S2_L2: Anatomy, X-ray, CT Scan, & MRI of the Shoulder Flashcards

1
Q

Basic CT Protocol

  1. Taken parallel to the bony glenoid fossa
  2. Taken parallel to the supraspinatus tendon (SST)
  3. For severe or comminuted fractures

A. Axial view
B. Oblique sagittal view
C. Oblique coronal view
D. 3D view

A
  1. B
  2. C
  3. D
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Basic CT Protocol

  1. Reformatted from axial cuts for assessment of complex fractures
  2. Taken perpendicular to the humeral shaft

A. Axial view
B. Oblique sagittal view
C. Oblique coronal view
D. 3D view

A
  1. D
  2. A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Routine Radiologic Evaluation: Basic Projections

  1. AP External or Internal Rotation View
  2. Upright AP view with and without weight
  3. AP or Lateral view

A. For the acromioclavicular joint
B. For the shoulder
C. For the scapula

A
  1. B
  2. A
  3. C
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Enumerate the four shoulder complex structures seen on the x-ray of a newborn

A
  1. Clavicle
  2. Scapular body
  3. Humeral shaft
  4. Proximal humeral head

NOTE: All the structures found in an adult radiograph are not readily seen in a neonatal radiograph. But by ~8 y/o, more of the structures may be viewed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Routine Radiologic Evaluation: AP External Rotation

Modified TF
A. For this view, the image is taken in the true AP anatomic position of the shoulder in ER in the supine position.
B. The central ray is directed perpendicular to a point 1 inch inferior to the coracoid process and the receptor / receiving plate.

A

TT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Routine Radiologic Evaluation: AP Internal Rotation

Modified TF
A. For this view, the image is taken with the arm and shoulder in IR.
B. The central ray is directed perpendicular to a point 1 inch inferior to the coracoid process.

A

TT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Routine Radiologic Evaluation: AP (B) with & without weights / stress

Modified TF
A. This view demonstrates the bilateral AC joints for comparison.
B. The central ray is directed perpendicularly to the midline of the body at the level of the acromioclavicular joints.

A

TT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Routine Radiologic Evaluation: AP (B) with & without weights / stress

Modified TF
A. Stress views (with weights) use 20-25 lbs weight to drag the UE down.
B. In AC joint stability, this view will cause separation of the AC joints.

A

FT

A: Stress views (with weights) use 10-15 lbs weight to drag the UE down.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Routine Radiologic Evaluation: AP View

Modified TF
A. The AP view demonstrates the entire scapula, the medial half of scapula is seen free of superimposition of ribs and lungs; however, the lateral half is superimposed.
B. The central ray is directed perpendicular to the midscapular area at a point 1 inch inferior to the coracoid process.

A

FF

A: The AP view demonstrates the entire scapula, the lateral half of scapula is seen free of superimposition of ribs and lungs; however, the medial half is superimposed.
B: The central ray is directed perpendicular to the midscapular area at a point 2 inches inferior to the coracoid process.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Routine Radiologic Evaluation: Lateral View

Modified TF
A. This view is best for evaluating the body of the scapula as the scapula is projected clear of the rib cage.
B. The central ray is directed perpendicular to the mid-lateral border of the scapula.

A

TT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Routine Radiologic Evaluation: Axillary View of GH joint

Modified TF
A. This view is the anteroposterior axial projection of the GH joint.
B. It demonstrates the glenoid fossa and coracoid process to be able to see if the humeral head is anteriorly or posteriorly displaced.

A

FT

A: This view is the inferosuperior axial projection of the GH joint.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Routine Radiologic Evaluation: Axillary View of GH joint

Modified TF
A. This view can be used to determine the exact relationship of the humeral head to the glenoid fossa in GH dislocations.
B. The central ray is directed horizontally through the axilla toward the acromioclavicular joint with the patient in supine & SH abducted.

A

TT

Additional: The West point view is a variation of this view, with the patient in prone.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Routine Radiologic Evaluation: Anterior Oblique or Scapular Y Lateral

Modified TF
A. For this view, the patient is in a 70-degree posterior oblique position in standing.
B. The central ray is directed through the GH joint, perpendicular to the image receptor.

A

FT

A: For this view, the patient is in a 60-degree anterior oblique position in standing.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Routine Radiologic Evaluation: Anterior Oblique or Scapular Y Lateral

Modified TF
A. This view demonstrates the relationship of the humeral head to the glenoid cavity and also demonstrates the parts of the scapula projected clear of the rib cage.
B. The acromion and coracoid form the upper portion (limbs) of the Y appearance of the scapula, while the
scapular body forms the vertical portion of the Y.

A

TT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Fundamental Tenets of Musculoskeletal MRI

  1. T2 Fat Saturation
  2. Gradient Echo (GRE), Proton Density (PD)

A. Define anatomy
B. Detect abnormal fluid

A
  1. B
  2. A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Various Sequences or Protocols of MRI: Anatomy Sequence

  1. Axial
  2. Oblique sagittal
  3. Oblique coronal

A. T1
B. Proton density

A
  1. B
  2. A
  3. B
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Various Sequences or Protocols of MRI: Fluid-Sensitive Sequence

  1. Axial
  2. Oblique sagittal
  3. Oblique coronal

A. Inversion recovery
B. T2 fat saturated

A
  1. B
  2. A
  3. A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Basic CT Scan vs Basic MRI Protocols for the Shoulder

  1. The most variable protocol
  2. From the top of the AC joint to the proximal humeral diaphysis, and from the scapular body out to the deltoid muscle

A. Basic CT Protocol
B. Basic MRI protocol

A
  1. B (Same area to be scanned as CT scan)
  2. A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Shoulder Region Structures Visualized by Routine Radiologic Evaluation

  1. Entire clavicle bilaterally
  2. AC Joint
  3. Upper lateral portion of scapula
  4. GH joint bilaterally as seen on AP view

A. AP external rotation
B. AP internal rotation
C. AP bilateral with & without weights / stress view
D. A and B only

A
  1. C
  2. D
  3. D
  4. C
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Shoulder Region Structures Visualized by Routine Radiologic Evaluation

  1. Proximal 1/3 of humerus
  2. Sternoclavicular joint bilaterally
  3. Lateral 2/3 of clavicle

A. AP external rotation
B. AP internal rotation
C. AP bilateral with & without weights / stress view
D. A and B only

A
  1. D
  2. C
  3. D
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

The following are indications of CT scan for the shoulder, EXCEPT:

A. Severe trauma
B. Assessment of alignment and displacement of fracture fragments
C. Identification of loose bodies in the glenohumeral joint
D. Implanted cochlear hearing aids
E. None

A

D. Implanted cochlear hearing aids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Case: L.M. c/o pain when doing overhead activities. MD suspects labral or rotator cuff pathology & wants L.M. to undergo imaging evaluation. It was also noted on L.M.’s patient chart that they had a corrective scoliosis surgery in the past, where 12 screws were placed onto their spine (T8-L1). What imaging evaluation is best to use for L.M.’s case?

A

CT Scan

It is indicated for evaluation of labral or rotator cuff pathology, if MRI is unavailable or contraindicated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

The following are indications of MRI for the shoulder, EXCEPT:

A. Rotator cuff tendon abnormalities, RC tears
B. Cysts, Superior Labrum Anterior-Posterior (SLAP) Lesions
C. For classification and staging of shoulder conditions
D. GH chondral abnormalities, osteochondral fractures, cartilage degeneration
E. None

A

E. None

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

The following are indications of MRI for the shoulder, EXCEPT:

A. Muscle atrophy, degeneration
B. Conditions affecting the Supraspinatus Outlet (Os acromiale, spurs)
C. Disorder of the long head of the biceps brachii (Tears, tendinopathy, subluxation, or dislocation)
D. Vascular Conditions (Aneurysms, stenosis)
E. None

A

E. None

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Advanced Imaging Evaluation of the Shoulder

  1. Assess for occult fractures
  2. On axial view, assess the relationship of humeral head to glenoid fossa
  3. Check for bony injury from dislocation or trauma

A. Alignment of anatomy on CT Scan
B. Alignment of anatomy on MRI

A
  1. B
  2. A (For MRI, the humeral head should also sit in the middle of the glenoid fossa)
  3. B
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Advanced Imaging Evaluation of the Shoulder

  1. Check for bony disruptions at tendon attachments
  2. On sagittal oblique view, check configuration of the acromion process

A. Alignment of anatomy on CT Scan
B. Alignment of anatomy on MRI

A
  1. B
  2. A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Advanced Imaging Evaluation of the Shoulder

  1. Assess for bone bruises or marrow edema seen as any hyperintense area in T2 weighted image
  2. Assess for any destruction, disease, or infection
  3. Assess for stress fractures

A. Bone Signal on MRI
B. Bone Density on CT Scan

A
  1. A
  2. B
  3. A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Advanced Imaging Evaluation of the Shoulder

  1. Assess for cysts, cortical hypertrophy and sclerosis (humeral head)
  2. Assess for osteochondral injuries
  3. Assess integrity of cortical (most dense) and cancellous (less dense) bone

A. Bone Signal on MRI
B. Bone Density on CT Scan

A
  1. B
  2. A
  3. B
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Advanced Imaging Evaluation of the Shoulder

  1. Check for free fracture fragments
  2. Check for encroachment in subacromial space on oblique sagittal view
  3. Check for irregularities on AC joint surface

A. Edema on MRI
B. Cartilage/ Joint Spaces on CT Scan

A
  1. B
  2. B
  3. B

NOTE: Acromions that can cause impingement (hook type) can lead to encroachment in the subacromial space.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Advanced Imaging Evaluation of the Shoulder

  1. Assess smooth chondral surface of GH joint space on axial and sagittal cuts
  2. Check for edema under coracoacromial arch in impingement syndrome

A. Edema on MRI
B. Cartilage/ Joint Spaces on CT Scan

A
  1. B
  2. A

NOTE: In osteoarthritis, there is no smooth subchondral/chondral surface.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Advanced Imaging Evaluation of the Shoulder

  1. Check biceps tendon long head at bicipital groove
  2. Assess subacromial or subdeltoid bursa, it must have minimal or no fluid
  3. Synovial cysts from rheumatoid arthritis, large cuff tears

A. Soft tissue and synovial tissue on MRI
B. Soft tissues on CT Scan

A
  1. A
  2. A
  3. A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Advanced Imaging Evaluation of the Shoulder

  1. Assess continuity of RC muscles, increase in signal is due to inflammation at the tear site
  2. Check insertion of RC to bone for avulsion injuries, especially supraspinatus tendon

A. Soft tissue and synovial tissue on MRI
B. Soft tissues on CT Scan

A
  1. A
  2. B
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Configuration of the Acromion (Seen on Sagittal View of CT Scan)

  1. Curved downward into the rotator cuff outlet
  2. Flat
  3. Hooked downward into the rotator cuff outlet
  4. Seen in rotator cuff tears or impingement

A. Type 1
B. Type 2
C. Type 3

A
  1. B
  2. A
  3. C
  4. C
34
Q

MRI: Structures Seen Best

  1. Acromion
  2. Glenohumeral joint
  3. Acromioclavicular joint
  4. Glenohumeral Ligaments

A. Oblique sagittal plane
B. Oblique coronal plane
C. Axial plane
D. Both A and B
E. Both A and C
F. Both B and C

A
  1. A
  2. F
  3. B
  4. E (May need to do an arthrogram)
35
Q

MRI: Structures Seen Best

  1. Subscapularis muscle and tendon, seen longitudinally
  2. Teres minor, muscle and tendon, seen longitudinally
  3. Supraspinatus muscle and tendon, in cross section
  4. Subacromial/subdeltoid bursa

A. Oblique sagittal plane
B. Oblique coronal plane
C. Axial plane
D. Both A and B
E. Both A and C
F. Both B and C

A
  1. C
  2. C
  3. A (in supraspinous fossa)
  4. B
36
Q

MRI: Structures Seen Best

  1. Infraspinatus muscle and tendon, seen longitudinally
  2. Labrum, superior and inferior portions
  3. Labrum, anterior and posterior portions

A. Oblique sagittal plane
B. Oblique coronal plane
C. Axial plane
D. Both A and B
E. Both A and C
F. Both B and C

A
  1. B (Seen in a more posterior cut)
  2. B
  3. C
37
Q

MRI: Structures Seen Best

  1. Biceps tendon, long head seen in cross section
  2. Supraspinatus muscle and tendon, seen longitudinally
  3. Coracoacromial Arch

A. Oblique sagittal plane
B. Oblique coronal plane
C. Axial plane
D. Both A and B
E. Both A and C
F. Both B and C

A
  1. C
  2. B
  3. A
38
Q

MRI: Structures Seen Best

  1. Infraspinatus muscle and tendon, in cross section
  2. Coracoacromial Ligament

A. Oblique sagittal plane
B. Oblique coronal plane
C. Axial plane
D. Both A and B
E. Both A and C
F. Both B and C

A
  1. A
  2. A
39
Q

TRUE OR FALSE: The subscapularis inserts in the greater tuberosity.

A

False, the subscapularis inserts in the lesser tuberosity.

40
Q

A 45 yo male sustained a shoulder injury while riding a motorcycle. He claims his right shoulder hit the ground hard and heard a snap and severe pain immediately followed. He was rushed to the hospital where an X-ray was done. You noted a widened AC joint and a fracture of the middle third of the clavicle. What is the normal measurement of the AC joint space?
A. 0.3-0.8 cm
B. 0.8-1.0 cm
C. 1.0-1.3 cm
D. 3.0-8.0 cm

A

A. 0.3-0.8 cm

41
Q

TRUE OR FALSE: The oblique sagittal plane cuts in CT scan of the shoulder is referenced parallel to the bony glenoid fossa.

A

True

42
Q

If your patient was contraindicated to have an MRI, what is an alternative imaging modality to use to view soft tissue?
A. CT Scan
B. Arthrography
C. SPECT
D. X-ray of the shoulder

A

B. Arthrography

43
Q

What is the normal coracoclavicular distance (between the inferior aspect of the clavicle and the coracoid process)?
A. 0.3-0.8 cm
B. 0.8-1.0 cm
C. 1.0-1.3 cm
D. 3.0-8.0 cm

A

C. 1.0-1.3 cm

44
Q

TRUE OR FALSE: The critical zone is defined as a hypovascular region of the supraspinatus tendon located 1cm proximal to the greater tuberosity.

A

True

45
Q

TRUE OR FALSE: The acromion of a newborn baby is visible on routine radiographs of the shoulder.

A

True

46
Q

TRUE OR FALSE: Contrast media injected into the shoulder normally leaks into the biceps tendon bursa.

A

True

47
Q

TRUE OR FALSE: The central ray of the X-ray beam is directed over the coracoid process during an AP External Rotation view of the shoulder.

A

False

48
Q

AC ligamentous injury grading

Widening of the acromioclavicular joint space 1.5 cm or greater with a 50% or more increase in the coracoclavicular distance.

A. Grade I: Mild sprain
B. Grade II: Moderate sprain
C. Grade III: Severe sprain

A

C. Grade III: Severe sprain

49
Q

AC ligamentous injury grading

Widening of the AC joint space to 1.0 to 1.5 cm with a 25% to 50% increase in the coracoclavicular distance.

A. Grade I: Mild sprain
B. Grade II: Moderate sprain
C. Grade III: Severe sprain

A

B. Grade II: Moderate sprain

50
Q

AC ligamentous injury grading

Minimal widening of the acromioclavicular joint space with the coracoclavicular distance still within normal range.

A. Grade I: Mild sprain
B. Grade II: Moderate sprain
C. Grade III: Severe sprain

A

A. Grade I: Mild sprain

51
Q

AC ligamentous injury grading

AC & CC ligaments are sprained (over-stretched but still intact).

A. Grade I: Mild sprain
B. Grade II: Moderate sprain
C. Grade III: Severe sprain

A

A. Grade I: Mild sprain

52
Q

AC ligamentous injury grading

AC ligaments are torn, coracoclavicular ligaments are sprained.

A. Grade I: Mild sprain
B. Grade II: Moderate sprain
C. Grade III: Severe sprain

A

B. Grade II: Moderate sprain

53
Q

AC ligamentous injury grading

Both the AC and coracoclavicular ligaments are torn. The AC joint is dislocated and the clavicle appears to be displaced superiorly (total disruption).

A. Grade I: Mild sprain
B. Grade II: Moderate sprain
C. Grade III: Severe sprain

A

C. Grade III: Severe sprain

54
Q

The following are indications for x-ray of the shoulder, EXCEPT:

A. Trauma, including suspected physical abuse
B. Systemic disease or nutritional deficiencies
C. Primary non neoplastic bone pathologies
D. Evaluation of soft tissue for suspected foreign bodies
E. None

A

E. None

55
Q

The following are indications for x-ray of the shoulder, EXCEPT:

A. Pre-operative, post-operative, and follow-up studies
B. Pain
C. Correlation of abnormal skeletal findings on other imaging studies
D. Osseous changes secondary to metabolic disease, osteoporosis
E. None

A

E. None

56
Q

The following are indications for x-ray of the shoulder, EXCEPT:

A. Neoplasms and infections (late stages of infection)
B. Arthropathies
C. Vascular lesions
D. Congenital syndromes and developmental disorders
E. None

A

E. None

57
Q

The shoulder complex is dynamically stabilized by ____ muscles.

A

rotator cuff (SITS)

58
Q

TRUE OR FALSE: The shoulder complex is made up of the proximal humerus, scapula, and clavicle.

A

True

59
Q

Ligaments of the shoulder complex

  1. Coracohumeral ligament
  2. Superior, middle, & inferior glenohumeral ligaments

A. Anterior reinforcement
B. Superior reinforcement
C. Posterior reinforcement
D. Inferior reinforcement

A
  1. B
  2. A

NOTE: The coracohumeral ligament splits into two to allow the biceps muscle to pass.

60
Q

Ligament that is the primary stabilizer of the AC joint

A

Coraco-clavicular ligaments
* Lateral - Trapezoid
* Medial - Conoid

61
Q

The 2 ligaments that are the AC joint capsule reinforcements

A

Superior and inferior acromioclavicular ligaments

62
Q

Which aspect of the GH joint is the weakest because there is no reinforcement by ligaments or muscles in this area?
A. Superior
B. Inferior
C. Anterior
D. Posterior
E. Medial
F. Lateral

A

B. Inferior

63
Q

Modified TF
A. CT scan is used for evaluation of any condition typically seen by MRI if MRI is contraindicated.
B. The use of an intra-articular contrast for a CT arthrogram (dye injected on capsule) is performed if MR arthrogram is contraindicated.

A

TT

64
Q

Radiologic Observations: Routine Radiologic Evaluation

The profile of the scapular body is clearly seen. Fractures of the scapular body are readily visible on this view.

A. AP external rotation
B. AP internal rotation
C. AP bilateral with & without weights / stress view
D. AP view
E. Lateral view

A

E. Lateral view

65
Q

Radiologic Observations: Routine Radiologic Evaluation

All three borders and angles of the scapula are usually visible.

A. AP external rotation
B. AP internal rotation
C. AP bilateral with & without weights / stress view
D. AP view
E. Lateral view

A

D. AP view

66
Q

Radiologic Observations: Routine Radiologic Evaluation

The AC joint is evaluated by examining the relationship of the acromion to the clavicle. Additionally, the relationship of the coracoid process to the clavicle is also examined.

A. AP external rotation
B. AP internal rotation
C. AP bilateral with & without weights / stress view
D. AP view
E. Lateral view

A

C. AP bilateral with & without weights / stress view

67
Q

Radiologic Observations: Routine Radiologic Evaluation

The greater tuberosity is visualized in profile at the most lateral aspect of the humeral head. The lesser tuberosity is superimposed at the mid-area of the humeral head.

A. AP external rotation
B. AP internal rotation
C. AP bilateral with & without weights / stress view
D. AP view
E. Lateral view

A

A. AP external rotation

68
Q

Radiologic Observations: Routine Radiologic Evaluation

The patient’s arm is abducted and externally rotated. This position allows the scapula to abduct and rotate upward so that the lateral half is now cleared of the rib cage and can be evaluated in more detail.

A. AP external rotation
B. AP internal rotation
C. AP bilateral with & without weights / stress view
D. AP view
E. Lateral view

A

D. AP view

NOTE: In conditions such as adhesive capsulitis, patients are unable to abduct and externally rotate the shoulder fully. Thus, only the highest permissible ROM is sufficient for viewing the scapula.

69
Q

Radiologic Observations: Routine Radiologic Evaluation

The patient’s arm is positioned across the front of their chest to free the body of the scapula from superimposition of the humeral shaft, or the patient’s arm may be positioned behind their back to free the acromion and coracoid process form superimposition of the humeral head.

A. AP external rotation
B. AP internal rotation
C. AP bilateral with & without weights / stress view
D. AP view
E. Lateral view

A

E. Lateral view

70
Q

Radiologic Observations: Routine Radiologic Evaluation

The greater tuberosity is superimposed over the mid-area of the humeral head. The lesser tuberosity is now seen in profile on the medial aspect of the humeral head.

A. AP external rotation
B. AP internal rotation
C. AP bilateral with & without weights / stress view
D. AP view
E. Lateral view

A

B. AP internal rotation

71
Q

Radiologic Observations: Routine Radiologic Evaluation

  1. Any calcium deposits present in muscles, tendons, or bursae of the shoulder may also be demonstrated.
  2. The vertebral and lateral borders of the scapula are superimposed behind the rib cage.
  3. The coracoid process is visualized end-on

A. AP external rotation
B. AP internal rotation
C. A and B
D. None

A
  1. C (Calcific tendinitis of the rotator cuff, especially supraspinatus, is seen above the spine of the scapula)
  2. C
  3. C
72
Q

Radiologic Observations: Routine Radiologic Evaluation

  1. The crest of the spine of the scapula can be seen extending across the scapula and broadening into the acromion.
  2. The acromioclavicular joint is seen superior to the glenohumeral joint.
  3. The medial portion of the humeral head is partially superimposed on the glenoid fossa. Thus, the glenohumeral joint space is not visualized as a completely “open” joint space.

A. AP external rotation
B. AP internal rotation
C. A and B
D. None

A
  1. C
  2. C
  3. C
73
Q

Radiologic Observations: Routine Radiologic Evaluation

In the AP external rotation view, the average width of the glenohumeral joint can be observed by drawing lines across the joint surfaces. This distance is an average of ___ mm.

A

5 mm

NOTE:
Distances greater than this can be suggestive of joint effusion, acromegaly or posterior humeral dislocation.
Distances narrower than this can suggest degenerative joint disease or rheumatoid arthritis.

74
Q

Modified TF
A. MR Arthrography combines the techniques of arthrography with MR imaging to benefit from the added information afforded by intra-articular distention, done by injecting a dye into the shoulder capsule.
B. The distention (expansion) allows evaluation of structures that are often too crowded, such as the labrum, glenohumeral ligament, biceps anchor, and partial articular sided tears of the supraspinatus tendon.

A

TT

NOTE: The labrum is normally hypodense (dark)

75
Q

Advanced Imaging Evaluation

  1. To assess continuity and diagnosing tears
  2. To assess cross-sectional areas and reveal any atrophy (fatty degeneration → infiltration)

A. Perpendicular view
B. Parallel view

A
  1. B
  2. A (Best seen in oblique sagittal cuts)
76
Q

CT Scan Structures Seen

  1. Labrum (superior and inferior portions)
  2. Glenohumeral articulation
  3. Articular cartilage integrity at humeral head
  4. Glenoid rim (superior and inferior)

A. Axial plane
B. Coronal plane
C. Three-dimensional reconstruction

A
  1. B
  2. A
  3. A
  4. B
77
Q

CT Scan

  1. Any bony resorption at the greater tuberosity from the absence of normal rotator cuff tension if torn
  2. Glenohumeral joint surfaces

A. Axial plane
B. Coronal plane
C. Three-dimensional reconstruction

A
  1. A
  2. B (Note: You will see the anterior and posterior portions of the rim best on the axial view)
78
Q

CT Scan Structures Seen

  1. Greater tuberosity
  2. Subacromial joint space, check for any bony abnormalities or bony fragments
  3. Any bony irregularities at greater tuberosity due to avulsion fractures
  4. Configuration of acromion

A. Axial plane
B. Coronal plane
C. Three-dimensional reconstruction

A
  1. B
  2. B
  3. A
  4. B
79
Q

CT Scan

  1. Any Bankart fractures/lesions at the glenoid rim
  2. Used to define complex fractures and help with surgical planning accurately
  3. Has the ability to subtract other structures to isolate the bone in question

A. Axial plane
B. Coronal plane
C. Three-dimensional reconstruction

A
  1. A
  2. C
  3. C
80
Q

CT Scan: Axial Plane

  1. Fracture of anterior rim of glenoid fossa
  2. Defect at the posterolateral head
  3. Complications of recurrent dislocations of SH seen on the humeral head

A. Bankart Fracture/Lesion
B. Hill-Sachs compression

A
  1. A
  2. B
  3. B

NOTE: Most of the time if you have a Bankart lesion, you don’t have a Hill-Sachs defect.

81
Q

Advanced Imaging Evaluation

Modified TF
A. Oblique cuts are done to be able to follow the anatomical structure, especially the supraspinatus muscle and tendon, along their axes.
B. It is also easier to diagnose pathologies if the structure is seen in parallel or perpendicular to its natural orientation.

A

TT

NOTE: If the scapula is viewed from the top, the scapula looks internally rotated, so the cuts should be aligned at the scapula, allowing you to see the entire length of the supraspinatus. If more anterior position: the subscapularis is seen, if more lateral: the infraspinatus is seen.