C1 Fractures Treatment & Management

Patients with C1 fractures customarily have some form of trauma; thus, they need to be immediately stabilized at the scene, which requires the customary attention to the ABCs (airway, breathing, and circulation). If the airway is compromised or air exchange is inadequate, intubation without moving the head is crucial (C-spine protection). Careful evaluation and frequent reassessment is needed because the patient may have sustained a concussion with the impact to the head (the common injury that produces the C1 fracture) and, because of a clouded sensorium, may not be able to be fully evaluated or to report neck pain. Patients with a diminished alertness and orientation should carefully undergo imaging studies to exclude underlying pathology.

Vertebral artery dissection and neurological decline may occur with cervical trauma, emphasizing the above recommendation for arteriography. Basilar artery occlusion has been reported with chemical and mechanical thrombolysis, resulting in basilar artery patency and clinical improvement,^[9] whereas prior cases of basilar artery occlusion reported death and locked in syndrome.

Treatment of the C1 fracture consists of stabilization or immobilization in a satisfactorily reduced position to allow reliable healing. This illustrates the necessity of identifying associated injuries; for example, if a Jefferson fracture is identified but an associated odontoid fracture, transverse ligament fracture, or other problem is present, then halo treatment may be modified or less successful. The transverse ligament is not necessarily expected to heal tightly or reliably, although a bony fracture would be expected to have mechanical integrity restored when healed.

With a C1 fracture, the posterior aspect of the ring becomes disconnected from the anterior aspect, which is stabilized around the odontoid; thus, a posterior fusion of the occiput to C1 would be inadequate to stabilize the spine and, consequently, would extend at a minimum to C2. Customarily, instrumentation attaches a type of contoured rod or plate from the occiput down to C2 to stabilize the area and facilitate healing.

Direct lateral mass screws have been reported, allowing reduction and compression across the fracture, but more significantly preserving upper cervical motion segments.^[10] Occipital neuralgia has been reported with this technique,^[11] so this technique will find its place in the author’s armentarium with further reported experience.

A fractured odontoid fragment cannot be removed from the posterior approach; if a neurologic deficit or threat to the brain stem is present (the alar ligament may have an attached portion of the odontoid migrate superiorly into the foramen magnum to compress the brain stem at the pontomedullary junction), neurosurgical posterior decompression of the foramen magnum could be performed in a halo.

Alternative consideration may be given to a transoral approach or an anterior retropharyngeal approach for the combination of the Jefferson fracture and a fracture of the odontoid. The traditional treatment is a halo vest or cast until the Jefferson fracture is healed. Then, additionally, if the odontoid fracture healing has become delayed or a nonunion is present, this can be treated by a C1-2 arthrodesis, but the procedure must be delayed for the ring of C1 to heal.

For this combined fracture, an anterior open reduction and internal fixation of the odontoid may be performed, with 2 screws placed in an oblique fashion starting at the inferior anterior edge of C2 and directed cephalad to engage the odontoid. With a C1 fracture, this is done in conjunction with a halo vest. An alternative would be a Magerl approach of a posterior open reduction, accompanied by internal fixation of C1-2. For this procedure, 2 screws are placed in an oblique fashion starting at the inferior edge of the C2 lamina, and then they cross the C1-2 facet joint between the vertebral artery, which is lateral, and the spinal cord and brain stem, which are medial.

The patient must be maintained in protective immobilization—more than a soft collar for adults. Presumably, the patient is in a halo from the point of initial treatment. The reduction of an atlas fracture may be achieved by a ligamentotaxis with mild traction; however, traction is very risky, and such very unstable injuries have to be monitored extremely closely. Associated fractures must be identified expeditiously to direct subsequent treatment. Congenital abnormalities of the arch, such as an agenesis of the posterior ring, must be identified and taken into account in the treatment plan.

If the patient is awake and has a halo and vest applied, then the conversation and discussion with the patient during the procedure demonstrates the maintained safety and neurologic status of the patient. Patients who undergo surgical correction, particularly posterior arthrodesis, may be monitored with somatosensory evoked potentials.

After application of a halo, close follow-up is required with radiographs to demonstrate that the fracture is maintained in a satisfactory position for healing. If surgical stabilization is appropriate, then monitoring the healing of the bone fusion with radiographs is also crucial postoperatively.

Patients in the halo require at least 8 weeks, or likely 12 or more weeks, of immobilization until healing is documented on radiographs. This period is followed by one in which the patient is placed in a collar to protect the neck while he or she is being weaned from the halo and while the neck is gradually being rehabilitated in terms of intrinsic muscle stability and range of motion.

Patients with upper cervical instability are at risk of death; this risk is increased if the injury is not identified and recognized. Neurologic damage at this level could make the patient dependent on a ventilator; thus, extreme care is necessary in handling these patients during fracture healing.

Associated injuries to the occipitoatlantoaxial complex must be considered and included in the treatment plan. Devastating neurologic injuries may result from vascular embarrassment resulting from the instability of these injuries.

Patients with Jefferson fractures are expected to heal and have an excellent prognosis for resumption of activity in the absence of associated injuries. Any surgical stabilization severely restricts the motion of the head, because the occipitoatlantoaxial complex represents over 50% of the motion of the head on the trunk.

Disruption of the ring of C1 makes stabilization by a C1-2 fusion in the customary posterior fashion impossible; however, a C1-2 direct fixation with Magerl screws may stabilize the anterior ring to the body of C2. The role of this C1-2 fusion is not yet universally accepted, but with experience, the indications and role will be more clearly defined. A transoral resection of C1 may be preferred to an alternative technique, decompression posteriorly to the foramen magnum, particularly for a migrating odontoid fragment from an associated type 2 Anderson and D'Alonzo odontoid fracture with a Jefferson fracture. The significant amount of rotation of the atlas on the axis would be lost with this fusion, but the fusion would preserve the flexion and extension of the occipital condyle and head on the lateral masses, which would also be lost in an occipital C2 fusion, which is the traditional approach.

With regard to C1-to-C2 fixation, wires have been used for a significant time with excellent results. Gallie described fusion where wires are passed onto the arch of C1 and into the spinous process of C2.^[12] In 1978, Brooks and Jenkins then presented a more stable construct^[13] : Rather than placing the bone graft over the posterior elements, grafts are wedged between the posterior arch of C1 and C2, and the wires are passed under both C1 and C2, so they can more effectively stabilize the bone grafts in their respective positions and increase the area for fusion. However, this procedure requires passing the wires more laterally, with careful attention to the vascular structures.

In 2002, Richter et al presented 6 different techniques for biomechanical comparison, preferring transarticular screws but considering isthmic screws with a claw or lateral mass screws and isthmic screws as an alternative with somewhat less immediate stability.^[14] A 2003 report by Cornefjord et al on a series of patients with Olerud cervical fixation has also been presented^[15] : odontoid fracture occurred in 18 patients, rheumatoid instability in 6, and odontoid nonunion and os odontoideum in 1 patient each, with clinical follow-up (20 patients followed for 6-27 months) suggesting no serious complications and a high frequency of fusion healing.

The posterior arch at C1 has minimal bone for the fusion to heal, and claw techniques to avoid passing sublaminar wires over the brain stem had some early discouraging results, leading to refinements and further investigation. Various techniques will continue to be compared and studied because this is clearly a challenging area.