What is Spondyloepiphyseal Dysplasia?

Spondyloepiphyseal dysplasia, also known as spondyloepiphyseal dysplasia congenita (SEDC), is a rare genetic condition that adversely impairs spinal formation in utero and inhibits bone growth, creating a deficiency that leads to dwarfism. Individuals affected by spondyloepiphyseal dysplasia may also experience additional conditions that include impaired vision, decreased muscle tone, and curvature of the spine. Treatment for SEDC generally centers on alleviating symptoms associated with complications rather than increasing stature.

Considered the most frequent cause for the development of disproportionate dwarfism, SEDC generally affects physical development only and does not impair one’s intellectual or cognitive abilities. Individuals with SEDC generally have a large head in proportion to their body, a trunk of average size, and shortened limbs. In some cases, those with SEDC may have a short trunk and limbs that are small, yet considered large in proportion to the rest of their body. There are several signs and symptoms an individual with SEDC may exhibit.

An average adult with spondyloepiphyseal dysplasia usually matures to a height of just over four feet. Abnormal bone development as characterized by flattened cheekbones, hip deformities causing an inward curvature of the thigh bones, and progressive kyphoscoliosis, or a curvature of the upper spine are common signs associated with spondyloepiphyseal dysplasia. Additional characteristics of this disorder may include clubfeet, average size feet and hands, and impaired sensory perception associated with hearing and sight.

A diagnosis of spondyloepiphyseal dysplasia is generally made during early childhood. During routine examinations, the child’s height, head circumference, and weight are recorded and plotted on a chart utilized to rank proper development milestones. If the child’s development appears to be delayed or is disproportionate, the pediatrician may request that more frequent measurements be taken to closely monitor the child’s development. When a pediatrician suspects that the child has SEDC, he or she may refer the child to other pediatricians whose specialties include genetic conditions and bone abnormalities. In order to rule out the presence of any secondary conditions, genetic tests may be performed, and magnetic resonance imaging (MRI) or X-ray may be used to determine the location and extent of any delayed or impaired bone development.

There are a variety of corrective surgical procedures that may be utilized to alleviate symptoms associated with SEDC. Procedures such as the implantation of growth plates, limb straightening, the utilization of rods to correct spinal curvature, and alleviating spinal cord pressure by altering vertebrae formation are commonly performed. Some individuals may undergo a limb-lengthening procedure that involves the division of longer bones into sections. Metal poles, or scaffolding, are introduced between the sections of bone and held in place with screws and pins that allow additional room for the bone to grow together, making it longer.

Children with spondyloepiphyseal dysplasia should be provided with adequate head, neck, and back support when sitting to promote good posture. Individuals with SEDC are encouraged to pursue healthy activities and exercise to maintain appropriate muscle tone. A proper diet is recommended not only for its health benefits, but also as a preventive measure to avoid issues with obesity in adulthood.

Infants with SEDC may experience delayed development, such as difficulty sitting up or walking. Additional complications associated with this condition include chronic ear infections, sleep apnea, and fluid collection around the brain, a condition known as hydrocephalus. Adults with SEDC are more prone to develop arthritis, obesity, and a progressive curvature of the spine as they age. Women with SEDC who become pregnant are at an increased risk for developing respiratory issues during pregnancy and may require a cesarean delivery.