Brachial plexus lesions

Esther Vögelin, MD, Prof

SGH Course 12.12.13

Handchirurgie und Chirurgie der peripheren Nerven, Universitätsspital Bern

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C5

C7

C6

C8

TH1

Surgical anatomy of the brachial plexus

• „5-3-6-3-5“ – 5 Roots: C5,C6,C7,C8,TH1 – 3 Trunks: upper, middle, lower – 6 Divisions: 2 upper, 2 middle, 2 lower – 3 Cords: lateral, posterior, medial

– 5 Nerves (musculocutaneus

axillary, radial, median, ulnar) nerves

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Surgical anatomy

C5

C7

C6

C8

TH1

•  Supraclavicular - 3 Trunks

• upper trunk (C5, C6) • middle trunk (C7)

• lower trunk (C8, TH1)

•  Supraclavicular - 5 Roots

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Surgical anatomy • Retroclavicular

– 6 Divisions

– Upper (C5, C6) – Middle (C7) – Lower (C8, TH1)

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Surgical anatomy • Infraclavicular

– 3 Cords • Lateral (C5,C6,C7)

• Posterior (C5,C6,C7,C8,TH1)

• Medial (C8,TH1)

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Surgical anatomy

• Infraclavicular – 5 Nerves • Musculocutaneus nerve(C5,C6,)

• Axillary nerve (C5,C6,)

• Radial nerve (C5,C6,C7,C8,TH1) • Median nerve (C5,C6,C7,C8,TH1) • Ulnar nerve (C7,C8,TH1)

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Nerves and their muscles Plexus Nerves (n) Muscles (m)

Roots C3-C5 Phrenic diaphragma

Roots C5-C7 Root C5

Long thoracic n Dorsal scapular n

Serratus anterior m Levator scapulae m, Rhomboids

Upper trunc C5,C6 Suprascapular n Supra-/infraspinatus m Lateral cord C5,C6,C7

Lateral pectoral n Clavicular portion of pectoral m

Posterior cord C5,C6,C7,C8,TH1

Subscapular n Thoracodorsal n

Teres major m Latissimus dorsi m

Medial cord C7,C8,TH1

Medial pectoral n Medial brachial and antebrachial cutan. n

Sternal portion of pectoral m Pectoral minor m

C5/C6 C5/C6 C5/C6/C7/C8/TH1 C5/C6/C7/C8/TH1 C7/C8/TH1

Musculocutaneous n Axillary n Radial n Median n Ulnar n

Coracobrachial, Biceps, Brachial m Deltoid, Teres minor m Triceps, Brachioradial m, Extensors Pronators, radial wrist-,finger-, thumb flexors Intrinsic hand m, ulnar wrist-,finger flexors

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Examination • Search for associated injury in high energy trauma

– Closed head injury – Chest wall: proximal rib fx,

hematopneumothorax – Spinal cord injury – Vascular injury (6 P‘s: pain, pallor, pulselessness,

poikilothermia{cool skin}, paresthesia, paralysis) – Musculoskeletal injury (shoulder girdle fx,

dissociation, upper limb fx)

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Examination • History

– Severe pain in anesthetic extremityà root avulsion

– Paraesthesia, weakness in other extremities (Para-/Tetraplegia)

– Course: improvement/changes over 3 months

• Traction – Most injuries due to stretch – Point of application, direction of force and

relationship of arm to neck determines nerves involved

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Upper/middle trunk mechanism • Forcible widening of shoulder-neck angle

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Lower trunk mechanism • Separation of scapulohumeral angle

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Examination • Pre- and postganglionic lesion

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Examination • Pre- and postganglionic lesion

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• Extensive longitudinal injury common

– Combination of supra- and infraclavicular injury

• Mixture of avulsion, stretch and rupture

– Variable injury results in eneven recovery of plexal elements

Adult brachial plexus injury

Prof. A. Narakas, 1989

C6 root injury, upper + lower trunk rupture, posterior cord rupture

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Examination • Establish the location of the injury

– Pre-ganglionic (avulsion) vs post-ganglionic (rupture)

– Post-ganglionic levels: root/trunk/division/cord/terminal branches

• Complete vs incomplete lesion • Sensory exam:

– Tinel‘s sign: location and distribution – Sensory loss: dermotomal and peripheral nerve

pattern

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Sensory examination • Tinel‘s sign:

– Present at site of nerve rupture – Advances with nerve regeneration – Absence in neck may imply root avulsion

• Absence of sweating, loss of sympathetic innervation

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Motor examination • Knowledge of pathway from roots to individual muscles, contributions from multiple roots important to localize pathology and plan treatment

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Examination

Pattern Involved roots

Loss of function

Upper trunc plexus palsy: Erb-Duchenne

C5/C6 No shoulder abduction, external rotation, elbow flexion

Upper and middle trunc plexus palsy

C5/C6/C7 + no elbow-, wrist-, finger- extension

Lower trunc plexus palsy: Déjérine-Klumpke

C8/TH1 No intrinsic muscle function, ulnar wrist-, finger flexion

Total plexus paralysis C5/C6/C7/C8/TH1

„flail arm“

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Examination

• Preganglionic lesion – Denervation of rhomboid m, levator scapulae

m, anterior serratus m (Roots C5/C6/C7) – Horner sign (Root C8/TH1) – No tinel sign (no conduction between spinal

cord and ganglion – Asensitive neck (but intact sensible action

potentials) – Hemidiaphragma paralysis (phrenic n) – Pseudomeningomyeloceles: avulsion and

lesion of dura mater and arachnoid – Fractures of transverse process

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Examination • Postganglionic lesion C5/C6*

– Denervation of the following muscles: • Supra-/infraspinate muscles [no abduction (>90°), no external rotation]

• Deltoid m [no flexion, abduction(0-90°), extension] • Pectoralis major: no adduction against resistance • Latissimus dorsi m: asymmetry when coughing, no muscle palpation with both hands against the hips

– No elbow flexion, • Upper trunc (C5/C6) • Lateral cord (C5/C6) • Musculocutaneous nerve, axillary nerve (C5/C6)

* 15% of adult injury Kim DH, Neurosurg focus 16(5), 2004

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Examination • C5, C6, C7 injury

– Absent shoulder abduction, external rotation (no deltoid, no supra/infraspinati)

– No elbow extension (triceps, Brachioradialis m) • Root C7, middle trunc, • Posterior cord (C7) • Radial nerve

– Stretch, rupture or avulsion – Erb‘s palsy + variable triceps, wrist extensor

weakness

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Examination for root avulsion • Motor branches arising from roots

– Dorsal scapular (C5)- Rhomboids: lateral translation and rotation of inferiar angle, subtle

• Motor branches arising from roots – Long thoracic (C5-C7) – Serratus

anterior: winging at medial border

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Examination for root avulsion • Examination of serratus anterior function: shoulder protraction