If spinal convergence is not complete, a part of the meninges (meningocele) and/or the spinal cord (meningomyelitis) may be left unprotected and uncovered in the back. This condition is called spina bifida and has different grades, depending on the type of tissue missing. It is a condition that is usually surgically corrected immediately after birth and must have been detected by ultrasound during pregnancy. It is often associated with loss of cerebrospinal fluid, or hydrocephalus. If not treated in a timely manner, there can be serious neurological consequences or infection.
In other cases, even with complete central neural tube closure, there may be other problems, such as congenital dermoid cysts and fistulas, which predispose for types of meningitis and other infections, and usually require surgical repair. There are also disorders of the spinal cord itself (diastematomyelia) or the spinal cord sheaths (neurenteric cysts) or the ligament that holds the spinal cord at the base of the spine (tethered spinal cord). The earlier these conditions are diagnosed, the more effective the treatment (usually surgical intervention).