Menu

1. General Principles & Basic Science MCQs

Practice Set 267 of 789

This practice set contains high-yield board review questions covering key concepts in 1. General Principles & Basic Science. Each clinical scenario is designed to test your diagnostic and management skills relevant to this subspecialty.

Question 5321

Topic: 1. General Principles & Basic Science

A 22-year-old male presents with severe chest pain and shortness of breath after a rugby tackle. Radiographs and a CT scan reveal a posterior sternoclavicular joint dislocation. What is the most appropriate next step in management?

. Closed reduction in the ER under procedural sedation
. Immediate open reduction and internal fixation with Kirschner wires
. Closed reduction in the OR with cardiothoracic surgery available
. Observation and sling immobilization
. Resection of the medial clavicle

Correct Answer & Explanation

. Closed reduction in the OR with cardiothoracic surgery available

Explanation

Posterior SC dislocations can compress critical mediastinal structures. Closed reduction should be attempted in the operating room with cardiothoracic surgery backup due to the significant risk of catastrophic vascular injury.

Question 5322

Topic: Surgical Anatomy & Approaches

A 35-year-old male sustains a closed transverse fracture of the middle third of the humeral shaft. On examination, he has a weak wrist drop but normal triceps extension. He is treated with a functional brace. At 12 weeks, there is no clinical or EMG evidence of radial nerve recovery. What is the next best step?

. Continue bracing and re-evaluate at 6 months
. Refer for tendon transfers
. Surgical exploration of the radial nerve
. Ultrasound-guided nerve block
. Amputation

Correct Answer & Explanation

. Surgical exploration of the radial nerve

Explanation

Radial nerve palsy associated with a closed humeral shaft fracture is initially observed. However, if there is no clinical or EMG evidence of recovery by 3 to 4 months, surgical exploration of the nerve is indicated.

Question 5323

Topic: Surgical Anatomy & Approaches

During an anterolateral deltoid-splitting approach for minimally invasive plate osteosynthesis (MIPO) of a proximal humerus fracture, what is the generally accepted safe distance from the lateral tip of the acromion to avoid injury to the axillary nerve?

. 1 to 2 cm
. 3 to 4 cm
. 5 to 7 cm
. 8 to 10 cm
. 10 to 12 cm

Correct Answer & Explanation

. 5 to 7 cm

Explanation

The axillary nerve courses circumferentially from posterior to anterior approximately 5 to 7 cm distal to the lateral edge of the acromion. Extending the deltoid split beyond 5 cm places the nerve at significant risk of iatrogenic transection.

Question 5324

Topic: Surgical Anatomy & Approaches

A patient has a humeral shaft fracture and is scheduled to undergo open reduction and internal fixation with a plate. What surgical approach will provide the greatest amount of exposure?

. Modified posterior approach with elevation of the medial and lateral heads of the triceps
. Posterior triceps-splitting approach
. Posterior triceps-splitting approach with radial nerve mobilization
. Posteromedial approach
. Lateral approach with radial nerve mobilization

Correct Answer & Explanation

. Modified posterior approach with elevation of the medial and lateral heads of the triceps

Explanation

The modified posterior approach with elevation of the medial and lateral heads of the triceps can provide exposure of 94% of the humeral shaft. The traditional posterior triceps-splitting approach exposes 55% of the humeral shaft. DeFranco MJ, Lawton JN: Radial nerve injuries associated with humeral fractures. J Hand Surg Am 2006;31:655-663.

Question 5325

Topic: Surgical Anatomy & Approaches

A 60-year-old man presents with chronic shoulder pain and weakness. On examination, he is unable to actively externally rotate his arm while it is held in 90 degrees of abduction (positive Hornblower's sign). This clinical finding indicates a deficiency in a muscle innervated by which of the following nerves?

. Musculocutaneous nerve
. Suprascapular nerve
. Spinal accessory nerve
. Axillary nerve
. Radial nerve

Correct Answer & Explanation

. Axillary nerve

Explanation

A positive Hornblower's sign indicates advanced pathology or fatty infiltration of the teres minor. The teres minor is innervated by the axillary nerve.

Question 5326

Topic: 1. General Principles & Basic Science

A 19-year-old male presents to the emergency department with dyspnea, dysphagia, and severe pain after a rugby tackle. Exam reveals a depression at the medial end of the clavicle. What is the most important next step in management?

. Routine anteroposterior radiographs of the chest
. Closed reduction in the emergency department with procedural sedation
. CT scan of the chest and prompt reduction in the operating room with thoracic surgery standby
. Immediate open reduction and internal fixation with a hook plate
. Figure-of-eight brace and discharge home

Correct Answer & Explanation

. CT scan of the chest and prompt reduction in the operating room with thoracic surgery standby

Explanation

Posterior sternoclavicular dislocations are orthopedic emergencies due to the high risk of compression or injury to the trachea, esophagus, and great vessels. A CT scan confirms the diagnosis and reduction must be performed in the OR with a thoracic surgeon available.

Question 5327

Topic: Surgical Anatomy & Approaches

When utilizing the volar approach to the distal radius (Modified Henry approach) for internal fixation of a volar Barton's fracture, the surgical interval is developed between which two anatomical structures?

. Flexor carpi radialis (FCR) and flexor pollicis longus (FPL)
. Flexor carpi radialis (FCR) and the radial artery
. Brachioradialis and the radial artery
. Flexor carpi ulnaris (FCU) and the ulnar nerve
. Palmaris longus and flexor carpi radialis (FCR)

Correct Answer & Explanation

. Flexor carpi radialis (FCR) and the radial artery

Explanation

The modified Henry approach utilizes the internervous plane between the median nerve (FCR) and radial nerve (brachioradialis). Specifically, the interval is developed between the FCR tendon (retracted ulnarly) and the radial artery (retracted radially).

Question 5328

Topic: Surgical Anatomy & Approaches

A 25-year-old male sustains an acute anterior shoulder dislocation. Post-reduction, you suspect an axillary nerve injury. What area should be evaluated to assess the sensory distribution of the axillary nerve?

. Medial aspect of the forearm
. Lateral aspect of the forearm
. Lateral aspect of the shoulder
. Medial aspect of the arm
. Dorsal first web space of the hand

Correct Answer & Explanation

. Lateral aspect of the shoulder

Explanation

The axillary nerve provides sensation to the lateral aspect of the shoulder via the superior lateral brachial cutaneous nerve. It is the most commonly injured nerve in anterior shoulder dislocations.

Question 5329

Topic: 1. General Principles & Basic Science

A 20-year-old male presents after a tackle in American football with acute shortness of breath and a palpable void at the medial end of his right clavicle. A CT scan confirms a posterior sternoclavicular dislocation. What is the most appropriate initial management step?

. Immediate open reduction in the operating room with cardiothoracic surgery standby
. Closed reduction in the emergency department using an anteriorly directed force
. Sling immobilization and outpatient follow-up
. Figure-of-eight brace application
. Closed reduction in the operating room with cardiothoracic surgery standby

Correct Answer & Explanation

. Closed reduction in the operating room with cardiothoracic surgery standby

Explanation

Posterior sternoclavicular dislocations are orthopedic emergencies due to potential mediastinal compression. The initial treatment is an attempted closed reduction in the operating room under general anesthesia, with a cardiothoracic surgeon available in case of vascular injury.

Question 5330

Topic: 1. General Principles & Basic Science

During an anatomic coracoclavicular (CC) ligament reconstruction for a chronic AC joint separation, the surgeon must replicate the native anatomy. Which statement correctly describes the anatomic insertion of the CC ligaments on the clavicle?

. The conoid inserts anterolaterally and the trapezoid posteromedially
. The conoid inserts posteromedially and the trapezoid anterolaterally
. Both insert on the anterior border of the distal clavicle
. The trapezoid is the primary restraint to superior translation
. The conoid is the primary restraint to axial compression

Correct Answer & Explanation

. The conoid inserts posteromedially and the trapezoid anterolaterally

Explanation

The conoid ligament inserts posteromedially on the conoid tubercle of the clavicle, whereas the trapezoid inserts anterolaterally. The conoid is the primary restraint to superior translation, while the trapezoid primarily resists axial compression.

Question 5331

Topic: 1. General Principles & Basic Science

An 18-year-old male football player sustains a direct blow to his medial clavicle. He presents with severe chest pain, shortness of breath, and dysphagia. Examination shows a depression of the medial clavicle. What is the most appropriate next step in management?

. Immediate bedside closed reduction using a towel clip
. Anteroposterior (AP) and apical lordotic chest radiographs
. CT scan of the chest and sternoclavicular joints, followed by reduction in the OR with thoracic surgery backup
. Application of a figure-of-eight brace and observation
. Open reduction and internal fixation with a hook plate

Correct Answer & Explanation

. CT scan of the chest and sternoclavicular joints, followed by reduction in the OR with thoracic surgery backup

Explanation

Posterior sternoclavicular dislocations can compress the trachea, esophagus, and great vessels, presenting a life-threatening emergency. A CT scan is the diagnostic imaging modality of choice, and reduction should be performed in the operating room with cardiothoracic surgery backup due to the risk of catastrophic vascular injury.

Question 5332

Topic: 1. General Principles & Basic Science

A 19-year-old rugby player presents to the emergency department after a direct blow to the medial clavicle. He complains of severe pain, mild shortness of breath, and dysphagia. Examination reveals a palpable void at the sternoclavicular joint. What is the most appropriate initial management?

. Immediate bedside closed reduction with anterior traction
. Closed reduction in the operating room with cardiothoracic surgery available
. Figure-of-eight brace and immediate discharge
. Open reduction and plate fixation of the medial clavicle
. Observation and sling immobilization for 4 weeks

Correct Answer & Explanation

. Closed reduction in the operating room with cardiothoracic surgery available

Explanation

This patient has a posterior sternoclavicular dislocation, which poses a life-threatening risk to mediastinal structures. Due to the risk of lacerating the underlying great vessels during manipulation, reduction must be performed in the operating room with cardiothoracic surgery standby.

Question 5333

Topic: 1. General Principles & Basic Science

A 24-year-old competitive weightlifter feels a tearing sensation in his anterior axilla during the eccentric phase of a heavy bench press. He has weakness in internal rotation and adduction. Which anatomic portion of the affected muscle is most likely ruptured?

. Clavicular head of the pectoralis major
. Sternal head of the pectoralis major
. Pectoralis minor
. Coracobrachialis
. Short head of the biceps brachii

Correct Answer & Explanation

. Sternal head of the pectoralis major

Explanation

Pectoralis major ruptures almost exclusively occur during the eccentric (lengthening) phase of a bench press. The sternal head, which forms the posterior layer of the tendon and inserts most proximally on the humerus, is placed under the greatest tension and typically tears first.

Question 5334

Topic: Surgical Anatomy & Approaches

During a deltoid-splitting approach for proximal humerus fracture fixation, the surgeon must be careful to avoid the axillary nerve. At approximately what distance distal to the lateral edge of the acromion does the axillary nerve typically cross the deep surface of the deltoid?

. 1 cm
. 3 cm
. 5 cm
. 7 cm
. 9 cm

Correct Answer & Explanation

. 5 cm

Explanation

The axillary nerve courses roughly 5 cm (or about 2 inches) distal to the lateral border of the acromion. A deltoid split should safely remain superior to this landmark to avoid denervating the anterior deltoid.

Question 5335

Topic: 1. General Principles & Basic Science

A 19-year-old male is tackled during a football game and presents with severe chest pain, dyspnea, dysphagia, and diminished pulses in his left arm. A posterior sternoclavicular dislocation is suspected. What is the most appropriate next step in management after securing the airway?

. Immediate closed reduction in the emergency department without imaging
. CT scan of the chest with IV contrast
. MRI of the brachial plexus
. Open reduction via a median sternotomy
. Application of a figure-of-8 brace

Correct Answer & Explanation

. CT scan of the chest with IV contrast

Explanation

Posterior sternoclavicular dislocations can be life-threatening due to compression of great vessels, the trachea, and esophagus. A contrast-enhanced CT scan is essential to evaluate the mediastinal structures before attempting a reduction.

Question 5336

Topic: Surgical Anatomy & Approaches

A 35-year-old man sustains a distal third spiral fracture of the humerus. On examination, he is unable to extend his wrist or fingers. Which nerve is most commonly injured in this specific fracture pattern?

. Axillary nerve
. Ulnar nerve
. Median nerve
. Radial nerve
. Musculocutaneous nerve

Correct Answer & Explanation

. Radial nerve

Explanation

A Holstein-Lewis fracture is a spiral fracture of the distal third of the humeral shaft. It has a high association with radial nerve entrapment or injury as the nerve passes through the intermuscular septum.

Question 5337

Topic: 1. General Principles & Basic Science

A 19-year-old male presents with severe medial chest pain, dysphagia, and a choking sensation following a rugby tackle. CT scan confirms a posterior sternoclavicular dislocation. Which vascular structure is located immediately posterior to the sternoclavicular joint and is most at risk of injury?

. Subclavian artery
. Internal jugular vein
. Brachiocephalic vein
. Ascending aorta
. Superior vena cava

Correct Answer & Explanation

. Brachiocephalic vein

Explanation

The brachiocephalic (innominate) vein is located immediately posterior to the sternoclavicular joint, making it the most vulnerable vascular structure in a posterior sternoclavicular dislocation. The trachea and esophagus are also at risk, leading to symptoms like dysphagia or shortness of breath.

Question 5338

Topic: 1. General Principles & Basic Science

An 18-year-old male rugby player presents with a posterior sternoclavicular dislocation. His neurovascular status is intact, and he has no respiratory distress. What is the most appropriate next step in management?

. Discharge in a sling with close outpatient follow-up
. Closed reduction in the emergency department with procedural sedation
. Closed reduction in the operating room with thoracic surgery available
. Immediate open reduction and plate fixation
. Resection of the medial clavicle

Correct Answer & Explanation

. Closed reduction in the operating room with thoracic surgery available

Explanation

Posterior sternoclavicular dislocations carry a significant risk of injury to the great vessels and trachea. Closed reduction should be attempted in the operating room under general anesthesia with cardiothoracic surgery on standby.

Question 5339

Topic: 1. General Principles & Basic Science

When performing a Zone II flexor tendon repair, which of the following surgical techniques allows for the safest implementation of an early active motion rehabilitation protocol?

. 2-strand core suture with an epitendinous repair
. 4-strand or 6-strand core suture with an epitendinous repair
. Single grasping locking suture
. Isolated epitendinous repair
. FDS excision and FDP 2-strand repair

Correct Answer & Explanation

. 4-strand or 6-strand core suture with an epitendinous repair

Explanation

Multi-strand repairs (4- or 6-strand) increase the tensile strength of the repair, allowing it to withstand the forces of early active motion protocols. An epitendinous suture further increases strength and reduces gapping.

Question 5340

Topic: 1. General Principles & Basic Science

A 28-year-old carpenter sustains a Zone II flexor tendon laceration. During repair, the surgeon chooses a 4-strand core suture technique instead of a 2-strand technique. What is the primary biomechanical advantage of this choice?

. Decreased tendon gliding resistance
. Increased gap resistance and tensile strength
. Faster intrinsic healing rate of the tendon
. Elimination of the need for an epitendinous suture
. Prevention of vincula avulsion

Correct Answer & Explanation

. Increased gap resistance and tensile strength

Explanation

Increasing the number of core suture strands proportionally increases the tensile strength and gap resistance of the repair. This robust repair allows for early active motion protocols, which significantly improve clinical outcomes and decrease adhesions.

Test Yourself

Switch to an interactive, timed exam simulation to truly master this topic.

On this Page