Epidemiology Incidence 11,000 new cases/year in US 34% incomplete tetraplegia central cord syndrome most common 25% complete paraplegia 22% complete tetraplegia 17% incomplete paraplegia Demographics bimodal distribution young individuals with significant trauma older individuals that have minor trauma compounded by degenerative spinal canal narrowing Anatomic location 50% in cervical spine Etiology Mechanism MVA causes 50% falls GSW iatrogenic it is estimated that 3-25% of all spinal cord injuries occur after initial traumatic episode due to improper immobilization and transport. Pathophysiology primary injury damage to neural tissue due to direct trauma irreversible secondary injury injury to adjacent tissue due to decreased perfusion lipid peroxidation free radical / cytokines cell apoptosis methylprednisone used to prevent secondary injury by improving perfusion, inhibiting lipid peroxidation, and decreasing the release of free radicals Associated conditions acute phase conditions (see below) spinal shock neurogenic shock associated injuries closed head injuries noncontiguous spinal fractures vertebral artery injury risk factors for vertebral artery injury include atlas fractures facet dislocations most people with unilateral injury remain asymptomatic imaging magnetic resonance angiography is least invasive method treatment stenting only if patient is symptomatic from basilar arterial insufficiency Relevant Anatomy See Spinal Cord Anatomy Classification Descriptive tetraplegia injury to the cervical spinal cord leading to impairment of function in the arms, trunk, legs, and pelvic organs paraplegia injury to the thoracic, lumbar or sacral segments leading to impairment of function in the trunk, legs, and pelvic organs depending on the level of injury. Arm function is preserved complete injury an injury with no spared motor or sensory function below the affected level. patients must have recovered from spinal shock (bulbocavernosus reflex is intact) before an injury can be determined as complete classified as an ASIA A incomplete injury an injury with some preserved motor or sensory function below the injury level incomplete spinal cord injuries include anterior cord syndrome Brown-Sequard syndrome central cord syndrome posterior cord syndrome conus medullaris syndromes cauda equina syndrome ASIA Classification ASIA Impairment Scale Motor Sensory A Complete No motor function Complete deficit B Incomplete No motor function Incomplete deficit C Incomplete Motor function partially preserved: more than half of key muscles below the neurological level have a muscle grade less than 3. Incomplete deficit D Incomplete Motor function is partially preserved - at least half of key muscles below the neurological level have a muscle grade of 3 or more. Incomplete deficit E Normal Normal motor Normal sensory Acute Phase Conditions Neurogenic shock characterized by hypotension & relative bradycardia in patient with an acute spinal cord injury potentially fatal mechanism circulatory collapse from loss of sympathetic tone disruption of autonomic pathway within the spinal cord leads to lack of sympathetic tone decreased systemic vascular resistance pooling of blood in extremities hypotension treatment Swan-Ganz monitoring for careful fluid management pressors to treat hypotension Spinal shock defined as temporary loss of spinal cord function and reflex activity below the level of a spinal cord injury. characterized by flaccid areflexic paralysis bradycardia & hypotension (due to loss of sympathetic tone) absent bulbocavernosus reflex reflex characterized by anal sphincter contraction in response to squeezing the glans penis or tugging on an indwelling Foley catheter timing variable but usually resolves within 48 hours at its conclusion spasticity, hyperreflexia, and clonus slowly progress over days to weeks mechanism neurophysiologic in nature neurons become hyperpolarized and unresponsive to stimuli from brain evaluation important because one cannot evaluate neurologic deficit until spinal shock phase has resolved end of spinal shock indicated by return of the bulbocavernous reflex conus or cauda equina injuries may lead to permanent loss of the bulbocavernous reflex ruled out when bulbocavernous reflex present 48 hours has elapsed from time of injury stages of spinal shock Phase 1 - hyporeflexic 0 to 48 hours areflexia/hyporeflexic Phase 2 - initial reflex return 1-2 days polysynaptic reflexes return (bulbocavernous reflex) monosynaptic (patellar) remain absent Phase 3 - initial hyperreflexia 1-4 weeks Phase 4 - spasticity 1 to 12 months characterized by altered skeletal performance Spinal vs. Neurogenic vs. Hypovolemic Shock Spinal shock Neurogenic shock Hypovolemic shock BP Hypotension Hypotension Hypotension Pulse Bradycardia Bradycardia Tachycardia Reflexes / Bulbocavernosus Reflex Absent Variable/independent Variable/independent Motor Flaccid Paralysis Variable/independent Variable/independent Time ~48-72 hours immediately after spinal cord injury ~48-72 hours immediately after spinal cord injury Following excessive blood loss Mechanism Peripheral neurons become temporarily unresponsive to brain stimuli. Disruption of autonomic pathway leads to loss of sympathetic tone and decreased systemic vascular resistance. Decreased preload leads to decreased cardiac output. Evaluation Field treatment treatment of potential spinal cord injuries begins at the accident scene with proper spinal immobilization immobilization immobilization should include a rigid cervical collar and transport on a firm spine board with lateral support devices patient should be rolled with standard log roll techniques with control of cervical spine spine boards should be used for transport only and patients should be removed when clinically safe decubitus ulcers can occur after only 30-60 mintues on a backboard athletes in the setting of sports-related injuries helmets and shoulder pads should be left on until arrival at the hospital OR until experienced personnel can perform simultaneous removal of helmet and shoulder pads in a controlled situation Initial evaluation primary survey airway breathing SCI above C5 likely to require intubation circulation initial survey to inspect for obvious injuries of head and spine visual and manual inspection of entire spine should be performed seat belt sign (abdominal ecchymoses) should raise suspicion for flexion distraction injuries of thoracolumbar spine secondary survey cervical spine exam remove immobilization collar examine face and scalp for evidence of direct trauma inspect for angular or rotational deformities in the holding position of the patient's head rotational deformity may indicate a unilateral facet dislocation palpate posterior cervical spine looking for tenderness along the midline or paraspinal tissues absence of posterior midline tenderness in the awake, alert patient predicts low probability of significant cervical injury log roll patient to inspect and palpate entire spinal axis perform careful neurologic exam cervical spine clearance Initial Medical Treatment Medical / Prevention DVT prophlaxis indications most patients contraindications include coagulopathy hemorrhage modalities low-molecular weight heparin rotating bed pneumatic compression stocking cardiopulmonary management careful hemodynamic monitoring and stabilization is critical in early treatment hypotension should be avoided implement immediate aggressive pulmonary protocols decubitus ulcer prevention Steroids high dose methylprednisone indications current indications current literature and available guidelines recommend against administration due to lack of clear clinical benefit risk of complications historical indications nonpenetrating SCI within 8 hours of injury recommended by NASCIS III historical contraindications include GSW pregnancy under 13 years > 8 hours after injury brachial plexus injuries (peripheral nerve injuries) technique load 30 mg/kg over 1st hour (2 grams for 70kg man) drip 5.4 mg/kg/hr drip for 23 hours if started < 3 hrs after injury for 47 hours if started 3-8 hours after injury outcomes may leads to improved root function at level of injury associated with significant complications monosialotetrahexosylganglioside (GM-1) indications remains controversial large multicenter RCT did not show long term benefit some evidence of faster recovery Reduction acute closed reduction with axial traction indications alert and oriented patient with neurologic deficits and compression due to fracture/dislocation bilateral facet dislocation with spinal cord injury in alert and oriented patient is most common reason to perform acute reduction with axial traction technique reasons to abort overdistraction worsening neurologic exam failure to obtain reduction Hypothermia systemic and local evidence is weak and limited currently not recommended due to increased complications coagulopathy sepsis pneumonia rebound hypertension arrhythmias Definitive Treatment Nonoperative bracing and observation indications most GSWs exceptions listed below Operative surgical decompression and stabilization indications most incomplete SCI (except GSW) decompress when patient hits neurologic plateau or if worsening neurologically decompression may facilitate nerve root function return at level of injury (may recover 1-2 levels) most complete SCI (except GSW) stabilize spine to facilitate rehab and minimize need for halo or orthosis decompression may facilitate nerve root function return at level of injury (may recover 1-2 levels) consider for tendon transfers e.g. Deltoid to triceps transfer for C5 or C6 SCI GSW with progressive neurological deterioration with retained bullet within the spinal canal cauda equina syndrome (considered a peripheral nerve) retained bullet fragment within the thecal sac CSF leads to the breakdown of lead products that may lead to lead poisoning Rehabilitation Goals goal is to assess and identify mechanisms for reintegration into community based on functional level and daily needs patients learn transfer techniques, self care retraining, mobility skills Restoring hand function hand function is often limiting factor for many patients tendon transfers can be used to restore function to paralyzed arms and hands by giving working muscles different jobs Modalities functional electrical stimulation is a technique that uses electrical currents to stimulate and activate muscles affected by paralysis Spinal cord injury level and Function Level Patient Function C1-C3 Ventilator-dependent with limited talking. Electric wheelchair with head or chin control C3-C4 Initially ventilator-dependent, but can become independent Electric wheelchair with head or chin control C5 Ventilator independent Has biceps, deltoid, and can flex elbow, but lacks wrist extension and supination needed to feed oneself Independent ADL’s; electric wheelchair with hand control, minimal manual wheelchair function C6 C6 has much better function than C5 due to ability to bring the hand to mouth and feed oneself (wrist extension and supination intact) Independent living; manual wheelchair with sliding board transfers, can drive a car with manual controls C7 Improved triceps strength Daily use of a manual wheelchair with independent transfers C8-T1 Improved hand and finger strength and dexterity Fully independent transfers T2-T6 Normal UE function Improved trunk control Wheelchair-dependent T7-T12 Increased abdominal muscle control Able to perform unsupported seated activities; with extensive bracing walking may be possible L1-L5 Variable LE and B/B function Assist devices and bracing may be needed S1-S5 Various return of B/B and sexual function Walking with minimal or no assistance Prognosis Complete Injuries improvement of one nerve root level can be expected in 80% of patients improvement of two nerve root levels can be expected in 20% of patients only 1% have complete recovery at time of hospital diagnosis ASIA A injuries have the least chance for marked recovery and the highest lifetime healthcare costs Incomplete Injuries trends of improvement include the greater the sparring, the greater the recovery patients that show more rapid recovery have a better prognosis when recovery pleateus, it rarely resumes improvement Conus medullaris syndrome has a better prognosis for recovery than more proximal lesions Complications Skin problems treatment is prevention start in ER do not leave on back board start log rolling early proper bedding Venous Thromboembolism prevent with immediate DVT prophylaxis Urosepsis common cause of death strict aseptic technique when placing catheter don't let bladder become overly distended Sinus bradycardia most common cardiac arrhythmia in acute stage following SCI Orthostatic hypotension occurs as a result of lack of sympathetic tone Autonomic dysreflexia potentially fatal presents with headache, agitation, hypertension caused by unchecked visceral stimulation check foley disimpact patient radiographs of lower extremity if there is concern for undiagnosed fracture Major depressive disorder ~11% of patients with spinal cord injuries suffer from MDD MDD in spinal cord injury patients is highly associated with suicidal ideation in both the acute and chronic phase. Prognosis Only 1% have complete recovery at time of hospital diagnosis conus medullaris syndrome has a better prognosis for recovery than more proximal lesions