Twenty-three cases of acute spinal cord injury in persons with cervical ankylosis are presented. Certain characteristics of major sub-groups are described: ankylosing spondylitis (N = 8), degenerative spondylosis (N = 9) and congenital fusion (congenital non-segmentation) (N = 6). The ankylosing spondylitic group presented a grim prognosis for survival (death rate 50 per cent within 60 days) and for loss of neurological function. Five out of eight cases had permanent neurological loss subsequent to their injuries. Both the ankylosing spondylitic and degenerative spondylotic groups presented problems in diagnosis and medical management. The basic principle is immobilisation of the fracture and mobilisation of the patient. The halo is the technique of choice for fracture immobilisation. An integrated intensive respiratory management programme is essential. Patients with ankylosed spines, particularly those with ankylosing spondylitis, should be educated in simple measures to prevent fracture of their spines.