Spinal Injuries

Spinal injuries are seen in most road traffic accidents, fall injuries, or direct impacts. Vertebral fractures with or without spinal cord injuries should be assessed for proper management and to prevent long-term complications.

Spinal Cord brief anatomy

• 35% of the canal at the level of the atlas (C1)

• 50 % of the canal at the level of the lower cervical and lumbar region

• Spinal cord injuries: Injuries to the spine from cervical vertebrae to the thoracolumbar junction

• Below this cauda-equina begins

Reflex arc: Simple sensory-motor pathway that can function without either ascending and descending white matter- long tract axons

Primary Spinal Injuries:

1. Contusion
2. Compression
3. Stretch
4. Laceration

Secondary Spinal injuries:

• Additional neural tissue damage resulting from the biological response initiated by physical tissue disruption
• Change in local blood flow
• Tissue edema
• Metabolic concentrate
• The concentration of chemical mediators

These all lead to the propagation of interdependent reactions

Three common patterns of noncontiguous spinal injuries

1. Pattern A: Primary injury @ C5-C7 with secondary injury @T12/lumbar spine
2. Pattern B: Primary injury@T2-T4 with secondary injury @cervical spine
3. Pattern C: Primary injury@T12-L2 with secondary injury @L4-L5

Spinal Shock

“refers to flaccid paralysis, areflexia, and lack of sensation to physiological spinal cord “shut down” in response to injury”

Temporary electric dysfunction

‘Spinal cord dysfunction based on physiological rather than structural disruption’

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Resolution of spinal shock

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Reflex arc caudal to the level of injury begins to function again (within 24-48 hr of injury)

Most common in cervical and upper thoracic injury

‘Bulbocavernous reflex’ is 1^st to shut down

Differences between Neurogenic shock and hypovolemic shock

	Neurogenic Shock	Hypovolemic shock
Etiology	Loss of sympathetic outflow	Loss of circulating blood flow
B.P.	Hypotension	Hypotension
H.R.	Bradycardia	Tachycardia
Temp.	Warm extremities	Cold Extremities
Urinary output	Normal	Low

Bulbocavernous reflexs:

Contraction of an anal splinter in response to squeezing of the glans penis in the male, the clitoris/mons pubis in female, or pull of the urethral catheter.

Return of reflex activity:

Indicates spinal shock has passed off and remaining paralysis and anesthesia may be d/t injury to long tracts of cauda equina.

Total sensory and motor paralysis after 8 hr with the return of reflex activity indicates that the distal part of the spinal cord has been separated from cerebral control.

If no return with/in 24hr-10 days diagnosis of cervical cord transaction is made.

Conus medullaris:

• Seen in T12-L1 injuries
• caudal termination of the spinal cord
• Contains sacral and coccygeal myelomeres and lies dorsal to L1 body and L1-L2 IVD
• Loss of voluntary bowel and bladder control (S2- S4 parasympathetic control) with preserved lumber root function
• May be complete/ incomplete—>bulbo-caverbous reflex may be permanently lost

Cauda Equina:

• Motor and sensory roots of lumbosacral myelomeres
• Less likely to get injured
• Details on cauda equina

Posterior cord syndrome (rare):

• Motor power, deep pressure, pain, and proprioception lost

Incomplete Cord injury syndrome:

• Persistence of any sensation distal to the injury —>peri-anal pinprick is most imp.

Central cord syndrome:(most common)

• The initial flaccid weakness followed by
• LMN paralysis—>upper limb
• UMN (spastic) paralysis—> Lower limb

Sacral Sparing

Bladder control may/may not preserve

Anterior Cord Syndrome:

• Complete paralysis (corticospinal + spinothalamic) and anesthesia
• Dorsal column sparing (deep pressure and position sense retained in lower limb)

Brown Sequard Syndrome:

• d/t cord hemisection
• penetrating thoracic injury
• Loss of motor power + proprioception and light touch on the side of injury
• Loss of pain and temp sensation on the opposite side.

Classification of spinal injuries

1. Complete:
   1. No sensory /motor function noted caudal to the level of injury in (+) or intact bulbocavernosus reflex
   1. Reflex remains below the level of cord injury
2. Incomplete:
   1. Some neurological functions persist caudal to the level of injury after the return of bulbocavernosus reflex
   1. Greater the function distal to the lesion and faster recovery —> better prognosis
3. Transient spinal cord dysfunction

Sacral Sparing:

Perianal sensation+ voluntary rectal motor function+great toe flexor activity

Indicated continuity of white matter long tracts (corticospinal and spinothalamic)

Implied continuity between the cerebral cortex and lower sacral motor neurons

Clinical Classification of neurological damage:

1. Complete paralysis

2. Sensory paralysis

3. Motor Paralysis useless

4. Motor paralysis useful

5. Recovery

Injuries at

• Cervical Level:
  • Concussion to root injuries
  • Incomplete/ complete cord transaction
• Thoracic Level:
  • Paraplegia
• Thoraco-lumbar region:

3 things can occur

• Complete cord division and nerve intact
• Complete cord division and partial nerve division
• Complete cord division and complete nerve division

Level of Injury:

The grading system for Spinal cord injury [SCI]

Grading spinal cord injuries is important in planning treatment, analyzing the outcome, and knowing the prognosis following injury.

Frankel classifications:

ASIA impairment scale:

As per ASIA definition, neurological injury level is the most caudal segment of the spinal cord with Normal motor/sensory function on both sides(R/L).

Functional scoring:

10 key muscles

1. C5-elbow flexors
2. C6-wrist extensors
3. C7-elbow extensors
4. C8-finger flexors
5. T1-finger abductors
6. L2-hip flexors
7. L3-knee extensors
8. L4-ankle dorsiflexion
9. L5-long toe extensors
10. S1-ankle plantar flexors

(0-5) score 50+ 50 ==>100

Motor scoring:-

Both right and left sides graded a total of 100 points

For 28 sensory dermatomes, on each side(0-2), a maximum of 112 points-Normal

Management of spinal cord injury:

Management of spinal cord injury begins from ER till post-operative care.

It begins with:

• Immobilization
• IV methylprednisolone (within 8 hours of injury)

Loading dose:

30 mg/kg then

• 5.4 mg/kg over the next  24 hr of starting within 3 hr of spinal cord injury
• 5.4 mg/kg over the next 48 hr if started within 8 hr of injury

Experimental drugs:

1. Naloxones
2. Thyrotropin-releasing hormone
3. GM1 gangliosides
4. Riluzole (Na+ channel blocker) FDA approved for ALS

Criteria for clinical clearances for C-spine

• No posterior or midline tenderness
• Full pain-free active ROM
• No focal neurological deficit
• The normal level of alertness
• No evidence of intoxication
• No distracting injury