RISK-FACTORS OF MYELOPATHY AT THE ATLANTOAXIAL LEVEL IN SPONDYLOEPIPHYSEAL DYSPLASIA CONGENITA

Spondyloepiphyseal dysplasia congenita (SEDC) can be accompanied by hy poplasia of the odontoid and/or lax ligaments which may lead to spinal cord compression. Since an early diagnosis of myelopathy is essential for rational treatment, identification of the high-risk factors is im perative. Sixteen patients were retrospectively reviewed, 10 male and 6 female, and their average age at the time of examination was 18 (ran ge 3-37) years. Myelopathy was seen in 6 individuals. Five were associ ated with atlantoaxial subluxation, and the critical value of space av ailable for the spinal cord at the level of the atlas was 10 mm or les s. Their height was less than -7SD of average Japanese of the same age , and all were associated with severe coxa vara. Although SEDC itself is a risk factor, marked short stature of less than -7SD and severe co xa vara are particularly high-risk factors for cord compression at the level of the atlas.