Spinal Traction

Summary of Key Points

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Spinal traction is an effective nonoperative treatment strategy for cervical fractures, dislocations, destabilizing conditions, and deformity.
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Methods of spinal traction include head halter traction, Gardner-Wells tongs, and cranial halos.
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The most common indication for weighted traction is the treatment of cervical facet dislocation.
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When applying traction to a patient with a cervical injury, the patient must be followed with serial clinical examinations and radiographs to monitor for change in neurologic condition and spinal alignment.

Spinal traction is a nonoperative treatment strategy for spinal trauma and deformity that utilizes longitudinal force to restore spinal alignment, achieve indirect spinal cord decompression, and provide stabilization. Traction may be used as a standalone therapy or may be used as a bridge until definitive surgical stabilization is possible. Traction has been used as a treatment for spinal trauma and deformity since the 4th century bc , when the Greek physician Hippocrates invented devices to reduce fractures and restore spinal alignment in patients with scoliosis. In the 17th century, the German surgeon Fabricius Hildanus described a novel method for reducing cervical fracture-dislocations that involved placing a needle under a cervical spinous process, which was attached to forceps and placed under traction. Modern traction strategies can be traced to 1929, when A.S. Taylor used a halter device to apply traction in reducing a cervical dislocation before immobilizing the patient in a plaster jacket for 3 to 4 weeks. In the mid 20th century, traction was seen as a safer alternative than manual reduction of cervical fractures, which was still in use at the time. During this period, Crutchfield further developed traction techniques for cervical injuries and developed tongs that were inserted into the skull for this application. The halo device, which consists of a halo ring placed around the head fixed to a rigid body cast, was first described in 1959 as a treatment for arthrodesis of the cervical spine in polio patients and later adapted for use in cervical spine injuries. Today, traction remains an effective and widely used method to reduce fracture dislocations in the cervical spine. In contrast, the role of traction in the conservative management of lumbar spine pathology is unclear, and its use has not been supported by data from prospective clinical studies.

Indications for Use

Indications for the use of traction in the cervical spine include facet dislocation, lateral mass fractures, displaced odontoid fractures, rotatory atlantoaxial subluxation, kyphotic deformity, and other destabilizing infectious, neoplastic, and autoimmune cervical spine conditions. Relative contraindications to cervical traction are extension distraction injuries, atlantooccipital subluxation or dislocation, young age (< 3 years), and types IIa and IIIa hangman’s fractures. Extension injuries are particularly unstable, and weighted traction may result in an undesirable degree of interspace distraction. Traction may produce change in neurologic examination in a patient with an unstable spinal injury. Hence, traction may have risk in patients with depressed levels of consciousness who cannot be monitored clinically. Similarly, care should be taken to not over sedate patients undergoing traction.

Head Halter Traction

The head halter device provides a noninvasive means of applying traction to the cervical spine. Indications for head halter traction include atlantoaxial rotatory subluxation (AARS), stable cervical fractures, and conservative management of neck pain and cervical radiculopathy. The head halter devices consists of two pads, placed under the chin and occiput attached to a rope connected to a pulley and weights. The device may be used in the inpatient setting or at home, though the patient must have the pads properly fitted to ensure even distribution of force to both pads.

In a study of 40 children with AARS, treatment with a cervical collar was effective in reducing subluxation in 21 patients, and of the 7 patients requiring halter traction, 4 patients demonstrated progression of subluxation and required halo traction. In a study of 14 children with acute AARS, all patients experienced spontaneous reduction with a cervical collar and bed rest without the need for halter traction, suggesting that most patients with acute AARS do not require halter traction to achieve reduction.

In a retrospective review of 81 patients with cervical radiculopathy treated with 8 to 12 pounds of halter traction applied for 15 minutes three times per day for 3 to 6 weeks, 78% of patients experienced significant or complete resolution of painful symptoms. Halter traction may also be used to reduce stable cervical fractures. In a study of 20 patients with traumatic spondylolisthesis, fracture union was achieved at a mean of 13 weeks.

Gardner-Wells Tongs

Gardner-Wells tongs were first described in 1973 and continue to be in use today due to their safety, efficacy, and ease of use. The device consists of a spring-loaded C-shaped rod that attaches to the skull using two-point fixation. A rope is attached to the center of the rod by an S-shaped link in order to apply gradual weighted traction across a pulley placed at the head of the patient’s bed.

To place Gardner-Wells tongs, the pins are positioned through the outer table of the skull approximately 2 to 3 cm superior to the pinna and below the equator of the calvarium ( Fig. 135-1 ). Most commonly, the patient is placed supine with the head flat on a hard surface. Placement of pins in line with the external auditory meatus (EAM) generates direct axial traction, with pin positioning anterior to the EAM favoring neck extension and pin placement posterior to the EAM favoring neck flexion. The location of pin placement differs according to the clinical scenario.

Traction is applied in the axis of flexion for unilateral or bilateral facet dislocations to achieve proper realignment. For displaced odontoid fractures, bi-vector traction using both longitudinal and flexion forces are often required to achieve reduction. Additionally, the degree of flexion or extension can be further modified by modulating the height of the pulley in order to modify the angle of the traction line. Raising the pulley typically favors neck flexion, whereas lowering the pulley favors neck extension. Care must be taken in applying cervical traction in patients with a fixed spinal deformity and instability (for example, a patient with ankylosing spondylitis, kyphotic deformity, and cervical fracture). In the patient with a fixed spinal deformity and instability, the physician must remember the goal is to restore spinal alignment, achieve indirect spinal cord decompression, and provide stabilization; this may require applying the traction force with significant flexion/extension. After the pin sites have been selected, the pin sites are prepared with antiseptic solution and infiltrated with a local anesthetic agent. Shaving of the pin sites is not necessary. The two pins are secured into place simultaneously until the indicator stem protrudes 1 mm to demonstrate that 25 pounds of force have been applied. The tongs are gently rocked back and forth to set the pins in the outer table, and nuts are used to secure the pins in place. Weighted traction is applied, and 12 to 24 hours later the pins must be gently retightened. Further tightening of the pins after this point may cause the pins to violate the inner table and is not recommended. After reduction has been confirmed by radiograph, the weighted traction can be decreased by 5 to 15 pounds or to approximately 20 pounds ( Fig. 135-2 ).

Complications from Gardner-Wells tongs include pin-site infections, pin dislodgement, and, in rare cases, pin penetration of the inner table of the calvarium. Pin placement may be contraindicated in many patients with a skull fracture, cranial defect, bone disorder, or previous cranial surgery. Device failure due to pin detachment may lead to serious neurologic injury. Biomechanical cadaveric studies suggest that the pull-off strength of Gardner-Wells tongs is approximately 140 pounds when the indicator stem protrudes 1 mm. The pin sites should be treated daily with an antiseptic agent.

Patients maintained in cervical traction have risks of developing pressure ulcers and may have impaired pulmonary toilet. Associated injuries in the polytrauma patient may increase the risk of these and other procedural complications. Hospital beds that allow for turning of the patient and for monitoring of skin integrity should be considered in patients treated even with short periods of cervical traction.

Cranial Halo

The halo device includes a ring that utilizes four-point skeletal fixation used to apply weighted traction in a manner similar to Gardner-Wells tongs. The four-pin design of the cranial halo allows it to support greater traction loads, and greater force is required to detach pins than with two-pin systems. Different manufacturers may have different specifications of the maximum amount of weight that may be applied with a halo ring fixator. The cranial halo can be attached to a rigid vest once spinal reduction has been confirmed in order to provide cervical spine stabilization while the patient is mobile.

Prior to applying the halo ring, the patient’s head circumference is measured and a halo ring that provides 1 to 1.5 cm of clearance from the scalp is selected. A local anesthetic solution is injected in the location of the four pin sites before the pins are applied to the outer table of the skull. The anterior two pins should be placed 1 cm superior to the eyebrow with care taken to avoid injuring the supraorbital nerve ( Fig. 135-3A ). The posterior pins are placed 1 to 1.5 cm superior to the ears bilaterally. While an assistant holds the head in place, hexagonal lock nuts are placed outside the ring before the four pins are threaded through the ring in a manner perpendicular to the skull until the pins penetrate the outer layer of the dermis ( Fig. 135-3B ). Care is taken to not shift the pin locations during tightening by tightening two diagonally opposed pins at a time until the pins have engaged the outer table. Diagonal sets of pins are then tightened alternately with a torque wrench to 8 inch pounds. Pin torque above 10 inch pounds is associated with increased risk of penetrating the inner table and should be avoided. After this has been achieved with each pin, the nuts are threaded into place against the halo ring to prevent the pins from backing off the outer table. After 24 hours, the hexagonal nuts are loosened and the skull pins are retorqued to 8 inch pounds. As pin site infection is one of the most common complications of the halo device, pin sites should be treated daily with an antiseptic solution such as bacitracin or dilute hydrogen peroxide. Other complications of cranial halo include pin loosening, cranial nerve injury, bradycardia in children, and penetration of pins through the inner table, which can lead to pneumocranium.