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Chapter Summary
• Context: Traumatic spinal cord injury (SCI) represents a devastating medical and surgical emergency combining mechanical disruption of neural pathways, acute vertebral instability, and profound systemic autonomic dysregulation. Pathophysiologically, SCI evolves in a two-phase cascade: the primary injury consists of immediate mechanical tissue disruption, axonal shearing, petechial microvascular hemorrhage, and localized ischemia at the moment of impact; this triggers a destructive secondary injury cascade evolving over subsequent hours and days, characterized by extensive microvascular vasospasm, blood-spinal cord barrier breakdown, cytotoxic and vasogenic edema, glutamate excitotoxicity, free radical lipid peroxidation, neuroinflammation, oligodendrocyte apoptosis, and expanding secondary ischemia. Clinical presentation ranges from complete transection (ASIA A) to incomplete spinal cord syndromes: Central Cord syndrome (greater motor weakness in upper than lower extremities), Brown-Séquard syndrome (ipsilateral motor/proprioceptive loss with contralateral pain/temperature loss), Anterior Cord syndrome (loss of motor and spinothalamic function with preserved dorsal column proprioception), Conus Medullaris syndrome, and Cauda Equina syndrome. Management requires immediate systemic neuroprotection: maintaining Mean Arterial Pressure (MAP >= 85–90 mmHg for 5–7 days), avoiding hypoxia (PaO2 > 60 mmHg), early surgical decompression and realignment (<24 hours, ideally <12 hours according to the STASCIS trial), and preventing systemic complications (neurogenic shock, autonomic dysreflexia, venous thromboembolism, neurogenic bladder/bowel, and pressure ulcers).
• Chapter Objective: To present current evidence-based principles for the evaluation, neuroprotection, surgical decompression, and comprehensive acute management of traumatic spinal cord injury. The reader should be able to understand the primary mechanical insult and secondary biochemical injury cascades; perform and document standardized neurological examinations according to ISNCSCI/ASIA standards; differentiate incomplete cord syndromes; execute hemodynamic optimization protocols (MAP targets); select candidates for urgent surgical decompression; and manage acute systemic complications and neurogenic shock.
• Primary Injury and the Secondary Pathophysiological CascadePrimary injury occurs at impact via contusion, compression, distraction, or laceration of neural tissue and microvasculature. Secondary injury develops over hours to weeks: 1) Vascular phase: petechial central gray matter hemorrhage, loss of autoregulation, vasospasm, and microthrombosis causing expanding ischemia; 2) Cellular phase: energy failure (ATP depletion), massive glutamate release, pathological intracellular calcium influx, and free radical generation (lipid peroxidation); 3) Inflammatory and apoptotic phase: neutrophil and macrophage infiltration, cytokine release (TNF-alpha, IL-1beta), and programmed cell death (apoptosis) of oligodendrocytes causing post-traumatic demyelination and secondary cord cavitation.
• Standardized Neurological Assessment (ISNCSCI/ASIA)Baseline examination must follow the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) as soon as the patient is alert and resuscitated: 1) Motor examination: test 10 key muscle groups bilaterally (MRC scale 0–5, total score 100); 2) Sensory examination: test 28 dermatomes bilaterally for pinprick and light touch (total score 112 each); 3) Anorectal examination: assess voluntary anal contraction (VAC, S4–S5 motor) and deep anal pressure (DAP, S4–S5 sensory). Define the Motor Level, Sensory Level, and Neurological Level of Injury (NLI). Classify using the ASIA Impairment Scale (AIS): AIS A (Complete, no sacral sparing S4–S5); AIS B (Sensory Incomplete, sensory but no motor preserved below NLI including S4–S5); AIS C (Motor Incomplete, more than half of key muscles below NLI have muscle grade <3); AIS D (Motor Incomplete, at least half of key muscles below NLI have muscle grade >=3); AIS E (Normal).
• Incomplete Cord Syndromes and Neurogenic ShockIncomplete syndromes feature specific tract injury patterns: 1) Central Cord Syndrome: hyperextension injury in stenotic cervical spines, causing disproportionately greater upper extremity weakness (distal hand intrinsics) than lower extremity impairment, with variable sensory loss; 2) Brown-Séquard Syndrome: hemisection from penetrating or burst trauma, causing ipsilateral loss of motor function and proprioception/vibration with contralateral loss of pain and temperature 1–2 segments below injury; 3) Anterior Cord Syndrome: flexion-compression injury with anterior spinal artery occlusion, causing complete bilateral motor paralysis and loss of pain/temperature with preserved dorsal column proprioception (worst recovery prognosis). Neurogenic shock (cervical/high-thoracic T6 and above injury) is characterized by the triad of hypotension, bradycardia, and peripheral vasodilation due to loss of sympathetic tone, distinct from spinal shock (transient loss of all spinal reflex activity and flaccidity below injury level, ending when the bulbocavernosus reflex returns).
• Hemodynamic Neuroprotection and Surgical Timing (STASCIS)Hemodynamic management aims to prevent secondary ischemic cord injury: maintain Mean Arterial Pressure (MAP) between 85 and 90 mmHg for 5 to 7 days in the ICU using volume resuscitation and vasopressors with combined inotropic and vasoconstrictive properties (norepinephrine, dopamine, or epinephrine; avoid pure vasoconstrictors like phenylephrine that worsen bradycardia). Surgical decompression and rigid stabilization within 24 hours (and ideally within 12 hours) of injury—supported by the landmark STASCIS prospective trial and subsequent pooled analyses—significantly increases the likelihood of >=2 AIS grade neurological recovery compared to delayed decompression (>24 hours).
• Pharmacotherapy, Complications, and Acute RehabilitationHigh-dose methylprednisolone (NASCIS protocol) remains highly controversial; modern international guidelines (AANS/CNS and AO Spine) consider it a treatment option rather than a standard of care due to high risks of severe pneumonia, sepsis, GI bleeding, and death. Systemic management includes: early venous thromboembolism prophylaxis (LMWH started 24–48 hours post-injury/surgery and mechanical compression), aggressive pulmonary toilet and mechanical ventilation weaning, clean intermittent catheterization to avoid bladder distension and dysreflexia, bowel protocols, and pressure-relieving air mattresses.
• Clinical Application: In the emergency department, when a patient presents with cervical trauma and acute quadriparesis, immediately obtain emergent whole-spine CT and urgent MRI to demonstrate compressive bone fragments, disc herniation, or facet subluxation. Simultaneously initiate invasive arterial line monitoring and titrate norepinephrine to maintain MAP between 85 and 90 mmHg. In patients with bilateral facet dislocations, prompt closed skeletal traction with Gardner-Wells tongs (under conscious sedation with continuous neurological monitoring) or emergent operative open reduction within hours restores canal dimensions and cord perfusion. Transfer the patient to the operating room immediately for definitive anterior, posterior, or circumferential decompression and instrumented fusion (<12–24 hours). In patients with high lesions (T6 and above), remain vigilant for autonomic dysreflexia (paroxysmal severe hypertension, throbbing headache, bradycardia, profuse sweating above lesion triggered by bladder distension or fecal impaction), treating it by sitting the patient upright and rapidly emptying the bladder or bowel.
