Download NERVES OF THE FOREARM AND HAND

NERVES OF THE FOREARM AND HAND
LEARNING OBJECTIVES
At the end of the lecture, the student should be able to:
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Describe the innervations to and from the forearm through the brachial plexus.
Give us a brief review of the brachial plexus.
Know divisions of the nerves supplying the forearm.
Know Supra scapular nerves and infra scapular nerves.
Know Nerves of the pectoral region.
Know Nerves of the hand.
INTRODUCTION
 Innervations to and from the upper limb run through the brachial plexus.
 It arises from the c4 through t1.
 It crosses from the base of the neck, axilla before reaching the arm
DEVLOPMENT
 As embryonic so mites migrate to form the limbs, they drag the nerve with
them so that each dermatome and my tome retains the original segmental
innervations
 With so mites migration so of the nerves coming close together and fuse
in a particular fashion, forming a plexus, and in upper limb it is brachial
plexus.
BREIF REVIEW OF THE BRACHIAL PLEXUS
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Formed by the anterior primary ramie of the c4 through t1.
The brachial plexus consists of ,
Roots
Trunks
Divisions
Cords
Nerves
BRANCHES FROM THE ROOTS
 Dorsal scapular nerve innervates the rhomboids and levator scapulae.
 Long thoracic nerve, sarratus anterior.
 Contribution to the phrenic nerve, which supplies the diaphragm.
BRANCHES FROM THE TRUNK
 Suprascapular, supply the supraspinatious and infraspinatious.
 Nerve to salacious, supply the subclavious.
DIVISIONS
 No branches from the divisions of the brachial plexus.
CORDS OF THE BRACHIAL PLESUS
 Lateral cord
 Posterior cord
 Medial cord
LATERAL CORD
 Lateral pectoral nerve
 Lateral root of the median nerve
 Musculocutaneous nerve
POSTERIOR CORD
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Upper suprascapular
Lower suprascapular
Thoracodorsal
Axillary nerve
Radial nerve
MEDIAN NERVE
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Medial cutaneous nerve of the arm
Medial cutaneous nerve of the forearm
Medial pectoral nerve
Medial root of the median nerve
Ulnar
CUTANIOUS NERVES OF THE UPPER LIMB
SEGMENTAL INNERVATION OF THE UPPER LIMB MUSCLES
NERVES SUPPLYING THE UPPER LIMB ARE DIVIDED INTO THE
FOLLOWING GROUPS
 Supra scapular
 Infra scapular
NERVES OF THE SCAPULAR REGION OR SUPRA SCAPULAR NERVES
 Dorsal scapular nerve, arises from the fifth cervical ventral ramus, supply
the levator scapulae and than the rhomboids major and rhomboid minor.
 Long thoracic nerve, formed by the roots ot the fifth to seven cervical
ventral rami, supplies each division of the serratus anterior.
 Nerve to subclavius, arise from the junction of the fifth and the sixth
cervical rami, it passes above the subclavian artery to supply the
subclavius muscle.
 Supra clavicular nerve, branch of the superior trunk supplies the
supraspinitious and infraspinatious muscle.
INFRA SCAPULAR NERVES
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Nerves of the pectoral region
Nerves of the arm
Nerves of the forearm
Nerves of the hand
NERVES OF THE PECTORAL REGION
 Lateral pectoral nerve, larger than the medial and supplies the Pectoralis
major by piercing the pectoral fascia.
 Medial pectoral nerve, supplies the Pectoralis minor and small part of the
Pectoralis major.
 Upper sub scapular supplies the sub scapularis muscle.
 Lower sub scapular, supplies the sub scapularis
 Thoracodorsal accompanies the sub scapular artery and supplies the
latissimus dorsi.
NERVE OF THE ARM
 Axillary nerve, it arises from the posterior cord, it traverses the
quadrangular space, it divides in the space into the anterior and posterior
branches.
 The anterior branch gives supply to the deltoid muscle and the skin orer it.
 The posterior branch gives supply to the teres minor and the lateral
cutaneous nerve of the arm.
 Musculocutaneous nerve, it arises form the lateral cord; it prices the
coracobrachialis and descends laterally between biceps and the brachialis
to the lateral skin of the arm.
 Medial cutaneous nerve of the arm, it is the smallest and most medial
branch of the brachial plexus. Supplies the distal third of the arm on
medial aspect.
 Medial cutaneous nerve of the forearm arises from the medial cord and
supplies the medial aspect of the forearm.
NERVES OF THE FOREARM
 Ulnar nerve, at the elbow the ulnar nerve is at the dorsum of the medial
epicondyle, it enters the forearm between the two heads of the flexor carpi
ulnairis superficial to the posterior and oblique part of the ulnar collateral
ligament.
 It gives Articular branches to the elbow joint.
 Muscular branches of the ulnar nerve, usually two muscular branches,
flexor carpi ulnaris and the medial half of the flexor digitorum profundus.
 Palmer cutanious branch, it arises at the mid of the forearm, it some times
supply the pamaris braves.
 Median nerve enters the forearm between the two heads of the pronator
teres.
 Anterior interosseous nerve, with anterior interosseous artery it descends
anterior to the interosseous membrane.
 Radial nerve, it descends in the arm behind the third part of the axillary
artery and upper part of the brachial artery. it passes through the
triangulate space with the profunda brachii artery.
 On reaching the lateral side of the forearm it pierces the lateral
intermuscular septum the enters the anterior compartment.
 In the triangular space it gives the posterior cutanious nerve of the arm.
 Radial nerve,it desends in the arm behind the third plart of the axillary
artery and upper part of the brachial artery.it passes through the triangulat
space with the profanda brachii artery.
 On reaching the lateral side of the forearm it plerices the lateral
intermuscular septum the enters the anterior compartment.
 In the triangular space it gives the posterior cutanious nerve of the arm.
 It supplies the flesor pollicis longus and lateral part of the flesor digitorium
profondus.
 It supplies all the flesors of the forearm supperfical muscles except the
flesor carlpi ulanris, i-e pronstor teres, flaxor carpi radilais, flesor digitorium
superfacilis, palamaris longus.
RADIAL NERVE
 Radial nerve,it desends in the arm behind the third plart of the axillary
artery and upper part of the brachial artery.it passes through the triangulat
space with the profanda brachii artery.
 On reaching the lateral side of the forearm it plerices the lateral
intermuscular septum the enters the anterior compartment.
 In the triangular space it gives the posterior cutanious nerve of the arm.
 Branches of the radial nerve in the arm
 Muscular branches, triceps,anconeus,brachioradilis,extensor carpi radilis
longus, brachilis.
 Cutaneous branches, posterior cutanious nerve, and lateral cutaneous
nerve of the arm.
 Posterior cutaneous nerve of the forearm.
 Articular branches to the elbow joint.
 Radial nerve supplies the extensor carpai radilis bravis and the supinator
muscle.
 Posterior interosseous nerve, it is the deep terminal branch of the radial
nerve.
 It supplies the suppinator and the extensor carpi radialis brivis it also,
 Extensor digitorium, extensor digiti minimi, extensor carpi ulanris.
 Extensor pollicius longus and extensor indicis
 Abductor pollicus longus and extensor policis brevis.
OF THE HAND
Thenar muscles are supplied by median nerve, abductor pollicius brevis, and
openness pollicis and part of the flexor policis brevis, part of it is supplied by
theulner nerve. The adductor pollicis muscles are supplied by the ulnar nerve.
Hypothanar muscles, abductor gigiti minimi
Opponens digiti minimi
Flexor digit minima all are supplied by the ulnar nerve.
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Dorsal interosseis and palmer interossei are supplied by ulnar nerve.
Numerical muscles are supplied by the ,
Medial two by the ulnar nerve.
Lateral two by the median nerve.