S2_L3 Anatomy & Radiologic Evaluation of the Elbow Flashcards
MRI Image Interpretation: Soft Tissue & Synovial Tissues
- Triceps tendon ruptures that are less common
- Common extensor tendon injuries (Tennis Elbow)
- Bicipitoradial bursa may be assessed for inflammation
A. Anterior compartment
B. Lateral compartment
C. Medial compartment
D. Posterior compartment
- D
- B
- A
MRI Image Interpretation: Soft Tissue & Synovial Tissues
- Imaging must be done with the elbow in both flexion and extension
to check patency of ligaments and muscles - Common flexor tendon injuries (Little Leaguer’s Elbow)
A. Anterior compartment
B. Lateral compartment
C. Medial compartment
D. Posterior compartment
- D
- C
MRI Image Interpretation: Soft Tissue & Synovial Tissues
- Avulsions at the attachment sites will show edema and hemorrhage extending into the defect
- Partial tears are identified by changes in tendon girth and an abnormally high signal within the tendon on T2 weighted images
A. Anterior compartment
B. Lateral compartment
C. Medial compartment
D. Posterior compartment
- B
- A
MRI Image Interpretation: Soft Tissue & Synovial Tissues
Modified TF
A. A complete biceps tendon rupture is the most common rupture at the elbow, defined by a gap between the retracted tendon ends.
B. This rupture is located in the anterior compartment.
TT
MRI: Soft Tissue & Synovial Tissues (Medial Compartment)
Modified TF
A. MCL ligament tears are associated in throwing/pitching athletes.
B. Axial views are best to identify torn fibers and abnormal signals in the normally linear low signal ligament.
TF
B: Coronal views are best to identify torn fibers and abnormal signals in the normally linear low signal ligament.
MRI: Soft Tissue & Synovial Tissues (Medial Compartment)
Modified TF
A. Findings in medial epicondylitis include tendon degeneration, tendon disruption, partial tears, and muscle strain.
B. Coronal and axial imaging show possible alterations in tendon thickness, discontinuity of torn fibers, and low signals associated with inflammation.
TF
B: Coronal and axial imaging show possible alterations in tendon thickness, discontinuity of torn fibers, and high signals associated with inflammation.
MRI: Soft Tissue & Synovial Tissues (Posterior Compartment)
Modified TF
A. An olecranon burisitis occurs when the triceps tendon abnormally glides over the medial epicondyle which may cause the ulnar nerve to dislocate.
B. A snapping triceps tendon is identified as a high signal focal collection of fluid over the olecranon and may be associated with gout, a tear of the triceps muscle, or student’s elbow (repetitive pressure on the olecranon).
FF
A: A snapping triceps tendon occurs when the triceps tendon abnormally glides over the medial epicondyle which may cause the ulnar nerve to dislocate.
B: An olecranon bursitis is identified as a high signal focal collection of fluid over the olecranon and may be associated with gout, a tear of the triceps muscle, or student’s elbow (repetitive pressure on the olecranon).
MRI: Soft Tissue & Synovial Tissues (Lateral Compartment)
Modified TF
A. Sprains of the LCL are seen as a thickened/thinned ligament with a high signal surrounding it.
B. On the other hand, complete tears will show discontinuity of the fibers.
TT
MRI: Soft Tissue & Synovial Tissues (Posterior Compartment)
Modified TF
A. Tears of the LCL are less common, but are seen in association with lateral epicondylitis and/or elbow dislocation;
it is compromised due to biomechanical changes secondary to other lateral elbow conditions.
B. MRI findings in lateral epicondylitis are the same as medial epicondylitis.
TT
MRI Image Interpretation of the Elbow
It is the “footprint” of the injury on MRI
A. Alignment of anatomy
B. Bone signal
C. Edema
D. Soft tissue and synovial tissue
C. Edema
Advanced Imaging Evaluation: CT Scan & MRI
- Check for occult fractures not seen by conventional radiographs
- Assess the radial head and its articulation to the capitulum
- Check for bony disruptions at sites of tendon attachments
A. Alignment on CT Scan
B. Alignment of anatomy on MRI
- B
- A
- B
Advanced Imaging Evaluation: CT Scan & MRI
- On axial slices, check the humeroulnar and humeroradial articulations
- Check for associated bone injury that may have resulted during dislocation or trauma
- On sagittal slices, assess the configuration of the ulnar trochlear notch and its articulation to the trochlea.
A. Alignment on CT Scan
B. Alignment of anatomy on MRI
- A
- B
- A
Advanced Imaging Evaluation: CT Scan & MRI
Check for deviations of the geography of bones and joint articulations that signal fracture, dislocation, or bone destruction.
A. Alignment on CT Scan
B. Alignment of anatomy on MRI
A. Alignment on CT Scan
Advanced Imaging Evaluation: CT Scan & MRI
- Assess for bony destruction signifying disease or infection
- Define radiographically ambiguous or occult fractures not seen in x-ray
- Check for trabeculae, osseous cysts, cortical hypertrophy, sclerosis, or destruction
A. Bone Density on CT Scan
B. Bone Signal on MRI
- A
- B
- A
Advanced Imaging Evaluation: CT Scan & MRI
- Check for bone bruises or marrow edema, stress fractures, and osteochondral injuries.
- As in radiographs, cortical bone is most dense, while cancellous bone is seen as less dense in the medullary cavity.
A. Bone Density on CT Scan
B. Bone Signal on MRI
- B
- A
Advanced Imaging Evaluation: CT Scan & MRI
- Utilize T2 sequence with fat compression
- Identification of free fragments
- Assess for effusions, sweilling, bursitis, muscle atrophy
A. Cartilage / Joint Spaces on CT Scan
B. Soft tissues on CT Scan
C. Edema on MRI
- C
- A
- B
Advanced Imaging Evaluation: CT Scan & MRI
- Assess the humeroradial and humeroulnar joint spaces for smooth chondral surfaces
- Check for presence of edema due to inflammatory process of injuries in all tissues (both bony and soft)
A. Cartilage / Joint Spaces on CT Scan
B. Soft tissues on CT Scan
C. Edema on MRI
- A
- C
Advanced Imaging Evaluation: CT Scan & MRI
TRUE OR FALSE: Osteochondral lesions are more common at the capitulum and radial head, as these are the commonly damaged areas/ structures surrounded by cartilage.
True
CT Scan of the Elbow: Soft Tissues
- Biceps mucscle and tendon
- Common flexor tendon originating on the medial epicondyle
- Extensor supinator groups of muscle
A. Anterior soft tissues
B. Posterior soft tissues
C. Lateral soft tissues
D. Medial soft tissues
- A
- D
- C
CT Scan of the Elbow: Soft Tissues
- Brachioradialis
- Brachialis muscle and tendon
- Anconeus muscle
A. Anterior soft tissues
B. Posterior soft tissues
C. Lateral soft tissues
D. Medial soft tissues
- C
- A
- B
CT Scan of the Elbow: Soft Tissues
- Flexor-pronator group of muscles
- Triceps muscle
- Common extensor tendon originating from the lateral epicondyle
A. Anterior soft tissues
B. Posterior soft tissues
C. Lateral soft tissues
D. Medial soft tissues
- D
- B
- C
Basic MRI Protocol for Image Interpretation of the Elbow
- Inversion Recovery (IR)
- GRE (Gradient Echo)
- T2 weighted (with fat suppression)
A. Define the anatomy
B. Detect abnormal fluid
- B
- A
- B
NOTE: Chronic injuries may not have edema unlike acute injuries and aberrations in anatomy need to be considered
Basic MRI Protocol for Image Interpretation of the Elbow
- T1 weighted
- Proton Density (PD)
A. Define the anatomy
B. Detect abnormal fluid
- A
- A
MR Arthrography
Modified TF
A. MR arthrography is useful at the elbow to detect tears of the collateral ligaments and defects of the cartilaginous surfaces.
B. The contrast produces distension of the joint that allows for better visualization of smaller structures.
TT
Case: MD is thinking of unstable lesion or osteochondral fractures of the capitulum as the diagnosis for patient G.N., however, routine radiographs were non-diagnostic. What advanced imaging can be performed to aid in the diagnosis?
MR Arthrography
Since it is used in diagnosing unstable lesions or osteochondral fractures of the capitulum if radiographs are non-diagnostic.
Routine Radiologic Evaluation of the Forearm: Lateral View
Modified TF
A. The patient’s elbow is flexed and forearm is resting in its ulnar border supinated ~35º (FA is in midprone position).
B. This view demonstrates the elbow, the entire length of the radius and ulna, and the wrist.
FT
A: The patient’s elbow is flexed and forearm is resting in its ulnar border supinated ~45º (FA is in midprone position).