Cartilage Mechanics

Novel Synthetic Biolubricant Reduces Friction in Previously-Worn Cartilage Evaluated by Long-Duration Torsional Friction Test

During osteoarthritis (OA), the lubricity of synovial fluid (SF) decreases. Therefore, we synthesized a novel, 2MDa polymer biolubricant (“2M TEG”) designed to augment the lubricating properties of SF in OA. This study’s aims were 1) to compare the abilities of 2M TEG and bovine synovial fluid (BSF) to reduce the coefficient of friction (COF) for previously “worn” cartilage specimens during a long-duration, torsional, wear test, and 2) using the same regimen, examine the “reversibility” of 2M TEG’s lubricity relative to BSF. For both aims, each wear test consisted of subjecting mated, bovine osteochondral plug pairs to 10,080 rotations. To accomplish Aim 1, plug pairs were subjected to three sequential wear regimens (Wear 1-3). Wear 1&2 were used to progressively “wear” the cartilage, and Wear 3 was used to test the efficacy of either BSF (n=4) or 2M TEG (n=4) on “worn” cartilage. For Aim 2, three pairs were subjected to four sequential wear regimens, where the lubricants were BSF, BSF, 2M TEG, and BSF, respectively. The relative percent reduction in COF between Wear 3 and Wear 2 in Aim 1 was greatest for 2M TEG, followed by BSF. For Aim 2, the mean percent reduction in COF for Wear 3 relative to Wear 2 was almost exactly the same as the mean increase in COF for Wear 4 relative to Wear 3. By reducing the COF for worn cartilage in OA joints, synthetic biolubricants such as 2M TEG could help minimize further cartilage wear and ameliorate the progression of OA.
Listed In: Biomechanical Engineering, Biomechanics, Biotribology, Orthopedic Research