The orthotic management of spinal trauma remains an essential treatment option. However, the indications for orthotic management are constantly changing because of the evolving concepts of stability, indications for surgery, and surgical techniques. The complications traditionally associated with the surgical management of certain spinal fractures have significantly decreased with the increasing prevalence of minimally invasive techniques. This influences the indications for orthotic use in some trauma scenarios. However, the principles and expectations of orthotic use remain constant and an important option in the treatment of spinal trauma. One must determine the stability of the injury and the stabilizing ability of the orthoses available when considering the appropriate orthotic. This decision-making process is, therefore, specific to the individual fractures and their respective level of injury.
Spinal orthoses can be used by a member of the emergency medical service to provide initial immobilization, as temporary management until the surgery is performed, as the definitive management, or as an adjunct to surgery. The principle of preventing motion in the adjacent joints, as used in the extremity, also applies to the spine. However, when using spinal orthoses, the goal is not only to immobilize the motion segments adjacent to the injured level but also the functional levels adjacent to the injured spinal region (i.e., occipitocervical or thoracolumbar). As such, when stabilizing the cervical spine, the head and the thoracic spine must be included so that the occipitocervical and cervicothoracic levels are immobilized or, when stabilizing the lumbar spine, the pelvis and the thoracic spine are immobilized. Compared with surgical management of spinal disorders, the use of orthoses may seem benign; however, it is not without risks and complications. These devices may be associated with skin irritation, muscular atrophy, osteopenia, joint stiffness, severe discomfort, and even death.
The purpose of this chapter is to review the different types and function of spinal orthoses, commonly encountered adverse effects, and the principles in their use for the nonoperative treatment of selected spinal trauma.
Cervical Orthosis
The orthotic devices commonly used to immobilize the cervical spine after trauma are grouped into cervical collar, poster brace, cervicothoracic orthosis (CTO), and halo-vest device ( Table 39-1 ). The unique anatomy within the upper cervical spine and subaxial spine makes immobilization challenging, and the choice of device remains dependent on the location of the injury. The stabilization of the cervical spine depends on the ability to immobilize the skull proximally (usually via occiput and the mandible) and the clavicle or thorax (or both) distally. Hard contact against the mandible and occiput are associated with skin irritation and impairment of mandibular movement can interfere with mastication. Increased rigidity of the device can increase these adverse effects. Distal immobilization is challenging because the clavicle moves with shoulder motion and the soft tissues around the shoulder and the upper trunk are variable in size and shape. All of these factors, along with the degree of injury, must be taken into consideration. The clinician must choose a device that meets the patient’s specific needs while minimizing adverse effects.
Cervical Orthosis | Characteristics | Common Types |
---|---|---|
Soft collar | Proprioceptive feedback to the patient Reduced cervical motion by 5% to 20% | Serpentine, Form fit, Universal, Ruffs |
Hard collar | Plastic bivalved shell, lined with removable pads, connected by Velcro straps More sagittal motion control than axial or lateral motion | Philadelphia, Aspen, PMT, Cervmax, Miami J |
Cervicothoracic | Superior restriction of lateral and axial motion than collars Head controlled by padded mandibular and occiput supports; rigid uprights attach head to thoracic plates and straps | SOMI, Minerva, Guilford, poster brace |
Halo vest | Most effective method of upper cervical and occipitocervical stabilization Halo ring around head secured to thoracic vest Subaxial snaking phenomena possible |
Cervical Collar
The cervical collar is generally categorized into soft and hard options; both extend between the occiput and the mandible down to the clavicle. The soft collar ( Fig. 39-1 ) provides very little support or stability to the cervical spine. It has been shown to only reduce cervical motion by approximately 5% to 20%. The primary purpose of the device is to provide some proprioceptive feedback to the patient. Although the least stabilizing of all the cervical collars, it is also the least expensive and is associated with minimal patient discomfort. Generally, patients with whiplash injuries and posttraumatic neck pain may be treated with a soft collar for a short time so as to limit the associated potential for deconditioning, increased stiffness, and psychological dependence. In postoperative patients, we may use cervical ruffs, made from stockinette filled with cotton padding, loosely tied around the patient’s neck to provide proprioceptive feedback, reassurance, and a visual reminder to caregivers of the patient’s postoperative state.
The hard cervical collars are the most commonly used cervical orthoses. There are many commercially available variants of the collar, the most common being the Philadelphia, Aspen, PMT, Cervmax, and Miami J ( Fig. 39-2 ). Most of the collars consist of a plastic bivalved shell that is lined with removable pads (however, the Philadelphia collar consists of two plastic-reinforced Plastazote shells). The anterior shell encompasses the mandible and chin superiorly and rests on the anterior chest, sternum, and clavicles. The posterior shell lines the occiput around to below the ears and rests on the upper back and trapezium. The anterior and posterior shells are connected by Velcro straps. The hard cervical collars tend to be more effective in minimizing motion in the sagittal plane compared with lateral bend and axial rotation. Multiple biomechanical studies have compared the effectiveness of these devices. Most commercially available cervical collars appear to be effective in immobilizing the spine, but some models may be more comfortable for the patient than others. Importantly, the improper fitting of the hard collar, whether it is too small or too big, will have a significant effect on the ability of the collar to limit cervical motion in all planes (flexion-extension, axial rotation, and lateral bend). These devices are commonly used to immobilize the cervical spine as part of cervical spine precautions in trauma patients until the cervical spine is safely cleared. Some of the rigid collars initially applied by the emergency medical service are often less padded than those described earlier. In all cases, it is important that these devices be removed as soon as injury to the cervical spine is excluded to limit the potential complications of skin irritation, difficulty with ingestion and speaking, and general discomfort. Furthermore, the use of rigid collars has the potential to increase intracranial pressure, which can be perilous in patients with traumatic brain injury.
Cervicothoracic Orthosis and Poster Braces
Compared with the hard cervical collars, CTOs and poster braces provide better restriction of motion in axial rotation and lateral bend. CTOs are designed to be more effective in immobilization of the cervical spine than cervical collars because of the more extensive chest plates. The poster brace and the CTO are similar devices with the CTO extending slightly more distal and incorporating more of the chest, usually with a circumferential strap. The poster brace is best described as a cervical collar with extension down to the chest and/or back. CTOs and poster braces control the head through padded mandibular platforms and supports at the back of the occiput. Rigid uprights then attach the head to the thorax via thoracic plates or straps. Examples of these orthoses include the Minerva brace ( Fig. 39-3 ), the SOMI (sternal-occipital-mandibular immobilizer) brace ( Fig. 39-4 ), and commercially available hard collars outfitted with extension pieces to both the skull and chest. The poster braces connect the mandibular and occipital pads to the torso by two or four metal struts.
The SOMI brace consists of a rigid anterior chest plate that extends over the shoulders and connects to the occipital pad. The chin piece is removable for eating and can be reinforced with a strap that spans across the forehead. Unlike the Minerva brace, the SOMI brace does not have a posterior chest plate so it is more comfortable for patients confined to bed. The SOMI brace has been extensively studied compared with a variety of hard collars. There appears to be very little difference between the braces’ ability to stabilize the cervical spine, except for flexion-extension, for which a difference has been shown favoring the SOMI brace. Johnson and colleagues demonstrated that the SOMI brace is significantly better at controlling flexion between C1 and C5 than the cervical hard collar (Philadelphia collar), CTO, and four-poster brace but was very poor at controlling extension in the same location.
The addition of posters to the hard collar improves the control of flexion-extension, lateral bend, and rotation. Apart from the halo-vest orthosis, the CTO, such as the Minerva and Guilford, is the best immobilizer for all planes of cervical motion. It is important to note that all cervical orthoses are not particularly effective at limiting flexion-extension at the occipitocervical spine compared with segmental motion in the upper cervical and subaxial spine. Improved immobilization comes at the expense of patient comfort and the risk of skin breakdown. Use of these more rigid orthoses in cognitively impaired patients risks occipital and mandibular skin ulceration.
Halo-Vest Device
The halo fixator is a device that connects the head to the thorax. In adults, four pins are placed that pierce the outer table of the calvarium and secure the halo ring around the head. The halo-vest device is generally accepted as the most effective method of upper cervical spine stabilization including the occipitocervical junction and is superior to all other orthotic devices discussed earlier. However, some vertebral segmental motion, on average 7 degrees of angulation and 1.7 mm of translation, can be detected at the injured level in the majority of patients. Furthermore, the halo-vest device can be associated with a snaking phenomenon, whereby neck muscle contraction causes translation of individual vertebrae in the midcervical spine producing focal kyphosis caused by immobilization of the upper and lower segments. The halo-vest device is commonly used to stabilize the cervical spine when the rigid collar and CTOs are deemed to be insufficient. When using this device, careful consideration must be given to patient selection to avoid complications. Absolute contraindications to the use of the halo ring include cranial fractures and infection or severe soft tissue injury at proposed pin sites. Relative contraindications include chest trauma, obesity, pregnancy, advanced age, and barrel-shaped chest. The elderly population is particularly at high risk of halo vest–related complications with a mortality rate reported to be as high as 40%. In this patient cohort, the mortality and major complication rates of those treated with halo-vest devices are significantly higher than compared with those treated with cervical collar.
Recommended Orthoses for the Nonoperative Treatment of Selected Cervical Injuries
For all fractures, the potential for surgical intervention must be excluded before initiating conservative care. Indications for surgical intervention are discussed in detail within other chapters of this textbook.
C1 Ring Fracture
For minimally displaced fractures of the C1 ring, we commonly use a hard cervical collar because this injury pattern is relatively stable. For potentially unstable Jefferson fractures (i.e., C1 ring burst fractures), a halo-vest fixator or CTO if the halo vest is contraindicated can be used with the goal of preventing either C1-C2 instability caused by transverse ligament injuries or deformity secondary to C0-C1 or C1-C2 lateral mass malalignment.
Transverse Ligament Injuries
When an avulsion fracture has disrupted the integrity of the transverse ligament, management in a cervical orthotic may be considered. In this case, flexion at the C1-C2 level should be immobilized using either a CTO (a SOMI brace best controls upper cervical spine flexion) or halo-vest device.
Type II Odontoid Fractures
If orthotic management of this fracture is selected, then the age of the patient will determine the type of orthotic selected. For patients younger than 65 years of age, the halo-vest device should be chosen to provide the best immobilization of this fracture. If the fracture pattern is noncomminuted and nondisplaced and in a reverse oblique fracture pattern (which predisposes the peg to anterior translation relative to the C2 body), then a SOMI brace may be considered. In the elderly population, we use the hard cervical collar if the fracture is to be treated nonoperatively. The expectation of this approach is to achieve a relatively stable fibrous nonunion, but not necessarily consolidation, of the fracture.
Type III Odontoid Fractures
A hard collar for the elderly population is recommended for this fracture. We recommend either a hard collar or CTO for the nonelderly adult population.
C2 Pars Fractures (Hangman’s Fractures)
In the case of a stable hangman’s fracture with no or minimal displacement, we recommend the use of a hard collar or CTO.
Spinous Process Fractures, Laminar Fractures, and Compression Fractures of the Subaxial Spine
These fractures are stable injuries that are well treated in a hard collar.
Facet Fractures of the Subaxial Spine
The CTO is most appropriate for this potentially unstable fracture.