Spine/Spinal Cord Injuries
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- Annually, there are approximately 10,000 people who sustain spinal cord injuries and 5% of patients with severe head injuries have an associated spinal cord injury.
- The three most common mechanisms of injury are: (1) blunt trauma secondary to motor vehicle accidents (90%), (2) falls and (3) gunshot wounds.
Cervical Spine Injuries
- Cervical spine injuries are uncommon but potentially lethal/debilitating.
- The NEXUS study has described the epidemiology of cervical spine injuries.
- 2.4% of over 34,000 patients enrolled in this study had cervical spine injuries.
- Patients are considered low risk for cervical spine injury and therefore do not need radiographic studies of the c-spine if: they have no evidence of intoxication, no posterior midline tenderness, no altered level of alertness, no distracting painful injury and normal neurologic function.
Evaluation
- Clinical assessment includes a complete neurologic assessment and evaluation of the presence/absence of NEXUS low risk criteria.
- Radiological evaluation should include three views of the c-spine.
- The lateral view needs to include from C1 to the C7/T1 interface. This view will demonstrate approximately 90% of all c-spine injuries.
- Complete three-view series (AP, lateral, and odontoid) will demonstrate 98% of injuries.
- CT scans or MRI should be used as needed to evaluate patients with continued tenderness despite normal X-rays.
Unstable Cervical Spine Injuries
- All cervical spine fractures are important, but special emphasis needs to be placed on unstable injuries.
- Odontoid fractures
- Mandibular fracture
- Type 2 and 3 odontoid fractures (base of the odontoid process and involving the body of C2)
- Jefferson’s fracture
- Vertical compression injury
- Lateral displacement of the lateral masses of C2
- Widening of the predental space seen on the lateral view. This space is normally < 3 mm in adults and < 5 mm in children.
- Bifacial injuries
- Flexion injury
- Anterior displacement more than 50% of the AP diameter of the vertebral body above the level of the injury
- Hangman’s injuries
- Hyperextension injury
- Fracture of the bilateral pedicles of C2
- Flexion teardrop fracture
- Hyper flexion injury
- Wedge-shaped fracture of the antero-inferior portion of the vertebral body.
- Any fracture dislocation
Anterior Cord Syndrome
Etiology
- This syndrome occurs as a result of severe flexion with injury to the spin thalamic and corticospinal tracts with sparing of the posterior columns.
Symptoms
- Generally, there is variable loss of motor function, pain and temperature sensation below the level of the lesion with preservation of the posterior columns (proprioception, vibration and light touch).
- Bilateral spastic paresis (lateral corticospinal tract)
- Bilateral loss of pain and temperature sensation (lateral spin thalamic tract)
- Bilateral flaccid paralysis (anterior horn).
- Bilateral Horner’s syndrome (hypothalamospinal tract T2 or above)
Prognosis
- Of incomplete spinal cord injuries, this syndrome carries the poorest prognosis.
- Patients may have partial recovery of sensory function; however, only 10-20% regains functional motor control.
Central Cord Syndrome
Etiology
- This syndrome usually occurs due to hyperextension or hyper flexion injuries in patients with preexisting cervical spine disease.
- The central spinal cord is most affected and often involves the corticospinal and spin thalamic pathways.
Symptoms
- Motor weakness is most pronounced in the upper extremities and in the distal portion of the extremities.
- There may be a variable sensory loss (pain/temperature more than proprioception/ vibration).
- Dysesthesias (e.g., a burning sensation in the hands or arms) are common.
- Bowel and bladder control is usually intact with sacral sensory sparing as the neural pathways controlling these functions are distributed laterally.
Prognosis
- Generally, the prognosis for central cord syndrome is good.
- For patients sustaining spinal cord contusion without hematomyelia, 50% recover enough to allow independent walking.
- However, patients have variable recovery of upper extremity function typically with poor fine motor control.
Brown-Sequard Syndrome
Etiology
- This syndrome is characterized by transverse hemi section of the spinal cord.
- The lesion is typically in the cervical region and may occur as a result of either a penetrating injury or blunt trauma.
- Other causes include: spinal cord tumors (unilateral cord compression), ischemia, herniated disk, hemorrhage or infectious or inflammatory diseases.
Symptoms
- Ipsilateral loss of proprioception, vibratory and tactile discrimination (posterior columns)
- Contralateral loss of temperature and pain sensation (lateral spin thalamic tract)
- Ipsilateral Babinski and spastic paralysis (lateral corticospinal tract)
Prognosis
- Of incomplete spinal cord injuries, this syndrome carries the best prognosis with 90% of patients recovering bowel and bladder control as well as the ability to independently ambulate.
Cauda Equina Syndrome
Etiology
- The cauda equina is made up of lumbar, sacral and coccygeal nerve roots.
- This syndrome is characterized by lumbosacral nerve root injury often as a result of a central lumbar disc herniation.
Symptoms
- Patients may experience a variable loss of motor and sensory function in the lower limbs; affected limbs are areflexic due to nerve root injury.
- The patient may also have areflexic bowel and/or bladder and saddle anesthesia (loss of pain sensation over the perineal area).
Prognosis
- This syndrome carries a much better prognosis than spinal cord injuries since peripheral nerves (i.e., lower motor neurons) have a greater regenerative capacity.
Conus Medullaris Syndrome
Etiology
- This syndrome occurs as a result of sacral cord injury with or without lumbar nerve root involvement.
Symptoms
- Patients typically experience variable loss of motor and sensory function in the lower limbs with areflexic bowel and/or bladder.
Prognosis
- In severe lesions, patients may experience pronounced bowel and bladder dysfunction.
Spinal Shock
Etiology
- Spinal shock is a transient condition appearing soon after injury with recovery typically seen in the first 24 h.
- This condition occurs after complete or partial injury at spinal cord level T6 or above.
Symptoms
- There are no reflexes or voluntary movements below the level of the injury.
- Patients may also experience sensory loss or loss of rectal tone.
- Autonomic dysfunction (hypotension, bradycardia and vasodilatation) is often seen.
SCIWORA
- Spinal cord injury without radiographic abnormality (SCIWORA) is typically seen in children and occurs in approximately 66% of youngsters with spinal cord injuries.
- Due to the increased flexibility of the immature spine and spinal column.
Radiographic Studies for Potential Spinal Injuries
- AP, lateral and odontoid cervical films
- The lateral film is useful as a screening tool since it identifies approximately 90% of cervical injuries
- It must include the C7-T1 junction in order to be an adequate study.
- CT scan
- A CT scan is useful if:
- There is any abnormality on plain film,
- If the patient has a neurological deficit with normal plain films
- Or if adequate visualization cannot be obtained with repeated plain films.
- MRI
- MRI is an increasingly important modality for visualizing ligament us injuries and evaluating the spinal cord and canal.
- It is also useful in detecting soft tissue, muscular or neurologic damage, but is less sensitive than CT for detecting bony injuries.
Treatment of Spinal Cord Injuries
- All spinal injuries are treated with strict maintenance of spinal immobilization.
- The National Acute Spinal Cord Injury Study (NASCIS II and III) trials demonstrated significant improvement in both motor and sensory function in patients with spinal cord injury when treated with methylprednisolone within 8 h of the injury.
- Orthopedic and neurosurgical consultation should be obtained as needed (Table 16.2).
- Intravenous antibiotics should be given in the emergency department to those patients with penetrating spinal cord injuries.
Table Treatment priorities for patients with spinal cord injuries
Prehospital—spine stabilization and immobilization
Primary and Secondary Survey
- ABCs
Indications for intubation of patients with spinal cord injury:
Decreased mental status (Glasgow Coma Scale <8)
Acute respiratory failure (e.g., fatigue, PCO2 >50 etc.)
- Supplemental oxygen
High dose steroids within 8 h of the injury for all patients with spinal cord injuries:
- Methylprednisolone 30 mg/kg over 15 min then…
If 0-3 h after the injury…45 min after the bolus, start a methylprednisolone infusion at 5.4 mg/kg per h for 24 h
OR
If 3-8 h after the injury…45 min after the bolus, start a methylprednisolone infusion at 5.4 mg/kg per h for 48 h
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