Cervical spine injury classification systems are essential to allow the precise description of fractures, which facilitates communication between physicians, determines prognosis, directs treatment, and assesses outcomes. The current systems are inadequate. Their reliability has not been tested, frequently are too complex, do not routinely measure the degree of instability, and generally fail to assess neurologic injury. A new proposed cervical spine injury severity score based on independent evaluation of the four spinal “columns” quantifies morphologic damage. It has excellent intraobserver reliability but needs validation for its measure of stability. Further investigations need to correlate this system to use of MRI and how it influences treatment decision-making.
Little new information is available regarding the diagnosis, treatment, and prognosis of patients with odontoid fractures. Anderson and D'Alonzo Type 1 fractures without atlanto-occipital displacement and Type 3 are generally treated nonoperatively. Controversies exist on whether these fractures are best treated using halo or collar. Type 2 injuries remain the most problematic with higher incidence of nonunion. Risk factors include displacement greater than 5 mm, comminution, increased age, and posterior displacement. Treatment alternatives are collar or cervicothoracic brace, halo-vest, posterior C1–C2 fusion with rigid fixation, and odontoid screw fixation. There is no consensus regarding which method is most efficacious. It is anecdotally observed that increased numbers of geriatric patients are having odontoid fracture. These elderly patients with a Type 2 odontoid fracture have a higher risk of complications including mortality. The morbidity of nonunion in this population is also not well defined. These patients should be treated using principles learned from caring of geriatric patients with hip fractures: rapid mobilization. In the case of odontoid fractures, patients can be mobilized rapidly in a collar or after surgical stabilization. Most authorities feel the halo-vest should be avoided in this population.
Historically, stabilization of the craniocervical and cervicothoracic junction was difficult because of inability to align anchor points to instrumentation, poor biomechanical performance, and inadequate radiographic visualization of these regions. Advances in internal fixation allow independent screw placement, rigid connections between screw connectors and longitudinal members, and ability to capture the anchor at any distance from the rod. Although these devices are easier to implant, there is no available Level I or II data that evaluate their efficacy. Safety of these implants is dependent on careful preoperative assessment of anatomy, especially the location of the vertebral artery in relation to the position of screws, meticulous technique, and use of proper radiologic imaging or navigation during surgery.