Chapter 6 Spine emergencies
Orthopedic Emergencies, ed. Michael C. Bond, Andrew D. Perron, and Michael K. Abraham. Published by Cambridge University Press. © Cambridge University Press 2013.
Acute spine injuries: Cervical, thoracic, and lumbar spine fractures and the spine-injured patient
Key facts
The initial evaluation of spine injuries in a trauma patient is of obvious importance, as a missed injury can cause permanent and devastating neurologic injuries
Spinal cord and spinal column injuries are typically seen in two age groups and with two different mechanisms. High-energy mechanisms in the younger patient population, and lower-energy mechanisms in older patients with ankylosed spines, or those at risk of fragility fractures
Closed head injuries and facial trauma should prompt a work-up for a cervical spine injury, as it implies that the cervical spine was also subjected to a great deal of force
If a single spinal fracture is identified, potential spinal injuries at other levels should be evaluated
Evaluation and management
Protocols and systems to immobilize patients at the scene, protect the spine, and provide safe extrication and transport to the emergency department have increased survival in the spine-injured patient, and reduced the number of neurologic injuries
Poor immobilization and handling of patients have been shown to result in further neurologic injury after the initial accident or insult
Patient immobilization during transport should consist of a rigid cervical collar, lateral supports, and securing the patient to a backboard with tape and body supports
Young children are the exception, owing to the fact that their heads are disproportionately larger than their bodies. They should not be positioned flat on a backboard as this can cause anterior translation and flexion of a cervical injury. In order to accommodate this anatomic variation the backboard needs to be equipped with an occipital recess or a mattress placed beneath the torso and backboard
Patients with ankylosing spondylitis also require special attention be paid to positioning during transport. These patients often have a fixed kyphotic deformity of the spine. This posture should be respected and maintained during transport. The patient’s head may need to be supported with several pillows
Prolonged unnecessary immobilization can lead to increased morbidity in the form of pressure sores and other ailments; patients should be removed from the backboard in a timely fashion, and cervical collars should be removed as soon as a cervical injury is ruled out
Emergency evaluation: ABCDE
Airway: The cervical spine must be maintained in a stable position while managing the airway in a trauma patient. In-line immobilization with the cervical spine in a neutral position during direct laryngoscopy and orotracheal intubation is the preferred method
PEARL: Manual in-line traction has fallen out of favor because of the potential of distracting a cervical spine injury, especially one at the occipitocervical junction. In-line immobilization is preferred, and should not consist of any traction being applied to the cervical spine.
Breathing: Patients who experience a spinal cord injury at or above C3 typically require emergent intubation at the scene secondary to respiratory distress. Patients with signs of impeding respiratory failure should be pre-emptively intubated
Circulation: Hypotension, if present, should be assumed to be a result of hemorrhagic shock, and a search for the source of bleeding should follow. Initial treatment involves aggressive fluid resuscitation and vasopressors, as needed
PEARL: Seat-belted patients who present with a thoracolumbar flexion distraction injury should be evaluated for intra-abdominal trauma, including a blunt aortic injury.
Neurogenic shock: Classically presents with hypotension in the setting of bradycardia. It occurs in roughly 20% of patients with cervical spine trauma, and is the result of disruption of the sympathetic tone of the peripheral vasculature and the heart
PEARL: Neurogenic shock is classically seen in patients with spinal cord injury above T4.
Disability and exposure: A log roll should be performed during the secondary survey. Tenderness, swelling, bruising or a step-off deformity may be signs of a spine injury. A digital rectal exam and assessment of the patients rectal tone is an essential part of the neurologic assessment and the general trauma evaluation
PEARL: Lower-extremity injuries such as calcaneal, pilon, or tibial plateau fractures that result from axial loading should prompt the physician to evaluate the spine for a thoracolumbar burst fracture.
Neurologic evaluation (Tables 6.1, 6.2, 6.3)
In the acute setting the neurologic assessment is performed in accordance with the international standards for the Neurologic Classification of Spinal Cord Injury, formerly the ASIA (American Spinal Injury Association) standards
Motor examination: Measures the strength of five upper and five lower-extremity myotomes on a grading scale of 0–5, established by the Medical Research Council
Sensory examination: Performed by evaluating light touch and pinprick sensation in 28 dermatomes. Sensation is either absent, impaired or normal and scored 0, 1, 2 respectively
Reflexes: in patients with spinal cord injuries reflexes are usually absent initially and the limbs are flaccid. Reflexes will become hyperreflexic later in the course of spinal cord injury
A Babinski response, when pathologic, is associated with upper motor neuron dysfunction. The reflex is elicited by stroking the lateral plantar surface of the foot with a semi-sharp object. A pathologic response will be noted by extension of the great toe with flexion and spreading of the lateral toes
A bulbocavernosus reflex is performed by tugging on the bladder catheter or stimulating the glans or clitoris and evaluating whether reflex anal contraction occurs
Spinal shock: A temporary state of the acutely injured spinal cord marked by loss of reflex function below the level of the injury. This typically lasts from 24 to 48 hours, and the end is marked by the return of reflexes, including the bulbocavernosus reflex. Technically speaking the diagnosis of a complete spinal injury can not be made until spinal shock resolves
PEARL: If light touch or pinprick sensation is present in any form at S4–5, or if any anal sensation or contraction is present, the patient has an incomplete spinal cord injury.
Sensory level: The most distal level with normal sensation to pinprick and light touch
Motor level: The most distal level with intact innervation; below this level there are motor deficits
PEARL: The most distal muscle to have grade-3 strength or higher is considered to be fully innervated because of muscle polyinnervation.
Initial radiographic evaluation in the spine trauma patient
The NEXUS and Canadian C-spine rules are utilized to help the practitioner exclude a C-spine injury without the use of radiographs
Asymptomatic patients with the following criteria do not require radiographs:
Fully awake, alert and co-operative
Involved in a low-energy trauma
Neurologically intact
No mid-line tenderness
Can actively rotate his/her head 45°
No distracting injuries
PEARL: Patients with neck pain, tenderness to palpation, and obtunded patients require radiographic evaluation. Patients with distracting injuries should be placed on spine precautions until their other injuries are addressed.
At most institutions CT has replaced conventional radiographs as the imaging modality of choice for evaluating potential spine injuries
MRI is the study of choice for evaluating ligamentous injuries, neural element trauma and compression, and disc herniations
PEARL: Not all abnormal findings on MRI are clinically significant; MRI has the tendency to “over-read” injury to the posterior ligamentous structures in the cervical and thoracolumbar spine.
Both CT and MRI may be needed to clear the cervical spine in an obtunded patient
Special patient population: Ankylosing spondylitis and diffuse idiopathic skeletal hyperostosis (DISH)
Recognizing patients with ankylosing spondylitis and DISH is of paramount importance when evaluating for a potential spine injury
These patients can suffer fractures and devastating neurologic injuries as a result of even low-energy trauma
This patient population can experience rapid neurologic deterioration if their fracture is not identified or if treatment of their fracture is delayed
Typical guidelines for determination of spinal stability do not apply to this patient population, and deeming a fracture stable because there is no displacement is a grave error
PEARL: In patients with ankylosing spondylitis or DISH who present with neck or back pain the assumption should be made that they have suffered a fracture. Advanced imaging such as a CT or MRI is mandatory.
Emergency management of the spine-injured patient
If an injury is identified, the spine must be protected until definitive management is provided (e.g., rigid cervical orthosis for patients with a cervical spine fracture and maintenance of spine precautions)
If a patient has an occipitocervical dissociation, immediate application of a halo is recommended given the highly unstable nature of the injury
The administration of high-dose steroids in patients with an acute spinal cord injury is controversial and is not the standard of care
Management of blood pressure has been recognized as a neuroprotective strategy, and protocols that aim to keep mean arterial blood pressure above 85 to 90 mm Hg for 5–7 days with aggressive volume resuscitation and vasopressors have shown improved neurologic outcomes