Lower Limb Deformity Caused by Spina Bifida Sequelae and Tethered Cord Syndrome

Abstract

Spinal bifida is a posterior spinal canal defect caused by the developmental disorder of the ossification center of the posterior spinal arch during embryonic development. The patient presents with the swelling at the back due to herniation of spinal canal contents. The causes may be due to having fever during pregnancy and deficiency of folic acid in early pregnancy. Some scholars have reported that they may be related to genetic factors.

According to Qinsihe orthopedic database, more than 90% of the spina bifida occurred in the lumbosacral region as it is a pivot joint and a weak part during body development which plays an important role in that the four-legged walking animal is evolved into a human being with two legs, walking upright.

The adhesion or thickening of the spinal cord results in different grades of paralysis of the lower limbs, joint contracture, and imbalance of muscle strength, which in turn cause the disorders and deformities of hip, knee, foot, and ankle joints in accordance with the patient’s age. The numbness of the skin in different parts can also cause the formation of ulcers and hemorrhoids, and the neuropathy of the anorectal nerves can cause different deformities and dysfunction of the recto-urinary system.

Lower limb deformity and disability with spina bifida are difficult to be classified in the current orthopedic subdiscipline, and the rate of misdiagnosis and mistreatment is high. Therefore, for a child with deformed feet, lumbosacral imaging is routinely performed to determine whether it is caused by spina bifida or other space-occupying lesions in the spinal canal. If it is indeed caused by spina bifida, the experienced neurosurgeon should be consulted. It is recommended to perform tethered cord surgery first, which can avoid or reduce the strain on the nerve growth.

In 2 years after the lumbosacral neurolysis, whether the nerve can be repaired or not has been confirmed. It is the right time for correcting the foot and ankle deformities. In a clubfoot case with ankle muscle imbalance, simple dynamic balance surgery should be performed early. Otherwise, deformed bone changes are likely to occur. The progress speed of valgus foot and claw foot deformity is relatively slow, so the operation can be suspended or delayed.

The types of foot and ankle deformities are diverse. The age and gender of the patient are different. The degree of deformity and sensory disturbance are different. Some patients have spinal, hip, knee deformity, and defecation dysfunction. As there is a variety of clinical manifestations, currently, various high-tech examinations and equipment do not play a decisive role in the treatment of such ankle deformities. The experience, wisdom, dialectical thinking, overall awareness, and systematic evaluation of orthopedic surgeons can be required to develop a reasonable treatment plan individually.

The surgical strategy basically follows the principle of treatment of poliomyelitis sequelae, that is, to correct deformity, balance muscle strength, stabilize joints, and restore normal load bearing sole. Patients with skin dysfunction should be treated with external fixators postoperatively. When a bone surgery is performed to correct a deformity in patients with sensory disorder, it is necessary to retain a certain degree of foot flexibility as the stiff foot is prone to pressure ulcers in the weight-bearing area.

The Qinsihe orthopedic method of foot and ankle surgery combined with Ilizarov external fixation technique for the treatment of limb deformity of spina bifida sequelae can obtain satisfactory results, including a large number of foot and ankle deformities with skin ulcers, who were advised amputation, were saved.