Orthopedic surgical intervention may be indicated for patients with a variety of musculoskeletal problems associated with myelomeningocele.

Spinal deformities are common, and progressive spine curving or scoliosis may lead to decline in functional status, as well as increased risk for development of pressure sores and potential cardiopulmonary compromise. Spinal stabilization is necessary to correct curving, which may be related to congenital vertebral malformation or may be a result of the collapsing spine in high-thoracic paraplegia. Paralytic scoliosis develops in 40-60% of children with spinal deformities caused by myelomeningocele and may be the result of asymmetric muscle forces, unilateral hip dislocation and pelvic obliquity, or an underlying progressive neurological process such as syringohydromyelia. Intervention to introduce use of orthotic devices may serve as a temporary measure, but growing children with spinal curves greater than 30-35° require surgical fusion (Sandler, 1997).

Muscle imbalance around the hip joints may lead to progressive hip dislocation, which typically occurs in early childhood in patients with high- and mid-lumbar lesions and in late childhood or adolescence in children with low-lumbar lesions. The literature evaluating the benefits of surgical relocation of hips reflects ongoing controversy surrounding the topic. For bilaterally dislocated hips, questionable functional benefit of surgery exists for patients with L3 and L4 lesions. Surgery for unilateral dislocation of the hip may not be required for patients who are non-ambulatory or have high-level lesions.

Common knee deformities include flexion and extension contractures, usually related to a capsular contracture. Surgery is indicated when the contracture causes a functional problem. Types of surgery include a simple tenotomy of the knee flexor tendons in the child with a high-level lesion or lengthening of the tendons in the child with a low lumbar or sacral-level lesion, for whom preservation of hamstring function is important. Extension contractures are less common, but they interfere with sitting and are associated with hip dislocation and clubfoot. If the contracture is not amenable to conservative measures (e.g., serial casting), an extensor tendon release is performed.

Foot and ankle deformities may cause skin breakdown, prevent the patient from wearing shoes, and compromise ambulation. In the case of clubfoot, most patients need surgical correction in the first year of life, usually involving multiple soft tissue release procedures with tendon excisions. In older children, other types of deformities (e.g., adduction, calcaneovarus, and calcaneovalgus) may require muscle tendon transfer, to decrease the paralytic muscle imbalances and achieve a foot that can tolerate a brace. Triple arthrodesis fusion rarely is indicated but may be necessary in cases of ankle instability (Brown, 2001).