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Brachial Plexus injuries
(Obstetric)
Dr Kannan K Kumar
Consultant Hand and Brachial Plexus
surgeon
Hosmat hospital
• Dr Paul Brand fellow in Hand surgery and
brachial plexus, Christian medical college,
Vellore
• Kleinert fellow in hand and microsurgery,
University of Louisville, Kentucky, USA
• Fellow in brachial plexus surgery, OGDH,
Yamaguchi, Japan
CONTENTS
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Anatomy
Origin and formation of brachial plexus
Obstetric Brachial Plexus injuries
Treatment
Salvage procedures
ANATOMY
Ventral rami, of the
lower cervical and
upper thoracic nerve
roots
Components of brachial plexus
It includes –
From above the fifth
cervical vertebra to
underneath the first
thoracic vertebra(C5T1).
• The trunks pass laterally
and lies around the
subclavian artery
• Behind the clavicle, each
trunk splits into anterior
and posterior divisions.
FORMATION OF THE BRACHIAL PLEXUS
Cadaver
• FORMATION OF THE BRACHIAL PLEXUS
• Roots
• The ventral rami of spinal nerves C5 to T1 are referred to
as the roots of the plexus.
• Trunks
• Shortly after emerging from the intervertebral foramina ,
these 5 roots unite to form three trunks.
–The ventral rami of C5 & C6 unite to form the Upper
Trunk.
–The ventral ramus of C 7 continues as the Middle Trunk.
–The ventral rami of C 8 & T 1 unite to form the Lower
Trunk.
• Divisions
Each trunk splits into an
anterior division and a
posterior division.
• Cords
• – Upper and Middle
trunks - lateral cord.
• – Lower trunk - medial
cord.
• – Posterior divisions posterior cord.
• – Position relative to the
axillary artery
• III. BRANCHES :
• From the Roots
• Dorsal Scapular nerve
Derived from C5 root
Motor nerve to the
Rhomboideus major and
minor muscles
• Long Thoracic nerve
Derived from C 5,6,7
Innervates the serratus
anterior muscle
FORMATION OF THE BRACHIAL PLEXUS
• From the Upper Trunk
• Nerve to subclavius muscle
• Suprascapular nerve
• From the Lateral Cord
• Lateral Pectoral nerve
Innervates the clavicular
head of the pectoralis major
muscle
• From the Medial Cord
• Medial Pectoral nerve
Innervates the
sternocostal head of the
pectoralis major muscle
Innervates the pectoralis
minor muscle
FORMATION OF THE BRACHIAL PLEXUS
Cutaneous distribution
ANATOMIC VARIATIONS
• The plexus may include ventral rami from C4
or T2 and these are designated as
• Pre fixed- C4 added
• Post fixed- T2 added.
OBSTETRIC BRACHIAL
PLEXUS PALSY
HISTORY
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Early days – congenital deformity.
Smillie [1768] – Obstetric origin
Danyau [1851] – Autopsy – lesion
Duchenne [1861]- traction injury, OBPI
ERB [1875]- pointed lesion at upper trunk
Kennedy [1903]- early surgical repair
Narakas [1981]- microsurgical results.
• Incidence: 0.13 - 4/1000 live births
• Spectrum
• Difficult to diagnose early on –
Pseudoparalysis
Erb’s palsy
• Erb's palsy (Erb-Duchenne Palsy) is a
paralysis of the arm caused by injury to the
upper trunk C5-C6.
• Signs of Erb's Palsy
• Deltoid, biceps, and brachialis muscles.
• The arm hangs by the side and is rotated
medially; the forearm is extended and pronated.
commonly called "waiter's tip hand."
• Erb’s Palsy – Nerves Affected
Left Erb’s point
Klumpke s palsy
• Variant involving the lower roots.
• C8 and T1 nerves.
• Affects, principally, the intrinsic muscles of
the hand and the flexors of the wrist and
fingers.
• The classic presentation of Klumpke's palsy is
the “claw hand” where the forearm is
supinated and the wrist and fingers are
hyperextended with flexion at interphalangeal
and metatarso phalangeal joints.
MECHANISM
• Stretching
• Overweight babies with cephalic
presentations
• Underweight babies with breech
• Forceful widening of angle between the
neck & shoulder.
• Vacuum pump
• Forceps
Associated injuries
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C-spine fracture
Torticollis
Clavicle fracture
Shoulder dislocation
Humerus fracture
Facial nerve palsy
Phrenic nerve palsy
PATHOLOGY
• Lesions range from degree I[neuropraxia]
– V [neurotmesis or root avulsions].
• Upper trunk –1st affected, most vulnerable
part.
• Upper trunk – mostly stretched
• Lower trunks – mostly ruptured
Clinical assessment
• Limb is flail & dangling
• Arm is held in IR, adduction, active abd
not possible, elbow extended, forearm
pronated, thumb flexed.
• Complete paralysis- vasomotor
impairment, pale & marble like color
• Horner’s sign
• Associated # [clavicle,humerus,]
Prognosis
• Complete Recovery (80%)
• Partial recovery
• No improvement.
EMG
• Performed at 3-4 wks- confirm
neuropraxia or axonotmesis (difficult to
perform)
• At 2 months, signs of re-innervation.
• Fluoroscopy- phrenic nerve injury.
• Lumbar puncture- xanthochromic CSF- in
root avulsions.
• C.T myelogram
• Fast spin Echo MRI: preganglionic nerve
root injuries. (only if necessary)
• Large diverticulae and meningoceles are
indicative of root avulsions
DD
• Fracture of clavicle or humerus shaft or
physeal separation
• Septic arthritis / osteomyelitis
• Congenital malformation of plexus
• Postinfectious [varicella] plexopathy of
muscles
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Prognostic signs
Nature of injury
Lower plexus paralysis,
Global involvement,
Persistence of Horner’s and phrenic nerve
palsy
• Presence of Torticollis
Treatment
• Physiotherapy
• ROM ex, facilitation of active movt,
promotion of sensory awareness.
• Avoid abduction & posterior projection of
shoulder. Limb to be supported when
holding baby
• Goals: minimizing bony deformities, Jt
contractues.
• Weight bearing activity-skeletal growth
SURGICAL
Early nerve repair
• Indications:
1. Failure of recovery of biceps or deltoid
at 3 months
2. Group III& IV lesions
3. Presence of Horners sign.
Cookie sign
• Failure to flex the elbow, so as to take the
hand to the mouth.
• 3-6months.
Advantages of nerve repair
• Diminishing potential for axon regeneration
with age
• Cross innervation & muscle imbalance
aborted
• Provide better condition for tendon transfer
• Nerve repair is superior to spontaneous
recovery.
Timing of surgery
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1.
2.
3.
4.
5.
5 months – 1 year
TYPE OF SURGERY
Neurolysis
Direct repair
Nerve grafting
Nerve transfers
Free functioning muscle transfers
Neurolysis
Direct Repair
Direct Repair
Direct Repair
Nerve Grafting
Nerve grafting
Free functioning muscle transfer
Common donors
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Spinal accessory (XIth) nerve.
Intercostal nerves (commonly 3rd to 6th)
Fascicles of the median and ulnar nerves
Opposite C7.
Common recipient nerves
Order of priority of restoration of function
• Elbow flexion(Musculocutaneous nerve)
• Shoulder stability (suprascapular nerve
and axillary nerve)
• Hand prehension
Late OBPP
• Nerve regeneration: some muscles recover
earlier, others paretic  muscle imbalance
• Recovery results from misdirection of
regenerated axons  cross innervation
Cross innervation
• Co-contraction of synergestic & antagonistic
muscles
• Diminishing functional recovery
• Muscle contracture  deformity
HAND DEFORMITY
• In flaccid paralysis of complete lesion
• Difficult to manage & difficult to rehabilitate
• If no active wrist extension & no possible
transfers – W. fusion with comb intermetacarpal arthrodesis.
Take home points
• Obstetric brachial plexus injuries may be
avoidable if timely C-section is performed.
• Early referral to a brachial plexus surgeon once
the diagnosis is made.
• All is not lost – Nerve surgery or other
secondary procedures can improve function
drastically.
Thank you
[email protected]