Cervical kyphosis in diastrophic dysplasia.

STUDY DESIGN: An evaluation of cervical kyphosis in diastrophic dysplasia from newborn to adult life.

OBJECTIVES: To discover the prevalence and natural history of cervical kyphosis in diastrophic dysplasia.

SUMMARY OF BACKGROUND DATA: Typical findings in this rare skeletal dysplasia are sport-limbed short stature, multiple joint contractures, early degeneration of joints, and spinal deformities such as cervical kyphosis, scoliosis, and exaggerated lumbar lordosis. In diastrophic dysplasia, spontaneous resolution of cervical kyphosis has been reported, but so have severe forms causing medullar compression leading to quadriplegia and death. The prevalence and clinical outcome of the kyphosis are not known.

METHODS: The radiographic natural history of the cervical spine was studied in 120 patients. They varied in age from newborns to 63-year-olds. The average follow-up time in 26 living patients with cervical kyphosis was 10.0 years.

RESULTS: Midcervical kyphosis was noted in 29 patients (24%) in their first radiograph. In 25 patients, the first radiographs were taken before the age of 18 months, and 24 of these patients (96%) had cervical kyphosis. The most severe case was that of a 32-year-old patient with a 165 degrees kyphosis. In the 24 patients, the kyphosis resolved spontaneously at an average age of 7.1 years. Three patients with a severe kyphosis died; one patient is alive. One patient, a 4-year-old child has mild resolving deformity.

CONCLUSIONS: Cervical kyphosis in diastrophic dysplasia usually is shown at the time of birth. It resolves spontaneously during growth and seldom needs treatment. Careful follow-up study and treatment, if necessary, are important tools for avoiding the neurologic problems and fatal outcome.