Brachial Plexus Flashcards
Anatomy
C7 travels alone
Roots adjacent to vertebra
Cords in supraclavicular region
Anatomy brachial plexus
Signs of avulsion of nerve root on MR C Spine
- Spinal cord oedema
- Lateral dislocation of spinal cord
- Syringomyely
- Haemorrhage/ spinal cord lesion
- Absence of roots in the spinal canal/ intervertebral foramen
-Post traumatic meningocele
- Oedema/enhancement of paraspinal muscles
Complications of nerve root avulsion
- Spinal cord injury
- Pseudomeningocele
- Post traumatic neuroma
CSF can leak through tear in perineural sheath - may see defect on myelogram
Look for denervation changes in paraspinal musculature
Thoracic outlet syndrome
What are causes?
Signs to look for?
Constellation of sign and symptoms that arise from
compression of the neurovascular bundle by various structures
in the area just above the first rib and behind the clavicle within the
confirmed space of the thoracic outlet.
Look for wasting of thenar and hypothenar eminence.
Causes:
- Cervical rib
- Soft tissue causing compressing
- Posture issues
What are the main appearances of CIDP
- Bilateral symmetric hypertrophy of nerve roots with bulb like enlargement
- Increased T2 signal
- Slight enhancement post GAD
Brachial plexus injury
Thoracic outlet disease
What are types?
When from compression on arteries or veins.
- In this case obtain vascular imaging with arms up and down.
- Look at scalene triangle on sag/axial/coronal view.
When to do imaging for brachial plexus injury?
Not acutely post trauma.
Should wait around 1 month. Will see muscle denervation changes at this point.
Nerve root avulsion is an emergency however - will need surgery.
Schwannoma vs neurofibroma of nerve
What are differences?
No capsule in neurofibroma (schwannoma has)
Neurofibroma will usually have high T2 periphery
Types of nerve injury
How to visualise the cords?
Lateral and posterior to the subclavian artery.
