Distinct genetic syndromes (achondroplasia, Down's syndrome) are associated with congenital or degenerative vertebral abnormalities and with involvement of the ligamentous apparatus. In patients with achondroplasia, vertebral deformities may result in spinal stenosis, nerve root compression and development of myelopathy.
The most common spinal complication in Down's syndrome is atlanto-axial instability. This condition is associated with a shift of C1/C2 vertebrae and subsequent compression of dorsal roots, spinal cord and the development of cervical myelopathy.
Two case reports of patients with these genetic disorders are presented. Surgical intervention was considered necessary in both of them.