Biologic Scaffold Remodeling in a Dog Model of Complex Musculoskeletal Injury

• Published in: The Journal of surgical research Vol. 176; no. 2; pp. 490 - 502
• Main Authors: Turner, Neill J., B.Sc., Ph.D, Badylak, John S., M.D, Weber, Douglas J., Ph.D, Badylak, Stephen F., D.V.M., Ph.D., M.D
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.08.2012
• Subjects: Action Potentials - physiology; Animals; Cartilage - physiology; constructive remodeling; Disease Models, Animal; Dogs; Electromyography; extracellular matrix; Extracellular Matrix - physiology; Extracellular Matrix - transplantation; Female; Femur - physiology; Intestinal Mucosa - physiology; Intestinal Mucosa - transplantation; Muscle Contraction - physiology; muscle injury; Musculoskeletal Diseases - surgery; quadriceps; Quadriceps Muscle - injuries; Quadriceps Muscle - physiology; Quadriceps Muscle - surgery; Regeneration - physiology; skeletal muscle; Surgery; Swine; Tendon Injuries - physiopathology; Tendon Injuries - surgery; Tissue Scaffolds; Transplantation, Heterologous; muscle injury; quadriceps; constructive remodeling; skeletal muscle; extracellular matrix
• ISSN: 0022-4804; 1095-8673
• DOI: 10.1016/j.jss.2011.11.1029

Background Current treatment principles for muscle injuries with volumetric loss have been largely derived from empirical observations. Differences in severity or anatomic location have determinant effects on the tissue remodeling outcome. Biologic scaffolds composed of extracellular matrix (ECM) have been successfully used to restore vascularized, innervated, and contractile skeletal muscle in animal models but limited anatomic locations have been evaluated. The aim of this study was to determine the ability of a xenogeneic ECM scaffold to restore functional skeletal muscle in a canine model of a complex quadriceps injury involving bone, tendon, and muscle. Materials and Methods Sixteen dogs were subjected to unilateral resection of the distal third of the vastus lateralis and medial half of the distal third of the vastus medialis muscles including the proximal half of their associated quadriceps tendon. This defect was replaced with a biologic scaffold composed of small intestinal submucosa extracellular matrix (SIS-ECM) and the remodeling response was evaluated at 1, 2, 3, and 6 mo ( N = 4 per group). Results The initial remodeling process followed a similar pattern to other studies of ECM-mediated muscle repair with rapid vascularization and migration of myoblasts into the defect site. However, over time the remodeling response resulted in the formation of dense collagenous tissue with islands of muscle in the segments of the scaffold not in contact with bone, and foci of bone and cartilage in the segments that were adjacent to the underlying bone. Conclusions SIS-ECM was not successful at restoring functional muscle tissue in this model. However, the results also suggest that SIS-ECM may have potential to promote integration of soft and boney tissues when implanted in close apposition to bone.