brachialplexus.pptx

The brachial plexus is the network of nerves that sends signals from the spinal cord to the shoulder, arm and hand. A brachial plexus injury occurs when these nerves are stretched, compressed, or in the most serious cases, ripped apart or torn away from the spinal cord.

1. Brachial Plexus

2. Objective Introduction B rachial plexus with all branches Enumerate the root value of all branches of brachial plexus Identify lesions of brachial plexus MCQ

3. INTRODU C TI O N Network of nerves Lies in neck and axilla Formed by ventral rami of C5 to T1 ( roots) Gives rise to nerves - innervate upper limb 3

4. COMPONENT PARTS ROOTS - Five ventral rami (C 5 -T 1 ) TRUNKS – Upper , Middle, and Lower DIVISIONS – Anterior & Posterior from each trunk CORDS – Lateral , Medial and Posterior BRANCHES 4

5. Lo ca tion Roots– Behind scalenus anterior, emerge between scalene muscles Trunks - cross lower part of posterior triangle of neck Divisions - behind clavicle Cords - arranged around 2 nd part of Axillary art in axilla Supraclavicular part - roots and trunks Infraclavicular part – cord and branches

6. C5 C6 C7 C8 T1 UT MT LT Lateral cord 9 Medial cord Posterior cord Formation of Brachial plexus

7. FROM ROOTS Dorsal scapular nerve C5 Long thoracic nerve C5, 6, 7 Unnamed muscular branches from all ant rami C2-C8 scaleni / longus colli C5 root of Phrenic nerve FROM TRUNKS (UPPER) Suprascapular nerve C5 , 6 Nerve to Subclavius C5, 6 No branches arise from Divisions BRANCH E S 14

8. 13 Branches Roots Trunks ( u p p er) Divisions Cords Lateral Medial Posterior 4 2 NIL 3 5 5

9. Lateral cord Lateral pectoral Lateral root of median Musculocutaneous C5, 6, 7 C(5), 6, 7 C5, 6, 7 Medial cord Medial pectoral Medial root of median Medial cutaneous N of forearm Medial cutaneous N of arm Ulnar C8,T1 C8,T1 C8,T1 C8, T1 C(7), 8, T1 Posterior cord Upper subscapular Thoracodorsal Lower suscapular C5, 6 C6, 7,8 C5, 6 BRACHIAL PLEXUS: NERVES FROM CORDS 15

10. 16 DISTRIBUTION OF MAIN NERVES MUSCULOCUTANEOUS Muscles of Anterior Compartment of arm (flexors) MEDIAN Most Flexor muscles of forearm & Intrinsic muscles in hand ULNAR FCU & part of FDP (forearm) and Intrinsic muscles in hand AXILLARY Deltoid & Teres minor RADIAL Innervates all Extensor muscles of arm & forearm

11. DORSAL SCAPULAR NERVE A rise from C 5 roots posterior aspect Run down deep to levator scapulae and two rhomboids. Supply levator scapulae and two rhomboids 17

12. 18 NERVE TO SUBCLAVIUS Smal l & arises nea r the junctio n o f C 5 and C 6 v e n t r al rami ( ERB ' S POINT) Descends anterior to the trunks of plexus and Subclavian vessels connected to Phrenic nerve (if it contains fibres of accessory phrenic nerve.) Supply Subclavius.

13. C6 Suprascapular N 19 N to Subclavius Ant Div Post Div ERB’S POINT

14. 20 LONG THORACIC NERVE Arises from roots C 5,6,7 Forms on first digitations of serratus anterior muscle run vertically downwards just behind the mid axillary line. Nerve supply C5 – supply first two digitations, C6 – next two digitations, C7 – lowest four digitations .

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16. SUPRASCAPULAR NERVE Derived from upper trunk C5,6 at erb’s point Supplies Supraspinatus, Infraspinatus Articular rami to Shoulder and Acromio clavicul ar joint. 23

17. UPPER SUBSCAPULAR NERVE Smaller than lower. Enters Subscapularis at a high level. Frequently double. Supplies subscapularis LOWER SUBSCAPULAR NERVE Pass deep to sub scapular art. Supplies Subscapularis ( lower part ) Teres major 26

18. 27 THORACO - DORSAL NERVE Arises between upper and lower Sub scapular nerves . Accompanies sub scapular artery along posterior axillary wall. Supplies Latissimus dorsi.

19. 28 Lesions in Brachial plexus

20. 29 CAUSES Sudden heavy loads on shoulder Carrying heavy loads on shoulder Symptom and sign Winging of scapula P rominence of medial border of scapula Loss of pushing and punching actions. Abduction of arm affected. Demonstrated by asking the patient to push against resistance with the forearm extended at the elbow and flexed to 90° at the shoulder. Lesion of long thoracic nerve

21. Winging of scapula 30

22. Upper trunk lesions: ERB ’ S PALSY 6 7 5 3 31 4 C 5 1 C 6 2 ERB’S POINT Cause of injury Forceful separation of head from shoulder e.g. during birth fall on shoulder. Nerve roots involved - C5, C6 P osition of limb- Arm hangs by side - Adducted - (no abduction) medially rotated -(no lateral rotation) Extension at elbow.- (no flexion) Forearm is pronated.- (no supination) POLICEMAN ’ S TIP OR WAITER TIP HAND

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25. LOWER TRUNK PALS Y : Klumpke’s palsy Site of Injury Lower trunk (C 8, T1). Medial Cord involved (ulnar, medial cut N of Arm and forearm) Cause of injury Birth injury ( klumpke’s paralysis ) Cervical rib Undue abduction of arm while holding something with hands during fall from height. 34

26. 35 Muscle Involved Ulnar N P aralysis of Intrinsic muscle of hand, ulnar flexors of wrist and fingers Symptom and Sign Claw hand (medial two fingers more affected) due to unopposed action of long flexors fingers and extensors paralysis of all interossei and medial two lumbricals. Sensory loss on ulnar side of hand and forearm .

27. Horner's syndrome – Ptosis ( droping of eyelid) Miosis (shrink pupil) Enophthalmos (sunken eye ball) Anhydrosis (loss of sweat) Loss of ciliospinal reflex -: because of injury to sympathetic fibres that leaves spinal cord through nerve T1

28. Claw hand 36

29. Saturday Night Palsy Injury to radial nerve Mechanism : Crutches pressing in axilla One arm hanging over the arm rest of a chair. Disability -: Loss of elbow extensor Extensor of wrist result in wrist drop Sensory loss:- Small area over back of forearm Dorsal surface of lateral three finger

30. MCQ

31. Q1 Which one is not a branch of lateral cord of brachial Plexus? a. Musculo-cutaneous b. Lateral root of median c. Medial root of median d. Lateral pectoral Medial root of median

32. Q2 Which part of the brachial plexus accompanied around the axillary artery ? a. Cord around Supraclavicular part b. Cord around Infraclavicular part c. Cord with Subscapular art. d. None of the above b. Cord around Infraclavicular part

33. Q3 Root of brachial plexus origin between which muscles? a. Anterior Scalenus and middle scalenus b. Middle scalenus and posterior scalenus c. Between sternocleidomastoid d. All of the above Anterior Scalenus and middle scalenus

34. Q4 A patient, of age 14 year old came with inability to: ( i ) abduct right shoulder, (ii) flex elbow joint and (iii) supinate the forearm after fall down from slope on out-stretched shoulder . What is the site of injury of the nerves and what is the point called? Ans. Site of injury is upper trunk And, point is Erbs point

35. References BD_Chaurasia’s_Human_Anatomy , Volume 1 - Upper Limb Thorax, 6th Edition Vishram Singh