Mechanical Properties of Articular Cartilage

Compressive cartilage properties have often been examined using creep indentation, confined compression or free/unconfined compression methods. Indentation techniques permit in situ testing without the necessity of 

Femoral head Unrelaxed (initial) Creep modulus (indentation) 1.9-14.4 m 

Tibial plateau Young s Modulus (confined compression) 5.1-7.9 [91 

Patella Relaxed (equilibrium) Aggregate modulus (Indentation) 0.3-0.6 [41 

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The remarkable mechanical properties of articular cartilage result from the structure of collagen and proteoglycans, and from the properties of the fibrous composite formed by the interactions of collagen and proteoglycans in intercellular matrix. 

Keinpson, G.E. Mechanical Properties of Articular Cartilage, "Adult Articular Cartilage" Edited by M.A.R. Freeman,... 

Kempson, G. (1979) Mechanical properties of articular cartilage. In Adult Articular Cartilage, 2nd ed.. Freeman M.A.R., Editor, Pitman Medical Publishing Co. Ltd., Kent, England, pp. 333-414. 

The overall structure of articular cartilage is analogous to a jelly-filled balloon. The PG-rich middle zone is osmotically pressurized, with fluid restrained from exiting the tissue by the dense coUagen network of the superficial zone and the calcified structure of the deep bone. The interaction between the mechanical loading forces and osmotic forces yields the complex material properties of articular cartilage. 

Biocompatibility and Mechanical Properties. Currently, their are no suitable artificial materials for the prosthetic replacement of articular cartilage. The biocompatibility is considered the primary criterion in the selection of such a material. In a recent study, Furst and co-workers(10) compared the biocompatibility of the polyurethane to the well known medical grade silicone polymer. The tissue reactions to small polymer discs, inserted in an articulating space—the suprapatellar bursa of rabbits, was examined. The foreign body reaction of the tissue at the implantation site was evaluated at intervals of 7 days,... 

Compatibility and Mechanical Properties of a Candidate for Articular Cartilage Replacement, Trans, of the 4th Annual Meeting Society of Biomaterials, 1978, 2, 159. ... 

Guilak, F., Jones, W.R., Ting-Beall, H.P., Lee, G.M. The deformation behavior and mechanical properties of chondrocytes in articular cartilage. Osteoarth. CartU. 7, 59-70 (1999)... 

Armstrong, C. and Mow, V.C. (1982) Variations in the intrinsic mechanical properties of human articular cartilage with age, degeneration and water content. J. Bone Joint Surg., 64A, 88-94. 

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