2, 6]. Furthermore, mechanical loading modulates the chondrocyte biosynthesis of extracellular matrix that is required in the cartilage repair process. In this study, a two part in-vitro porcine knee model was utilized to investigate articular cartilage response immediately following a single impact injury under cyclic mechanical loading conditions.