Pediatric Orthopedics

Myelomeningocele (Spina Bifida)

Myelomeningocele (Spina Bifida)

Myelomeningocele ( spina bifida ) is a developmental birth defect of neural tube. Neural tube is an embryonic structure develops into  brain and spinal column. ın this malformation, the posterior parts of spinal colon stays open . It could be minor opening in the backbone as in spina bifida occulta or it could be a big sac containing spinal cord/nerves and spinal fluid.

which part of the spinal column is involved in the disease?

Myelomeningocele  while is more common in  lumbar and sacral parts of the spine, it cane seen in any part of the spine.

How frequently is myelomeningocele  seen?

Myelomeningocele is seen 1-4 in 1000.

What causes Myelomeningocele?

the cause of the disease is unknown. While parents who have a child with myelomeningocele have an increased risk for their future children, a genetic trait has not been shown yet. Also, low levels of folic acid in women prior and during the pregnancy may have a higher risk of having a baby with birth defect. That is why folic acid supplements are recommended for women who plan to have a child.

Diagnosis

Screening tests may be helpful. Advanced fetal ultrasonography is diagnostic. It is very rare to make the diagnosis at birth in today’s developed medicine.

Symptoms

Patients with the malformation will have an open area of a fluid filled sac on the back. Children with the deformity may have hydrocephalus, loss of bowel and bladder control, paralysis and sensation deficits in legs, additional lower extremity deformities such as clubfoot, vertical talus. The severity of the involvement is related with the level of myelomeningocele. The upper is the myelomeningocele level, the severer is the deformity.

Treatment

The first step should be closure of the sac on the back. This surgery is needed to be done within 24-48 hours. The comments orthopaedic problems are kyphosis and kypho-scoliosis seen due to the posterior defects of the spinal column. These deformities  may affect the daily functions and may also cause respiratory and heart problems. Anterior column resection and long fusions are used in the treatment. The vertebral surgery is performed over 3 years of age. 30-50 % of myelodysplasia patients develop kyphosis and kyphosis-scoliosis. Vertebral problems may be seen not onlydue  to the birth defects but also secondary to the unilateral hip dislocations, pelvic obliquity, and tethered cord, etc. The orthotic treatment of scoliosis is not successful in myelomeningocele the deformities over 45-50 degrees are treated best with surgery.

Hip problems are common in myelodysplasia too. Upper and mid lombar level myelo patients develop hip dislocation secondary to the paralytic hip muscles in early childhood versus lower lumbar levels in late childhood and adolescent years. The treatment of the hip dislocation in lumbar level myelodysplasia patients should not aim to reduce the hip since reduction is not successful in this level myeleodysplasia. One can perform hip surgery t-o release the contractions to make the hip more mobil. Hip dysplasia patients with sacral level spina bifida need and benefit hip reducing surgeries.

Some patients may present with knee flexion contracture which can be treated successfully by release of posterior capsule and tendons. Patients may have altus deformity in the knee and ankle. Orthotic treatment is applied by the age of 5 years old. If unsuccessful by then proper surgical treatment can be performed.

tethered cord, spina bifida, myelomeningocele

 

About the author

Prof.Dr. Seref Aktas