Unit 3 Shoulder Girdle

Hill-Sachs defect

Anterior dislocation of the humeral head can result in a wedge-shaped compression fracture of the articular surface of the humeral head, called the ________________________________ The fracture is located on the posterolateral humeral head. An exaggerated external rotation of the arm may be required to see the defect. (use Inferosuperior Axial Projection or Lawrence method to see)

neutral rotation of the humerus

Ask the patient to rest the palm of the hand against the thigh. This position of the arm rolls the humerus slightly internal into a neutral position, placing the epicondyles at an angle of about 45 degrees with the plane of the IR. The posterior part of the supraspinatus insertion, which sometimes profiles small calcific deposits not otherwise visualized is seen. AP shoulder. Neutral rotation humerus. Greater tubercle (arrows) Slight overlap of the humeral head on the glenoid cavity

AP Oblique or Grayshey Method

IR- 10 by 12 crosswise CR- 2 inches medial and 2 inches inferior to superolateral border PT position- rotate 35-45 degrees towards affected side, head of humerus in contact with IR, hand over belly, like a bow

Shoulder- AP Oblique Projection or Grayshey Method

IR- 8 by 10 or 10 by 12 in, crosswise to include entire clavicle, lengthwise to include more humerus PT- upright Part Position- Center the IR to the scapulohumeral joint. The joint is 2 inches (5 cm) medial and 2 inches (5 cm) inferior to the superolateral border of the shoulder. • Rotate the body approximately 35 to 45 degrees toward the affected side Adjust the degree of rotation to place the scapula parallel with the plane of the IR. This is accomplished by orienting the plane through the superior angle of the scapula and acromial tip, parallel to the IR.* The head of the humerus is in contact with the IR. CR- Perpendicular to the IR; the central ray should be at a point 2 inches (5 cm) medial and 2 inches (5 cm) inferior to the superolateral border of the shoulder

Inferosuperior Axial Projection or Lawrence method - shoulder

Keep the humerus in external rotation, and adjust the forearm and hand in a comfortable position, grasping a vertical support or extended on sandbags or a firm pillow. Support may be necessary under the forearm and hand. Provide the patient with an extension board for the arm. Lawrence method- Horizontally through the axilla to the region of the AC articulation. The degree of medial angulation of the central ray depends on the degree of abduction of the arm. The degree of medial angulation is often between 15 degrees and 30 degrees. The greater the abduction, the greater the angle. Rafert Mod-Horizontal and angled approximately 15 degrees medially, entering the axilla and passing through the AC joint.

subacromial bursa

One of the largest bursae of the shoulder is the _____________________ _________________. It is located under the acromion and lies between the deltoid muscle and the shoulder joint capsule. The subacromial bursa does not normally communicate with the joint. Other bursae of the shoulder are found superior to the acromion, between the coracoid process and the joint capsule, and between the capsule and the tendon of the subscapular muscle. Bursae become important radiographically when injury or age causes the deposition of calcium.

AP Shoulder

PT-upright, internal or external, possibly neutral CR- 1 in below corocoid process IR- 10 by 12 crosswise Standard views- -AP internal (back of hand against thigh) external (supinated hand) -AP Oblique (Grayshey) -Y-View take note: rotate entire arm! hold breath!

acromioclavicular (AC)

The _____________________ (AC) articulation between the acromion of the scapula and the acromial extremity of the clavicle forms a synovial gliding joint

common positioning landmarks for shoulder radiography.

The acromion, coracoid process, superior angle, and inferior angle are...

supraspinous fossa of scapula

The area above the spine is called the _________________ ____________ and gives origin to the supraspinatus muscle. (scapula)

acromial extremity of clavicle

The clavicle lies in a horizontal oblique plane just above the first rib and forms the anterior part of the shoulder girdle. The lateral aspect is termed the _____________ _______________ and it articulates with the acromion of the scapula.

surgical neck

The constriction of the humerus body just below the tubercles is called the ______________ ________, which is the site of many fractures.

acromion.

The crest of spine arises at the superior third of the medial border from a smooth, triangular area and runs obliquely superior to end in a flattened, ovoid projection called the ...

scapular bone

The flat aspect of the ____________ _______________ lies at about a 45- to 60-degree angle in relation to the anatomic position

sternum

The girdle is completed in front by the ___________, which articulates with the medial end of the clavicle.

External rotation of humerus

The greater tubercle of the humerus and the site of insertion of the supraspinatus tendon are visualized Supinating hand and adjusting epicondyles parallel to the plane of the IR positions the humerus in external rotation AP shoulder. External rotation humerus. Greater tubercle (arrow) Supinating hand and adjusting epicondyles parallel to the plane of the IR positions the humerus in external rotation Humeral head in profile ▪ Greater tubercle in profile on lateral aspect of the humerus

infraspinous fossa of scapula

The infraspinatus muscle arises from the portion below the spine, which is called the ____________________ fossa. The teres minor muscle arises from the superior two thirds of the lateral border of the dorsal surface, and the teres major arises from the distal third and the inferior angle. The dorsal surface of the medial border affords attachment of the levator muscles of the scapulae, greater rhomboid muscle, and lesser rhomboid muscle.

Internal rotation of humerus

The proximal humerus is seen in a true lateral position. When the arm can be abducted enough to clear the lesser tubercle of the head of the scapula, a profile image of the site of insertion of the subscapular tendon is seen Posterior aspect of hand may be placed against hip and epicondyles adjusted perpendicular to the plane of the IR to position the humerus in internal rotation AP shoulder. Internal rotation humerus. Greater tubercle (arrows); lesser tubercle in profile (arrowhead) Lesser tubercle in profile and pointing medially

Humerus

The proximal portion of the _______________ is part of the upper limb and not the shoulder girdle proper.

glenohumeral joint (shoulder) or scapulohumeral articulation

The scapulohumeral articulation between the glenoid cavity and the head of the humerus forms a synovial ball-and-socket joint, allowing movement in all directions This joint is often referred to as the __________________ ___________.

greater tubercle of humerus

The tendon of the subscapular muscle inserts at the lesser tubercle. The _____________ ________________ is located on the lateral surface of the bone, just below the anatomic neck, and is separated from the lesser tubercle by a deep depression called the intertubercular (bicipital) groove.

Y view scapula

Y-View•Acromion (posterior) •Coracoid process (anterior) •Inferior angle•Scapular spine •Body of scapula

The West Point method

________ __________ method is used when chronic instability of the shoulder is suspected and to show bony abnormalities of the anterior inferior glenoid rim. CR- Directed at a dual angle of 25 degrees anteriorly from the horizontal and 25 degrees medially. The central ray enters approximately 5 inches (13 cm) inferior and inches (3.8 cm) medial to the acromial edge and exits the glenoid cavity.

The sternoclavicular (SC)

___________________________________ (SC) articulation is formed by the sternal extremity of the clavicle with two bones: the manubrium and the first rib cartilage . The union of the clavicle with the manubrium of the sternum is the only bony union between the upper limb and trunk. This articulation is a synovial double-gliding joint.

Bursae

are small, synovial fluid-filled sacs that relieve pressure and reduce friction in tissue.

anatomy

because the proximal humerus is included in the shoulder joint, its _____________ is considered with that of the shoulder girdle (Figs. 5-1 and 5-2).

Scapula

classified as a flat bone, forms the posterior part of the shoulder girdle

Clavicle

classified as a long bone, has a body and two articular extremities (see Fig. 5-1).

proximal end of humerus

consists of a head, an anatomic neck, two prominent processes called the greater and lesser tubercles, and the surgical neck

Scapula. A, Costal surface (anterior aspect). B, Dorsal surface (posterior aspect).

costal = anterior, dorsal = posterior

Dislocation

displacement of a bone from its joint space

lateral border of scapula

extends from the glenoid cavity to the inferior angle.

superior border of scapula

extends from the superior angle to the coracoid process

medial border of scapula

extends from the superior to the inferior angles

Scapula Inferior Angle

formed by the junction of the medial and lateral borders and lies over the 7th rib

The scapula superior angle

formed by the junction on the superior and medial borders

The shoulder girdle

is formed by two bones—the clavicle and the scapula.

lesser tubercle of humerus

is situated on the anterior surface of the bone, immediately below the anatomic neck

scapular notch of scapula

its lateral end has a deep depression, the ______________ ______________.

Costal (anterior) surface

of the scapula is slightly concave and contains the subscapular fossa.

clavicle and scapula

shoulder girdle is formed by what 2 bones?

The superior surface of the greater tubercle

slopes posteriorly at an angle of approximately 25 degrees and has three flattened impressions for muscle insertions. The anterior impression is the highest of the three and affords attachment to the tendon of the supraspinatus muscle. The middle impression is the point of insertion of the infraspinatus muscle. The tendon of the upper fibers of the teres minor muscle inserts at the posterior impression (the lower fibers insert into the body of the bone immediately below this point).

A.Proximal Humerus B.Clavicle C.Scapula

the shoulder has 3 parts which are-

scapula lateral angle

thickest part of the body of scapula, ends in a shallow, oval depression called the glenoid cavity

Scapulohumeral joint

tissue-Synovial type-Ball and socket movement-Freely movable

acromioclavicular joint

tissue-synovial type-gliding movement-freely moveable

sternoclavicular joint

tissue-synovial type-double gliding movement-freely moveable

Transthoracic Lateral Projection or Lawrence Method- shoulder

used when trauma exists and the arm cannot be rotated or abducted because of an injury. This method results in a projection 90-degrees from the AP projection and shows the relationship between the proximal humerus and the scapula. IR- 10 by 12 lw Respiration: Full inspiration. Having the lungs full of air improves the contrast and decreases the exposure necessary to penetrate the body. CR- Perpendicular to the IR, entering the midcoronal plane at the level of the surgical neck • If the patient cannot elevate the unaffected shoulder, angle the central ray 10 to 15 degrees cephalad to obtain a comparable radiograph.

The joint space between the humeral head and the glenoid cavity (scapulohumeral or glenohumeral joint) is shown Open joint space between the humeral head and glenoid cavity

what does the Grayshey method show?

Inferosuperior axial shoulder joint: West Point method.

what does this x-ray depict?

Connects the upper limb to the trunk

what is the function of the shoulder girdle?

An inferosuperior axial image shows the proximal humerus, the scapulohumeral joint, the lateral portion of the coracoid process, and the AC articulation.

what structures does the Inferosuperior Axial Projection or Lawrence method of the shoulder show?

The Clavicle

•Classified as a long bone •Lateral aspect is termed the acromial extremity •Medial aspect is termed the sternal extremity •Doubly curved for strength •Curvature is more acute in males than in females

Proximal Humerus

•Greater & Lesser Tubercles •Intertublar groove/bicepital •Head - Articulates w/ scapula •Anatomical neck - Separates head from shaft of humerus •Surgical Neck - Common site of fracture

The Scapula has-

•Three borders •Superior •Medial (vertebral) •Lateral (axillary) •Classified as a flat bone •Forms posterior part of the shoulder •The flat aspect of the one lies at a 45- to 60-degree angle in relation to the anatomic position