The research focus of orthopedic surgery during the past few years has shifted from its traditional mechanical emphasis to the biologic basis for the growth, development, and repair of musculoskeletal tissues. New technologies offer investigators previously unavailable tools for studying and manipulating the physiological cascade of cellular and chemical events responsible for bone and cartilage healing.
A host of different proteins from the transforming growth factor β (TGF-β) superfamily have been found to induce bone repair by stimulating the phenotypic expression of undifferentiated mesenchymal cells.1 One such protein, bone morphogenetic protein 2 (produced by recombinant technology), was found to be as effective as autogenous bone graft in healing of a 2.5-cm femoral defect in a sheep model.2 Similar stimulatory effects of various local growth factors on the healing of critical-sized defects have been documented in other animal models.3 Even more promising is the apparent effect of these
Bucholz RW, Buckwalter JA. Orthopedic Surgery. JAMA. 1996;275(23):1836-1837. doi:10.1001/jama.1996.03530470064038