Growth and Maturation of the Spine from Birth to Adolescence

Abstract

Normal development of the spine, from birth, includes the progressive longitudinal and axial growth of an osseous spinal column that allows a neuroprotective mechanical axis for all motion throughout life. Growth of the spinal column may become eccentric during life and can result in spinal deformity. In the developing spinal column, there exist four general features that permit the successful growth of the human spine: 1. Osseous development is essential for the provision of a mechanical axis for the appendicular skeleton as well as an axis for muscular development. This axial skeleton has features that are unique to all mammalian bipeds. 2. Characteristic curves in the osseous spinal column need to develop once the child begins to sit upright and eventually walk. Lordotic cervical and lumbar segments begin to develop, and the development of kyphotic thoracic and sacral segments permits balance in the sagittal plane. 3. Continuous symmetric growth of the spinal column must occur while the child develops. Both longitudinal (vertical) and latitudinal (axial) growth must occur, and an eccentric growth in either direction can result in a spinal deformity. 4. Neural element protection remains highly important throughout development and in adult life. The developing osseous spinal column must also permit safe exit of all nerve roots. The spinal cord, as well as the osseous column around it, continues to lengthen. A variation in growth rates can occur, which may result in neurologic deficits and spinal column deformity (e.g., tethering of the cord and syringomyelia). In the early embryonic stage, the spinal cord extends to the end of the osseous column, and then, when the crown-rump length of the fetus is 120 mm, it ascends to the third or fourth lumbar vertebra1. A more gradual ascent then occurs, with the conus medullaris ending at the level of the first or second …