Abstract
1. In thirty-six out of seventy-two cases of cervical vertebral interlocking, luxation was still present after two weeks ("old luxation"). The principal reasons for overlooking the diagnosis are lack of familiarity with the radiographic appearances and incomplete or inadequate radiographic examination.
2. Failure to identify luxation probably hardly influences the prognosis of the immediate cord lesion; but recovery from the radicular lesion is unfavourably affected, and a progressive cord lesion may occur later when none previously existed.
3. Reduction is advisable if the luxation is not more than six weeks old. Operative reduction is preferred; manual reduction under anaesthesia and caliper traction with heavy weights are less satisfactory alternatives. Reduction is contra-indicated if the luxation is more than six weeks old.
4. Indications for fixation and the choice between internal and external (plaster jacket) fixation are discussed, and also the treatment of stable lesions which have not been reduced.