Menu

Nerve & Tendon MCQs

Practice Set 25 of 53

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

Question 481

Topic: Nerve & Tendon

During an ulnar nerve transposition, the surgeon must release Osborne's ligament. This structure spans between the medial epicondyle and which other bony landmark?

. Coronoid process
. Olecranon
. Radial head
. Medial supracondylar ridge
. Trochlea

Correct Answer & Explanation

. Coronoid process

Explanation

Osborne's ligament forms the roof of the cubital tunnel, extending from the medial epicondyle to the olecranon process over the ulnar nerve.

Question 482

Topic: Nerve & Tendon

A patient presents with the inability to cross their index and middle fingers. Which muscle group and nerve combination is primarily responsible for this specific action?

. Palmar interossei, Deep branch of the ulnar nerve
. Dorsal interossei, Deep branch of the ulnar nerve
. Lumbricals, Median nerve
. Palmar interossei, Superficial branch of the ulnar nerve
. Dorsal interossei, Median nerve

Correct Answer & Explanation

. Palmar interossei, Deep branch of the ulnar nerve

Explanation

Crossing the fingers requires adduction, which is performed by the palmar interossei muscles (PAD). These muscles are innervated by the deep branch of the ulnar nerve.

Question 483

Topic: Nerve & Tendon

A runner complains of chronic medial heel and arch pain. Examination reveals a positive Tinel's sign posterior to the medial malleolus radiating to the plantar medial foot. Which muscle is innervated by the medial plantar nerve?

. Abductor hallucis
. Abductor digiti minimi
. Flexor digiti minimi brevis
. Adductor hallucis
. Quadratus plantae

Correct Answer & Explanation

. Abductor hallucis

Explanation

The medial plantar nerve innervates the abductor hallucis, flexor hallucis brevis, flexor digitorum brevis, and the first lumbrical. The other listed muscles are innervated by the lateral plantar nerve.

Question 484

Topic: Nerve & Tendon

A 6-year-old boy sustains a posterolateral displaced supracondylar fracture of the humerus. Which neurovascular structures are at the highest risk of being tethered or injured by the proximal fracture fragment?

. Radial nerve and profunda brachii artery
. Median nerve and brachial artery
. Ulnar nerve and superior ulnar collateral artery
. Anterior interosseous nerve and radial artery
. Musculocutaneous nerve and brachial artery

Correct Answer & Explanation

. Radial nerve and profunda brachii artery

Explanation

In a posterolateral displaced supracondylar humerus fracture, the proximal fragment displaces anteromedially. This places the brachial artery and the median nerve at greatest risk of direct injury or tethering.

Question 485

Topic: Nerve & Tendon

A patient with De Quervain's tenosynovitis demonstrates a positive Finkelstein test. The involved tendons form the radial (anterior) border of the anatomical snuffbox. Which of the following tendons forms the ulnar (posterior) border of this space?

. Extensor pollicis brevis
. Abductor pollicis longus
. Extensor pollicis longus
. Extensor carpi radialis longus
. Extensor carpi radialis brevis

Correct Answer & Explanation

. Extensor pollicis brevis

Explanation

The anatomical snuffbox is bordered radially by the first extensor compartment tendons (APL and EPB) and ulnarly by the third extensor compartment tendon (EPL).

Question 486

Topic: Nerve & Tendon

When utilizing the volar (Henry) approach to the proximal radius, the surgeon enters the internervous plane between the brachioradialis and the pronator teres. Which nerves supply these two muscles, respectively?

. Radial nerve and Median nerve
. Median nerve and Ulnar nerve
. Musculocutaneous nerve and Median nerve
. Radial nerve and Ulnar nerve
. Median nerve and Musculocutaneous nerve

Correct Answer & Explanation

. Radial nerve and Median nerve

Explanation

The brachioradialis is innervated by the radial nerve, while the pronator teres is innervated by the median nerve. This provides a safe, true internervous plane for exposing the proximal radius.

Question 487

Topic: Nerve & Tendon

The lumbrical muscles of the hand are unique in that they both originate from and insert onto tendons. Which of the following correctly describes the innervation of the lumbrical muscle associated with the ring finger?

. Deep branch of the ulnar nerve
. Superficial branch of the ulnar nerve
. Anterior interosseous nerve
. Recurrent motor branch of the median nerve
. Posterior interosseous nerve

Correct Answer & Explanation

. Deep branch of the ulnar nerve

Explanation

The third and fourth lumbricals (ring and small fingers) are innervated by the deep branch of the ulnar nerve. The first and second lumbricals (index and middle fingers) are innervated by the median nerve.

Question 488

Topic: Nerve & Tendon

In the proximal forearm, the median nerve passes between the two heads of the pronator teres. Which of the following structures anatomically separates the median nerve from the ulnar artery at this level?

. Ulnar head of the pronator teres
. Humeral head of the pronator teres
. Flexor digitorum superficialis
. Bicipital aponeurosis
. Brachioradialis

Correct Answer & Explanation

. Ulnar head of the pronator teres

Explanation

The deep (ulnar) head of the pronator teres separates the median nerve from the underlying ulnar artery. The median nerve passes deep to the humeral head but superficial to the ulnar head.

Question 489

Topic: Nerve & Tendon

Which of the following describes the typical motor innervation of the lumbrical muscles of the hand?

. All four by the median nerve
. All four by the ulnar nerve
. Radial two by the ulnar nerve, ulnar two by the median nerve
. Radial two by the median nerve, ulnar two by the ulnar nerve
. Radial two by the radial nerve, ulnar two by the median nerve

Correct Answer & Explanation

. All four by the median nerve

Explanation

The first and second lumbricals are unipennate and innervated by the median nerve. The third and fourth lumbricals are bipennate and innervated by the deep branch of the ulnar nerve.

Question 490

Topic: Nerve & Tendon

Surgical decompression of the ulnar nerve at the elbow requires an understanding of the cubital tunnel boundaries. Which structure forms the true floor of the cubital tunnel?

. Anterior bundle of the medial collateral ligament (MCL)
. Posterior bundle of the medial collateral ligament (MCL)
. Annular ligament
. Brachialis muscle fascia
. Osborne's ligament

Correct Answer & Explanation

. Anterior bundle of the medial collateral ligament (MCL)

Explanation

The floor of the cubital tunnel is formed by the elbow joint capsule and the posterior bundle of the medial collateral ligament (MCL). Osborne's ligament and the FCU aponeurosis form the roof.

Question 491

Topic: Nerve & Tendon

During a surgical exploration for radial tunnel syndrome, the surgeon identifies the most common site of compression of the posterior interosseous nerve. This structure is a fibrous band at the proximal edge of which of the following muscles?

. Extensor carpi radialis brevis
. Brachioradialis
. Supinator
. Pronator teres
. Extensor digitorum communis

Correct Answer & Explanation

. Extensor carpi radialis brevis

Explanation

The Arcade of Frohse is a fibrous arch at the proximal edge of the superficial head of the supinator muscle. It is the most common anatomic site of compression for the posterior interosseous nerve (PIN).

Question 492

Topic: Nerve & Tendon

A deep laceration to the hypothenar eminence severs the deep branch of the ulnar nerve. Assuming isolated injury to this branch, which of the following intrinsic hand muscles would most likely retain normal function?

. Adductor pollicis
. Third dorsal interosseous
. Third lumbrical
. Fourth lumbrical
. Second lumbrical

Correct Answer & Explanation

. Adductor pollicis

Explanation

The first and second lumbricals are unipennate muscles innervated by the median nerve. The third and fourth lumbricals, along with the adductor pollicis and all interossei, are innervated by the deep branch of the ulnar nerve.

Question 493

Topic: Nerve & Tendon

During a trigger finger release, excessive division of the flexor sheath can lead to bowstringing of the flexor tendons. Which of the following pulleys is most critical to preserve to prevent this complication?

. A1 pulley
. A2 pulley
. A3 pulley
. C1 pulley
. C2 pulley

Correct Answer & Explanation

. A1 pulley

Explanation

The A2 and A4 pulleys are the major biomechanical restraints preventing bowstringing of the flexor tendons. While the A1 pulley is sectioned during a trigger finger release, the A2 pulley must be carefully protected.

Question 494

Topic: Nerve & Tendon

When performing an ulnar nerve transposition at the elbow, the surgeon must release all potential sites of compression. Which of the following represents the most proximal potential site of ulnar nerve compression?

. Arcade of Struthers
. Cubital tunnel retinaculum
. Fascia of the flexor carpi ulnaris
. Arcade of Frohse
. Ligament of Struthers

Correct Answer & Explanation

. Arcade of Struthers

Explanation

The Arcade of Struthers is a fascial band extending from the medial head of the triceps to the medial intermuscular septum, located approximately 8 cm proximal to the medial epicondyle. It is the most proximal site of potential ulnar nerve entrapment.

Question 495

Topic: Nerve & Tendon

During an anterior subcutaneous transposition of the ulnar nerve, the nerve is released from the cubital tunnel. What anatomical structure forms the roof of the cubital tunnel?

. Struthers ligament
. Lacertus fibrosus
. Arcade of Struthers
. Osborne's ligament
. Medial intermuscular septum

Correct Answer & Explanation

. Struthers ligament

Explanation

Osborne's ligament, or the cubital tunnel retinaculum, spans from the medial epicondyle to the olecranon, forming the roof of the cubital tunnel. The Arcade of Struthers is located more proximally.

Question 496

Topic: Nerve & Tendon

A 6-year-old boy presents with an established nonunion of a lateral humeral condyle fracture sustained 2 years ago.

He demonstrates a progressive cubitus valgus deformity. Which of the following neurologic complications is most strongly associated with this condition?

. Acute median nerve palsy
. Tardy ulnar nerve palsy
. Posterior interosseous nerve syndrome
. Axillary nerve dysfunction
. Radial nerve neurapraxia

Correct Answer & Explanation

. Acute median nerve palsy

Explanation

Nonunion of a lateral condyle fracture typically leads to a progressive cubitus valgus deformity. Over time, this valgus angulation stretches the ulnar nerve, leading to tardy (late) ulnar nerve palsy.

Question 497

Topic: Nerve & Tendon

A 6-year-old child sustains a displaced lateral condyle fracture of the humerus that is missed and not treated operatively. If this progresses to a nonunion, which of the following long-term complications is most likely to develop years later?

. Cubitus varus
. Tardy median nerve palsy
. Anterior interosseous nerve syndrome
. Tardy ulnar nerve palsy
. Radioulnar synostosis

Correct Answer & Explanation

. Cubitus varus

Explanation

Nonunion of a lateral condyle humerus fracture leads to progressive cubitus valgus deformity. This chronic valgus stretching of the ulnar nerve over time frequently results in a tardy ulnar nerve palsy.

Question 498

Topic: Nerve & Tendon
A 5-year-old boy sustains a fall and presents with elbow pain. Radiographs reveal a displaced (>2 mm) lateral condyle fracture of the humerus. If left untreated, what is the most likely long-term complication of this injury?
. Cubitus varus
. Cubitus valgus and tardy ulnar nerve palsy
. Volkmann's ischemic contracture
. Radiocapitellar synostosis
. Median nerve entrapment

Correct Answer & Explanation

. Cubitus valgus and tardy ulnar nerve palsy

Explanation

Displaced pediatric lateral condyle fractures have a high rate of nonunion if not surgically stabilized. A nonunion can lead to a progressive cubitus valgus deformity, which stretches the ulnar nerve and often results in tardy ulnar nerve palsy.

Question 499

Topic: Nerve & Tendon

A 6-year-old boy sustains a completely displaced, extension-type supracondylar fracture of the humerus. During the neurologic examination, he is unable to flex the interphalangeal joint of his thumb and the distal interphalangeal joint of his index finger. Which nerve is most likely injured?

. Median nerve main trunk
. Anterior interosseous nerve
. Posterior interosseous nerve
. Ulnar nerve
. Radial nerve

Correct Answer & Explanation

. Median nerve main trunk

Explanation

The anterior interosseous nerve (AIN), a motor branch of the median nerve, is the most commonly injured nerve in extension-type supracondylar humerus fractures. It innervates the flexor pollicis longus (FPL), the flexor digitorum profundus (FDP) to the index and middle fingers, and the pronator quadratus. Injury results in the inability to flex the IP joint of the thumb and the DIP joint of the index finger (the 'OK' sign). Radial nerve injuries are more common in posteromedial displacement, while ulnar nerve injuries are more common in flexion-type fractures or as an iatrogenic injury during medial pinning.

Question 500

Topic: Nerve & Tendon
A 4-year-old boy sustains a minimally displaced (<2 mm) lateral condyle fracture of the humerus that is treated in a long-arm cast. He is lost to follow-up and returns 15 years later. Radiographs demonstrate an established nonunion of the lateral condyle. Which of the following clinical findings is most likely to be present on physical examination?
. Cubitus varus and median nerve palsy
. Cubitus valgus and tardy ulnar nerve palsy
. Flexion contracture and radial nerve palsy
. Cubitus rectus and anterior interosseous nerve palsy
. Gunstock deformity and posterior interosseous nerve palsy

Correct Answer & Explanation

. Cubitus valgus and tardy ulnar nerve palsy

Explanation

Lateral condyle fractures of the humerus have a high propensity for nonunion if not perfectly immobilized or surgically fixed when displaced, because fracture fluid bathes the site and muscle pull from the extensor origin prevents apposition. An established nonunion of the lateral condyle typically leads to progressive cubitus valgus due to the continued growth of the intact medial physis while the lateral side is deficient. This progressive valgus deformity stretches the ulnar nerve behind the medial epicondyle, classically resulting in a tardy ulnar nerve palsy years or decades after the initial injury.

Test Yourself

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

On this Page