Efficacy of orthotic immobilization of the unstable subaxial cervical spine of the elderly patient: investigation in a cadaver model.

OBJECTIVE To assess the efficacy of soft, semirigid and hard cervical collars to immobilize the neck in a destabilized cadaver model. DESIGN This is a laboratory experiment. SETTING The anatomy research lab of McMaster University. PATIENTS None. Fresh cadavers from elderly patients suffering terminal medical illness and free of cervical structural disease were studied. INTERVENTIONS Destabilizing discoligamentous lesions of the neck were created in the cadavers. Radiographs were taken in maximum displacement in the prone, decubitus and side-bending positions, first unsupported and then with soft, semirigid and hard collars applied. Displacements in angulation and translation were measured from the radiographs. OUTCOME MEASURES Radiographic displacement under gravity load. RESULTS In all cases there was no effective limitation of pathological displacement, and in many cases displacement was increased after collar application. CONCLUSIONS Cervical collars do not effectively support the unstable neck, and may be ineffective in preventing pathological displacements.