C. Giant cell tumor
2 Which disease is characterized by periarticular tendinous thickening, thickened synovium, and large erosions?
A. Rheumatoid arthritis
B. Hemophilic arthropathy
3 Which of the following diseases most likely manifests as a diffuse bony sclerosis?
C. Multiple myeloma
D. Vitamin C deficiency
4 A 57-year-old female presents with lower extremity pain. Based on the images below, which of the following is the next most appropriate study?
A. Cervical spine radiograph
B. Lumbar spine MRI
C. Abdomen and pelvis CT
D. Chest radiograph
5 Sagittal MR images of the cervical spine of a 16-month-old patient demonstrate which of the following osseous findings?
A. Leukemic infiltration
B. Postradiation changes
D. Red marrow conversion
6 Which of the following best describes the imaging appearance of sarcoidosis in the hand?
A. Soft tissue swelling and periarticular erosions with overhanging edges
B. Periarticular osteoporosis and marginal erosions
C. Lace-like trabecular pattern and cortical erosions
D. Joint space narrowing and subluxations
7a The radiograph of the pelvis below demonstrates the imaging findings characteristic of what diagnosis?
A. Slipped capital femoral epiphysis
7b The MR images below depict what sign that is typically associated with osteonecrosis of the hip?
A. Crescent sign
B. Joint effusion sign
C. Increased T2 cortex signal sign
D. Double-line sign
8a The following radiograph demonstrates the blade of grass sign, characteristic of which of the following pathologies?
A. Radiation osteonecrosis
B. Paget disease
C. Acute myeloid leukemia
8b Which of the following is the best definition for the term “blade of grass”?
A. Site of sarcomatous degeneration
B. Site of pathologic fracture
C. Thickened cortex in long bones
D. Sharp demarcation in long bones between lesion and normal bone
9 A 10-year-old male presents with thickening of the skin of the face. Radiographs of the forearm demonstrate periosteal reaction of the distal radial and ulnar metaphyses. These findings are most characteristic of which of the following diseases?
A. Primary hypertrophic osteoarthropathy
C. Juvenile idiopathic arthritis
ANSWERS AND EXPLANATIONS
1 Answer B. Neoplastic complications associated with Paget disease are relatively rare and have been reported to occur in <1% of cases with limited skeletal involvement and up to 5% to 10% of cases with widespread skeletal involvement. Sarcomatous transformation is the most common manifestation of a neoplastic complication. The most common type of sarcomatous transformation is osteosarcoma. Imaging findings that would be concerning for sarcomatous transformation include aggressive osteolysis, cortical destruction, and an associated soft tissue mass.