Traumatic Brachial Plexus Injury: Assessment and Management Mohamed Khalid MCh.Orth, FRCS.Orth,...
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Transcript of Traumatic Brachial Plexus Injury: Assessment and Management Mohamed Khalid MCh.Orth, FRCS.Orth,...
Traumatic Brachial Plexus Injury:Assessment and Management
Mohamed Khalid MCh.Orth, FRCS.Orth, Diplomate European Board of Hand Surgery
With inputs from Dominic Power, Peripheral Nerve Surgeon, Queen Elizabeth Hospital, Birmingham.
Objectives• Anatomy• Pathomechanics • Pathoanatomy• Pathophysiology• Common clinical patterns• BPI Classification• Key examination points• BPI investigation• Early management• Timing of surgery• Reconstruction priorities• Reconstruction ladder• Evolution of modern techniques• Reconstruction algorithm• Additional procedures• Results• Prognosis in BPI• Research areas• Clinical cases
Brachial Plexus Anatomy
• Anterior primary rami of C5-T1• Phrenic nerve C3/4/5• 3 important nerves originate
above the clavicle– C5 root-dorsal scapular– C5/6/7 roots-long thoracic
nerve (Bell)– C5/6 upper trunk-
suprascapular nerve• T1 contributes preganglionic
sympathetic fibres to stellate ganglion
Pathophysiology• Seddon 1943
– Neuropraxia • Focal demyelination• Axonal continuity
– Axonotomesis• Axonal loss • Wallerian degeneration
– Neurotmesis • Transection of a nerve
• Complex spectrum with several patho-physiological processes co-existing:– Focal ischaemia and oedema– Demyelination– Intraneural bleeding– Axonal loss– Nerve avulsions (post-
ganglionic)– Root avulsions (pre-ganglionic)– Spinal cord oedema and
haemorrhage– Intra- and peri-neural fibrosis– Anterior horn cell death
Common Clinical Patterns• Supraclavicular lesions
– Preganglionic or postganglionic– Myotome / dermatome
distribution• Infraclavicular lesions
– Postganglionic– Proximal peripheral nerve
distribution• Upper, Intermediate, Lower or
TBPI– Upper roots injured most
frequently– 80% patients are likely to have
at least some complete injury
• Upper roots (C5/C6) often postganglionic– Branches and interscalene
ligaments protect roots from avulsion• 60% ruptures• 40% avulsions
• Lower roots (C8/T1) usually preganglionic– Direct line of pull to spinal
cord• 85% avulsions• 15% ruptures
Upper Plexus - C5/6• “Bad shoulder, good hand”• Affects shoulder girdle muscles
– “Waiters tip” – Erb’s palsy – Adducted and internally rotated shoulder
• Root lesion– Serratus anterior, Rhomboids, Suprapsinatus, Infraspinatus,
Deltoid, Biceps brachii, Brachialis, Brachioradialis• More distal lesion
– Rhomboids spared (dorsal scapular nerve)– Serratus anterior spared (long thoracic nerve)
Intermediate Plexus - C7
• Rare in isolation– Tumour– Iatrogenic injury
• Co-exists with upper and lower plexus injuries– C5/6/7– C7/8/T1
• Minor impact– Weakness of wrist extensors– Can be used as ipsilateral intraplexal donor or
contralateral donor for reconstruction
Lower Plexus – C8/T1
• “Good shoulder, bad hand”– Klumpke’s palsy • Weakness FCU, FDP to ulnar digits• Loss of hand intrinsics • Loss of EIP• Loss of EPL• Medial forearm and hand sensory loss• Horner’s syndrome (loss of sympathetic outflow)
Classification of Brachial Plexus Palsy
• Age• Pathological• Anatomical• Combination
• Obstetric• Adult
Classification of Brachial Plexus Palsy
• Age• Pathological• Anatomical• Combination
• Traumatic– Traction, avulsion, penetrating wounds
• Infective– Cervical amyotrophy– Parsonage-Turner (viral brachial neuritis)
• Radiation induced• Malignant
– Pancoast tumour of the lung– Primary nerve tumours
• Iatrogenic– CVLs– Invasive angiography– Neck dissection
Classification of Brachial Plexus Palsy
• Age• Pathological• Anatomical• Combination
• Supraclavicular• Infraclavicular
Classification of Brachial Plexus Palsy
• Age• Pathological• Anatomical• Combination
• Preganglionic• Postganglionic
Classification of Brachial Plexus Palsy
• Age• Pathological• Anatomical• Combination
• Upper plexus– C5/6– C5/6/7
• Lower plexus– C8/T1
• Panplexus– C5-T1
Classification of Brachial Plexus Palsy
• Age• Pathological• Anatomical• Combination
• Leffert– I open– II closed
• IIA Supra-clavicular– Pre-, Post-ganglionic
• IIB Infra-clavicular
– III radiation– IV obstetric
• IVA Erb’s• IVB Klumpke’s• IVC Mixed
Key Examination Points• ATLS
– Serial clinical examination• Flaccid paralysis of involved limb• Associated fractures and dislocations
– First rib, clavicle, cervical transverse processes, ipselateral limb fractures– Shoulder, ACJ , SCJ and scapulo-thoracic dislocations
• De-afferentiation pain• Long tract signs in lower limbs
– Asymmetry of reflexes, clonus, up-going plantar• Horner’s syndrome
– Miosis, ptosis, anhydrosis, enopthalmos• Phrenic nerve palsy• Loss of dorsal scapular nerve• Cervical plexus involvement
– Sensory loss proximal to clavicles– Paralysis of strap muscles– Cervical scoliosis
BPI Investigation– Imaging
• CXR, C spine, shoulder radiographs• MRI• Myelography + CT
– Neurophysiology tests• Somatosensory Evoked Potentials• NCS
– 6/52 neuropraxia resolution– Normal SNCVs and absent MNCVs in preganglionic lesions– Absent SNCVs and MNVCs in postganglionic lesions
• EMG– Fibrillation potentials– Spontaneous muscle depolarisations due to ACh receptor upregulation in
target muscles– Histamine Test
• Is it pre-ganglionic?• Historical interest only
Early Management of BPI• Open injury:
– Early exploration– Debridement– Nerve repair, graft and transfers
• Closed injury:– Physiotherapy
• Shoulder abduction• Shoulder external rotation• Elbow ROM• ROM fingers
– Occupational therapy• Wrist splints• Resting intrinsic plus splints• Skin care for trophic areas• Education
– Regular clinical reassessment• Advancing Tinel test for regeneration in zones of axonotmesis• Deep muscle pain for early sign of reinnervation
Early Management of BPI• Open injury:
– Early exploration– Debridement– Nerve repair, graft and transfers
• Closed injury:– Physiotherapy
• Shoulder abduction• Shoulder external rotation• Elbow ROM• ROM fingers
– Occupational therapy• Wrist splints• Resting intrinsic plus splints• Skin care for trophic areas• Education
– Regular clinical reassessment• Advancing Tinel test for regeneration in zones of axonotmesis• Deep muscle pain for early sign of reinnervation
Early Management of BPI• Open injury:
– Early exploration– Debridement– Nerve repair, graft and transfers
• Closed injury:– Physiotherapy
• Shoulder abduction• Shoulder external rotation• Elbow ROM• ROM fingers
– Occupational therapy• Wrist splints• Resting intrinsic plus splints• Skin care for trophic areas• Education
– Regular clinical reassessment• Advancing Tinel test for regeneration in zones of axonotmesis• Deep muscle pain for early sign of reinnervation
Early Management of BPI• Open injury:
– Early exploration– Debridement– Nerve repair, graft and transfers
• Closed injury:– Physiotherapy
• Shoulder abduction• Shoulder external rotation• Elbow ROM• ROM fingers
– Occupational therapy• Wrist splints• Resting intrinsic plus splints• Skin care for trophic areas• Education
– Regular clinical reassessment• Advancing Tinel test for regeneration in zones of axonotmesis• Deep muscle pain for early sign of reinnervation
Timing of Surgery• Acute closed BPI <6/52
– CT myelography 3-6/52 post injury• Pseudomeningocoeles, myelomalacia and root avulsions
– Unequivocal total BPI (C5-T1 avulsion) • Explore 1-2/12
– All others repeated clinical assessment• Consider EMG and NCS at 6-8/52 • Planned exploration at 3/12 for grafting and nerve transfers
• Delayed presentation <6/12• Consider NCS /EMG / CT myelography• Explore for neurolysis, grafting and nerve transfers
• Delayed presentation >6/12• Consider NCS /EMG / CT myelography• Consider selective distal neurotisations , arthrodeses, tendon transfers and
functioning free muscle transfers
Reconstruction Priorities
• Shoulder and elbow control to enable positioning of a sensate hand for prehension– Shoulder abduction SSN (AxN)– Elbow flexion MCN– Sensate hand (MN / lateral cord)– Finger flexion (MN)– Elbow extension (RN)– Release (RN / PIN)– (Intrinsic function)
Reconstruction Priorities
• Shoulder and elbow control to enable positioning of a sensate hand for prehension– Shoulder abduction SSN (AxN)– Elbow flexion MCN– Sensate hand (MN / lateral cord)– Finger flexion (MN)– Elbow extension (RN)– Release (RN / PIN)– (Intrinsic function)
Reconstruction Ladder in BPI• Neurolysis
• External / internal• Nerve grafts
• Sural, LCNF, MCNF• Plexo-plexal (anatomic)
• Neurotisation • Reinnervation of a denervated motor or sensory end organ• Extraplexal donors for specific functions
• Nerve transfers• Ipselateral C7 or contralateral hemi C7 transfer to median nerve using a
vascularised ulnar nerve graft (in cases of preganglionic C8/T1 lesions) based on superior ulnar collateral vessels
• Arthrodeses• Osteotomies• Tendon transfers• Amputations• Functioning Free Muscle Transfers
Evolution of modern techniques 1• Early exploration <6/52
• Haemorrhage is often problematic• Potential for early recovery of neuropraxic injury• Unreliable intra-operative nerve stimulation
• Poor historical results of late exploration (>6/12) • Distal reinnervation is unsatisfactory
• Long grafts• End plate response diminishes with time
• Move towards earlier exploration in closed injuries (6/52-3/12)– Referrals are often delayed
• Associated injuries (eg IPPV for HI)• BPI is frequently missed • Trauma surgeon education• Supra-regional referrals
Evolution of modern techniques 2• Neurotise rather than plexo-plexal grafting
– “One nerve, one function”– Uncertain condition of root (SSEPs poor predictors)– Co-contraction of reinnervated antagonists
• Importance of reinnervation of the deltoid– Leechavenvongs: Long Head Triceps to anterior axillary nerve
• Distally based transfers more rapid and reliable recovery– Oberlin 1 and Oberlin 2 transfers for elbow flexion– FCR, PL, redundant FDS branches to ECRB, PIN and PT
• Avoid grafts– Longer reinnervation times and less predictable outcomes
• End to side techniques (“Something for nothing”)• FFM transfer when >6/12 since injury
– Muscle reinnervation MRC 3+ not possible after 12/12• Contralateral C7 to provide sensation
– Hemi C7 transfer minimises donor morbidity– Poor motor reinnervation, reasonable sensory to median nerve
• Selective use of osteotomies, arthrodeses, tendon and muscle transfers
Osteotomy
• TBPI• Some C5/6/7 recovery• No wrist extension• Supinated forearm• Poor cosmesis and
function
Osteotomy
• TBPI• Some C5/6/7 recovery• No wrist extension• Supinated forearm• Poor cosmesis and
function
Osteotomy
• Plan– Derotation osteotomy of
forearm– Wrist fusion– Wrist flexor to digital
extensor transfer
Glenohumeral Arthrodesis 1
• TBPI post XI to SSN and ICNs to MCN
• Poor shoulder recovery• GHJ instability with
“pistoning” with elbow flexion
• Shoulder internal rotation with elbow flexion
Tendon and Muscle Transfers
• Trapezius to greater tuberosity• Latissimus dorsi to infraspinatus• Latissimus dorsi to Biceps• Pectoralis major rotationplasty to Biceps• Steindler flexorplasty for assisted elbow flexion• Pedicled Latissimus dorsi to finger flexors
Additional Procedures
• Weak elbow flexion– If co-contraction biceps and triceps consider triceps to
biceps transfer– If weak post Oberlin consider Steindler flexorplasty
• Supination deformity after Biceps reinnervation– Derotation forearm osteotomy
• Weak finger extension– Wrist arthrodesis and wrist flexor to finger extensor
transfers
Prognosis in BPI
• Improved if young (<30 years)• Distal injuries do better (“Time Distance”)• Incomplete motor loss suggests a focal injury – Some neuropraxia likely
• Partial plexus injury better than flaccid paralysis of whole arm
• Pre-ganglionic signs do worse• Associated vascular injuries do worse
Research Areas in BPI• Surgical– Re-plantation of pre-ganglionic avulsions to the CNS
• May reduce brachialgia– (Sciatic conduit to conus medullaris has been used to re-
innervate glutei in paraplegics)• Molecular– Neural transmitters– Nerve growth factors– Neural tubes and neurotropism (Lundborg)
• Rehabilitation– Sensory re-education– Neural plasticity– “Acoustic glove” Lundborg (Sweden)
Case1: Preganglionic C5/C6
• Phrenic to MCN• XI to SSN• Shoulder abduction 70• Biceps MRC 4• Returned to work as a
soldier
Case1: Preganglionic C5/C6
• Phrenic to MCN• XI to SSN• Shoulder abduction 70• Biceps MRC 4• Returned to work as a
soldier• But scapular winging
due to long thoracic palsy
Pediatric Brachial Plexus Palsy• Incidence 0.38 to 1.56 per 1000 LB• Perinatal risk factors:
- Macrosomia- Maternal diabetes- Multiparous pregnancy- Previous deliveries resulting in PBPP- Prolonged labor- Breech delivery- Shoulder dystocia- Assisted and difficult deliveries
Pattern
• Most commonly involves the upper trunk (C5/6)• Rarest is insolated lower trunk• Upper trunk Extra-foraminal most common with
vertex delivery and shoulder dystocia• Right upper limb involved most often because of most
common LOA position in vertex delivery• C5-6 root avulsions most common with Breech
delivery and at times bilateral• Mecahnical cause most common
Diagnosis• Clinical diagnosis most
important• Horner’s syndrome bad
prognostic sign• Serial examinations over
the first few weeks to months
• Observation of spontaneous movements, neonatal reflexes, motor stimulation
Naraka’s Classification
• I Classic Erb’s palsy. 46% cases. Successful spontaneous recovery in 90%
• II Extended upper trunk (C5-7). Waiter’s tip. 29% cases
• III Flail Extremity without Horner’s syndrome• IV Flail Extremity with Horner’s syndrome. May
have associated phrenic nerve palsy and elevated hemi-diaphragm. Limited spontaneous recovery
Prognostic Indicators
• Infants who recover anti-gravity biceps strength by 2-3 months have a complete recovery in 1-2 years
• Infants who do not recover antigravity biceps strength by 5-6 months should undergo micro-surgical reconstruction
• Infants with partial recovery of C5-7 anti-gravity strength will have permanent progressive limitations requiring extensive rehab and salvage surgery