Complete/Incomplete Spinal Cord injury, Neurological Examination and Asia Chart

Spinal shock can occur and last for about 24-72 hours after spinal cord injury and a/w complete motor and sensory loss, hypotension and bradycardia. (monitor Bp with vasopressor to prevent fluid overload)

Bulbocarvenosus reflex: 
If present, Squeezing of penis/clitoris/pulling of Foley catheter would cause contraction of anal sphincter muscle.

The reflex is spinal mediated and involves S2-S4.

Presence of reflex indicates ends of spinal shock.
(Sometimes absence of reflex could be due to cauda equina syndrome instead of spinal shock)

Sacral Sparing Test was done after ends of spinal shock to determine complete or incomplete spinal injury:
1. flexion of big toe present
2. anal reflex present
3. perianal sensation present (S3-5)

Sacral sparing indicates incomplete spinal cord injury

(pinprick sensation predicts better prognosis of motor function: as lateral spinothalamic is near to lateral corticospinal tract)

spinal cord anatomy:


TYPES OF INJURY:
Central Cord Syndrome


Anterior Cord Syndrome


Brown Sequad


Posterior Cord Syndrome



Determine Level of Spinal Cord Injury/Lesion by using Asia Chart

Difference in level of nerve exit:

Cervical nerve exit above vertebra level, example C4 nerve exit above C4 vertebra and below C3 vertebra

Thoracic nerve exit below vertebra level, example T4 nerve exit below T4 vertebra and above T5 vertebra

Loss of sensation at the dermatomal area and power at myotomal area at C4 spinal cord level would indicates injury at C3 vertebral level. Likewise a radiograph of C3 vertebra injury is expecting sensory and motor impairment to C4 spinal cord level.

In PID (Prolapsed Intervertebral Disc), the location of herniated disc in after level of conus medullaris (L1 vertebra) would determine different type of lesion.

Example, centrally herniated disc would affect nerve of the next vertebral level, lateral herniated disc would affect nerve of the same vertebral level. (Refer diagram below)

ASIA chart impairement score:

Motor power determine grade of impairment:

Summary:

In acute spinal injury (emergency case):
-check patient vitals, bulbocarvenosus reflex to rule out spinal shock, if shock present, manage the shock
-then sacral sparing test to determine complete or incomplete injury
-then neurological examination to determine type and level of injury

1. Neurological Examination (usually exam will specify either upper limb/lower limb):
a. Sensory, dermatome (Light touch, Pin Prick)
b. Motor, (Tone, Power, Reflex)
*always compare both side

2. Determine Type of  Injury:
a. Pure sensory loss
b. Pure motor weakness
c. Combined motor and sensory loss
d. Unilateral/Bilateral

3. Determine Etiology:
Acute: Fracture(burst) 
Gradual: PID, spinal stenosis

4. Confirm diagnosis with special test
eg. Straight leg raising test in PID, perianal sensation to rule out cauda equina syndrome (usually caused by large midline disc herniation or extrusion, emergency and need surgical decompression if patient had urinary retention)