Spinal dysraphism is a congenital defect of the neural tube, the structure that precedes the development of the spinal cord in fetuses. In normal development, the neural tube folds together precisely to form the spinal column and secure the spinal cord. Problems can arise if the neural tube never fully closes or seals together incorrectly. Symptoms in infants and growing children can range from very mild and almost unnoticeable to debilitating and disfiguring. Depending on the severity of symptoms, a multifaceted treatment plan involving medication, surgery, and physical therapy may be needed to promote proper growth and development.
Open spinal dysraphism occurs when the neural tube fails to close completely. There are a few different varieties of open spinal dysraphism, the most common of which is the development of a meningocele in the lower or middle back. A meningocele is basically an opening in the spinal column from which membranes, cartilage, and cerebrospinal fluid escape. The spinal cord is usually kept intact in the presence of a meningocele, so it can continue to develop without major complications to central nervous system functioning.
A less common but much more serious complication of open spinal dysraphism is the growth of a myelomeningocele. A large cap in the spinal column leaves room for a membrane-lined sac to protrude outward, breaking through skin and muscle tissue. The myelomeningocele sac can contain cartilage, cerebrospinal fluid, and bits of the spinal cord and nerve endings. The condition can severely impair future development and central nervous system functioning. An infant may not have control over motor movements or bladder and bowel functions. Disabling leg weakness or even permanent paralysis can occur in extreme cases.
In most cases, open spinal dysraphism can be diagnosed while the fetus is still in the womb. Ultrasounds and blood tests can reveal abnormalities in spinal development in the second or third trimester. A baby born with open spinal dysraphism typically needs to undergo immediate surgery to try to realign the spinal cord and vertebrae. A shunt may need to be placed in the brain to drain excess cerebrospinal fluid into the abdominal cavity. Ongoing physical therapy, medications to control pain, and follow-up cosmetic surgical procedures may be needed throughout a patient's lifetime.
Spinal dysraphism can also be a more subtle problem where the neural tube almost closes correctly and the internal structures do not protrude from the spinal column. Spina bifida occulta is the most common form of closed spinal dysraphism, and it may or may not cause physical symptoms and health complications. Most children who are born with spina bifida occulta develop normally despite minor defects and they do not need special treatment. Occasionally, there may be an indentation in the lower spine that is prone to excessive hair growth. Patients may be at risk of complications later in life, such as scoliosis, difficulty bending or twisting, and herniated disks that may require surgical intervention.