Spinal injury and pathology

Question 1

What is an UMN lesion and what symptoms does it result in?

Answer 1

Lesion in brain or spine
Pyramidal weakness (flexors stronger than extensors in arms, extensors stronger than flexors in legs)
Spasticity
Brisk reflexes
Positive babinski’s reflex
Clonus

Question 2

What is a LMN lesion and what symptoms does it result in?

Answer 2

Lesion in nerve root, plexi or peripheral nerve
Flaccid weakness
Normal or reduced tone
Reduced or absent reflexes
Wasting
Fasciculation

Question 3

What are the features of the spinal cord?

Answer 3

Begins at base of skull, right down to conus (L1)
Cervical and lumbar enlargements
Cauda equina

Question 4

What lesions (UMN/LMN) will be in the different levels of the spinal cord?

Answer 4

Lesions in C and T spine > UMN
Lesions in L spine > LMN
Lesions in conus > mixed

Question 5

Where in the body will generally be affected by lesions in the different levels of the spinal cord?

Answer 5

Lesion in C spine > arms and legs
Lesion in T spine > legs
Lesions anywhere > bladder and bowel symptoms

Question 6

What are the spinal cord functions?

Answer 6

Sensory information from body to brain (afferent)
Motor control from brain to body (efferent)
Autonomic function from brain to body
Spinal reflexes

Question 7

Where are the different spinal tract columns in a spinal cross section?

Answer 7

Question 8

What are the two main sensory tracts, what information do they carry and where do they decussate?

Answer 8

DC - proprioception, ascend in dorsal column, crosses over in the medulla
Spinothalamic - decussates immediately and ascend in lateral aspect of spinal cord

Question 9

Where does the motor pathway go?

Answer 9

From motor cortex, through the homunculus, through the internal capsule, through brainstem, crosses over in the pyramids in the medulla, through the ventral horn, ventral root and off to innervate muscles

Question 10

Where do autonomic tracts come from?

Answer 10

Sympathetic preganglionic fibres come from interomediolateral column - T1-L2
Parasympathetic from brainstem and sacrum, and have ganglion near targets

Question 11

What effect will cervical/thoracic spine lesions have?

Answer 11

Pyramidal weakness of arms or legs
Spasticity
Brisk reflexes
Reduced sensation from level
Sphincter involvement

Question 12

What effect will lesions in the lumbar spine have?

Answer 12

Flaccid weakness
Normal/reduced tone
Reduced/absent reflexes
Patchy leg sensory reduction
Sphincter involvement (reduced anal tone)