Effective lubrication of articular cartilage by an amphiphilic hyaluronic acid derivative

• Published in: Clinical biomechanics (Bristol) Vol. 27; no. 5; pp. 515 - 519
• Main Authors: Schiavinato, Antonella, Whiteside, Robert A
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.06.2012
• Subjects: Animals; Cartilage; Cartilage, Articular - chemistry; Cattle; Friction; Hyaluronan; Hyaluronic acid; Hyaluronic Acid - analogs & derivatives; Hyaluronic Acid - chemistry; Hydrophobic and Hydrophilic Interactions; In Vitro Techniques; Lubricant; Lubrication; Osteoarthritis; Physical Medicine and Rehabilitation; Cartilage; Hyaluronan; Hyaluronic acid; Osteoarthritis; Lubricant
• ISSN: 0268-0033; 1879-1271
• DOI: 10.1016/j.clinbiomech.2011.11.012

Abstract Background Intra-articular injection of hyaluronic acid based therapies is gaining popularity as a treatment option for non-operative management of patients with symptomatic osteoarthritis. Although there is an abundance of evidence for both biological and mechanical mechanisms of joint protection by hyaluronic acid, one clear intention of viscosupplementation is to reduce friction and wear by providing an extrinsic lubricant. We tested the in vitro friction response of a novel hyaluronic acid derivative that presents amphiphilic features to promote adhesion to the cartilage surface and thereby improve cartilage lubrication. Methods Migrating Contact Area and Static Contact Area friction tests were conducted on bovine articular cartilage to assess the efficacy of two lubricants, a chemically modified amphiphilic hyaluronic acid and synovial fluid from a healthy joint, as well as a phosphate buffered saline negative control. Findings No differences in lubrication ( P = 0.34) were evident between the three test articles during the Migrating Contact Area test, which represents articulation of healthy articular cartilage. The modified hyaluronic acid presented an equilibrium friction coefficient 2.8 times less than that of the synovial fluid ( P ≤ 0.0005) and five times less than that of the PBS control ( P ≤ 0.0001) during the Static Contact Area test, representing a mixed lubrication condition. Interpretation The present study demonstrated that a chemically modified amphiphilic hyaluronic acid can provide equivalent lubrication to synovial fluid during articulation of loaded healthy articular cartilage and can provide superior lubrication as indicated by a lower coefficient of friction than synovial fluid under loading conditions potentially associated with cartilage wear.