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ACEM Primary practice questions

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Question 1Emergency Medicine

A 24-year-old man sustains a stab wound to the right anterior chest. He is alert, talking, and haemodynamically stable, but there is absent breath sound on the right with hyper-resonance to percussion. Which is the most appropriate immediate management?

  1. Emergency department thoracotomy
  2. Immediate needle decompression of the right chest
  3. Urgent chest drain insertion on the right Correct answer.
  4. Portable chest radiograph before any intervention

Explanation

A stable patient with a suspected simple pneumothorax after penetrating trauma is managed with tube thoracostomy, which both diagnoses and treats. Needle decompression is reserved for tension physiology or a crashing patient, and imaging should not delay decompression when tension is suspected.

Question 2Emergency Medicine

Which finding most reliably distinguishes tension pneumothorax from a simple pneumothorax on clinical examination?

  1. Reduced ipsilateral breath sounds
  2. Tracheal deviation toward the affected side
  3. Hyper-resonance to percussion
  4. Haemodynamic compromise with distended neck veins Correct answer.

Explanation

Tension physiology causes obstructive shock with hypotension, tachycardia, and raised central venous pressure, which is the key discriminator. Hyper-resonance and reduced breath sounds occur in any pneumothorax, and tracheal deviation is a late and unreliable sign.

Question 3Emergency Medicine

A 30-year-old woman is 32 weeks pregnant and presents with a 2-hour history of painless bright red vaginal bleeding. The uterus is soft and non-tender, and the fetal heart rate is 150 bpm. Which is the most appropriate initial investigation?

  1. Transabdominal ultrasound Correct answer.
  2. Speculum examination with clot evacuation
  3. Digital vaginal examination
  4. Formal cervical assessment in theatre

Explanation

Painless antepartum haemorrhage suggests placenta praevia, and transabdominal ultrasound is the safe initial localising investigation. Digital or speculum examination risks provoking catastrophic haemorrhage until praevia is excluded.

Question 4Emergency Medicine

Which characteristic best differentiates pre-eclampsia from gestational hypertension?

  1. Blood pressure above 140/90 mmHg after 20 weeks
  2. Onset in the third trimester
  3. Resolution within 6 weeks postpartum
  4. New proteinuria or end-organ dysfunction Correct answer.

Explanation

Pre-eclampsia is defined by new hypertension after 20 weeks plus proteinuria or maternal end-organ dysfunction. Gestational hypertension has elevated blood pressure without these features.

Question 5Emergency Medicine

A 68-year-old man presents with sudden painless loss of vision in one eye described as a curtain descending. Fundoscopy shows a pale retina with a cherry-red spot. What is the most appropriate immediate management?

  1. Immediate intravenous corticosteroids
  2. Reassurance and outpatient review in one week
  3. Topical beta-blocker and urgent ophthalmology review
  4. Ocular massage and urgent ophthalmology referral Correct answer.

Explanation

This is a central retinal artery occlusion, a time-critical ocular emergency; ocular massage and immediate specialist referral aim to dislodge or improve perfusion while systemic causes are sought. Corticosteroids are for giant cell arteritis-related ischaemia, not routine CRAO.

Question 6Emergency Medicine

Which finding is most consistent with acute angle-closure glaucoma?

  1. A small pupil that reacts briskly to light
  2. Painless visual field loss
  3. Bilateral watery discharge with normal intraocular pressure
  4. A fixed mid-dilated pupil with a hazy cornea Correct answer.

Explanation

Acute angle closure presents with a fixed, mid-dilated pupil, corneal oedema causing haze, severe pain, and raised intraocular pressure. A reactive pupil and painless field loss suggest other pathology such as open-angle glaucoma or optic neuropathy.

Question 7Emergency Medicine

A 55-year-old man with known atrial fibrillation presents with sudden onset of severe abdominal pain out of proportion to examination findings. Which diagnosis should be most strongly suspected?

  1. Acute pancreatitis
  2. Acute mesenteric ischaemia Correct answer.
  3. Acute cholecystitis
  4. Perforated peptic ulcer

Explanation

Pain out of proportion to examination in a patient with an embolic risk (atrial fibrillation) suggests acute mesenteric ischaemia, where early examination is often deceptively benign. Prompt CT angiography and surgical or interventional review are required.

Question 8Emergency Medicine

Which is the most appropriate initial fluid resuscitation strategy for an adult with suspected early septic shock?

  1. Hypertonic saline bolus
  2. 500 mL of crystalloid over 24 hours
  3. Immediate packed red cell transfusion
  4. 30 mL/kg of balanced crystalloid given rapidly Correct answer.

Explanation

Early septic shock is managed with an initial rapid bolus of balanced crystalloid, typically 30 mL/kg, followed by reassessment of perfusion. Blood transfusion and hypertonic saline are reserved for specific indications.

Question 9Emergency Medicine

A 3-year-old child presents with drooling, a muffled voice, and a barking cough with stridor and high fever. Which is the most appropriate initial action?

  1. Obtain a lateral neck radiograph before any handling
  2. Keep the child calm and allow a position of comfort Correct answer.
  3. Inspect the throat with a tongue depressor
  4. Attempt immediate endotracheal intubation

Explanation

The presentation suggests epiglottitis, an airway emergency where agitation can precipitate complete obstruction; the child should be kept calm and definitive airway management arranged in a controlled setting. Throat inspection and forced positioning are dangerous.

Question 10Emergency Medicine

A 6-month-old infant is brought in with a 3-day history of vomiting and diarrhoea, sunken eyes, and a capillary refill of 4 seconds. Which fluid deficit estimate best corresponds to severe dehydration?

  1. 5 to 10% of body weight
  2. Less than 3% of body weight
  3. 3 to 5% of body weight
  4. More than 10% of body weight Correct answer.

Explanation

Severe dehydration in infants corresponds to a deficit greater than 10% of body weight, with signs such as delayed capillary refill, sunken eyes, and lethargy. Mild and moderate dehydration correspond to smaller estimated deficits.

Question 11Emergency Medicine

Which is the most appropriate first-line antidote for a patient with severe organophosphate poisoning presenting with bradycardia, bronchorrhoea, and miosis?

  1. N-acetylcysteine
  2. Naloxone
  3. Flumazenil
  4. Atropine Correct answer.

Explanation

Atropine antagonises the muscarinic effects of excess acetylcholine in organophosphate poisoning, titrated to drying of secretions. Pralidoxime may be added for nicotinic effects but atropine is the immediate priority.

Question 12Emergency Medicine

A patient presents 6 hours after ingesting a potentially toxic dose of paracetamol. Which investigation best guides initiation of antidotal therapy?

  1. Urinary toxicology screen
  2. Serum amylase
  3. Liver function tests alone
  4. Serum paracetamol concentration plotted against time since ingestion Correct answer.

Explanation

The need for N-acetylcysteine is determined by plotting the serum paracetamol concentration against time from ingestion on the treatment nomogram. Liver function tests may be normal early and do not guide initial antidote decisions.

Question 13Emergency Medicine

Which feature most strongly suggests a diagnosis of serotonin syndrome rather than neuroleptic malignant syndrome?

  1. Bradyreflexia with hypothermia
  2. Onset over several days after starting a dopamine antagonist
  3. Recent use of a serotonergic agent with clonus and hyperreflexia Correct answer.
  4. Rigidity with markedly raised creatine kinase

Explanation

Serotonin syndrome typically follows serotonergic drug use and is characterised by neuromuscular hyperactivity such as clonus and hyperreflexia. Neuroleptic malignant syndrome follows dopamine antagonists and features lead-pipe rigidity with a slower onset.

Question 14Emergency Medicine

A 70-year-old man presents with a 2-hour history of sudden painless monocular visual loss. Which finding on fundoscopy supports a retinal artery occlusion rather than a retinal vein occlusion?

  1. Disc swelling with a macular star
  2. Peripheral retinal tears
  3. A pale retina with a cherry-red macula Correct answer.
  4. Widespread retinal haemorrhages in all quadrants

Explanation

Central retinal artery occlusion produces retinal pallor with a cherry-red spot at the fovea, reflecting preserved choroidal perfusion. Retinal vein occlusion instead shows diffuse flame haemorrhages and disc swelling.

Question 15Emergency Medicine

Which is the most appropriate initial management for a patient with suspected acute aortic dissection who is haemodynamically stable?

  1. Rapid blood pressure control with a beta-blocker and analgesia Correct answer.
  2. Intravenous thrombolysis
  3. Immediate anticoagulation with heparin
  4. Fluid loading to raise blood pressure

Explanation

In acute aortic dissection, reducing heart rate and blood pressure reduces aortic wall stress, so a beta-blocker plus analgesia is the immediate priority. Anticoagulation and thrombolysis are contraindicated because they worsen bleeding into the false lumen.

Question 16Emergency Medicine

Which ECG finding is most characteristic of hyperkalaemia?

  1. Peaked T waves with a widening QRS Correct answer.
  2. Prominent U waves
  3. Saddle-shaped ST elevation
  4. Prolonged QT interval

Explanation

Hyperkalaemia classically produces tall peaked T waves and, as it worsens, QRS widening and sine-wave morphology. U waves and prolonged QT suggest hypokalaemia or hypocalcaemia respectively.

Question 17Emergency Medicine

A patient with severe hyponatraemia and seizures requires emergency correction. Which is the most appropriate initial treatment?

  1. Intravenous furosemide alone
  2. Rapid correction with 3% hypertonic saline to raise sodium by 10 mmol/L in the first hour Correct answer.
  3. Fluid restriction alone
  4. Slow correction over 72 hours regardless of symptoms

Explanation

Severe symptomatic hyponatraemia with seizures requires immediate hypertonic saline to raise serum sodium by a few mmol/L rapidly, aiming to relieve symptoms while avoiding overcorrection. Correction limits of around 10 mmol/L in 24 hours reduce the risk of osmotic demyelination.

Question 18Emergency Medicine

Which is the most appropriate first-line treatment for a patient with anaphylaxis?

  1. Intramuscular adrenaline into the anterolateral thigh Correct answer.
  2. Intravenous antihistamine
  3. Nebulised salbutamol
  4. Oral corticosteroids

Explanation

Intramuscular adrenaline is the first-line treatment for anaphylaxis, given early into the anterolateral thigh. Antihistamines and corticosteroids are adjuncts that do not reverse airway or circulatory compromise.

Question 19Emergency Medicine

A young woman presents with sudden onset pleuritic chest pain and dyspnoea 3 days after starting a combined oral contraceptive. Which finding most increases the pre-test probability of pulmonary embolism?

  1. Productive cough with fever
  2. Bilateral ankle oedema
  3. Unilateral leg swelling Correct answer.
  4. Wheezing with a history of asthma

Explanation

Unilateral leg swelling suggests deep vein thrombosis, a major risk factor for pulmonary embolism. The combination of oestrogen use and clinical signs of DVT raises the pre-test probability substantially.

Question 20Emergency Medicine

Which is the most appropriate initial investigation for a haemodynamically stable patient with suspected pulmonary embolism and a high pre-test probability?

  1. Echocardiography
  2. Chest radiograph alone
  3. D-dimer
  4. CT pulmonary angiography Correct answer.

Explanation

In a stable patient with high clinical probability, CT pulmonary angiography is the diagnostic test of choice. D-dimer is useful only to exclude embolism in low or intermediate probability patients.

Question 21Emergency Medicine

A 45-year-old man presents with a generalised tonic-clonic seizure lasting 4 minutes. Which is the most appropriate first-line pharmacological treatment?

  1. Intramuscular haloperidol
  2. Intravenous benzodiazepine Correct answer.
  3. Oral carbamazepine
  4. Intravenous phenytoin

Explanation

A benzodiazepine is the first-line agent for terminating convulsive status epilepticus, with a second-line agent such as phenytoin added if seizures persist. Phenytoin is not used as the initial agent.

Question 22Emergency Medicine

Which feature best distinguishes a syncopal episode from a generalised seizure?

  1. A postictal period of confusion lasting several minutes Correct answer.
  2. A history of triggers such as prolonged standing
  3. A rapid recovery with prompt return to baseline
  4. Limb jerking during the event

Explanation

A postictal confusional state lasting minutes is characteristic of a generalised seizure, whereas recovery from syncope is typically rapid and complete. Limb jerking and triggers can occur in both, making them less reliable discriminators.

Question 23Emergency Medicine

A patient presents with a Glasgow Coma Scale score of 8 following a head injury. Which is the most appropriate airway management?

  1. Insertion of a nasogastric tube without airway protection
  2. Observation with serial GCS monitoring
  3. Nasopharyngeal airway alone
  4. Immediate endotracheal intubation Correct answer.

Explanation

A GCS of 8 or less indicates an unprotected airway and warrants definitive airway control with endotracheal intubation. Observation and simple adjuncts are inadequate when airway reflexes are compromised.

Question 24Emergency Medicine

Which finding on CT imaging best indicates a surgically significant extradural haematoma?

  1. Bilateral small frontal contusions
  2. A crescentic collection crossing suture lines
  3. A biconvex collection limited by suture lines Correct answer.
  4. Diffuse subarachnoid blood in the basal cisterns

Explanation

Extradural haematomas arise from middle meningeal artery injury and appear as biconvex collections that do not cross suture lines. Subdural haematomas are crescentic and can cross sutures.

Question 25Emergency Medicine

A 25-year-old man presents after a high-speed motorcycle collision with hypotension, tachycardia, and a distended abdomen. Which is the most appropriate immediate management?

  1. Focused assessment with sonography and urgent blood transfusion Correct answer.
  2. Oral contrast CT scan
  3. Observation with serial haemoglobin
  4. Diagnostic peritoneal lavage after stabilisation

Explanation

A hypotensive trauma patient with abdominal distension likely has intra-abdominal haemorrhage; rapid bedside ultrasound and blood product resuscitation guide urgent surgical intervention. CT and observation delay definitive haemorrhage control.

Question 26Emergency Medicine

A 28-year-old man is brought to the emergency department after a witnessed collapse. He has a generalised tonic-clonic seizure lasting 5 minutes. Which is the most appropriate first-line pharmacological agent?

  1. Oral carbamazepine
  2. Intravenous phenytoin
  3. Intravenous lorazepam Correct answer.
  4. Intramuscular haloperidol

Explanation

Status epilepticus is terminated with a benzodiazepine first, since GABA-A potentiation acts within minutes to stop ongoing seizure activity. Phenytoin is a second-line agent used after benzodiazepines fail to control the seizure.

Question 27Emergency Medicine

A 65-year-old woman has a blood glucose of 1.8 mmol/L and is drowsy but able to swallow safely. Which is the most appropriate immediate treatment?

  1. Intravenous 50% dextrose
  2. Intramuscular glucagon
  3. Subcutaneous insulin
  4. Oral glucose gel Correct answer.

Explanation

In a hypoglycaemic patient who can protect the airway and swallow, oral glucose is the safest and fastest route. Intravenous dextrose is reserved for those unable to take oral therapy or with impaired consciousness.

Question 28Emergency Medicine

A patient is found unresponsive, apnoeic, and pulseless. Which is the first intervention in the adult cardiac arrest algorithm?

  1. Intravenous adrenaline
  2. Endotracheal intubation
  3. Defibrillation
  4. High-quality chest compressions Correct answer.

Explanation

High-quality chest compressions with minimal interruptions are the foundation of resuscitation and are started immediately on recognition of cardiac arrest. Defibrillation, drugs, and advanced airway are added according to rhythm and response.

Question 29Emergency Medicine

A 30-year-old woman develops urticaria, wheeze, and hypotension minutes after a bee sting. Which is the most appropriate first-line drug?

  1. Intramuscular adrenaline Correct answer.
  2. Oral antihistamine
  3. Nebulised salbutamol
  4. Intravenous hydrocortisone

Explanation

Intramuscular adrenaline is the first-line treatment for anaphylaxis because it reverses vasodilatation and bronchospasm rapidly. Antihistamines and corticosteroids are adjuncts and do not treat the acute airway and circulatory compromise.

Question 30Emergency Medicine

A 40-year-old man has a tension pneumothorax with severe respiratory distress and hypotension. Which is the most appropriate immediate management?

  1. Urgent chest radiograph before treatment
  2. Supplemental oxygen and observation
  3. Chest tube insertion after CT imaging
  4. Needle decompression of the affected hemithorax Correct answer.

Explanation

Tension pneumothorax is a clinical diagnosis requiring immediate decompression, as delay can cause obstructive shock and cardiac arrest. Imaging must not delay treatment in an unstable patient.

Question 31Emergency Medicine

A 24-year-old woman has sudden severe headache described as the worst of her life, with neck stiffness and photophobia. Which is the most appropriate initial investigation?

  1. Non-contrast CT head Correct answer.
  2. Carotid Doppler ultrasound
  3. Lumbar puncture immediately
  4. MRI brain with contrast

Explanation

Non-contrast CT head is the first investigation for suspected subarachnoid haemorrhage and is highly sensitive within the first 6 hours. Lumbar puncture is reserved for cases where CT is negative and clinical suspicion remains.

Question 32Emergency Medicine

A 70-year-old man has a painful, swollen, erythematous leg with fever and a rising white cell count after a minor abrasion. Which is the most appropriate initial antibiotic approach?

  1. No antibiotics unless pus is present
  2. Oral flucloxacillin Correct answer.
  3. Topical antibiotic ointment alone
  4. Intravenous ceftriaxone

Explanation

Non-purulent cellulitis is most often caused by beta-haemolytic streptococci and Staphylococcus aureus, and oral flucloxacillin is appropriate for mild to moderate cases without systemic toxicity. Intravenous therapy is reserved for severe or rapidly spreading infection.

Question 33Emergency Medicine

A patient presents with a deep partial-thickness burn to 20% of total body surface area. Which is the most appropriate initial fluid resuscitation formula?

  1. No fluids until urine output falls
  2. Colloid at 4 mL/kg/% burn
  3. Ringer's lactate at 500 mL/h regardless of weight
  4. Parkland formula using crystalloid Correct answer.

Explanation

The Parkland formula calculates crystalloid requirements as 4 mL/kg per percent total body surface area over 24 hours, with half given in the first 8 hours from the time of injury. Urine output is then used to titrate ongoing fluids.

Question 34Emergency Medicine

A 22-year-old man presents with a painful, swollen scrotum of sudden onset and a negative urine dipstick. Which is the most appropriate next step in management?

  1. Oral antibiotics and outpatient review
  2. Scrotal support and analgesia alone
  3. Urgent urological referral for exploration Correct answer.
  4. Reassurance and discharge

Explanation

Testicular torsion is a surgical emergency, and urgent exploration is required to preserve testicular viability. Doppler ultrasound should not delay surgery when clinical suspicion is high.

Question 35Emergency Medicine

A 35-year-old woman has sudden severe pleuritic chest pain and dyspnoea 3 days after starting a combined oral contraceptive. Which is the most appropriate initial investigation if she is haemodynamically stable?

  1. CT pulmonary angiogram Correct answer.
  2. Ventilation-perfusion scan
  3. D-dimer
  4. Troponin

Explanation

CT pulmonary angiography is the investigation of choice for suspected pulmonary embolism in a stable patient with a high clinical probability. D-dimer is useful only to exclude pulmonary embolism in low-probability cases.

Question 36Emergency Medicine

A 60-year-old man with known cirrhosis presents with haematemesis and hypotension. Which is the most appropriate initial pharmacological therapy in addition to resuscitation?

  1. Intravenous vitamin K alone
  2. Oral propranolol
  3. Oral lactulose
  4. Intravenous terlipressin Correct answer.

Explanation

Terlipressin reduces portal pressure and is used in suspected variceal bleeding alongside antibiotics and endoscopic therapy. Propranolol is used for prophylaxis, not acute bleeding.

Question 37Emergency Medicine

A 4-year-old child presents with a barking cough and inspiratory stridor but no drooling and no high fever. Which is the most appropriate initial management?

  1. Nebulised adrenaline and dexamethasone Correct answer.
  2. Oral antibiotics
  3. Emergency tracheostomy
  4. Immediate intubation

Explanation

Croup is managed with nebulised adrenaline for stridor at rest and a corticosteroid to reduce airway oedema. Intubation is reserved for severe airway compromise.

Question 38Emergency Medicine

A 45-year-old man has a sudden severe headache, photophobia, and a CT scan showing subarachnoid blood. Which is the most appropriate next step?

  1. Urgent neurosurgical referral and nimodipine Correct answer.
  2. Lumbar puncture
  3. Intravenous thrombolysis
  4. Discharge with analgesia

Explanation

Subarachnoid haemorrhage requires urgent neurosurgical assessment for aneurysm securing and oral nimodipine to reduce delayed cerebral ischaemia. Thrombolysis is contraindicated because it would worsen bleeding.

Question 39Emergency Medicine

A patient with suspected acute coronary syndrome has ongoing chest pain and ST elevation on ECG. Which is the most appropriate immediate reperfusion strategy if percutaneous coronary intervention is unavailable within 120 minutes?

  1. Observation with serial troponins
  2. Fibrinolytic therapy Correct answer.
  3. Coronary artery bypass grafting
  4. Oral aspirin alone

Explanation

Primary percutaneous coronary intervention is preferred when available within 120 minutes; otherwise, fibrinolysis should be given promptly in ST-elevation myocardial infarction. Aspirin is adjunctive, not reperfusion therapy.

Question 40Emergency Medicine

A 50-year-old man presents with severe epigastric pain radiating to the back, and a serum lipase three times the upper limit of normal. Which is the most appropriate initial fluid strategy?

  1. Diuretics to reduce pancreatic swelling
  2. Fluid restriction to prevent oedema
  3. Aggressive intravenous crystalloid resuscitation Correct answer.
  4. Oral fluids only

Explanation

Early aggressive crystalloid resuscitation maintains pancreatic microcirculation and reduces necrosis in acute pancreatitis. Fluid restriction and diuretics worsen hypoperfusion.

Question 41Anatomy

Which nerve is most directly at risk of injury during surgical ligation of the inferior thyroid artery close to the gland?

  1. External branch of the superior laryngeal nerve
  2. Recurrent laryngeal nerve Correct answer.
  3. Hypoglossal nerve
  4. Glossopharyngeal nerve

Explanation

The recurrent laryngeal nerve ascends in the tracheo-oesophageal groove in close relation to the inferior thyroid artery, and its branches may be divided with the artery. The external laryngeal nerve is instead related to the superior thyroid vessels.

Question 42Anatomy

The middle meningeal artery is a direct branch of which artery?

  1. Internal carotid artery
  2. Facial artery
  3. Maxillary artery Correct answer.
  4. Occipital artery

Explanation

The middle meningeal artery arises from the maxillary artery (first part) and enters the skull through the foramen spinosum. It is a classic source of extradural haemorrhage.

Question 43Anatomy

Which structure passes through the foramen ovale?

  1. Maxillary nerve
  2. Facial nerve
  3. Middle meningeal artery
  4. Mandibular nerve Correct answer.

Explanation

The mandibular division of the trigeminal nerve (V3) traverses the foramen ovale. The maxillary nerve passes through the foramen rotundum and the middle meningeal artery through the foramen spinosum.

Question 44Anatomy

The dermatome of the umbilicus is most consistently supplied by which spinal segment?

  1. T10 Correct answer.
  2. T6
  3. T4
  4. L1

Explanation

The umbilicus is the landmark for the T10 dermatome, reflecting the level at which the anterior rami of T10 supply the periumbilical skin. T4 is at the nipples and L1 at the groin.

Question 45Anatomy

Which muscle of the rotator cuff is primarily responsible for initiating abduction of the arm in the first 15 degrees?

  1. Deltoid
  2. Infraspinatus
  3. Teres minor
  4. Supraspinatus Correct answer.

Explanation

Supraspinatus initiates the first 15 degrees of abduction before the deltoid becomes the dominant abductor. Infraspinatus and teres minor are external rotators.

Question 46Anatomy

The femoral nerve is derived from which lumbar plexus roots?

  1. L2, L3, L4 Correct answer.
  2. S1, S2, S3
  3. L1, L2, L3
  4. L4, L5, S1

Explanation

The femoral nerve arises from the posterior divisions of the anterior rami of L2, L3 and L4. It supplies the anterior thigh compartment and the knee jerk reflex.

Question 47Anatomy

Which heart valve lies most anteriorly on a lateral chest radiograph?

  1. Tricuspid valve
  2. Aortic valve
  3. Pulmonary valve Correct answer.
  4. Mitral valve

Explanation

The pulmonary valve is the most anteriorly and superiorly placed valve, lying behind the sternum at the left third costal cartilage. The aortic valve is central and the mitral valve is most posterior.

Question 48Anatomy

The thoracic duct drains into which venous structure?

  1. Azygos vein in the posterior mediastinum
  2. Right brachiocephalic vein near its origin
  3. Left brachiocephalic vein at the junction with the internal jugular vein Correct answer.
  4. Superior vena cava directly

Explanation

The thoracic duct terminates at the left venous angle, where the left internal jugular and left subclavian veins join to form the left brachiocephalic vein. The right lymphatic duct drains at the corresponding right venous angle.

Question 49Anatomy

A patient sustains a fracture through the surgical neck of the humerus. Which nerve is most likely injured?

  1. Musculocutaneous nerve
  2. Axillary nerve Correct answer.
  3. Radial nerve
  4. Median nerve

Explanation

The axillary nerve winds around the surgical neck of the humerus with the posterior circumflex humeral artery, making it vulnerable in fractures at this site. It supplies the deltoid and teres minor.

Question 50Anatomy

Injury to the common fibular (peroneal) nerve at the neck of the fibula produces which deficit?

  1. Loss of knee extension with absent knee jerk
  2. Inability to plantarflex the foot with loss of sensation over the sole
  3. Loss of hip adduction with medial thigh numbness
  4. Inability to dorsiflex the foot with loss of sensation over the dorsum of the foot Correct answer.

Explanation

The common fibular nerve winds around the fibular neck and supplies the anterior and lateral leg compartments, so injury causes foot drop and sensory loss over the dorsum of the foot. Plantarflexion is preserved because it is mediated by the tibial nerve.