Spinal Cord Injuries
Dr Mohamed abdul jalil altamimi Consultant neurosurgeon Department of surgery 2015-2016Basic Anatomy and Physiology
What is the anatomy of the spinal cord on cross section?What is the anatomy of the spinal cord on cross section?
What are the clinically important ascending tracts and where do they cross over?What are the clinically important descending tracts and where do they cross over?
At what level does the spinal cord end and why is it important?
What are the differences between UMN and LMN? (e.g., cauda equina vs. myelopathy)
SPINAL TRAUMAAcute vs. chronic injuries; complete vs. incomplete injuries
“Acute”=sudden onset of symptoms“Complete” ?What is a complete spinal cord injury?
“Complete” = absence of sensory and motor function in the perianal area (S4-S5)Terminology
Plegia = complete lesion Paresis = some muscle strength is preserved Tetraplegia (or quadriplegia) Injury of the cervical spinal cord Patient can usually still move his arms using the segments above the injury (e.g., in a C7 injury, the patient can still flex his forearms, using the C5 segment) Paraplegia Injury of the thoracic or lumbo-sacral cord, or cauda equina Hemiplegia Paralysis of one half of the body Usually in brain injuries (e.g., stroke)Motor: how do you test each segment?
Motor: how do you grade the strength?
Sensory: how do you determine the level?
What are the important vegetative functions and when are they affected?Reflexes
Deep Tendon Reflexes Arm Bicipital: C5 Styloradial: C6 Tricipital: C7 Leg Patellar: L3, some L4 Achilles: S1 Pathological reflexes Babinski (UMN lesion) Hoffman (UMN lesion at or above cervical spinal cord) Clonus (plantar or patellar) (long standing UMN lesion)What is and how do you determine the level of injury?
Motor level = the last level with at least 3/5 (against gravity) function NB: this is the most important for clinical purposes Sensory level = the last level with preserved sensation Radiographic level = the level of fracture on plain XRays / CT scan / MRI NB: spine level does not correspond to spinal cord level below the cervical regionCase scenario
25 y/o white maleFell off the roof (20 feet)Had to be intubated at the scene by EMSConsciousness regained shortly thereafterCould not move arms or legsCould close and open eyes to commandNot able to breathe by himself–totally dependent on mechanical ventilationHigh cervical injuries (C3 and above)
Motor and sensory deficits involve the entire arms and legs Dependent on mechanical ventilation for breathing (diaphragm is innervated by C3-C5 levels)Case scenario
19 y/o white maleDiving accident (shallow water)No loss of consciousness Could not understand why he could not move his legs, forearms and hands (he could shrug shoulders and elevate arms)BP 75/40, HR 54/’Had difficulties breathing and required intubation a few hours after the accident
Midcervical injuries (C3-C5)
Varying degrees of diaphragm dysfunction Usually need ventilatory assistance in the acute phase ShockWhat is the difference between spinal shock and neurogenic shock?
NeurogenicHypovolemic
Etiology
Loss of sympathetic outflow
Loss of blood volume
Blood pressure
Hypotension
Hypotension
Heart rate
Bradycardia
Tachycardia
Skin temperature
Warm
Cold
Urine output
Normal
Low
Neurogenic shock
Seen in cervical injuries Due to interruption of the sympathetic input from hypothalamus to the cardiovascular centers Hallmark: hypotension (due to vasodilation, due to loss of sympathetic tonic input) is associated with bradycardia (not tachycardia, the usual response), due to inability to convey the information to the vasomotor centers in the spinal cord
Low cervical injuries (C6-T1)
Usually able to breathe, although occasionally cord swelling can lead to temporary C3-C5 involvement (need mechanical ventilation) The level can be determined by physical examSo what do you expect with a cervical lesion?
Quadriplegia or quadriparesis Bowel/bladder retention (spastic) Various degrees of breathing difficulties Neurogenic and/or spinal shockCase scenario
22 y/o femaleMotor vehicle accident (hit a pole at 60mph)Short term loss of consciousness (10’) Not able to move or feel her legsNo bladder / bowel control or sensationSensory level at the umbilicusThoracic injuries (T2-L1)
Paraparesis or paraplegia UMN (upper motor neuron) signsCase scenario
22 y/o female Motor vehicle accident Not able to move or feel her legs below the knee Could flex thighs against gravity No bladder / bowel control or sensation Sensory level above the knee on L, below the knee on RCauda equina injuries (L2 or below)
Paraparesis or paraplegia LMN (lower motor neuron) signs Thigh flexion is almost always preserved to some degree
What is the difference between cauda equina and conus medullaris syndrome?
What is an incomplete lesion?Anterior cord syndrome
Loss of motor, pain and temperature Preserved propioception and deep touchWhat is the central cord syndrome?
Cervical spinal cord involvement with arms more affected than legs May occur with trauma, tumors, infections, etc Traumatic lesions tend to improve in 1-2 weeks Surgical decompression may be indicated if there is spinal stenosisBrown-Sequard syndrome
Goal of spine trauma careProtect further injury during evaluation and management Identify spine injury or document absence of spine injury Optimize conditions for maximal neurologic recovery
Suspected Spinal Injury
High speed crash Unconscious Multiple injuries Neurological deficit Spinal pain/tenderness Up to 15% of spinal injuries have a second (possibly non adjacent) fracture elsewhere in the spine
Initial Management
Immobilization Rigid collar Sandbags and straps Spine board Log-roll to turn Prevent hypotension Pressors: Dopamine, not Neosynephrine Fluids to replace losses; do not overhydrate Maintain oxygenation O2 per nasal canula If intubation is needed, do NOT move the neckAdvance Trauma Life Support (ATLS) guidelinesManagement in the hospital
NGT to suction Prevents aspiration Decompresses the abdomen (paralytic ileus is common in the first days) Foley Urinary retention is common Methylprednisolone (Solu-Medrol) Only if started within 8 hours of injury Exclusion criteria Cauda equina syndrome GSW Pregnancy Age <13 years Patient on maintenance steroidsRadiolographic evaluation
X-ray Guidelines (cervical) AABBCDS Adequacy, Alignment Bone abnormality, Base of skull Cartilage Disc space Soft tissueAdequacy
Must visualize entire C-spine A film that does not show the upper border of T1 is inadequateCaudal traction on the arms may helpIf can not, get swimmer’s view or CTAlignment
The anterior vertebral line, posterior vertebral line, and spinolaminar line should have a smooth curve with no steps or discontinuities Malalignment of the posterior vertebral bodies is more significant than that anteriorly, which may be due to rotation A step-off of >3.5mm is significant anywhereLateral Cervical Spine X-Ray
Anterior subluxation of one vertebra on another indicates facet dislocation< 50% of the width of a vertebral body unilateral facet dislocation> 50% bilateral facet dislocationBones
Disc
Disc Spaces Should be uniform Assess spaces between the spinous processesSoft tissue
Nasopharyngeal space (C1) 10 mm (adult) Retropharyngeal space (C2-C4) 5-7 mm Retrotracheal space (C5-C7) 14 mm (children) 22 mm (adults)AP C-spine Films
Spinous processes should line up Disc space should be uniform Vertebral body height should be uniform. Check for oblique fractures.Open mouth view
Adequacy: all of the dens and lateral borders of C1 & C2 Alignment: lateral masses of C1 and C2 Bone: Inspect dens for lucent fracture linesCT scan
Good in acute situations Shows bone very well Sagittal reconstruction is mandatory Soft tissues (discs, spinal cord) are poorly visualized Do NOT give contrast in trauma patients (contrast is bright, mimicking blood)MRI
Almost never an emergency Exception: cauda equina syndrome Shows tumors and soft tissues (e.g., herniated discs) much better than CT scan May be used to clear c-spine in comatose patients
Lumbar Puncture
Sedate the patient and make your life easier Measure opening pressure with legs straight Always get head CT prior to LP to r/o increased ICP or brain tumorCervical Spine Clearance
Occiput to T1 need to be cleared ER, Neurosurgery or Orthopedics physician If the patient Is awake and oriented Has no distracting injuries Has no drugs on board Has no neck pain Is neurologically intact then the c-spine can be cleared clinically, without any need for XRays CT and/or MRI is necessary if the patient is comatose or has neck pain Subluxation >3.5mm is usually unstableCervical Traction
Gardner-Wells tongs Provides temporary stability of the cervical spine Contraindicated in unstable hyperextension injuries Weight depends on the level (usually 5lb/level, start with 3lb/level, do not exceed 10lb/level) Cervical collar can be removed while patient is in traction Pin care: clean q shift with appropriate solution, then apply povidone-iodine ointment Take XRays at regular intervals and after every move from bedJefferson Fracture
Burst fracture of C1 ring Unstable fracture Increased lateral ADI on lateral film if ruptured transverse ligament and displacement of C1 lateral masses on open mouth view Need CT scanBurst Fracture
Fracture of C3-C7 from axial loading Spinal cord injury is common from posterior displacement of fragments into the spinal canal UnstableClay Shoveler’s Fracture Flexion fracture of spinous process C7>C6>T1 Stable fracture