Chapter 5
Shoulder Girdle
Darv Nomann R.T. (R)
Les s on 1
Anatomy and Procedures of the Shoulder Girdle
Shoulder Girdle
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Consists of
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Articulates with
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Head of humerus (shoulder joint)
Manubrium of sternum (SC joint)
Each other (AC joint)
Functions to connect the upper limb to the trunk of the body
Articulation of the upper limb with the girdle
Humerus is not considered to be part of the shoulder girdle
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Clavicle
Scapula
Because the upper portion articulates with the shoulder girdle, proximal
humeral anatomy is considered in evaluation of radiographs of the shoulder
joint
Shoulder joint
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Diarthrodial classification by function
Synovial classification by anatomy (structure)
Ball and socket type, capable of all motions
Clavicle
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Classified as a long bone
Lies just above the first rib
Acromial extremity (lateral end) articulates with acromion on
scapula (AC joint)
Sternal extremity (medial end) articulates with manubrium of
sternum (SC joint)
Double curve to body
Curve more pronounced in males than in females
Scapula
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Classified as a flat bone
Forms the posterior portion of the shoulder girdle
Triangular in shape
General Procedural Guidelines
Shoulder, Proximal Humerus, AC joints, Clavicle, and Scapula
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Patient preparation
General patient position
I R s iz e
SID
ID markers
Radiation protection
Patient instructions
Patient Preparation
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Patient preparation for shoulder girdle procedure requires removal
of radiopaque artifacts from the anatomy of interest
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Examples: jewelry, artifacts on clothing (e.g., bra hooks, buttons)
Secure all patient possessions in designated manner and location
General Patient Position
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Shoulder procedures can be performed in erect or recumbent
positions
Consider patient comfort first
IR Size
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Textbook gives most common IR sizes used for shoulder girdle
procedures
Collimated field generally open to size of IR
SID
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SID is standardized as a part of procedural protocol
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When SID is not specified under a projection, Merrill’s Atlas recommends
48˝ (122 cm)
ID Markers
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Consider the use of lead to absorb scatter and how it affects side
marker placement
Radiation Protection
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Shield pediatric patients and patients of reproductive age
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Refer to guidelines on p. 175, Volume 1
Other radiation protection measures
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Close collimation
Optimum technique factors
Patient Instructions
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Explain and demonstrate positions and breathing instructions
Respirations suspended for most exposures
Transthoracic lateral projection may use breathing technique
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Low mA with long exposure time
Radiographic Procedures
Essential Projections: Shoulder
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AP projections
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Internal rotation
External rotation
Neutral position
Transthoracic lateral (Lawrence)
Inferosuperior axial (Lawrence)
PA oblique (scapular Y)
AP oblique (Grashey)
AP Projection in Internal Rotation
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Patient position
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Part position
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Rotate patient slightly toward affected shoulder
Place body of scapula parallel with plane of IR
Important for patients with extreme kyphosis (humpback curvature of the
spine)
Flex elbow slightly
Rotate arm internally and rest back of hand on hip
Place humeral epicondyles perpendicular to IR
Central ray (CR)
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Perpendicular
Enters patient 1˝ inferior to coracoid process
AP Projection in External Rotation
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Patient position
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Part position
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Rotate patient slightly toward affected shoulder
Place body of scapula parallel with plane of IR
Important for patients with extreme kyphosis (humpback curvature of the
spine
Flex elbow slightly
Rotate arm externally and supinate hand
Place humeral epicondyles parallel to IR
CR
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Perpendicular
Enters patient 1˝ inferior to coracoid process
AP Projection in Neutral Position
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For trauma cases
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If possible, have patient rest the palm of the hand against the thigh
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Leave arm in neutral position
Places epicondyles at 45-degree angle to IR
CR directed the same as for other positions
Transthoracic Lateral (Lawrence)
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Note: Projection used for trauma patients who cannot abduct arm
Patient position
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Supine or upright lateral
Affected limb closer to IR
Unaffected limb elevated over head
Transthoracic Lateral (Lawrence)
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Part position
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Do not move injured limb
Insure elevated shoulder is higher than injured shoulder
Center surgical neck of humerus to IR
Transthoracic Lateral (Lawrence)
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CR
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Perpendicular
Enters midcoronal plane at surgical neck
If shoulders are in same plane, CR angled 10 to 15 degrees cephalad
Inferosuperior Axial Projection (Lawrence Method)
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Patient position
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Supine
Head and shoulder elevated on 3˝ radiolucent support
Turn head away from CR
Inferosuperior Axial Projection (Lawrence Method)
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Part position
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Abduct arm to right angle
If possible, place arm in external rotation
Place IR crosswise on table (in a holder) centered to shoulder joint
Inferosuperior Axial Projection (Lawrence Method)
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CR
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Horizontal
Medial angulation of 15 to 30 degrees
Enters axilla; passes through AC joint
Angle depends on abduction of humerus
More abduction = greater angle
PA Oblique (Scapular Y)
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So named because when properly positioned, the acromion and
coracoid process form a Y-shape
Position is particularly useful to diagnose shoulder dislocations
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In the normal shoulder, the humeral head is directly superimposed
over the junction of the Y (acromion and coracoid)
Patient position
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Part position
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Upright, 45 to 60 degrees anterior oblique position
Affected shoulder closer to IR
Arm position is not critical
Maintain patient comfort
CR
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Perpendicular to scapulohumeral joint
AP Oblique (Grashey)
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Patient position
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Part position
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35 to 45 degrees posterior oblique position
Affected shoulder closer to IR
More rotation may be necessary if patient is recumbent
Rotation should place scapula parallel to IR
Head of humerus will be in contact with IR
Abduct arm and slightly internally rotate
Place palm of hand on abdomen
CR
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Perpendicular to glenoid cavity
Enters 2˝ (5 cm) medial and inferior to superolateral border of shoulder
Radiologic Procedures
Essential Projections: AC Joints
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AP projection (Pearson method)
Patient position
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Part position
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Upright required because supine position will reduce dislocation, if present
Arms hanging by side, unsupported
Shoulders in same horizontal plane
Separate exposures made
• One without patient’s arms weighted
• One with weights affixed to patient’s arms
CR
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Perpendicular to midline of body at level of AC joints if bilateral image
Perpendicular to AC joints if separate images required
Radiologic Procedures
Essential Projections: Clavicle
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AP
PA
AP axial
PA axial
Note: PA projections preferred due to reduced OID and improved
image quality. AP projections used on recumbent patients.
AP Clavicle
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Patient position
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Part position
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Upright or supine
Clavicle centered to IR
Arms at sides
Shoulders in same horizontal plane
CR
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Perpendicular to midshaft of clavicle
PA Clavicle
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Patient position
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Part position
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Standing or seated upright facing vertical Bucky
Center clavicle to the midline of the Bucky
Arms relaxed by patient’s side
Shoulders placed in same transverse plane
CR
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Perpendicular
Exits midshaft of the clavicle
AP Axial Clavicle
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Patient position
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Part position
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Upright, lordotic position, if possible
If lordotic position not possible, supine with shoulders in same plane
Center clavicle to center of IR
CR
Lordotic position – 0 to 15 degrees cephalic
Supine position – 15 to 30 degrees cephalic
Amount of angle varies with patient thickness
• Thinner patients = more angle
 Enters midshaft of clavicle
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PA Axial
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Position patient as for PA projection
CR
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15 to 30 degrees caudal to the supraclavicular fossa and the midshaft of
the clavicle
Radiologic Procedures
Essential Projections: Scapula
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AP
Lateral
AP Scapula
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Patient position
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Part position
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Consider patient comfort first
Center affected scapula to grid
Abduct arm to right angle
Flex elbow
CR
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Perpendicular to point 2˝ (5 cm) inferior to coracoid process
Lateral Scapula
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Patient position
45 to 60 degrees anterior oblique position
• Posterior oblique positions can be used, but scapula will be magnified
 Affected scapula in contact and centered to grid
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Part position – to demonstrate acromion and coracoid
Flex elbow and place back of hand on posterior thorax
Adjust to ensure humerus does not overlap scapula
OR
 Bring arm across anterior thorax and grasp opposite shoulder
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Part position – to demonstrate body
Extend arm upward and rest forearm on head
OR
 Bring arm across anterior chest and grasp opposite shoulder
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CR
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Perpendicular to mid medial border of scapula
Les s on 2
Image Critique for Essential Projections of the Shoulder Girdle
Shoulder Projections
AP Projection in External Rotation
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Greater tubercle in profile on lateral side of humerus
Humeral head in profile
Scapulohumeral joint seen with slight overlap of humeral head on
glenoid cavity
Collimated field should include superior scapula, lateral half of
clavicle, and proximal humerus
Outline of lesser tubercle seen between humeral head and greater
tubercle
Soft tissue and bony trabeculae clearly demonstrated
AP Projection/Neutral Position
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Humeral head should be seen in partial profile
Greater tubercle will partially superimpose the humeral head
Some overlap of the humeral head and glenoid should be seen
Collimation should include superior scapula, lateral half of clavicle,
and proximal humerus
Soft tissue and bony details should be visualized
AP Projection in Internal Rotation
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Collimated field includes superior scapula, lateral half of clavicle,
and proximal humerus
Lesser tubercle seen in profile and pointing medially
Outline of greater tubercle superimposing humeral head
Humeral head overlaps glenoid fossa more than in external rotation
and neutral positions
Soft tissue around shoulder and bony trabeculation clearly
demonstrated
Transthoracic Lateral (Lawrence)
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Proximal humerus demonstrated
Scapula, clavicle, and humerus seen through lung field
Scapula superimposed on T-spine
Unaffected clavicle and humerus above shoulder of interest
Inferosuperior Axial Projection(Lawrence)
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Scapulohumeral joint with slight overlap
Coracoid process pointing anteriorly
Lesser tubercle in profile and pointing anteriorly
AC joint, acromion, and acromial end of clavicle projected through
humeral head
Soft tissue and bony detail demonstrated
PA Oblique (Scapular Y)
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Scapular body should not overlap thorax
Acromion seen laterally and free of superimposition
Coracoid process superimposed on or slightly below clavicle
Scapula in lateral profile
Humeral head will be seen
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Superimposed on Y in normal shoulder
Below the coracoid process when shoulder joint is anteriorly dislocated
Below the acromion when shoulder joint is posteriorly dislocated
AP Oblique (Grashey)
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Open joint space between humeral head and glenoid
Glenoid cavity in profile
Soft tissue at scapulohumeral joint
Trabecular detail on glenoid and humeral head
Image Critique Criteria
AC Joints
AP (Pearson)
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AC joints seen with soft tissue and without excessive density
Both AC joints, with and without weights, included on one or two
radiographs
Patient’s body not rotated or leaning
Side markers and weight or nonweight markers
Separation, if present, seen on image with weights
Image Critique Criteria
Clavicle Projections
AP/PA Clavicle
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Entire clavicle centered in collimated field
Uniform density
Lateral half of clavicle above scapula and medial half
superimposing thorax
AP/PA Axial Clavicle
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Most of clavicle projected above ribs and scapula
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Clavicle horizontal
Entire clavicle, AC joints, and SC joints demonstrated
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Medial end overlaps first or second rib
AP Scapula
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Lateral part of scapula free of superimposition of ribs
Scapular horizontal and not obliqued
Scapular detail seen through lung and ribs
Acromion process to inferior angle demonstrated
Lateral Scapula
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Lateral and medial borders superimposed
No superimposition of scapular body on ribs
Humerus does not superimposed area of interest
Acromion to inferior angle demonstrated
Lateral thickness of scapula with proper density