Last Updated on November 22, 2023
The halo vest consists of a halo ring and vest. The halo ring is the part that encircles the head and is fixed to it by means of pins that are inserted in the head. It is also known as “halo ring” or “halo crown,”.
It is a device that immobilizes the neck by restraining the cranium to the torso. It can be used both in adults and children.
It provides greater immobilization as compared to other conventional methods of immobilization.
Halo vest immobiliser is used in the management of cervical spine diseases where the spine needs external stabilization. The halo ring part of the halo vest can be used to put traction on the cervical spine or to provide external support and immobilization.
Halo vest immobilizer can be used for temporary fixation and definitive treatment. [See indications below]
Image Credit: http://radiographics.rsna.org/content/24/1/257/F36.large.jpg
The concept of was first brought out in the late 1950s. Before this only method to effectively restrict cervical spine mobility was traction in the recumbent position. In contrast, a halo vest allows sitting and moving around.
Thus complications of recumbency like bed sores and chest infections can be avoided.
A halo ring can be used to put traction and close reduction of fractures.
Relevant Anatomy
The anterior safe zone for pin placement is located 1cm superior and over the lateral two-thirds of the rim of the orbit.
The most medial extent of the safe zone is approximately 4.5 cm from the midline in the sagittal plane, medial to which lies terminal branches of the ophthalmic division of the trigeminal nerve. These are supraorbital [lateral]and supratrochlear nerves [medial].
The frontal sinus also lies to the medial to the safe zone and needs to be avoided by sticking to safe zone. Otherwise, the thin bone above the sinus is prone to perforation.
Lateral to the soft zone, the temporal bone is thinner. The Temporalis muscle and the zygomaticotemporal nerve also lie laterally. Any pin put too lateral or medial risks these structures.
Indications of Halo Vest Application?
Halo vest can be used in following situations in cervical spine injuries or other pathologies that affect the stability of the spine
- To stabilize the spine for treatment with nonoperative means
- Reduction of cervical spine fractures
- In adjunct with a surgical procedure to provide additional stability
- In follow-up to patients who were treated initially with skeletal traction.
So, the halo vest can be used in the following indications
Definitive Use
Here, the halo is used as a definitive treatment
[Read more on Upper Cervical Spine Injuries]
Adults
- Occipital condyle fracture
- Occipitocervical dislocation
- Stable type II atlas fracture
- Type II odontoid fractures
- Type II and IIA hangman fractures
Children
- Upper cervical Injuries
- Atlantooccipital dissociation
- Jefferson fracture
- Atlas fractures
- Unstable odontoid fractures
- Persistent atlantoaxial rotatory subluxation
- C1-C2 dissociations
- Subaxial cervical spine trauma
- Congenital scoliosis
- Reduction of injury before surgery
Temporary use
- Postoperative immobilization after cervical spine surgery
Contraindications to Use of Halo Vest Immobilizer
- Infection
- Skull Fractures
- Patients who might need craniotomy
- Poor soft tissue over the pin insertion site
- Relative COntraindications where individual decisions can be made
- Multiple system injuries
- Chest and lung injury
- Obesity
- Barrel-shaped chest [May lead to fitting issues]
- Advanced Age (greater complications)
Advantages of Halo over Traditional Immobilization of Cervical Spine
A ring is fixed to the patient’s head by means of screws and the ring is attached to a rigid, lightweight vest that fits snugly around the patient’s chest.
This way the apparatus can provide spinal stability while allowing mobility.
Halo vest offers the following advantages over the traditional traction system
- Precise positional control
- Efficient external stabilization of the cervical spine
- Low complication rate
- Minimal patient discomfort,
- Early patient mobilization.
Thus Halo vest applications offer the most stable form of external immobilization of the upper cervical spine. In contrast to bracing, a halo vest assembly allows for some fracture manipulation and correction of malreduction.
If a halo vest assembly is correctly placed, neck motion can be expected to be limited to 4% of normal flexion-extension, 4% of lateral bending, and 1% of rotation.
Application of Halo Vest
Measure the circumference of the head and select the appropriate size of the halo ring. There should be 1-2 cm skull clearance.
The halo ring can be placed under local anaesthesia in conscious patients.
Before the ring is placed, a halo vest of the appropriate size should be available so that the ring can be connected to the vest after application.
Place the ring in the desired position and fix it temporarily with pins
Screws
- Anterior screws – 1 cm above the lateral 1/3 of the eyebrows
- Posterior screws- Approximately 5 cm posterior to the ear
Adults require 4 screws, children 6-8
Keep the lids closed during screw insertion
Confirm the screw position on the x-ray.
Bring the cervical spine to the desired position and connect it with a halo vest or jacket.
A neurological examination is made after the application of the halo vest.
The duration of application varies depending on the nature of the injury and the purpose for which the halo vest is applied.
The assembly is well tolerated by most of the patients.
Patients are regularly followed up with a series of radiographs and neural examinations.
In the follow-up, screws are tightened on next day and then rechecked after further two days. Weekly check of screw tightness should be done.
Complications of Halo Vest
- Pin loosening
- Most common
- This can be avoided by early detection of loosening at weekly follow-up visits.
- Infection at the pin sites
- 10-20% of patients
- Local cleaning and oral antibiotics in most cases
- Pin removal and another pin placement may be required in certain cases.
- Secondary loss of reduction
- Due to the “snaking” mechanism of the cervical spine between the supine and upright positions
- Does not affect stable fractures
- But could cause problems if the fractures are inherently unstable where Halo may not provide the best of immobilization.
- Nerve Injuries
- Greater occipital nerve palsy
- Supraorbital nerve palsy
- Supratrochlear nerve palsy
- Abducens nerve palsy
- Injury to the 6th cranial nerve
Complications are more common in children.
Selfcare in Halo Vest Immobilzer – Dos and Donts
- Hygiene: Take sponge baths. Use hair dryer or blower if the vest gets wet. Wrapping the vest area and neck in a plastic bag helps to keep the water off the vest. Cornstarch on the junctional areas after the bath may help you to absorb any inadvertent moisture.
- Eating: As you cannot bend the neck, use straws and modified or customized cutlery to aid in eating.
- Ambulation: The greatest advantage of a halo brace is that it allows being upright and mobile. But walking with a brace on that does not allow bending or turning of the neck and may be difficult. Move slowly and with deliberation till you get used to the brace. Do not drive.
- Sleeping: Sleeping can be another issue. A reclining chair can help. Placing a towel or pillow under the neck helps as well.
- Seek Help When Needed:
- When there is a pain that worsens
- The brace has displaced
- There is a fall
- Pin site swelling or discharge
- Unrelenting headache
- There is a problem with swallowing, speaking, moving, blurred thinking or vision
Halo Brace Removal
Halo vest removal is an outpatient procedure. There is no need for sedation and patients are awake.
First, the vest is removed and the uprights connecting to the halo ring are removed. Then the nuts are removed which loosens the ring. Then the pins are unscrewed while the ring is held.
References
- Bransford RJ, Stevens DW, Uyeji S, Bellabarba C, Chapman JR. Halo vest treatment of cervical spine injuries: a success and survivorship analysis. Spine (Phila Pa 1976). 2009 Jul 01;34(15):1561-6. [Link]
- Bono CM. The halo fixator. J Am Acad Orthop Surg. 2007 Dec;15(12):728-37. [Link]
- Kang M, Vives MJ, Vaccaro AR. The halo vest: principles of application and management of complications. J Spinal Cord Med. 2003 Fall;26(3):186-92. [Link]