Brachial Plexus Injuries & Reconstruction Flashcards
1
Q
Where do the roots, truncks, cords, divisions and terminal branches lie and what are their contributions
A
- 5 Roots - C5-T1 (C8 and T1 exit from above named formina)
- located betwene anterior and middle scalene
- prefixed C4
- post fixed T2
- 3 Truncks - Upper (C5-C6), Middle (C7), Lower (C8-T1)
- located in posterior triangle
- 6 Divisions - Anterior and Posterior division of each
- located posterior to clavicle
- 3 Cords (Lateral, Medial, Posterior) in relation to axillary artery
- located posterior to pectoralis minor
- 5 Terminal branches (Rad, Ax, Uln, Med, MSC)
- located in limb
2
Q
CORDS
what forms and what is formed by each cord
A
- LATERAL CORD
- made up of C5-7 (anterior division of upper and middle trunks)
- forms Lateral pectoral (ant division upper and middle T)
- forms MSC (anterior division of upper and middle T)
- forms lateral contributing branch of median nerve => contributes to sensation
- MEDIAL CORD
- made up of C5-T1 (anterior division of Lower trunk + gets lateral contributing branch to median nerve)
- forms medial pectoral nerve, MABC, MBC
- forms medial contributing branchof median nerve => contributes to intrinsics fx
- POSTERIOR CORD
- made up of C5-T1 (posterior division of all trunks)
- forms upper, lower subscapular n and Td
- forms Radia and Axilary branches
3
Q
What nerves arises proximal to the cords on the brachial plexus?
A
- Dorsal scapular nerve (C5 root)
- Phernic nerve (C3,4,5 roots)
- Long thoracic nerve (C5,6,7 roots)
- Suprascapular nerve (upper trunk = C5,6)???
- Lateral pectoral nerve (upper ttrunk anterior div = C5,6)???
- Subclavius (upper trunk C5,6)
- Paraspinal muscle nerves (longus colli, scalene muscles C5,6,7,8)
- 1st intercostal (T1 root)
4
Q
What is the incidence of OBPP
A
1-2/1000
5
Q
How do you classify BP injuries
A
Pathology
- root avulsion
- nerve rupture
- NIC
Location
- preganglionic (~root avulsion)
- postganglionic( ~nerve rupture)
6
Q
What is important points on Hx and PE for BP injury assessment
A
Hx
- mechanism, arm position when injured
- associated injuries (spine/head/limbs/chest)
- weakness/paresthesia
- improvement with time (delayed assessment)
- LOC/lifethreatening injuries (acute assessment)
PE
- ABC, general exam if acute
- peripheral pulse
- BP exam - according to MRC grading
- root avulsion
- horners (C8,T1 avulsion or traction near)
- head deviated away from injured side (weak paraspinals)
- winging scapula and difficulty raising arm above horixontal ( weak serratus ant)
- winging scapula and cannot be drawn close to vertebral column (weak rhomboids/levator scap)
- subluxed humerus + inability to lift above horizontal (Supraspinatus)
- tally functional and non-functional
- root avulsion
- BP exam sensation
- light touch, 2PD static dynamic, vibration, joint position
- root avulsion
- painful limb
- intact histamine response in anesthestic arm
- intact SSEP in anesthetic arm
7
Q
Spot diagnosis
Spontaneous recovery following diffuse BP injury with weak/slowly recovery arm abduction/external rotation
A
compression of SSN in Scapular Notch
May require release
8
Q
What nerve injury would you suspect with posterior shoulder dislocation
A
axillary nerve rupture
9
Q
Contrast findings for preganglionic vs postganglionic BP injuries
A
- On inspection
- flail arm for both
- head direcetd away from injury in preGG
- winging scapula preGG
- horners preGG
- On palpation and muscle testing
- paralysis of limb for both
- paralysis of diaphragm, serratus, rhomboids preGG
- On palpation and sensory testing
- paresthesia in both
- intact histamine response in preGG
- deafferentiation PAIN in preGG
- Tinels ABSENT preGG
- On investigation
- pseudomeningocele in myelogram preGG
- NCS: absent motor EP for both
- sensory EP in postGG
- ABSENT SENSORY EP in preGG
- EMG: denervation limb for both
- paraspinal denervation preGG
10
Q
What investigations would you order for BP assessment, when and why?
A
- On initial assessment
- Chest X-ray - Fractured cpsine, clavicle, ribs, humerus/shoulder girdle
- Ins/Exp CXR - diaphragm injury (or U/S)
- Arteriogram
- penetrating injury
- normal initial exam then abnormal exam (R/O expanding hematoma)
- 4weeks post trauma
- CT/Myelogram
- to assess root avulsion - traumatic pseudomeningocele correlates w avulsion
- CT/Myelogram
- >3wks post trauma
- ElectoDiagnostic studies:
- EMG
- identify denervation injury
- fibrillation ant rest
- reduced MUP with voluntary effort
- identify denervation injury
- NCS
- identify interruptions in nerve continuity and level of injury
- postive SNAP in paresthetic arm = pathognomoni for root avulsion
*
11
Q
What are treatment options for BP injuries
A
- Non-operative
- PT to maintain ROM/joint mobility
- treat fractures with immobilization
- Operative management
- neurolysis
- autogenous nerve grating
- nerve transfers
- secondary procedures (NT, TT, osteotomies)
12
Q
What are principles for deciding on operative management for BP injuries
A
- Outcomes are better with spontaneous recovery compared to operative Tx
- Patients who require operative Tx have better outcomes if done earlier
- Patients with SUnderland 4-5 injuries benefit from operative intervention, not sunderland 1-2
- Patients w sunderland 3 recvere with some partial deficits with can be corrected w 2’ procedures
13
Q
what are indications for operative intervention for BP injury
A
- Penetrating injury with BP deficits
- clear indication of injury to Roots
- lack of functional recovery after period of observation
14
Q
What are contraindications to primary reconstruction of BP injury
A
ABSOLUTE
- Medically unfit
- demonstrates spontaneous recovery
RELATIVE
- comorbidities, TBI, SCI
- over 1yr since injury in adults
15
Q
How do you prioritize reconstruction of total branchial pleoxpathy
A
Based on principles of
- function significance
- likelihood of regained fx w operation
- degree of difficulty achieving function w 2’ surgery
Order of reconstruction
- Elbow Flexion
- Shoulder stabilization (abdunction,external rotation, flexion)
- Sensation to C5,6 (lateral cord)
- Wrist and finger flexion (with consideration of Triceps extension if planning FFMT for elbow)
- Wrist and finger extension
- Intrinsics
30
Q
What nerve trasnfers are performed for restoration of sensation?
A
Depends on whether partial (1stage) or complete plexopathy (need 2stages)
- Partial plexopathy - use web space donor of non-critical to restore critical.
- eg. upper trunk plexopathy => use ulnar nerve donor 4th Webspace CDN to trasnfer to 1st webspce for median nerve
- Complete plexopathy - 2 stages - restore one nerve proximally an once evidence of reinnervation , use reinnervated nerve non critical sensosry br for critical nerve restoration
- eg. total plexopathy => restor eulnar n with IC trasnfer then once reinnervtion present, do trasnfer listed above (4thWS to 1stWS)
