Download - Dr. S. Nishan Silva (MBBS). Bones Clavicle Scapula Humerus Shoulder vs Shoulder Girdle.

Dr. S. Nishan Silva(MBBS)

Bones Clavicle Scapula Humerus

Shoulder vs Shoulder Girdle

Joints Sternoclavicular

Joints Sternoclavicular Acromioclavicular

Coracoclavicular ligaments “Suspensory ligaments of the

upper extremity” Two components:

▪ Trapezoid▪ Conoid

Stronger than AC ligaments Provide vertical stability to AC

joint

Joints Sternoclavicular Acromioclavicular Glenohumeral

Most common dislocated joint

Lacks bony stability

Composed of: Fibrous

capsule Ligaments Surrounding

muscles Glenoid

labrum

Ligaments Acromioclavicular

Joint▪ Acromioclavicular

Ligament

Ligaments Glenohumeral

Joint ▪ Glenohumeral

ligaments▪ Superior▪ Middle ▪ Inferior

25% humeral head surface in contact with glenoid

Humeral head coverage increased to 75% with glenoid labrum

Cartilage Glenoid labrum

Shoulder Girdle Muscles Trapezius

Trapezius Origin: superior nuchal line,

external occipital protuberance, ligamentum nuchae and spinous processes of seventh cervical and all thoracic vertebrae

Insertion: lateral third of clavicle, acromion, and spine of scapulartery

Acton: upper fibers elevate scapula, lower fibers depress scapula; if scapula is fixed, one side acting along, draws head toward the same side, and turn face to opposite side; both sides together, draw head directly backward

Latissimus dorsi Origin: spinous

processes of lower six thoracic and all lumbar vertebrae, median sacral crest, and posterior part of iliac crest.

Insertion: floor of intertubercular groove of humerus.

Action: trunk fixed, extends, adducts and medially rotates arm ; arm fixed, elevates trunk.

Shoulder Girdle Muscles Trapezius Serratus Anterior

Winged Scapula

Glenohumeral Muscles Rotator Cuff

▪ Suprispinatus▪ Infraspinatus▪ Teres Minor▪ Subscapularis

Subscapularis Supraspinatus Infraspinatus Teres minor

Supraspinatus, infraspinatus, teres minor, subscapularis

Form cuff around humeral head

Keep humeral head within joint (counteract deltoid)

Abduction, external rotation, internal rotation

Subscapularis is an internal rotator of the arm.

Supraspinatus assists the deltoid in abducting the arm, with its greatest contribution being the initiation of abduction.

Infraspinatus and teres minor muscles both externally rotate the arm.

Teres major Origin: dorsal

surface of inferior angle of scapula

Insertion: crest of lesser tubercle of humerus

Action: medially rotates and adducts arm

Glenohumeral Muscles Latissimus Dorsi Pectoralis Major

Pectoralis major Origin: medial half of

clavicle,sternum,1th-6th costal cartilages.

Insertion: crest of greater tubercle of humerus.

Action: flexes, adducts and rotates arm medially; arm fixed, elevates trunk; elevates ribs 1-6,aidding in forced inspiration.

Glenohumeral Muscles Latissimus Dorsi Pectoralis Major Deltoid

Deltoid Origin: lateral third of

clavicle, acromion, and spine of scapula

Insertion: deltoid tuberosity of humerus

Action: abducts ， flexes and medically rotates, extends, and laterally rotates arm

Glenohumeral Muscles Latissimus Dorsi Pectoralis Major Deltoid Biceps

Arms outstretched with palms up at level of shoulder

Forced supination of hand with elbow flexed at 90 degrees

Glenohumeral Muscles Latissimus Dorsi Pectoralis Major Deltoid Biceps Triceps

Other structures Brachial Plexus Brachial Artery

Formation: Five roots: formed by

anterior rami of C5-C8 and T1 spinal nerves, roots C5 ～C7give rise to long thoracic n.

Three trunks The upper trunk is formed by

the joining of root C4,C5,C6. The middle trunk is the

continuation of root C7. The lower trunk is formed by

the joining of root C8 and T1. Six divisions: above clavicle,

trunks form anterior and posterior divisions

Three cords: below clavicle, divisions form three cords that surround the second portion of axillary a.

Position: passes through the scalene fissure

to posterosuperior of subclavian artery, then enters the axilla to form lateral, medial and posterior cords

Main branches Lateral cord

Musculocutaneous n. Lateral root to median n.

Medial cord Medial root to median n. Ulnar n. Medial brachial cutaneous n. Medial antebrachial cutaneous

n.

Posterior cord radial n. axillary n. thoracodorsal n.

Axillary artery Continuation of subclavian artery

at lateral border of first rib Becomes brachial artery at lower

border of teres major Divided into three parts by

overlying pectoralis minor First portion, above muscle － gives

rise to thoracoacromial a. Second portion, behind muscle －

gives rise to lateral thoracic a. Third portion, below muscle － gives

rise to subscapular a. anterior and posterior humeral circumflex a.; the former then divides into throcodorsal a. and circumflex scapular a.

Axillary a.

Thoracoacromial a.

Musculocutaneous n.

Median n.

Medial antebrachial cutaneous n.

Ulnar n.

Medial brachial cutaneous n.

Intercostobrachial n.Thoracodorsal n. & a.

Long thoracic n. & lateral thoracic a.

Lateral pectoral n.

Name the muscles for Horizontal Adduction

Pect Major (both) Corachobrachialis Deltoid (anterior)

Name the muscles for Horizontal Abduction

Deltoid (post) Infraspinatus Teres minor Lats

List the muscles that do flexion of the shoulder

Coracobrachialis Pectoralis major

(upper to 60°) Anterior Deltoid

• List the muscles that do extension of the shoulder

• Latissimus dorsi• Teres major• Posterior deltoid• Pectoralis major

(lower fibers to neutral)

List the muscles that do adductionadduction of the shoulder

Pectoralis major (lower and upper below 90°)

Coracobrachialis Latissimus dorsi Teres major

List the muscles that do abductionabduction of the shoulder

• Deltoid (all sections)• Supraspinatus• Pectoralis major

(upper past 90°)

List the muscles that do internal rotation of the shoulder

Subscapularis Latissimus dorsi Teres major Anterior deltoid Pect. major

• List the muscles that do external rotation of the shoulder

• Infraspinatus• Teres minor• Posterior deltoid

Name the muscle.

Coracobrachialis

Name the action

Adduction of the shoulder

Also, flexion and hor. add.

Name the muscle.

Subscapularis

Name the action

Internal rotation of the shoulder

Name the muscle.

Deltoid

Name the action

Abduction of shoulder

Name the muscle.

Infraspinatus

Name the action

External rotation

Name the muscle.

Teres Major

Name the action

Adduction of scapula

Name the muscle.

Teres Minor

Name the action if the humerus move directly to the posterior

Extension of the shoulder

Name the muscle.

Supraspinatus

Name the action

Abduction of the shoulder

Coracobrachialis Pect. Major

SubscapularisDeltoid

Supraspinatus Teres Major

InfraspinatusTeres Minor

What position are her shoulders in?

Flexion

What position is his right shoulder in?

Horizontal Abduction andExternal Rotation

What rotation action is his shoulder performing as he continues to through the ball?

Internal Rotation

What position are her shoulders in?

Flexion

What position are his shoulders in?

Horizontal abduction or Extension

1.2.

FlexionExtension

Position of their shoulders?

What is the position of shoulders?

Extension

Pectoralis major Push-ups Pull-ups Bench press Throwing Tennis serve

Latissimus dorsi Chinning Robe climb Dips on parallel bars Pullover exercises Pulldown exercises Rowing

Shoulder action = ?Shoulder muscle(s) = ? Abduction

DeltoidSupraspinatus

Shoulder action = ?Shoulder muscle(s) = ?

Flexion

Ant DeltoidUpper Pect MajorCoracobrach.

Shoulder action = ?Shoulder muscle(s) = ? Horizontal Add.

Ant. DeltoidPect. Major (both)Coracobrachialis

Shoulder action = ?Shoulder muscle(s) = ? Horizontal Abduction

Latissimus DorsiPost. DeltoidTeres MinorInfraspinatus


Adduction

Pect. Major (both)CoracobrachialisLatissimus DorsiTeres Major


Horizontal Add

Ant. DeltoidPect. Major (both)Coracobrachialis


Extension Lats Teres MajorPost. Deltoid Pectoralis Major (lower)Infraspinatus Teres minor


External Rotation

InfrspinatusTeres MinorPost. Deltoid

Side arm dumbbell raisesDeltoidPush-ups Pectoralis majorRowing and pull-oversLatissimus dorsi

Internal RotationExternal Rotation

Internal Rotation

Subscapularis, Ant. Deltoid, Pect, Major, Lats. And Teres Major

External Rotation

External Rotation

Internal Rotation

Abduction (to work the supraspinatus)

Factors Predisposing to Shoulder Pain Instability of glenohumeral joint Weakness in scapular stabilizing muscles Previous injury (dislocation of glenohumeral joint, separation of

AC joint) Hypomobility of cervical or thoracic spine Postural dysfunction Muscle imbalances

Differentiation of Shoulder Pain Active inflammation: pain that occurs or increases at night Irritation of a sensory nerve root: sharp pain, numbing, &

tingling in a dermatome Rotator cuff injury: pain at lateral portion of upper arm,

painful limitation when elevating arm overhead Bicipital tendinitis: well-localized pain at anterior portion of

head of humerus & aggravation with Speed’s test Adhesive capsulitis: stiffness in shoulder, dramatic loss of

arm motion (especially external rotation)

Differentiation of Shoulder Pain Impingement: pain over anterior humerus, loss of internal

rotation, & painful Neer’s test Instability: clunking in shoulder with active circumduction &

excessive joint play in passive motion test for glenohumeral joint

Pain originating in glenohumeral joint: rarely felt at joint, but over lateral brachial region

Characteristics of Shoulder Pain (vs. neck pain) Elicited or increased from active shoulder motion & relieved by

rest Isometric challenge will be painful with localized lesion Painless weakness in arm & shoulder muscles from motor

nerve root problem in cervical spine

Common Dysfunctions and Injuries of the Shoulder Rotator cuff tendinitis (supraspinatus tendinitis) Infraspinatus tendinitis Subscapularis tendinitis Adhesive capsulitis (frozen shoulder) Impingement syndrome Instability syndrome of the glenohumeral joint

Common Dysfunctions and Injuries of the Shoulder Bicipital tendinitis Subacromial (subdeltoid) bursitis Acromioclavicular ligament sprain Suprascapular nerve entrapment Costoclavicular syndrome (part of thoracic outlet syndrome) Pectoralis minor syndrome (part of thoracic outlet syndrome)

Abduction/adduction Painful arc of

abduction – sensitive, not specific

Impringement of inflammed sub-acromial bursae / biceps tendon etc underneath

Name Description Muscles

Scapularretraction [7] (aka scapular adduction)

The scapula is moved posteriorly and medially along the back, moving the arm and shoulder joint posteriorly. Retracting both scapulae gives a sensation of "squeezing the shoulder blades together."

rhomboideus major, minor, and trapezius

Scapularprotraction[7](aka scapular abduction)

The opposite motion of scapular retraction. The scapula is moved anteriorly and laterally along the back, moving the arm and shoulder joint anteriorly. If both scapulae are protracted, the scapulae are separated and the pectoralis major muscles are squeezed together.

serratus anterior (prime mover), pectoralis minor and major

Scapularelevation [8] The scapula is raised in a shrugging motion. levator scapulae, the upper fibers of the trapezius

Scapulardepression [8]

The scapula is lowered from elevation. The scapulae may be depressed so that the angle formed by the neck and shoulders is obtuse, giving the appearance of "slumped" shoulders.

pectoralis minor, lower fibers of the trapezius, subclavius, latissimus dorsi

Arm abduction [9]

Arm abduction occurs when the arms are held at the sides, parallel to the length of the torso, and are then raised in the plane of the torso. This movement may be broken down into two parts: True abduction of the arm, which takes the humerus from parallel to the spine to perpendicular; and upward rotation of the scapula, which raises the humerus above the shoulders until it points straight upwards.

True abduction: supraspinatus (first 15 degrees), deltoid; Upward rotation: trapezius, serratus anterior

Arm adduction[10]

Arm adduction is the opposite motion of arm abduction. It can be broken down into two parts: downward rotation of the scapula and true adduction of the arm.

Downward rotation: pectoralis minor, pectoralis major, subclavius, latissimus dorsi (same as scapular depression, with pec major replacing lower fibers of trapezius); True Adduction: same as downward rotation with addition of teres major and the lowest fibers of the deltoid

Arm flexion [11] The humerus is rotated out of the plane of the torso so that it points forward (anteriorly).

pectoralis major, coracobrachialis, biceps brachii, anterior fibers of deltoid.

Arm extension[11] The humerus is rotated out of the plane of the torso so that it points backwards (posteriorly)

latissimus dorsi and teres major, long head of triceps, posterior fibers of the deltoid

Medial rotation of the arm [12]

Medial rotation of the arm is most easily observed when the elbow is held at a 90-degree angle and the fingers are extended so they are parallel to the ground. Medial rotation occurs when the arm is rotated at the shoulder so that the fingers change from pointing straight forward to pointing across the body.

subscapularis, latissimus dorsi, teres major, pectoralis major, anterior fibers of deltoid

Lateral rotationof the arm[12] The opposite of medial rotation of the arm.infraspinatus and teres minor, posterior fibers of deltoid

Armcircumduction[13]

Movement of the shoulder in a circular motion so that if the elbow and fingers are fully extended the subject draws a circle in the air lateral to the body. In circumduction, the arm is not lifted above parallel to the ground so that "circle" that is drawn is flattened on top.

pectoralis major, subscapularis, coracobrachialis, biceps brachii, supraspinatus, deltoid, latissimus dorsi, teres major and minor, infraspinatus, long head of triceps