1. General Principles & Basic Science MCQs

A 32-year-old woman presents with an expansive, purely lytic lesion in the distal radius extending to the subchondral bone. Biopsy confirms a Giant Cell Tumor (GCT). For an unresectable or recurrent GCT, which targeted medical therapy is most appropriate?

Which of the following best describes the 'neurovascular theory' in the pathogenesis of a Charcot neuropathic joint?

A 5-year-old boy presents with daily spiking fevers, a generalized salmon-pink macular rash, hepatosplenomegaly, and severe polyarthritis. Laboratory tests show markedly elevated ferritin, ESR, and CRP, but negative ANA and RF. Which of the following is the most likely diagnosis?

Which subtype of Juvenile Idiopathic Arthritis (JIA) carries the highest risk for developing asymptomatic anterior uveitis, thereby requiring the most frequent ophthalmologic screening?

A 32-year-old woman presents with knee pain. Radiographs reveal an eccentric, purely lytic, epiphyseal lesion extending to the subchondral bone of the proximal tibia. Biopsy confirms multinucleated giant cells in a background of mononuclear stromal cells. Which targeted therapy acts as a RANKL inhibitor and is indicated for advanced or unresectable forms of this tumor?

A 4-year-old girl is diagnosed with oligoarticular Juvenile Idiopathic Arthritis (JIA). Her ANA is positive and rheumatoid factor is negative. Which of the following is the most appropriate screening protocol for the most common extra-articular complication in this patient?

A 6-year-old boy presents with daily spiking fevers up to 39.5°C, a transient salmon-pink macular rash, and hepatosplenomegaly. He also has bilateral knee effusions. Laboratory tests show elevated ferritin and leukocytosis. What is the most likely diagnosis?

A 32-year-old woman presents with knee pain. Radiographs reveal an eccentric, expansile lytic lesion in the distal femoral epiphysis extending to the articular surface. Biopsy shows multinucleated giant cells in a stroma of mononuclear cells. Which of the following is the most appropriate targeted medical therapy?

A 65-year-old man presents with a massively enlarged, painless knee. He has a history of untreated syphilis in his youth. Radiographs reveal severe joint destruction and large osteophytes. Neurological exam shows loss of proprioception and a positive Romberg sign. Which of the following is the most likely pathophysiological mechanism for his joint destruction?

A 7-year-old boy with systemic JIA suddenly deteriorates, developing lethargy, unremitting fever, and mucosal bleeding. Laboratory findings show profound cytopenias, a rapidly falling erythrocyte sedimentation rate (ESR), hypofibrinogenemia, and markedly elevated serum ferritin. What is the most likely diagnosis?

A 65-year-old man presents with severe back pain and fatigue. Radiographs show multiple "punched-out" lytic lesions in his skull and vertebral bodies. Laboratory studies reveal hypercalcemia, anemia, and an M-spike on serum protein electrophoresis. The osteolytic lesions in this disease are primarily mediated by the upregulation of which factor?

A 4-year-old girl with ANA-positive oligoarticular Juvenile Idiopathic Arthritis (JIA) presents for routine follow-up. Which of the following represents the most critical routine screening recommendation for this patient?

A 32-year-old male presents with painless swelling and instability of his left shoulder. He has noted recent burns on his hands that he did not feel. Imaging shows severe joint destruction.

What is the most likely underlying pathophysiology?

A 30-year-old female presents with a lytic lesion in the distal femur extending to the subchondral bone. Biopsy confirms a Giant Cell Tumor. Prior to extended intralesional curettage, the surgeon administers denosumab. What is the mechanism of action of denosumab?

A 45-year-old male presents with painless swelling and severe crepitus in his right shoulder. He has a history of cervical syringomyelia. Radiographs show severe joint destruction, debris, and dislocation.

What is the primary pathophysiologic mechanism for this joint destruction?

A 32-year-old woman presents with a large, lytic, epiphyseal-metaphyseal lesion of her distal radius. Biopsy confirms a Giant Cell Tumor of bone (GCTB). She is started on Denosumab prior to surgical intervention. What is the mechanism of action of this medication?

A 68-year-old female sustains a displaced four-part proximal humerus fracture after a fall. The primary blood supply to the articular segment is severely compromised, placing her at high risk for avascular necrosis. The critical vessel providing this predominant blood supply typically traverses which of the following anatomic spaces?

A 35-year-old male undergoes an extensive open surgical release for severe post-traumatic elbow stiffness. To prevent the recurrence of heterotopic ossification (HO), the multidisciplinary team recommends a single dose of 700 cGy of radiation therapy to be administered within 24 hours postoperatively. At what cellular level does this radiation therapy primarily act to prevent the formation of heterotopic bone?