We present a family with a radiologically distinct new form of autosomal dominant spondyloepiphyseal dysplasia, presenting with cervical instability and attendant neurological compromise and emphasise the radiological characteristics which delineate this condition. Cervical vertebral abnormalities, including malformation of the odontoid process, have been observed in some forms of spondyloepiphyseal dysplasia, but rarely lead to neurological sequelae, in contrast to the pedigree we describe.