Spina bifida occulta is a neural tube defect that causes a deformity in one or more of the vertebrae, which are small bones that form the spinal column. Depending on the location and severity of the deformity, this condition can affect the legs and back and result in bladder or bowel incontinence. Spina bifida occulta can also cause abnormalities on the layer of skin that lies above the deformity.
Spinal Cord Defects
According to the Spina Bifida Association of America, spina bifida occulta can cause several spinal cord defects. Tethered cord is when the spinal cord is attached abnormally to surrounding structures, which causes stretching or damage. Thickened filum terminale is a thickening of the end section of the spinal cord. Fatty filum terminale is a fatty lump inside the end section of the spinal cord. Split spinal cord, also called diastematomyelia, is when the spinal cord is split in two.
Pain & Weakness
The Australian Spina Bifida & Hydrocephalus Association lists pain and weakness as two effects of spina bifida occulta. This is because the nerve roots are affected at the location of the spinal deformity. Weakness can occur in the legs and back, making walking and other physical activities more difficult. Back pain is common in people with spina bifida occulta and may be more severe in cases where tethered spinal cord and other spinal defects exist.
Changes in Sensation
According to the Spina Bifida Association of America, spina bifida occulta can cause numbness, tingling and loss of sensation in the back or legs. This is because the spinal deformity can affect the nerve roots. If the deformity is severe and the nerve roots are severely affected, people with spina bifida may lose feeling in their legs or at the bottoms of their feet.
Orthopedic Deformities
Deformities of the feet, legs and back may occur as a result of spina bifida occulta. According to the National Institute of Neurological Disorders and Stroke, people with spina bifida occulta may require the use of braces, crutches or wheelchairs because of these deformities. Scoliosis, which is a curved spine, may also be the result of spina bifida occulta.
Incontinence
Damage to the nerve roots in the spinal column can lead to bowel or bladder incontinence in people with spina bifida occulta. The Australian Spina Bifida & Hydrocephalus Association lists bedwetting, dribbling of urine, recurrent urinary tract infections, constipation and a lack of awareness of the need to urinate until the urge is intense as indicators of problems with continence.
Skin Abnormalities
According to the Spina Bifida Association of America, the skin that lies above the spinal deformity may have defects indicating that spina bifida occulta is present. These skin defects include a hairy patch, fatty lump, purplish spot, dark spot, deep pimple or area of skin with a decrease in pigmentation. People with these skin defects may be evaluated with ultrasound or MRI to determine if spina bifida occulta is the cause.
