Naturally occurring extracellular matrix as a scaffold for musculoskeletalrepair

The use of naturally occurring extracellular matrix materials as scaffolds for the repair and regeneration of tissues is receiving increased attention . The present study evaluates the use of the extracellular matrix derived f rom porcine small intestinal submucosa as a scaffold for anterior cruciate ligament replacement in a goat model, Sixty healthy adult female goats were divided into two equal groups of 30 each. The right anterior cruciate liga ment of each goat was removed surgically and replaced with either a patella r tendon autograft or a small intestinal submucosa anterior cruciate ligame nt scaffold. Three animals from each group were sacrificed at 6 weeks, 3 mo nths, 6 months, and 1 year after surgery and grafts were harvested for hist opathologic examination. Six animals from each group were sacrificed immedi ately after surgery, 3 months, and 1 year after surgery and the grafts were harvested for biomechanical testing. There was no evidence for an adverse clinical response to the xenogeneic small intestinal submucosa scaffold. An terior drawer values were not different between the two groups at any point , The failure force of the patellar tendon autograft increased from 253 N a t Time 0 to 879 N at 12 months. The failure force for the small intestinal submucosa repair device was 721 N at Time 0, decreased to 293 N at 3 months , followed by an increase to 706 N at 12 months. Histopathologic analysis s howed a mixed inflammatory cell presence within the small intestinal submuc osa scaffold including macrophages and lymphocytes in the early months afte r surgery. The inflammatory cells disappeared in the later stages of remode ling and the histologic appearance of the small intestinal submucosa remode led grafts and the patellar tendon autografts were indistinguishable at 12 months. Xenogeneic small intestinal submucosa holds promise as a resorbable bio-scaffold for anterior cruciate ligament repair in the goat model.