1. A technique of functional roentgenography of the cervical spine is described as an aid in establishing an anatomical diagnosis of subluxations and obscure dislocations.
2. Four cases are presented with roentgenographic and operative findings: (a) marked unilateral apophyseal joint subluxation; (b) unilateral fracture-dislocation; (c) unilateral fracture of the articular process; and (d) minimal unilateral apophysealjoint subluxation.
3. It is suggested that the ligamentum flavum is important in the stability of the cervical spine.
4. Obscure anatomical lesions of the cervical spine are best demonstrated at operation with the patient awake and sitting on the regular operating table, the laminectomy head rest being used.