SHOULDER&

ARMKaan Yücel M.D., Ph.D. 12.January.2011 Thursday

Anatomy LabSlides

SCAPULOHUMERAL (INSTRINSIC SHOULDER) MUSCLES

6 scapulohumeral muscles Deltoid, teres major, supraspinatus, infraspinatus, subscapularis, and teres minorpass from scapula to humerus Act on the glenohumeral joint.

All the intrinsic muscles but the deltoid and the subscapularis are muscles of the posterior scapular

region.

Supraspinatus & Infraspinatus

Supraspinatus & Infraspinatus

4 intrinsic shoulder muscles1) Supraspinatus2) Infraspinatus3) Teres minor4) Subscapularis

ROTATOR CUFF MUSCLES

(SITS muscles)

Form a musculotendinous rotator cuff around the glenohumeral joint.

ROTATOR CUFF MUSCLES

Suprascapular nerve

Axillary nerve

Kaan Yücel M.D., Ph.D.

ARM9

An elongated muscle in the superomedial part of the arm.

Coracobrachialis

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Extends from tip of coracoid process of the scapulato medial side of the midshaft of humerus.

Coracobrachialis

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Coracobrachialis

It passes through the axilla and is penetrated and innervated by the musculocutaneous nerve.

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Proximal attachment of this fusiform muscle usually has two heads (bi, two + L. caput, head).short head originates from coracoid process in conjunction with the coracobrachialislong head originates as a tendon from supraglenoid tubercle of scapula.

Biceps brachii

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Two heads a single tendon, inserts onto radial tuberosity.

Biceps brachii

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Triangular membranous band, bicipital aponeurosis, runs from the biceps tendon across the cubital fossa and merges with antebrachial (deep) fascia covering the flexor muscles in the medial side of the forearm.

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Biceps brachii

Originates from the distal half of the anterior aspect of the humerus and from adjacent parts of the intermuscular septa, particularly on the medial side.

It lies beneath the biceps brachii muscle and converges to form a tendon, which attaches to the tuberosity of the ulna & coronoid process of ulna.

Its distal attachment covers the anterior part of the elbow joint.

Brachialis

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Large fusiform muscle in the posterior compartment of the arm. The only muscle of the posterior compartment

Triceps brachii

3 heads originate from: long head infraglenoid tubercle of scapulamedial head & lateral head posterior surface of humerus, superior to radial groove3 heads converge to form a large tendon, inserts on

superior surface of the olecranon of the ulna

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The major artery of the arm

Found in the anterior compartment

Continuation of axillary artery at the lower border of teres major

Terminates distal to the elbow joint, opposite to neck of radius dividing into radial & ulnar arteries.

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Brachial artery

Relatively superficial and palpable throughout its course.

Lies anterior to triceps & brachialis.

As it passes inferolaterally, accompanies the median nerve.

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Brachial artery

Proximal arm lies on the medial side. Distal arm, it moves laterally.

Named BranchesSuperior ulnar collateral arteryInferior ulnar collateral arterycontribute to a network of arteries around the elbow joint. Profunda brachii artery Nutrient arteries to the humerus

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Brachial artery

Deep artery of the arm (L. arteria profunda brachii)

Largest branch & most superior origin

Accompanies radial nerve along the radial groove

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Brachial artery

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4 main nerves pass through the arm:

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Enters the arm from axilla @ inferior margin of teres major muscle.

Passes vertically down the medial side of arm in the anterior compartment

Related to brachial artery throughout its course:

No major branches in the arm, or in the axilla.

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Median nerve

Enters the arm with the median nerve and axillary artery.

Passes distally from the axilla anterior to the insertion of the teres major and to the long head of the triceps, on the medial side of the brachial artery.

In the middle of the arm, penetrates the medial intermuscular septum and enters the posterior compartment.

Passes into the anterior compartment of the forearm. 25

Ulnar nerve

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Radial nerveCutaneous branches Inferior lateral cutaneous nerve of arm skin over lateral & anterior aspects of the lower part of the arm.

Posterior cutaneous nerve of forearmpenetrates through the lateral head of triceps brachii muscle & overlying deep fascia to become subcutaneous.

Anterior to lateral epicondyle, divides into Deep branch Superficial branch

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Radial nerve