Atlanto-axial subluxation
- In rheumatoid arthritis, atlanto‐axial subluxation can occur due to destruction of the synovial joint between the atlas and the dens and rupture of the transverse ligament
- Subluxation can result in cord compression which can be fatal
Management
- Less severe cases (seen on flexion‐extension views) may be treated with a collar to prevent flexion
- More severe cases may require surgical fusion
Lower cervical subluxations
- Lower cervical subluxations can occur due to destruction of the synovial facet joints and uncovertebral joints by RA
- There is potential for cord compression (myelopathy) with upper motor neuron signs (wide based gait, weakness, increased tone, upgoing plantar response)
- Measurements are taken from flexion‐extension x-rays
Management
- If instability does not involve/threaten neurological structures - conservative management (analgesia, physio)
- More severe cases may require stabilisation/fusion
Other causes of atraumatic cervical spine instability
- Atraumatic cervical spine instability can also occur in Down's syndrome