Approximately 18.5% of fractures in children involve the growth plate. Physeal fractures often heal by formation of a bony bar, leading to angular deformity and limb-length inequality.
Several attempts have been made to prevent partial growth plate closure and promote repair. Current clinical treatment involves resection of the osseous bridge followed by replacement with “interpositional” materials, such as bone wax, beeswax, poly(methyl methacrylate), siliconized Dacron, silicone rubber, and grafts of fat and cartilage. All these treatment have inadequacies, leaving approximately 50% of patients with continuing deformities (Clin Orthop Relat Res 405: 242, 2002; J Pediatr Orthop, 22: 565, 2002). Currently, there is no treatment for growth plate injury that leads to complete regeneration of the damaged tissue.
Experimental tissue engineering via scaffolds has been explored for stabilization and regeneration of growth plate. Scaffolds with and without mesenchymal stem cells have been studied. However, these in vitro tissue engineering approaches require harvesting of cells from the patient and thus two procedures.
Our goal is to develop biodegradable polymeric systems that can direct native pluripotent mesenchymal cells to appropriate lineage allocation by controlled delivery of IGF-I protein or plasmid encoding IGF-I.