CCEP CCEP Radiology & Imaging for Extremities 2 — Questions and Answers
Question 1: A 'sail sign' on a lateral elbow radiograph is caused by which finding?
- Osteochondral defect
- Anterior fat pad elevation from joint effusion (Correct answer)
- Radial head fracture fragment
- Medial epicondyle avulsion
Correct answer: Anterior fat pad elevation from joint effusion
The sail sign is elevation of the anterior fat pad on a lateral elbow X-ray, indicating joint effusion often from an occult fracture such as a radial head fracture.
Question 2: Which radiographic measurement assesses acetabular coverage of the femoral head and identifies hip dysplasia?
- Cobb angle
- Center-edge angle of Wiberg (Correct answer)
- Bohler's angle
- Neck-shaft angle
Correct answer: Center-edge angle of Wiberg
The center-edge angle of Wiberg measures acetabular coverage of the femoral head; values below 25° indicate insufficient coverage consistent with dysplasia.
Question 3: Which extremity condition benefits most from real-time dynamic ultrasound evaluation?
- Stress fractures
- Bone tumors
- Tendon tears and dynamic tendon instability (Correct answer)
- Cartilage thickness mapping
Correct answer: Tendon tears and dynamic tendon instability
Ultrasound allows dynamic real-time imaging of tendons during movement, revealing tears, subluxation, and tendon instability not apparent on static imaging.
Question 4: A 'light bulb' sign on an AP shoulder radiograph suggests which diagnosis?
- Glenohumeral arthritis
- Posterior shoulder dislocation (Correct answer)
- Calcific rotator cuff tendinitis
- Acromial fracture
Correct answer: Posterior shoulder dislocation
In posterior shoulder dislocation, the humeral head is locked in internal rotation, creating a symmetric 'light bulb' appearance on the AP view.
Question 5: Bohler's tuber joint angle on a lateral calcaneus X-ray normally measures which range?
- 5–10°
- 20–40° (Correct answer)
- 45–60°
- 60–75°
Correct answer: 20–40°
Bohler's angle normally measures 20–40°; a decrease below 20° suggests a calcaneal compression fracture with collapse of the posterior facet.
Question 6: Adhesive capsulitis (frozen shoulder) demonstrates which characteristic finding on shoulder arthrography?
- Contrast extravasation through a full-thickness cuff tear
- Reduced joint volume and contracted capsule (rim sign) (Correct answer)
- Superior labral detachment
- Hill-Sachs filling defect
Correct answer: Reduced joint volume and contracted capsule (rim sign)
Adhesive capsulitis shows markedly reduced joint volume on arthrography with a contracted capsule and reduced contrast filling known as the rim sign.
CCEP CCEP Radiology & Imaging for Extremities 2
A 'sail sign' on a lateral elbow radiograph is caused by which finding?