1. General Principles & Basic Science MCQs

A 62-year-old smoker with a 2-day history of cough and fever is admitted with a diagnosis of left-sided pneumonia and left-sided pleural effusion up to the 6th intercostal space. Pleural fluid is aspirated and sent for tests. Which one of the following is an indication for inserting a chest drain?

A 50-year-old man with poorly controlled diabetes presents with a chronic, non-healing ulcer on the plantar aspect of his foot. Probe-to-bone testing is positive. Which imaging modality is the most specific for confirming osteomyelitis in this setting?

A 72-year-old woman with a recent distal radius fracture has a DEXA T-score of -3.1 at the lumbar spine. She is started on teriparatide therapy. What is the primary mechanism of action of this medication?

A 55-year-old man develops acute monoarticular knee pain and profound swelling on postoperative day 3 following a lumbar fusion. Joint aspirate reveals a WBC count of 45,000 cells/mm3 and negatively birefringent needle-shaped crystals. Which medication is most appropriate for the immediate acute management of this joint?

An 82-year-old woman falls and sustains a displaced femoral neck fracture. She takes warfarin for atrial fibrillation, and her admission INR is 3.5. Which of the following is the most appropriate agent to reverse her coagulopathy for urgent surgical intervention?

A 65-year-old man is prescribed rivaroxaban for deep vein thrombosis (DVT) prophylaxis following a total hip arthroplasty. What is the mechanism of action of this medication?

A 45-year-old woman presents with diffuse bone pain and proximal muscle weakness. Laboratory studies show low normal serum calcium, low phosphorus, elevated alkaline phosphatase, and elevated parathyroid hormone. Radiographs reveal radiolucent bands perpendicular to the bone cortex. What is the most likely diagnosis?

A 68-year-old man presents with progressive bowing of his right tibia and an increasing hat size. Radiographs of the skull show "cotton wool" exudates, and the tibia shows pronounced cortical thickening. Which of the following best describes the classic histologic appearance of his bone?

A 12-year-old boy with sickle cell disease presents with fever, severe left thigh pain, and a limp. An MRI shows diffuse bone marrow edema with a subperiosteal fluid collection. Blood cultures are drawn. While Staphylococcus aureus is the most common overall cause, which organism is characteristically associated with this specific patient population?

A 14-year-old boy with Hemophilia A presents with recurrent severe hemarthroses of the right knee. Which of the following describes the primary mechanism of joint destruction in hemophilic arthropathy?

A 4-year-old boy with a history of multiple low-energy fractures presents with a new diaphyseal femur fracture. On examination, he has blue sclerae and mild hearing loss. Radiographs show generalized osteopenia and severe bowing of the long bones. Which class of medication is commonly used to decrease fracture incidence in this condition?

Which of the following mechanical factors provides the primary stimulus for secondary bone healing characterized by robust callus formation?

Which biomechanical property of titanium makes it highly advantageous for use in uncemented orthopedic implants compared to stainless steel or cobalt-chrome alloys?

Which zone of normal articular cartilage contains the highest concentration of water and has collagen fibers oriented parallel to the joint surface to resist shear forces?

A 32-year-old woman presents with a radiolucent, eccentric, epiphyseal-metaphyseal lesion in her proximal tibia. Biopsy shows multinucleated giant cells admixed with mononuclear stromal cells. If systemic therapy is indicated, which of the following mechanisms best describes the targeted biologic agent commonly used?

A neonate is evaluated for multiple fractures and cranial nerve palsies. Radiographs show diffusely dense, 'bone-within-bone' appearance in the vertebrae and long bones. A defect in which of the following enzymes or proteins is most likely responsible for this condition?

A 65-year-old man presents with progressive bowing of his right femur and increasing head size. Laboratory studies show markedly elevated alkaline phosphatase with normal calcium and phosphorus. Histological examination of the affected bone is most likely to show which of the following?

A newborn is noted to have rhizomelic shortening of the limbs, frontal bossing, and midface hypoplasia. Genetic testing reveals a gain-of-function mutation in the FGFR3 gene. Which of the following best describes the fundamental defect in bone formation in this condition?

A 36-year-old primary schoolteacher who works in a deprived area of London presents with increasing shortness of breath accompanied by sudden-onset, right-sided pleuritic chest pain. She gives a history of influenza for a few days before this acute presentation and also says she suffered a pulmonary embolus 2 years ago while taking the contraceptive pill (and describes her pain as identical to that she experienced on that occasion). On further questioning, it transpires that her mother had suffered from recurrent deep vein thrombosis. Arterial blood gases reveal a pO2 of 7.2 kPa on a non-rebreather mask, with a pCO2 of 3.2 kPa. Her chest X-ray reveals a wedge-shaped area of consolidation affecting her right middle and lower lobes. The white blood cell count is normal. Which diagnosis fits best with this clinical picture?

A 60-year-old patient was referred with a 1-year history of persistent cough productive of mucopurulent sputum throughout the year. He has been treated by his GP for recurrent chest infections. What is the most likely diagnosis?