| [ Summary ] |
Skeletal dysplasias are a heterogeneous group of more than 200 disorders characterized by impaired cartilage and bone growth, resulting in abnormal skeletal shape and size and disproportionate long bones, spine, and head. Approximately 1/4,000 newborns are diagnosed with skeletal dysplasias. Based on the underlying molecular genetic cause, dysplasias can be broadly grouped by the function of the protein product of the causative gene. This type of classification is clinically useful because many of the disorders caused by genes whose protein products have similar functions also share clinical characteristics. Disproportionately short stature (short limbs or short trunk), delayed motor milestone, and airway obstruction may be noted. Pain, deformity, and minor or major neural deficits, such as paraparesis and quadriparesis, can be caused by spinal disorders. A large head with hydrocephalus and bowlegs with waddling gaits are also observed. Treatment is supportive. Medical care for individuals with skeletal dysplasia should be directed at preventing neurologic and orthopedic complications due to spinal cord compression, joint instability, and long bone deformity. |