The halo is a device for treatment of unstable cervical and upper thoracic fractures and dislocations from C1 to T3. The halo provides greater motion restriction than any other cervical orthosis. The halo ring is made of graphite or metal, with pin fixation on the frontal and parietal-occipital areas of the skull. Development of lightweight composite material led to the design of radiolucent rings that are compatible with magnetic resonance imaging (MRI). The halo ring attaches to the vest anteriorly and posteriorly via 4 upright bars.
The halo vest has shoulder and underarm straps for tightening; it is usually made of rigid polyethylene and extends down to the umbilicus. Restriction in cervical motion depends on the fit of the halo vest. An improper fit can allow 31% of normal spine motion; compressive and distractive force can occur with variable fit of the vest.
• Flexion and extension are limited by 90-96%
• Lateral bending is limited by 92-96%.
• Rotation is limited by 98-99%
• Dens type I, II, or III fractures of C2 (Note: Dens type III fractures of C2 are treated more successfully with surgery.)
• C1 fractures with rupture of the transverse ligament
• Atlantoaxial instability from rheumatoid arthritis, with ligamentous disruption and erosion of the dens
• C2 neural arch fractures and disc disruption between C2 and C3. (Note: Some patients may need surgery for stabilization.)
• Bony, single-column cervical fractures
• Cervical arthrodesis – Postoperative
• Cervical tumor resection in an unstable spine – Postoperative
• Debridement and drainage of infection in an unstable spine – Postoperative
• Spinal cord injury (SCI)
• The halo is the best orthosis for use in controlling rotation and lateral bending at C1-C3.
• Concomitant skull fracture with cervical injury
• Damaged or infected skin over pin insertion sites
• Cervical instability with 2- or 3-column injury
• Cervical instability with rotational injury involving facet joints
• Neck pain or stiffness – 80%
• Pin loosening – 60%
• Pin site infection – 22%
• Scarring – 30%
• Pain at pin sites – 18%
• Pressure sores – 11%
• Redislocation – 10%
• Restricted ventilation – 8%
• Dysphagia – 2%
• Nerve injury – 2%
• Dural puncture – 1%
• Neurological deterioration – 1%
• Avascular necrosis of the dens
• Ring migration
• Inadequate bony healing
• Inadequate ligamentous healing
When using the halo device, the following important considerations should be kept in mind:
• The halo fixation device is used for 3 months to allow adequate time for bone healing.
• The use of a CO after removal of the halo, when the neck muscles are weak and stiff, provides some support for the head.
• Approximately 40-45% of patients with facet joint dislocations achieve stability with the halo vest;
• 70% of patients without facet joint dislocations achieve stability.
• Nearly 75% of patients without facet joint dislocation achieve good anatomic results.
• In cases of facet joint dislocation, surgical stabilization improves the outcome.
• Patients with facet joint dislocation have a higher likelihood of SCI.
• Thorough neurologic examination before and after the reduction of facet joint dislocation is important.