Brachial Plexus Flashcards
List the principles of nerve transfer
- Donor: should be expendable
- Donor: should be close to end-organ target
- Donor: should be synergistic/easy to relearn
- Tension free coaptation – donor distal, recipient proximal
- Motor nerve transfer should be end to end
sensory nerve transfer : end-to-end if critical sensation, end to side if non-critical sensation
What features differentiate a preganglionic from postganglionic BP injury
Preganglionic = root avulsion (proximal to DRG)
Postganglionic = nerve rupture/neuroma in continuity
Evaluation Technique
Supraganglionic Lesion
Infraganglionic Lesion
Inspection
Flail arm, winged scapula, Horner’s syndrome
Flail arm
Manual muscle testing
Paralysis of serratus anterior, rhomboids +/- diaphragm and limb musculature
Paralysis of limb
Head Position
2o denervation of paraspinous muscle
Normal
Sensation
Absent
Absent
Pain
Deafferentation pain
Lower incidence
Horner’s Syndrome
C8 & T1 Avulsion
Traction injury very close to cord
Tinel’s sign
Absent
Present (unless supraganglionic lesions are present at the same level)
Histamine Triple Test
Vasodilation, wheal & flair
Absent
CT/Myelography
Traumatic pseudomeningoceles, obliteration of root detail
Normal
Electromyography
Paravertebral muscle and limb muscle denervation
Limb Muscle denervation
Nerve conduction
Motor conduction absent, sensory present
Motor and Sensory conduction absent
List the nerve transfers to restore Elbow flexion
Donor: UN fascicle of FCU + MN fascicle of FCR/PL/FDS OR Medial Pectoral n, Intercostal, Td, Distal Accessory
Recipient: Biceps brachii, branchialis OR musculocutaneous
List the nerve transfers to restore Elbow Extension
Donor: UN fascicle to FCU, Intercostal
Recipient: Triceps RN
List the nerve transfers to restore Shoulder Abduction and external rotation
Donor: SAN, Pectoral fascicle of C7
Recipient: Suprascapular N
List the nerve transfers to restore Shoulder Abduction
Donor: Intercostals, Medial Pectoral branch, Medial Triceps branch, Td
Recipient: Axillary n
List the nerve transfers to correct scapular winging
Donor: Td, pectoral fascicle of C7
Recipient: LTN
Classify nerve injury
Seddon
Sunderland
Pathology
Structure involved
Recovery pattern
Rate of recovery
Neurapraxia
I
Local conduction block
Gross structures intact
Complete
Fast
Days to weeks
Axonotmesis
II
Axons undergo Wallerian degeneration
Complete
Slow 1mm/day
III
Axon, myelin & endoneurium
Varies depending on endoneurial scarring
Slow 1 mm/day
IV
Axon, myelin, endoneurium & perineurium
Incomplete recovery, neuroma-in-continuity
Nerve Repair or graft
Neurotmesis
V
Transection of nerve
All (inc epineurium)
None
Nerve repair or graft
MacKinnon
VI
Mixed Injury
Components of all the above
How do you classify brachial Plexus injury
By nerve injury type
- Root avulsion
- Nerve rupture
- Neuroma-in-continuity
By location
- preganglioninc
- postganglionic
By anatomical structures involved
- roots, trunk, division, cords, branches
Describe the MRC muscle grading system
Muscle Grading
Observation
0
No contraction
1
Flicker or trace f contraction
2
Active movement, with gravity eliminated
3
Active movement, against gravity
4
Active movement against gravity and resistance
5
Normal power
Describe Erb-Duchenne Palsy
= injury to C5-C6 roots or upper trunk
- Muscles affected: rhomboid, levator scapulae (C5), deltoid, serratus anterior, supraspinatus, infraspinatus, biceps, branchialis, coracobranchialis, brachioradialis, radial wrist extensors, clavicular head of pectoralis
- Functional loss: shoulder abduction, external rotation, elbow flexion, wrist extension
- Sensory loss: lateral arm and thumb/index
Describe Erb’s plus deformity
= injury to C5,6,7
- Muscles affected: as in erb duchenne + triceps, ECRL, ECRB, EDC EPL EPB APL
- Functional loss: as in erb duchenne + loss of elbow, wrist, finger extension
- Sensory loss: thumb, index and long fingers
Describe Klumpke palsy
= injury to C(7),8,T1
- muscles affected: FPL, FDP, FDS, (EDC/EPL), lumbrical, inteross, hypothenar, thenar
- functional loss: finger and thumb flexion, (thumb finger extension)
- sensory loss: anterior and medial arm, ring and little fingers
