BRACHIUMBRACHIUM

Fascial SeptaFascial Septa

Divide arm into anterior and posterior Divide arm into anterior and posterior compartments.compartments.

Medial Intermuscular SeptumMedial Intermuscular Septum

From subcutaneous sheath to humerus.From subcutaneous sheath to humerus.Separates muscles of anterior arm from Separates muscles of anterior arm from

medial side of triceps complex.medial side of triceps complex.

Lateral Intermuscular SeptumLateral Intermuscular Septum

From subcutaneous sheath to humerus.From subcutaneous sheath to humerus.Separates muscles of anterior arm from Separates muscles of anterior arm from

lateral side of triceps complex.lateral side of triceps complex.

ANTERIOR BRACHIAL ANTERIOR BRACHIAL COMPARTMENTCOMPARTMENT

Muscles Muscles

Components:Components:Biceps brachiiBiceps brachii

CoracobrachialisCoracobrachialis

Brachialis Brachialis Function:Function:

Forearm flexorsForearm flexors

Biceps also supinates forearmBiceps also supinates forearm

InnervationInnervation

Innervation and functional neurological level:Innervation and functional neurological level:Musculocutaneous nerveMusculocutaneous nerve

C5-6C5-6

Nerves passing through compartment (not Nerves passing through compartment (not innervating anterior compartment structures):innervating anterior compartment structures):

Median nerve.Median nerve.

Ulnar nerve:Ulnar nerve:Through proximal part of anterior compartment.Through proximal part of anterior compartment.

VascularizationVascularization

Brachial arteryBrachial arteryBasilic vein and venae comitantesBasilic vein and venae comitantes

POSTERIOR BRACHIAL POSTERIOR BRACHIAL COMPARTMENTCOMPARTMENT

MusclesMuscles

Components:Components:Triceps brachii.Triceps brachii.

Anconeus.Anconeus.Function:Function:

Forearm extensors.Forearm extensors.

Long head of triceps can extend shoulder Long head of triceps can extend shoulder (brachium).(brachium).

Synergists in forearm supination.Synergists in forearm supination.

Innervation/VascularizationInnervation/Vascularization

Innervation and functional neurological Innervation and functional neurological level:level:

Radial nerveRadial nerve

C7C7Vascular supply to compartment:Vascular supply to compartment:

Deep brachial arteryDeep brachial artery

NERVES and VESSELS IN NERVES and VESSELS IN THE BRACHIUMTHE BRACHIUM

Median NerveMedian Nerve

Supplies flexor muscles on the radial side Supplies flexor muscles on the radial side of the forearm.of the forearm.

Travels with the brachial artery:Travels with the brachial artery:Lateral to artery in upper half of brachium.Lateral to artery in upper half of brachium.

Medial to artery in lower half of brachium.Medial to artery in lower half of brachium.Crosses cubital fossa superficially:Crosses cubital fossa superficially:

With brachial arteryWith brachial artery

Deep to bicipital aponeurosisDeep to bicipital aponeurosis

Ulnar NerveUlnar Nerve

Supplies flexor muscles on the ulnar side Supplies flexor muscles on the ulnar side of the forearm.of the forearm.

Starts in anterior brachial compartment:Starts in anterior brachial compartment:Medial to brachial arteryMedial to brachial artery

Runs with superior ulnar collateral artery.Runs with superior ulnar collateral artery.

Ulnar NerveUlnar Nerve

Pierces medial intermuscular septum:Pierces medial intermuscular septum:Enters posterior compartment of the Enters posterior compartment of the

brachium.brachium.

Passes around (superficial) medial Passes around (superficial) medial epicondyle.epicondyle.

Passes into forearm between two heads of Passes into forearm between two heads of flexor carpi ulnaris muscle.flexor carpi ulnaris muscle.

Radial NerveRadial Nerve

Supplies extensor muscles in posterior Supplies extensor muscles in posterior compartment of brachium as well as compartment of brachium as well as extensor muscles of the wrist and hand.extensor muscles of the wrist and hand.

Also supplies brachioradialis muscle.Also supplies brachioradialis muscle.Descends posterior to the axillary artery:Descends posterior to the axillary artery:

Spirals around the posterior surface of the Spirals around the posterior surface of the humerus in the spiral (radial) groove.humerus in the spiral (radial) groove.

Accompanied by deep brachial artery.Accompanied by deep brachial artery.

Radial NerveRadial Nerve

Pierces lateral intermuscular septum distal Pierces lateral intermuscular septum distal to deltoid insertion.to deltoid insertion.

Passes into forearm:Passes into forearm:Between the brachialis medially and the Between the brachialis medially and the

brachioradialis laterally.brachioradialis laterally.Divides into superficial and deep branches Divides into superficial and deep branches

near lateral epicondyle.near lateral epicondyle.

Radial NerveRadial Nerve

Branches in the axilla and upper third of Branches in the axilla and upper third of the arm:the arm:

Muscular branch to long head of triceps.Muscular branch to long head of triceps.

Muscular branch to medial head of triceps.Muscular branch to medial head of triceps.

Posterior brachial cutaneous nerve.Posterior brachial cutaneous nerve.

Radial NerveRadial Nerve

Branches in the radial groove in middle Branches in the radial groove in middle third of arm:third of arm:

Branch to lateral and medial triceps and Branch to lateral and medial triceps and anconeus.anconeus.

Lower lateral brachial cutaneous nerve.Lower lateral brachial cutaneous nerve.

Posterior cutaneous nerve of the forearm.Posterior cutaneous nerve of the forearm.

Radial NerveRadial Nerve

Branches in the distal third of the arm:Branches in the distal third of the arm:Branch to brachioradialis.Branch to brachioradialis.

Branch to extensor carpi radialis longus Branch to extensor carpi radialis longus (brevis?)(brevis?)

Articular branches to elbow joint.Articular branches to elbow joint.

Musculocutaneous NerveMusculocutaneous Nerve

Pierces coracobrachialis in upper half or Pierces coracobrachialis in upper half or third of brachium.third of brachium.

Innervates muscles of anterior brachial Innervates muscles of anterior brachial compartment.compartment.

Pierces fascia lateral to biceps tendon:Pierces fascia lateral to biceps tendon:Continues as lateral cutaneous nerve of Continues as lateral cutaneous nerve of

the the forearm.forearm.Supplies skin on lateral forearm as far as Supplies skin on lateral forearm as far as wrist.wrist.

Nerves in the BrachiumNerves in the Brachium

Medial brachial cutaneous nerve:Medial brachial cutaneous nerve:Direct branch from medial cord.Direct branch from medial cord.

Medial antebrachial cutaneous nerve:Medial antebrachial cutaneous nerve:Direct branch from medial cord.Direct branch from medial cord.

Cephalic VeinCephalic Vein

Lateral continuation of dorsal venous arch.Lateral continuation of dorsal venous arch.Ascends in superficial fascia along lateral Ascends in superficial fascia along lateral

aspect of forearm and arm.aspect of forearm and arm.Passes through deltopectoral triangle.Passes through deltopectoral triangle.Empties into axillary vein.Empties into axillary vein.

Basilic VeinBasilic Vein

Medial continuation of dorsal venous arch.Medial continuation of dorsal venous arch.Ascends in superficial fascia along lateral Ascends in superficial fascia along lateral

aspect of forearm and arm to middle of aspect of forearm and arm to middle of arm.arm.

Pierces deep fascia and ascends in upper Pierces deep fascia and ascends in upper aspect of arm in deep fascia.aspect of arm in deep fascia.

Joins venae comitantes to form axillary Joins venae comitantes to form axillary vein:vein:

Usually near inferior border of teres major.Usually near inferior border of teres major.

Median CubitalMedian Cubital Vein Vein

Connects cephalic and basilic vein.Connects cephalic and basilic vein.Extends diagonally across bicipital Extends diagonally across bicipital

aponeurosis.aponeurosis.Receives blood from median antebrachial Receives blood from median antebrachial

vein.vein.Drains blood from palmar hand.Drains blood from palmar hand.

Venae ComitantesVenae Comitantes

Veins that parallel arteries:Veins that parallel arteries:Usually two per artery.Usually two per artery.Countercurrent heat exchange.Countercurrent heat exchange.

Brachial ArteryBrachial Artery

Direct continuation of axillary artery.Direct continuation of axillary artery.Begins at inferior border of teres major.Begins at inferior border of teres major.Main branch is deep brachial artery.Main branch is deep brachial artery.Other branches:Other branches:

Superior ulnar collateral:Superior ulnar collateral:To posterior ulnar recurrent.To posterior ulnar recurrent.

Inferior ulnar collateral:Inferior ulnar collateral:To anterior ulnar collateral.To anterior ulnar collateral.

RelationshipsRelationships

Radial nerve to deep brachial artery in Radial nerve to deep brachial artery in radial (spiral groove).radial (spiral groove).

Brachial artery to median nerve.Brachial artery to median nerve.Brachial artery to bicipital aponeurosis.Brachial artery to bicipital aponeurosis.Superior ulnar collateral artery to medial Superior ulnar collateral artery to medial

epicondyle.epicondyle.

RelationshipsRelationships

Inferior ulnar collateral artery to medial Inferior ulnar collateral artery to medial epicondyle.epicondyle.

Radial collateral artery to lateral Radial collateral artery to lateral epicondyle.epicondyle.

Median cubital vein to bicipital Median cubital vein to bicipital aponeurosis.aponeurosis.

RelationshipsRelationships

Ulnar nerve to medial epicondyle.Ulnar nerve to medial epicondyle. Musculocutaneous nerve to coracobrachialis Musculocutaneous nerve to coracobrachialis

muscle.muscle. Musculocutaneous nerve to biceps and Musculocutaneous nerve to biceps and

brachialis muscles.brachialis muscles. Lateral cutaneous nerve of the forearm to the Lateral cutaneous nerve of the forearm to the

bicipital tendon.bicipital tendon.

CUBITAL FOSSACUBITAL FOSSA

Cubital Fossa BoundariesCubital Fossa Boundaries

Lateral:Lateral:Brachioradialis muscleBrachioradialis muscle

Medial:Medial:Pronator teres musclePronator teres muscle

Superior base:Superior base:Line between two humeral epicondylesLine between two humeral epicondyles

Floor:Floor:Supinator and brachialis musclesSupinator and brachialis muscles

Cubital Fossa ContentsCubital Fossa Contents

Lateral to medial:Lateral to medial:Biceps Biceps TTendonendon

Brachial Brachial AArteryrtery

Median Median NNerveerve