Developmental Biology in Orthopaedics

Abstract

During normal fetal development, a variety of cell-signaling pathways are regulated in a coordinated manner so that cells can proliferate, move, and even die off in an organized fashion that allows organs to develop. Over the past decade, there have been tremendous advances in understanding how the musculoskeletal system develops. Knowledge about these pathways and how they regulate cell behavior can be applied to musculoskeletal pathologic conditions and repair processes. Many of the pathways that are important in development can be targeted therapeutically; interestingly, many such agents have been identified by their teratologic potential. Identifying the role of these key signaling pathways in musculoskeletal disorders carries strong potential to rapidly identify new therapeutic approaches. Genetically modified organisms, such as transgenic mice, are important tools in this work. Because these organisms have genetic abnormalities from the start of development, they can be used to study the role of genes or cell-signaling pathways both in development and in pathologic and repair processes that occur in maturity. A symposium sponsored by the American Academy of Orthopaedic Surgeons, the Orthopaedic Research and Education Foundation, the Orthopaedic Research Society, the National Institutes of Health, the Canadian Institutes of Health Research, the Shriners Hospitals for Children, Kyphon, and Stryker, on developmental biology in orthopaedics, was held in Toronto in October 2006 to review the state of the art in developmental biology of the musculoskeletal system, determine how this information could be applied to disorders treated by orthopaedists, and foster greater collaboration between orthopaedic investigators and developmental biology researchers. The participants also identified several areas of focus for future research that they thought would have particularly fruitful potential. Development begins with fertilization of the ovum; this fertilized cell is called a zygote. The zygote undergoes rapid mitotic divisions and cellular differentiation, leading to the development of a …