ANATOMY OF THE SPINE
The human spine is formed by individual vertebrae and connective tissue discs in between. The vertebrae form the spinal canal. There are seven cervical, twelve thoracic, and five lumbar vertebrae. The intervertebral discs are the link between the individual vertebral bodies.
Normal anatomy of the spine. Longitudinal section and cross sections through the cervical, thoracic and lumbar spine.
The little joints that link the vertebrae together are known as facet joints. They help to stabilize the spine and, together with the intervertebral discs, allow a certain degree of mobility of the spinal cord. The spinal canal should be wide enough to allow nerve roots to float freely in cerebrospinal fluid.
The front border of the spinal canal is built by the vertebral bodies and intervertebral discs, the side by the intervertebral joints (facets) and back by the ligamentum flavum (yellow band) and vertebral arches. Discs consist of an outer fibrous ring (annulus fibrosus), which surrounds an inner gel-like center (nucleus pulposus).
The spinal cord and nerve roots lie within the spinal canal. The spinal cord extends downwards approx. to the 1st lumbar vertebra. Below, only nerve roots are present in the spinal canal. At the level of the intervertebral disc the nerve roots pass through the neural root foramina to exit the spinal canal. The spinal cord and nerve roots conduct electric-like signals from the skin and joints to the brain, and process of movement is initiated from the brain to the muscles.
Spina bifida is a birth defect due to failed closure of the neural tube. The neural tube is the embryonic structure that eventually forms the brain, spinal cord and their protective sheets. Normally, the neural tube forms early in the pregnancy and closes by the first month after conception. There are four types of spina bifida: occulta, closed neural tube defects, meningocele, and myelomeningocele.
CAUSE OF SYMPTOMS
Congenital malformation of the nerve roots and spinal cord
SYMPTOMS AND SIGNS
Depending on the nature, location and size of the spina bifida defect, symptoms can be severe or completely absent.
Symptoms may include
Complete/partial paralysis and numbness of the feet
Urinary incontinence or retention
THE DIAGNOSIS IS BASED ON Medical history Clinical exam
Second trimester (16-18 weeks of gestation) maternal serum alpha-fetoprotein screening Еchography Magnetic resonance imaging (MRI)
Treatment depends on the type and severity of the spina bifida present. learn more ...