Spinal bone mineral density changes following halo vest immobilization for cervical trauma.

In this prospective study we followed the bone mineral density (BMD) changes of the injured cervical spine immobilized with the halo vest. In order to define the natural history of cancellous vertebral bone loss and restoration, dual-energy densitometry was used on each of ten selected cervical spines in the lateral view (1) immediately after the application of the device, (2) at the end of the treatment and (3) 3 months after the removal of the halo vest. The halo vest produces local osteoporosis in the immobilized cervical spine with an overall reduction of BMD averaging 2.83% (P < 0.05). The response of the cervical spine to immobilization was only slightly different from patient to patient and between different vertebral bodies in each particular spine. The type and the level of injury of the cervical spine were not related to the changes of BMD, age or gender of the patient, whereas the local osteoporosis was mostly reversible in the follow-up evaluation of 5-6 months.