EC Orthopaedics

Because articular cartilage heals poorly, restoring damaged knee cartilage remains clinically difficult. Established non-cell-based procedures, including microfracture and mosaicplasty, frequently produce repair tissue with limited mechanical competence, dura- bility, and integration. More advanced strategies, such as autologous chondrocyte implantation and stem-cell-based approaches, have their own limitations, notably loss of cells from the target site and nonuniform cell distribution. Sustained localization of therapeutic biological material is essential to the success of these treatments. Achieving reliable union between the implant and intact neighbor- ing cartilage, however, remains unresolved, particularly when bone-marrow-derived products or autologous adipose tissue are used. We investigated a viscogel intended for cartilage restoration, with particular attention to its adhesive behavior, tissue integration, and regenerative potential. The formulation demonstrated substantial adhesive strength and exceeded the performance reported for commercially available alternatives such as fibrin sealants. Adhesion and long-term incorporation were examined in vivo in full-thickness caprine cartilage defects over a six-month period. Acellular viscogel treatment produced better continuity with adjacent tissue and more extensive repair than the untreated condition. A uniform intra-articular distribution was observed after infrapatellar administration and after medial or lateral knee approaches. Complementary in vitro experiments showed that cells remained highly viable after encapsulation, were distributed successfully throughout the viscogel, and generated abundant matrix. Together, these observations support adhesive viscogels as delivery matri- ces capable of strengthening cell-based treatment strategies for knee cartilage injury.

Keywords: Adhesive Viscogel; Articular Cartilage; Tissue Integration; Cartilage Repair

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