Chapter: Upper Limb Anatomy; Topic: Muscles of Hand; Subtopic: Lumbricals
Keyword Definitions:
• Lumbricals: Small intrinsic muscles of the hand arising from tendons of flexor digitorum profundus and inserting into extensor expansion.
• MCP Joints: Metacarpophalangeal joints, where the fingers meet the hand.
• IP Joints: Interphalangeal joints of the fingers, responsible for flexion and extension movements.
• Ulnar Nerve: Supplies intrinsic muscles of hand except the thenar and first two lumbricals.
• Median Nerve: Supplies first two lumbricals and most forearm flexors.
Lead Question - 2015
True about lumbricals is
a) Flex IP joints and extends MCP joint
b) 1st and 2nd supplied by radial nerve
c) 3 and 4 supplied by superficial branch of ulnar
d) Origin from tendons of flexor digitorum profundus
Explanation (Answer: d)
Lumbricals originate from tendons of flexor digitorum profundus and insert into the extensor expansion. They flex the metacarpophalangeal (MCP) joints and extend interphalangeal (IP) joints. The first and second lumbricals are supplied by the median nerve, while the third and fourth are supplied by the deep branch of the ulnar nerve.
1. Which nerve supplies the 3rd and 4th lumbricals?
a) Median nerve
b) Radial nerve
c) Ulnar nerve
d) Musculocutaneous nerve
Explanation (Answer: c)
The third and fourth lumbricals are supplied by the deep branch of the ulnar nerve. This branch originates in the palm after passing through Guyon’s canal. The ulnar nerve provides motor supply to most intrinsic hand muscles, contributing to finger flexion at MCP and extension at IP joints.
2. Which of the following actions best describes lumbrical function?
a) Flex MCP and extend IP joints
b) Extend MCP and flex IP joints
c) Flex both MCP and IP joints
d) Extend both MCP and IP joints
Explanation (Answer: a)
Lumbricals act simultaneously to flex the MCP joints and extend the IP joints by inserting into the extensor expansion. This unique dual function enables precise hand movements such as writing and typing. Their coordination is essential for normal finger dexterity and smooth control of digital motion.
3. Lumbricals arise from which tendon?
a) Flexor digitorum profundus
b) Flexor digitorum superficialis
c) Extensor digitorum
d) Palmaris longus
Explanation (Answer: a)
All four lumbricals arise from the tendons of flexor digitorum profundus. The first and second originate from the lateral two tendons (unipennate), while the third and fourth are bipennate. They pass dorsally around the fingers to insert into extensor expansions, enabling coordinated flexion and extension.
4. Which of the following lumbricals are unipennate?
a) 1st and 2nd
b) 3rd and 4th
c) All four
d) None
Explanation (Answer: a)
The first and second lumbricals are unipennate, originating from one tendon each of flexor digitorum profundus. The third and fourth are bipennate, arising from adjacent tendons. This structural difference correlates with their nerve supply: the median nerve innervates unipennate, and the ulnar nerve supplies bipennate lumbricals.
5. Which lumbrical receives dual nerve supply occasionally?
a) First
b) Second
c) Third
d) Fourth
Explanation (Answer: c)
In some individuals, the third lumbrical receives dual innervation from both median and ulnar nerves, a variation that ensures preserved hand function if one nerve is compromised. Such anatomical variations hold clinical significance during nerve injury assessments and reconstructive surgeries of the palm and fingers.
6. A patient with carpal tunnel syndrome shows weakness in which lumbricals?
a) 1st and 2nd
b) 3rd and 4th
c) All lumbricals
d) None
Explanation (Answer: a)
Carpal tunnel syndrome compresses the median nerve beneath the flexor retinaculum, affecting its motor branches to the first and second lumbricals. This results in weakened flexion at MCP and impaired extension at IP joints of the index and middle fingers, characteristic of median nerve palsy.
7. Injury to the ulnar nerve at the wrist will affect which lumbricals?
a) 1st and 2nd
b) 3rd and 4th
c) Only 4th
d) None
Explanation (Answer: b)
Ulnar nerve injury at the wrist affects the deep branch, leading to paralysis of the third and fourth lumbricals. This produces clawing of the ring and little fingers due to unopposed extensor and flexor activity, a key diagnostic feature in ulnar nerve palsy at the hand level.
8. Which statement about lumbrical muscle insertion is true?
a) Inserts into extensor expansion
b) Inserts into flexor retinaculum
c) Inserts into carpal bones
d) Inserts into flexor digitorum superficialis
Explanation (Answer: a)
Lumbricals insert into the lateral side of the extensor expansion of corresponding digits. This strategic insertion allows them to coordinate flexion at MCP and extension at IP joints, facilitating delicate movements such as gripping and writing. Their action is vital for balanced finger coordination and dexterity.
9. A patient with ulnar nerve injury presents with claw hand. Which lumbricals are affected?
a) 3rd and 4th
b) 1st and 2nd
c) All four
d) None
Explanation (Answer: a)
Claw hand results from paralysis of the 3rd and 4th lumbricals supplied by the ulnar nerve. The MCP joints are hyperextended, and IP joints are flexed due to loss of lumbrical action. Early physiotherapy helps restore balance between flexor and extensor forces, minimizing deformity progression.
10. Which of the following statements regarding lumbricals is false?
a) Flex MCP and extend IP joints
b) Supplied by both median and ulnar nerves
c) Originate from FDP tendons
d) Supplied by radial nerve
Explanation (Answer: d)
Lumbricals are not supplied by the radial nerve. The first two receive innervation from the median nerve, and the last two from the ulnar nerve. The radial nerve supplies only extensor muscles in the forearm, not intrinsic hand muscles. Thus, option (d) is false and incorrect.
Chapter: Upper Limb Anatomy; Topic: Cubital Fossa; Subtopic: Boundaries and Contents
Keyword Definitions:
• Cubital Fossa: A triangular depression on the anterior aspect of the elbow.
• Brachioradialis: A forearm muscle forming the lateral boundary of the cubital fossa.
• Pronator Teres: A forearm muscle forming the medial boundary of the cubital fossa.
• Brachialis: Lies deep to the biceps and forms the floor of the cubital fossa.
• Biceps Brachii: Lies superficially and forms part of the roof over the cubital fossa.
Lead Question - 2015
Lateral boundary of cubital fossa is formed by:
a) Brachioradialis
b) Pronator teres
c) Brachialis
d) Biceps
Explanation (Answer: a)
The lateral boundary of the cubital fossa is formed by the brachioradialis muscle, while the medial boundary is formed by pronator teres. The floor is formed by brachialis and supinator, and the roof by skin, fascia, and bicipital aponeurosis. It contains the median nerve, brachial artery, and tendon of biceps brachii.
1. The medial boundary of the cubital fossa is formed by:
a) Brachioradialis
b) Pronator teres
c) Biceps brachii
d) Brachialis
Explanation (Answer: b)
The pronator teres forms the medial boundary of the cubital fossa. It originates from the medial epicondyle of the humerus and coronoid process of the ulna. The muscle assists in pronation and flexion of the forearm. Its relationship with the fossa helps guide clinical venipuncture and nerve block procedures.
2. The cubital fossa contains all of the following except:
a) Median nerve
b) Radial nerve
c) Brachial artery
d) Ulnar nerve
Explanation (Answer: d)
The ulnar nerve does not pass through the cubital fossa. It runs posterior to the medial epicondyle, in the groove between it and the olecranon. The cubital fossa contains the median nerve, brachial artery (dividing into radial and ulnar arteries), biceps tendon, and radial nerve (laterally under brachioradialis).
3. The floor of the cubital fossa is formed by:
a) Pronator teres and brachioradialis
b) Brachialis and supinator
c) Biceps and brachialis
d) Flexor carpi radialis and supinator
Explanation (Answer: b)
The floor of the cubital fossa is formed medially by brachialis and laterally by supinator. Brachialis originates from the anterior surface of the humerus, while supinator wraps around the proximal radius. These muscles support the deeper neurovascular structures during elbow flexion and provide protection during venipuncture.
4. Roof of the cubital fossa includes:
a) Skin and fascia only
b) Skin, fascia, and bicipital aponeurosis
c) Fascia and brachialis
d) Skin and radial nerve
Explanation (Answer: b)
The roof of the cubital fossa comprises the skin, superficial fascia, deep fascia reinforced by the bicipital aponeurosis, and the median cubital vein crossing superficially. This structure is clinically important for intravenous injections and blood sampling. The aponeurosis protects the underlying brachial artery and median nerve from accidental injury.
5. Which structure passes most superficially in the cubital fossa?
a) Brachial artery
b) Median nerve
c) Median cubital vein
d) Biceps tendon
Explanation (Answer: c)
The median cubital vein passes superficially in the roof of the cubital fossa, making it the preferred site for venipuncture. It connects the cephalic and basilic veins. Beneath it lie the bicipital aponeurosis and deeper structures like the brachial artery and median nerve, protected during superficial procedures.
6. A patient presents with a supracondylar fracture of the humerus. Which cubital fossa structure is most at risk?
a) Brachial artery
b) Ulnar nerve
c) Radial nerve
d) Median cubital vein
Explanation (Answer: a)
The brachial artery is most at risk in supracondylar fractures of the humerus due to its deep location within the cubital fossa. Injury may lead to ischemic contracture of the forearm muscles (Volkmann’s ischemic contracture). Prompt vascular assessment is essential to prevent irreversible damage and functional impairment.
7. Which nerve divides into superficial and deep branches within the cubital fossa?
a) Median nerve
b) Ulnar nerve
c) Radial nerve
d) Musculocutaneous nerve
Explanation (Answer: c)
The radial nerve divides into superficial and deep branches at the level of the cubital fossa. The superficial branch continues distally under brachioradialis for sensory supply, while the deep branch (posterior interosseous nerve) pierces the supinator muscle to supply extensor muscles of the forearm.
8. Which of the following muscles does NOT form part of the cubital fossa boundary?
a) Brachialis
b) Brachioradialis
c) Pronator teres
d) Supinator
Explanation (Answer: d)
Supinator forms part of the floor, not the boundary, of the cubital fossa. The lateral boundary is formed by brachioradialis, the medial by pronator teres, the floor by brachialis and supinator, and the roof by bicipital aponeurosis and skin. Supinator’s role is mainly in forearm supination, not boundary formation.
9. During venipuncture in the cubital fossa, which structure lies deep to the median cubital vein and must be protected?
a) Brachial artery
b) Radial artery
c) Ulnar nerve
d) Cephalic vein
Explanation (Answer: a)
The brachial artery lies deep to the median cubital vein and bicipital aponeurosis in the cubital fossa. The aponeurosis acts as a protective layer, preventing accidental arterial puncture during venipuncture. Awareness of this relationship is essential for safe medical procedures and avoiding hematoma formation or vascular injury.
10. Which artery divides into radial and ulnar branches in the cubital fossa?
a) Axillary artery
b) Brachial artery
c) Subclavian artery
d) Deep brachial artery
Explanation (Answer: b)
The brachial artery divides into the radial and ulnar arteries at the level of the neck of the radius within the cubital fossa. This division marks the transition from arm to forearm circulation. Clinically, palpation of the brachial artery pulse in the fossa aids in assessing upper limb blood flow.
Chapter: Upper Limb Anatomy; Topic: Muscles of Arm; Subtopic: Actions and Nerve Supply
Keyword Definitions:
• Biceps Brachii: A two-headed muscle of the anterior arm that flexes the elbow and supinates the forearm.
• Supination: Outward rotation of the forearm so the palm faces upward.
• Brachialis: Primary flexor of the forearm located deep to biceps.
• Coracobrachialis: Flexes and adducts the arm at the shoulder joint.
• Triceps Brachii: Extensor muscle of the arm located on the posterior aspect.
Lead Question - 2015
Muscle of Arm with additional supinator action?
a) Brachialis
b) Biceps
c) Coracobrachialis
d) Triceps
Explanation (Answer: b)
The biceps brachii is the only arm muscle that acts as both a flexor and a supinator of the forearm. When the elbow is flexed, it provides strong supination by rotating the radius over the ulna. The brachialis is purely a flexor, coracobrachialis acts on the shoulder, and triceps is an extensor.
1. Which muscle is the primary flexor of the forearm?
a) Biceps brachii
b) Brachialis
c) Brachioradialis
d) Coracobrachialis
Explanation (Answer: b)
The brachialis is the main flexor of the forearm at the elbow joint. It acts in all positions of pronation and supination. It originates from the anterior humerus and inserts into the coronoid process and ulnar tuberosity. It’s supplied by the musculocutaneous nerve and contributes to powerful elbow flexion.
2. Which of the following muscles acts only on the shoulder joint?
a) Biceps brachii
b) Coracobrachialis
c) Brachialis
d) Triceps
Explanation (Answer: b)
The coracobrachialis acts solely on the shoulder joint. It flexes and adducts the arm. It originates from the coracoid process and inserts on the medial humerus. It assists in stabilizing the humeral head during arm movements and is supplied by the musculocutaneous nerve. It doesn’t cross the elbow joint.
3. The long head of biceps brachii arises from:
a) Coracoid process
b) Supraglenoid tubercle
c) Infraglenoid tubercle
d) Greater tubercle
Explanation (Answer: b)
The long head of biceps brachii originates from the supraglenoid tubercle of the scapula and runs through the intertubercular groove. This tendon stabilizes the shoulder joint and assists in arm abduction and flexion. The short head arises from the coracoid process, joining the long head to form the biceps muscle.
4. Which nerve supplies the biceps brachii?
a) Radial nerve
b) Musculocutaneous nerve
c) Axillary nerve
d) Median nerve
Explanation (Answer: b)
The musculocutaneous nerve (C5–C7) innervates the biceps brachii, brachialis, and coracobrachialis muscles. It pierces the coracobrachialis and descends between the biceps and brachialis. It continues as the lateral cutaneous nerve of the forearm, supplying skin sensation. Damage to this nerve leads to weakened elbow flexion and supination.
5. The main action of the triceps brachii is:
a) Flexion of the elbow
b) Extension of the elbow
c) Supination of the forearm
d) Pronation of the forearm
Explanation (Answer: b)
The triceps brachii is the chief extensor of the elbow joint. Its long head arises from the infraglenoid tubercle, while lateral and medial heads originate from the posterior humerus. It inserts on the olecranon process and is innervated by the radial nerve. It stabilizes the elbow during extension and pushing actions.
6. A 25-year-old male presents with difficulty in supinating his forearm. Which muscle is likely injured?
a) Pronator teres
b) Biceps brachii
c) Brachialis
d) Brachioradialis
Explanation (Answer: b)
Injury to the biceps brachii leads to weakness in both forearm flexion and supination, especially when the elbow is flexed. The biceps acts as a powerful supinator in this position. The pronator teres pronates, not supinates. Brachialis flexes the forearm but doesn’t participate in rotation.
7. The bicipital aponeurosis provides protection to which structure during venipuncture?
a) Median nerve
b) Brachial artery
c) Radial artery
d) Ulnar nerve
Explanation (Answer: b)
The bicipital aponeurosis lies over the brachial artery and median nerve in the cubital fossa. It protects these structures during venipuncture in the median cubital vein. This broad aponeurosis extends medially from the biceps tendon and blends with the forearm fascia, reinforcing the fossa’s roof and ensuring vascular safety.
8. A patient with musculocutaneous nerve injury will have difficulty performing:
a) Extension at the elbow
b) Flexion and supination of the forearm
c) Pronation of the forearm
d) Wrist extension
Explanation (Answer: b)
The musculocutaneous nerve supplies the anterior compartment of the arm (biceps, brachialis, coracobrachialis). Injury impairs forearm flexion and supination. The biceps loses its function as both a flexor and supinator. Triceps and wrist extensors remain unaffected as they are supplied by the radial nerve.
9. Which of the following best describes the function of the brachioradialis muscle?
a) Supinates the forearm
b) Flexes the elbow in mid-pronation
c) Extends the forearm
d) Pronates the forearm
Explanation (Answer: b)
The brachioradialis flexes the forearm most effectively when the forearm is in a mid-prone (neutral) position. It acts as a stabilizer during rapid flexion movements and is supplied by the radial nerve. It doesn’t participate in pronation or supination. Clinically, its reflex tests the C6 spinal segment.
10. A rupture of the long head of the biceps tendon results in:
a) Popeye deformity
b) Winged scapula
c) Claw hand
d) Drop wrist
Explanation (Answer: a)
A rupture of the long head of biceps brachii causes a bulge in the lower arm called the “Popeye deformity.” This occurs due to retraction of the muscle belly. It leads to weakness in flexion and supination. The condition is commonly seen in athletes and older adults with tendon degeneration.
Chapter: Upper Limb Anatomy; Topic: Nerve Supply of Hand; Subtopic: Innervation of Nail Bed
Keyword Definitions:
• Median Nerve: Supplies most flexor muscles of forearm and lateral hand including palmar surface and nail beds of thumb, index, and middle fingers.
• Radial Nerve: Supplies extensor compartment of forearm and dorsal surface of hand except nail beds of lateral three and a half fingers.
• Ulnar Nerve: Supplies intrinsic hand muscles and medial one and a half fingers including their nail beds.
• Nail Bed: The skin beneath the nail plate supplied by cutaneous branches of digital nerves.
Lead Question – 2015
The nerve supply of nail bed of index finger is ?
a) Superficial br of radial nerve
b) Deep br of radial nerve
c) Median nerve
d) Ulnar nerve
Explanation: The median nerve supplies the nail beds of the index, middle, and lateral half of the ring finger via its palmar digital branches. Although the radial nerve supplies the dorsum of these fingers, the nail beds are derived from palmar side sensory supply. Hence, the correct answer is c) Median nerve. (100 words)
1. A patient presents with loss of sensation over the tip of the index finger. The most likely affected nerve is:
a) Ulnar nerve
b) Median nerve
c) Radial nerve
d) Musculocutaneous nerve
Explanation: The median nerve provides sensory supply to the palmar surface and tips (nail beds) of the thumb, index, middle, and half of the ring finger. Loss of sensation over the index fingertip suggests median nerve injury, typically seen in carpal tunnel syndrome. Hence, the correct answer is b) Median nerve. (100 words)
2. The dorsal surface of the hand is mainly supplied by:
a) Median nerve
b) Ulnar nerve
c) Radial nerve
d) Axillary nerve
Explanation: The radial nerve supplies sensation to the dorsum of the hand, especially the lateral two-thirds and dorsal aspects of proximal phalanges, excluding the nail beds. The ulnar nerve supplies the medial one-third of the dorsum. Median nerve’s contribution is minimal dorsally. Therefore, the correct answer is c) Radial nerve. (100 words)
3. Which of the following nerves is compressed in carpal tunnel syndrome?
a) Ulnar nerve
b) Median nerve
c) Radial nerve
d) Musculocutaneous nerve
Explanation: Carpal tunnel syndrome involves compression of the median nerve beneath the flexor retinaculum at the wrist. Symptoms include tingling, pain, and numbness in the lateral three and a half fingers and weakness of thenar muscles. Hence, the correct answer is b) Median nerve. (100 words)
4. In a patient with ulnar nerve injury at the wrist, which sensory area is affected?
a) Palmar surface of thumb
b) Nail bed of middle finger
c) Medial one and half fingers
d) Dorsum of hand laterally
Explanation: The ulnar nerve supplies the skin of the medial one and half fingers and their nail beds. Injury causes sensory loss in these areas, especially over the little finger and medial half of the ring finger. Therefore, the correct answer is c) Medial one and half fingers. (100 words)
5. Clinical test for median nerve injury involves checking for loss of sensation in:
a) Tip of thumb
b) Dorsum of hand
c) Medial palm
d) Lateral forearm
Explanation: Loss of sensation at the tip of the thumb indicates median nerve impairment since its digital branches supply this area. The test is useful for assessing sensory loss in carpal tunnel syndrome or distal median neuropathy. Hence, the correct answer is a) Tip of thumb. (100 words)
6. (Clinical) A typist complains of tingling in the thumb, index, and middle fingers, worsening at night. The probable diagnosis is:
a) Ulnar nerve palsy
b) Radial nerve palsy
c) Carpal tunnel syndrome
d) Thoracic outlet syndrome
Explanation: The described symptoms are classic for carpal tunnel syndrome, due to compression of the median nerve at the wrist. Nocturnal paresthesia and hand weakness are key features. Treatment includes splinting or surgical decompression. The correct answer is c) Carpal tunnel syndrome. (100 words)
7. (Clinical) A cut over the medial wrist results in loss of sensation over the little finger nail bed. Which nerve is injured?
a) Median nerve
b) Ulnar nerve
c) Radial nerve
d) Musculocutaneous nerve
Explanation: The ulnar nerve supplies the little finger and medial half of ring finger including their nail beds through its digital branches. Injury near the wrist leads to sensory loss in these regions. Hence, the correct answer is b) Ulnar nerve. (100 words)
8. (Clinical) A patient after humeral shaft fracture cannot extend the wrist. Which nerve is injured?
a) Median nerve
b) Ulnar nerve
c) Radial nerve
d) Axillary nerve
Explanation: Wrist drop following humeral shaft fracture indicates radial nerve injury. This nerve supplies the extensor compartment of the forearm, and its loss leads to inability to extend the wrist and fingers. Hence, the correct answer is c) Radial nerve. (100 words)
9. (Clinical) Loss of flexion at the distal interphalangeal joint of the index finger is due to lesion of:
a) Median nerve
b) Ulnar nerve
c) Radial nerve
d) Axillary nerve
Explanation: The anterior interosseous branch of median nerve supplies flexor digitorum profundus for index and middle fingers. Injury causes inability to flex the distal interphalangeal joints of these fingers, producing a characteristic “pointing index.” The correct answer is a) Median nerve. (100 words)
10. (Clinical) A patient has loss of sensation on dorsum of hand except fingertips. Which nerve is affected?
a) Median nerve
b) Radial nerve
c) Ulnar nerve
d) Musculocutaneous nerve
Explanation: The superficial branch of the radial nerve provides sensation to most of the dorsal hand, except the fingertips (nail beds) which are supplied by palmar digital branches of median and ulnar nerves. Thus, loss of dorsal hand sensation with sparing of fingertips suggests radial nerve lesion. Correct answer: b) Radial nerve. (100 words)
Chapter: Upper Limb Anatomy; Topic: Arteries of Upper Limb;
Subtopic: Anatomical Snuffbox and its Contents
Keyword Definitions:
• Anatomical Snuffbox: A triangular depression on the dorsolateral aspect of the wrist seen when the thumb is extended.
• Radial Artery: Main arterial content of the snuffbox, providing blood to the hand and thumb.
• Cephalic Vein: Superficial vein lying over the anatomical snuffbox.
• Superficial Branch of Radial Nerve: Provides cutaneous sensation over the snuffbox region.
• Scaphoid & Trapezium: Carpal bones forming the floor of the anatomical snuffbox.
Lead Question – 2015
Content of anatomical snuffbox
a) Radial artery
b) Brachial artery
c) Ulnar artery
d) Interosseus artery
Explanation: The radial artery is the main content of the anatomical snuffbox. It passes obliquely through the snuffbox, lying superficial to the scaphoid and trapezium bones, and deep to the tendons of the extensor pollicis longus and brevis. It later contributes to the deep palmar arch. Therefore, the correct answer is a) Radial artery. (100 words)
1. Which structure forms the floor of the anatomical snuffbox?
a) Lunate
b) Trapezium and scaphoid
c) Pisiform
d) Capitate
Explanation: The scaphoid and trapezium bones form the floor of the anatomical snuffbox. These bones are covered by the radial artery as it passes deep to the extensor tendons. This relationship is clinically significant because scaphoid fractures may compromise radial artery flow. The correct answer is b) Trapezium and scaphoid. (100 words)
2. Which tendons form the lateral boundary of the anatomical snuffbox?
a) Extensor pollicis longus
b) Extensor pollicis brevis and abductor pollicis longus
c) Extensor carpi radialis longus
d) Extensor digitorum
Explanation: The lateral boundary of the anatomical snuffbox is formed by the tendons of the extensor pollicis brevis and abductor pollicis longus. The medial boundary is formed by the tendon of the extensor pollicis longus. These tendons define the snuffbox during thumb extension. The correct answer is b) Extensor pollicis brevis and abductor pollicis longus. (100 words)
3. Which vein crosses the roof of the anatomical snuffbox?
a) Basilic vein
b) Median cubital vein
c) Cephalic vein
d) Radial vein
Explanation: The cephalic vein runs superficially over the anatomical snuffbox before it continues proximally along the lateral border of the forearm and arm. This vein is often visible and palpable and is used for venipuncture in some cases. Hence, the correct answer is c) Cephalic vein. (100 words)
4. Which nerve provides cutaneous sensation over the anatomical snuffbox?
a) Ulnar nerve
b) Median nerve
c) Superficial branch of radial nerve
d) Deep branch of radial nerve
Explanation: The superficial branch of the radial nerve provides sensory innervation over the skin covering the anatomical snuffbox. This branch emerges between the brachioradialis and extensor carpi radialis longus tendons. Injury to this nerve leads to loss of sensation over the dorsal aspect of the thumb. Correct answer: c) Superficial branch of radial nerve. (100 words)
5. Fracture of which bone endangers the blood supply in the anatomical snuffbox?
a) Lunate
b) Scaphoid
c) Pisiform
d) Capitate
Explanation: The scaphoid lies in the floor of the anatomical snuffbox and receives its blood supply mainly from branches of the radial artery. A fracture through the waist of the scaphoid can disrupt this supply, leading to avascular necrosis of its proximal fragment. Correct answer: b) Scaphoid. (100 words)
6. (Clinical) A patient presents with tenderness in the anatomical snuffbox following a fall on the outstretched hand. Which injury is most likely?
a) Scaphoid fracture
b) Lunate dislocation
c) Distal radius fracture
d) Trapezoid fracture
Explanation: Tenderness in the anatomical snuffbox is a key clinical sign of a scaphoid fracture. This occurs due to a fall on the outstretched hand. Since the radial artery passes through this area, vascular compromise and avascular necrosis can occur if untreated. Correct answer: a) Scaphoid fracture. (100 words)
7. (Clinical) A deep laceration in the anatomical snuffbox may injure which artery?
a) Ulnar artery
b) Radial artery
c) Posterior interosseous artery
d) Deep brachial artery
Explanation: The radial artery passes superficially through the anatomical snuffbox. A deep cut in this region may damage it, leading to bleeding and possible ischemia to structures supplied by the radial artery, including the thumb and lateral index finger. Correct answer: b) Radial artery. (100 words)
8. (Clinical) A patient has loss of sensation over the dorsum of the thumb and lateral hand without motor loss. Which nerve is involved?
a) Superficial radial nerve
b) Deep radial nerve
c) Median nerve
d) Ulnar nerve
Explanation: The superficial branch of the radial nerve supplies sensation to the dorsum of the thumb and lateral hand. It is purely sensory and can be injured due to wrist lacerations or tight wristbands. The absence of motor loss differentiates it from deep branch injury. Correct answer: a) Superficial radial nerve. (100 words)
9. (Clinical) In the event of a radial artery injury within the snuffbox, which structure remains safe?
a) Superficial branch of radial nerve
b) Scaphoid bone
c) Extensor pollicis longus tendon
d) Trapezium
Explanation: The superficial branch of the radial nerve lies superficial to the anatomical snuffbox, while the radial artery runs deep. Hence, in a deep arterial injury, the superficial branch of the radial nerve usually remains unaffected. Correct answer: a) Superficial branch of radial nerve. (100 words)
10. (Clinical) During catheterization through the radial artery, care is taken to avoid injury near the snuffbox because:
a) It lies over the brachial artery
b) It is superficial and close to bone
c) It has no accompanying veins
d) It is deeply placed under the flexors
Explanation: In the anatomical snuffbox, the radial artery is superficial and closely related to the scaphoid and trapezium bones, making it prone to injury or thrombosis during catheterization or cannulation. Therefore, careful technique is required to avoid complications. Correct answer: b) It is superficial and close to bone. (100 words)
Chapter: Upper Limb Anatomy; Topic: Extensor Compartments of Wrist; Subtopic: Third Extensor Compartment
Keyword Definitions:
Extensor Compartments: Six fibro-osseous tunnels on the dorsum of the wrist through which tendons of the extensor muscles pass.
EPL (Extensor Pollicis Longus): A muscle of the posterior forearm that extends the thumb and passes through the third extensor compartment.
Radial Styloid Process: A bony prominence of the distal radius that serves as an anatomical landmark near the tendons of the extensor muscles.
Synovial Sheath: A membrane enclosing a tendon, reducing friction during movement.
Lead Question (2015):
3rd extensor compartment of wrist contains tendon of?
a) ECRL
b) ECRB
c) EPL
d) EPB
Explanation: The third extensor compartment of the wrist contains the tendon of the Extensor Pollicis Longus (EPL). It passes around the dorsal tubercle of the radius (Lister’s tubercle) and extends to the distal phalanx of the thumb. This arrangement allows thumb extension at interphalangeal and metacarpophalangeal joints. Clinical significance includes tenosynovitis and intersection syndromes.
Guessed Questions:
1. Which of the following tendons passes through the first extensor compartment?
a) APL and EPB
b) ECRL and ECRB
c) EPL and EIP
d) ECU and EDM
Explanation: The first extensor compartment contains Abductor Pollicis Longus (APL) and Extensor Pollicis Brevis (EPB) tendons. It lies lateral to the radial styloid process. Inflammation of this compartment leads to De Quervain’s tenosynovitis, which causes pain during thumb movement and wrist deviation.
2. The sixth extensor compartment of wrist transmits which tendon?
a) ECU
b) ECRB
c) APL
d) EPL
Explanation: The Extensor Carpi Ulnaris (ECU) tendon passes through the sixth extensor compartment, located on the dorsal aspect of the ulna. It helps in wrist extension and ulnar deviation. Inflammation of this compartment is seen in rheumatoid arthritis or repetitive stress injuries affecting wrist stability.
3. The fourth extensor compartment contains which tendons?
a) EDC and EIP
b) EPL and EPB
c) APL and ECRL
d) ECU and EDM
Explanation: The fourth extensor compartment transmits Extensor Digitorum Communis (EDC) and Extensor Indicis Proprius (EIP) tendons. These pass beneath the extensor retinaculum and extend the fingers. Compression here can lead to dorsal wrist pain and impaired finger extension, commonly seen in repetitive strain conditions.
4. Which structure forms the roof of all extensor compartments at the wrist?
a) Extensor retinaculum
b) Palmar aponeurosis
c) Flexor retinaculum
d) Deep fascia of forearm
Explanation: The Extensor retinaculum forms the fibrous roof of all extensor compartments on the dorsum of the wrist. It prevents bowstringing of the extensor tendons during wrist movement. This thickened fascia attaches to the radius laterally and the ulna and triquetral bone medially.
5. The second extensor compartment transmits which tendons?
a) ECRL and ECRB
b) EPL and EPB
c) EIP and EDC
d) ECU and EDM
Explanation: The second compartment transmits Extensor Carpi Radialis Longus (ECRL) and Extensor Carpi Radialis Brevis (ECRB) tendons. These extend and abduct the wrist. They pass beneath the extensor retinaculum and are separated from the first compartment by a fibrous septum. Overuse may lead to lateral wrist pain.
6. (Clinical) A patient presents with pain over the radial styloid process on thumb movement. Which condition is likely?
a) De Quervain’s tenosynovitis
b) Carpal tunnel syndrome
c) Trigger finger
d) Tennis elbow
Explanation: The correct answer is De Quervain’s tenosynovitis. It involves inflammation of the synovial sheaths of APL and EPB tendons within the first extensor compartment. Pain worsens with thumb abduction or Finkelstein’s test. Repetitive strain and overuse are common causes in typists and new mothers.
7. (Clinical) A fracture of the distal radius causing rupture of the tendon in the third extensor compartment will affect which movement?
a) Thumb extension
b) Wrist flexion
c) Finger abduction
d) Thumb opposition
Explanation: The Extensor Pollicis Longus (EPL) tendon passes in the third compartment and may rupture after distal radius fractures. This leads to loss of thumb extension at the interphalangeal joint. Clinically, patients cannot lift the thumb off the table when the hand is flat.
8. (Clinical) A swelling on the dorsum of the wrist along the course of the fourth extensor compartment is most likely due to?
a) Ganglion cyst
b) Lipoma
c) Synovial sarcoma
d) Abscess
Explanation: A Ganglion cyst commonly arises from the synovial sheath of the tendons within the fourth extensor compartment. It presents as a painless swelling that may become tender on movement. Aspiration or surgical excision may be required if it interferes with wrist function.
9. (Clinical) A surgeon must avoid which structure while releasing the extensor retinaculum near the thumb?
a) Radial artery
b) Median nerve
c) Ulnar artery
d) Superficial branch of ulnar nerve
Explanation: The Radial artery lies close to the tendons of the first and second extensor compartments near the radial styloid process. During surgery for De Quervain’s tenosynovitis or wrist ganglion, care is taken to avoid injuring this artery to prevent ischemic complications or hematoma formation.
10. (Clinical) Pain during thumb extension after a distal radius fracture suggests injury to which tendon?
a) Extensor Pollicis Longus
b) Extensor Digitorum Communis
c) Flexor Pollicis Longus
d) Abductor Pollicis Longus
Explanation: Post-fracture irritation or rupture of the Extensor Pollicis Longus (EPL) tendon is common due to its close relation to Lister’s tubercle. The patient loses active thumb extension. Early recognition and tendon transfer procedures help restore functional movement and prevent disability.
Chapter: Lower Limb Anatomy; Topic: Gluteal Region; Subtopic: Structures Leaving the Pelvis through the Greater Sciatic Foramen
Keyword Definitions:
Pelvis: The bony basin formed by the hip bones, sacrum, and coccyx, supporting the spinal column and protecting pelvic organs.
Greater Sciatic Foramen: An opening in the posterior pelvis that allows nerves and vessels to pass from the pelvis to the gluteal region.
Piriformis Muscle: A flat muscle originating from the sacrum and exiting through the greater sciatic foramen to insert into the greater trochanter of the femur.
Gluteal Vessels and Nerves: Branches of the internal iliac artery and sacral plexus that exit through the greater sciatic foramen to supply the gluteal region.
Lead Question (2015):
Which leaves the pelvis?
a) Piriformis
b) Sciatic nerve
c) Superior gluteal vessel
d) Inferior gluteal vessel
Explanation: The Piriformis muscle leaves the pelvis through the greater sciatic foramen. It divides the foramen into a suprapiriform and an infrapiriform compartment. The superior gluteal vessels and nerve exit above the muscle, while the inferior gluteal vessels, sciatic nerve, and pudendal structures pass below it. Piriformis acts as a landmark for gluteal neurovascular structures and laterally rotates the thigh.
Guessed Questions:
1. Which nerve emerges below the piriformis muscle?
a) Sciatic nerve
b) Superior gluteal nerve
c) Pudendal nerve
d) Obturator nerve
Explanation: The Sciatic nerve emerges below the piriformis muscle through the infrapiriform compartment of the greater sciatic foramen. It is the largest nerve in the body, supplying the posterior thigh and the entire lower limb below the knee. Compression by the piriformis may cause piriformis syndrome, leading to radiating pain.
2. Which structure passes above the piriformis muscle?
a) Superior gluteal vessels and nerve
b) Inferior gluteal vessels
c) Sciatic nerve
d) Posterior femoral cutaneous nerve
Explanation: The Superior gluteal artery, vein, and nerve pass above the piriformis muscle through the suprapiriform compartment. They supply the gluteus medius, minimus, and tensor fasciae latae muscles. These structures are vital for hip stabilization and abduction, especially during gait and single-leg stance activities.
3. Which muscle acts as a key landmark for identifying gluteal neurovascular structures?
a) Piriformis
b) Gluteus maximus
c) Obturator internus
d) Quadratus femoris
Explanation: The Piriformis muscle acts as a key landmark in the gluteal region. The superior gluteal vessels and nerves emerge above it, while the inferior gluteal, sciatic, and pudendal structures emerge below. Its orientation helps in safe intramuscular injection placement in the superolateral quadrant to avoid sciatic nerve injury.
4. (Clinical) Which nerve is most commonly injured during wrong site gluteal intramuscular injections?
a) Sciatic nerve
b) Femoral nerve
c) Pudendal nerve
d) Obturator nerve
Explanation: The Sciatic nerve is most frequently injured during improper gluteal injections placed in the inferomedial quadrant. Safe injection should be in the superolateral quadrant of the gluteal region. Injury causes weakness in knee flexion, foot drop, and sensory loss in the leg and foot, leading to functional disability.
5. The inferior gluteal artery is a branch of which vessel?
a) Internal iliac artery
b) External iliac artery
c) Femoral artery
d) Deep femoral artery
Explanation: The Inferior gluteal artery is a terminal branch of the internal iliac artery. It exits through the infrapiriform compartment below the piriformis muscle, accompanying the inferior gluteal nerve and vein. It supplies gluteus maximus and posterior thigh muscles. It also anastomoses with branches of the medial circumflex femoral artery.
6. (Clinical) A patient presents with buttock pain radiating down the leg after sitting long hours. Which structure is likely compressed?
a) Sciatic nerve
b) Femoral nerve
c) Tibial nerve
d) Obturator nerve
Explanation: The Sciatic nerve can be compressed by the piriformis muscle leading to piriformis syndrome. This causes radiating pain similar to sciatica but without spinal pathology. Stretching, posture correction, and muscle relaxation are effective treatments. Severe cases may need surgical decompression of the piriformis tunnel.
7. (Clinical) During posterior hip dislocation, which nerve is most commonly injured?
a) Sciatic nerve
b) Obturator nerve
c) Femoral nerve
d) Pudendal nerve
Explanation: The Sciatic nerve lies posterior to the hip joint and is vulnerable to injury in posterior hip dislocations. Symptoms include weakness of hamstrings and all muscles below the knee, with sensory loss over the leg and foot. Early reduction and physiotherapy are essential to prevent chronic neuropathic pain and gait impairment.
8. The pudendal nerve leaves the pelvis through which route?
a) Greater sciatic foramen below piriformis
b) Lesser sciatic foramen
c) Obturator canal
d) Femoral canal
Explanation: The Pudendal nerve leaves the pelvis through the greater sciatic foramen below the piriformis, winds around the ischial spine, and enters the perineum via the lesser sciatic foramen. It supplies the perineal muscles and external anal sphincter. Damage leads to perineal numbness and incontinence.
9. (Clinical) A gluteal abscess spreading into the pelvis may pass through which structure?
a) Greater sciatic foramen
b) Lesser sciatic foramen
c) Obturator canal
d) Sacral hiatus
Explanation: The Greater sciatic foramen acts as a potential pathway for infection spread between the gluteal region and pelvis. Abscesses involving piriformis or pelvic structures may track through this foramen. Clinical symptoms include deep buttock pain, fever, and difficulty in sitting or walking due to inflammation.
10. (Clinical) After pelvic surgery, a patient shows loss of hip abduction and pelvic drop on walking. Which nerve is injured?
a) Superior gluteal nerve
b) Inferior gluteal nerve
c) Sciatic nerve
d) Pudendal nerve
Explanation: The Superior gluteal nerve supplies gluteus medius, minimus, and tensor fasciae latae muscles. Injury leads to Trendelenburg gait due to pelvic drop on the contralateral side during walking. It may occur from pelvic fractures, injections near the piriformis, or iatrogenic injury during gluteal surgery.
Chapter: Lower Limb Anatomy; Topic: Foot Joints; Subtopic: Movements at Subtalar and Midtarsal Joints
Keyword Definitions:
Abduction of Foot: Movement of the forefoot away from the midline of the body, occurring mainly at the subtalar and midtarsal joints.
Adduction of Foot: Movement of the forefoot toward the midline of the body, also involving subtalar and transverse tarsal joints.
Subtalar Joint: The articulation between the talus and calcaneus bones, permitting inversion, eversion, abduction, and adduction movements.
Midtarsal (Transverse Tarsal) Joint: Formed by talonavicular and calcaneocuboid joints, it assists subtalar joint in complex foot movements.
Lead Question (2015):
Abduction and adduction of foot occurs at which joints?
a) Ankle
b) Subtalar
c) Tarso-metatarsal
d) None
Explanation: The Subtalar joint is responsible for abduction and adduction of the foot. These movements occur as part of the complex inversion and eversion actions of the foot. The subtalar joint between the talus and calcaneus permits the rotation of the foot around an oblique axis, essential for adaptation to uneven ground during gait and balance maintenance.
Guessed Questions:
1. Inversion and eversion of the foot primarily occur at which joint?
a) Subtalar joint
b) Ankle joint
c) Metatarsophalangeal joint
d) Intertarsal joint
Explanation: The Subtalar joint is primarily responsible for inversion and eversion of the foot. This joint allows the foot to adjust to irregular surfaces and contributes to shock absorption during walking. Inversion turns the sole medially, while eversion turns it laterally, maintaining stability and balance during locomotion.
2. Dorsiflexion and plantarflexion occur mainly at which joint?
a) Ankle joint
b) Subtalar joint
c) Tarso-metatarsal joint
d) Interphalangeal joint
Explanation: The Ankle joint (talocrural joint) allows dorsiflexion and plantarflexion of the foot. It is a hinge-type synovial joint formed between the distal tibia, fibula, and talus. Dorsiflexion raises the foot upwards, while plantarflexion points the toes downward, essential for walking, running, and jumping activities.
3. (Clinical) A patient with subtalar arthritis will have difficulty performing which movement?
a) Inversion and eversion
b) Dorsiflexion
c) Plantarflexion
d) Toe extension
Explanation: The Subtalar joint enables inversion and eversion of the foot. In subtalar arthritis, these movements become painful and restricted, making it difficult to walk on uneven surfaces. The joint’s oblique axis movement is compromised, leading to stiffness and imbalance in gait correction during locomotion.
4. The subtalar joint is formed between which bones?
a) Talus and calcaneus
b) Talus and navicular
c) Calcaneus and cuboid
d) Navicular and cuboid
Explanation: The Subtalar joint is formed between the inferior surface of the talus and the superior surface of the calcaneus. It is a synovial joint that allows complex rotatory movements, including inversion, eversion, abduction, and adduction. It provides adaptability and mobility to the foot during locomotion.
5. (Clinical) Which joint injury limits walking on uneven ground the most?
a) Subtalar joint
b) Ankle joint
c) Metatarsophalangeal joint
d) Knee joint
Explanation: Injury to the Subtalar joint significantly limits the ability to walk on uneven surfaces because inversion and eversion occur here. These movements adjust the foot position during gait. Loss of subtalar movement results in rigid foot mechanics, poor shock absorption, and instability during side-to-side movements.
6. The transverse tarsal joint includes which of the following?
a) Talonavicular and calcaneocuboid joints
b) Talocalcaneal and naviculocuboid joints
c) Ankle and talonavicular joints
d) Tarsometatarsal joints
Explanation: The Transverse tarsal joint consists of the talonavicular and calcaneocuboid joints. These joints together enhance the range of inversion and eversion. They help maintain foot flexibility and stability during walking, running, and balancing on uneven terrains. This joint acts with the subtalar joint for smooth foot movements.
7. (Clinical) Which joint is involved in clubfoot deformity correction?
a) Subtalar joint
b) Ankle joint
c) Tarso-metatarsal joint
d) Interphalangeal joint
Explanation: The Subtalar joint is primarily corrected during treatment of clubfoot (talipes equinovarus). In this congenital deformity, the foot is inverted and plantarflexed due to abnormal subtalar alignment. Gradual manipulation and casting (Ponseti method) help restore normal subtalar joint positioning for proper foot orientation and walking ability.
8. (Clinical) A fall from height causing inversion injury damages which joint first?
a) Subtalar joint
b) Ankle joint
c) Tarso-metatarsal joint
d) Interphalangeal joint
Explanation: Inversion injuries often affect the Subtalar joint due to the sudden medial rotation of the foot. The interosseous talocalcaneal ligament is frequently strained. Such injuries cause pain below the lateral malleolus, difficulty in eversion, and tenderness over the subtalar region, commonly misdiagnosed as ankle sprains.
9. Which ligament maintains stability of the subtalar joint?
a) Interosseous talocalcaneal ligament
b) Deltoid ligament
c) Plantar calcaneonavicular ligament
d) Long plantar ligament
Explanation: The Interosseous talocalcaneal ligament is the key stabilizer of the subtalar joint. It lies within the tarsal canal between the talus and calcaneus, preventing excessive inversion and eversion. Damage to this ligament can cause chronic subtalar instability and abnormal movement patterns during gait.
10. (Clinical) A fracture of the calcaneus most severely affects which joint?
a) Subtalar joint
b) Ankle joint
c) Tarso-metatarsal joint
d) Midtarsal joint
Explanation: The Subtalar joint is most affected in calcaneal fractures because it articulates with the superior talus. Fracture disruption leads to post-traumatic arthritis, restricted inversion-eversion, and chronic heel pain. CT imaging helps in diagnosis. Treatment may include surgical fixation to restore the subtalar articular surface alignment and movement.
Chapter: Gross Anatomy; Topic: Lower Limb; Subtopic: Femoral Triangle
Keyword Definitions:
• Femoral Triangle: A triangular space on the anterior aspect of the upper thigh bounded by the inguinal ligament, sartorius, and adductor longus.
• Sartorius: Longest muscle of the body forming the lateral boundary of the femoral triangle.
• Adductor Longus: Forms the medial boundary and part of the floor.
• Femoral Vessels: Major artery and vein supplying the lower limb.
• Inguinal Ligament: Upper boundary of the femoral triangle.
Lead Question – 2015
All are true about femoral triangle, EXCEPT?
a) Lateral margin is formed by sartorius
b) Floor is formed by adductor longus
c) Contains the femoral vessels
d) None of the above
Explanation: The femoral triangle is bounded laterally by the sartorius, medially by adductor longus, and superiorly by the inguinal ligament. Its floor is formed by iliopsoas and pectineus muscles, not adductor longus. It contains the femoral nerve, artery, and vein arranged laterally to medially. Answer: (b) Floor is formed by adductor longus.
1. Which of the following structures forms the medial boundary of the femoral triangle?
a) Sartorius
b) Adductor longus
c) Inguinal ligament
d) Rectus femoris
Explanation: The medial boundary of the femoral triangle is formed by the adductor longus muscle, while the lateral boundary is formed by sartorius. The inguinal ligament forms the base. Understanding these boundaries is essential in locating the femoral pulse during clinical examination. Answer: (b) Adductor longus.
2. Which structure lies most lateral in the femoral triangle?
a) Femoral nerve
b) Femoral artery
c) Femoral vein
d) Femoral canal
Explanation: In the femoral triangle, the arrangement from lateral to medial is “NAVEL” – Nerve, Artery, Vein, Empty space, and Lymphatics. The femoral nerve is therefore the most lateral structure. This arrangement helps in performing femoral nerve blocks. Answer: (a) Femoral nerve.
3. Which muscle forms the floor of the femoral triangle medially?
a) Iliacus
b) Pectineus
c) Adductor brevis
d) Sartorius
Explanation: The floor of the femoral triangle is formed by the iliopsoas laterally and pectineus medially. These muscles provide support to the femoral artery and vein that lie above them. The adductor longus contributes to the medial boundary, not the floor. Answer: (b) Pectineus.
4. The femoral sheath encloses all of the following EXCEPT:
a) Femoral artery
b) Femoral vein
c) Femoral nerve
d) Femoral canal
Explanation: The femoral sheath is a funnel-shaped fascial sleeve enclosing the femoral artery, femoral vein, and femoral canal but not the femoral nerve. This anatomical distinction is important in surgeries and hernia diagnosis. Answer: (c) Femoral nerve.
5. Which of the following best describes the clinical importance of the femoral triangle?
a) Site for venous sampling
b) Site for arterial catheterization
c) Both a and b
d) None
Explanation: The femoral triangle provides easy access to major vessels for procedures like arterial catheterization, femoral pulse palpation, and venous sampling. It is a key anatomical landmark for clinicians and surgeons due to its superficial vascular location. Answer: (c) Both a and b.
6. A 55-year-old male undergoing cardiac catheterization through the femoral artery—where should the puncture be made?
a) Below the inguinal ligament
b) Above the inguinal ligament
c) At mid-thigh
d) Near adductor canal
Explanation: The ideal puncture site for femoral artery access is just below the inguinal ligament within the femoral triangle. Puncturing above it risks retroperitoneal bleeding, while lower punctures may cause pseudoaneurysms. Answer: (a) Below the inguinal ligament.
7. A trauma patient with groin swelling after catheterization likely has damage to:
a) Femoral vein
b) Femoral nerve
c) Femoral artery
d) Deep femoral artery
Explanation: Groin swelling post-catheterization suggests hematoma from femoral artery injury. The artery’s superficial location in the femoral triangle makes it prone to iatrogenic damage. Ultrasound guidance helps prevent such complications. Answer: (c) Femoral artery.
8. Femoral hernia passes through which structure?
a) Femoral canal
b) Adductor canal
c) Obturator canal
d) Popliteal fossa
Explanation: A femoral hernia protrudes through the femoral canal, which is the medial compartment of the femoral sheath. It is more common in females due to a wider pelvis and can cause bowel strangulation if untreated. Answer: (a) Femoral canal.
9. In a femoral nerve block, the local anesthetic should be injected:
a) Lateral to femoral artery
b) Medial to femoral vein
c) Within the femoral sheath
d) Into adductor canal
Explanation: The femoral nerve lies lateral to the femoral artery and outside the femoral sheath. Therefore, local anesthetic is injected lateral to the artery to block the nerve effectively for lower limb surgeries. Answer: (a) Lateral to femoral artery.
10. The apex of the femoral triangle is formed by the meeting of:
a) Sartorius and adductor longus
b) Inguinal ligament and adductor longus
c) Sartorius and rectus femoris
d) Adductor longus and pectineus
Explanation: The apex of the femoral triangle is formed where sartorius crosses the adductor longus muscle. This apex continues as the adductor canal, transmitting vessels to the popliteal fossa. Answer: (a) Sartorius and adductor longus.
Chapter: Gross Anatomy; Topic: Lower Limb; Subtopic: Femoral Canal and Related Structures
Keyword Definitions:
• Femoral Canal: The medial compartment of the femoral sheath that allows expansion of the femoral vein and contains lymphatics.
• Genitofemoral Nerve: A nerve that arises from L1-L2 and divides into genital and femoral branches.
• Femoral Vein: A large vein that drains the lower limb and lies medial to the femoral artery.
• Lymph Node (of Cloquet): The deep inguinal lymph node within the femoral canal, receiving lymph from the deep structures of the limb.
Lead Question – 2015
Content of femoral canal:
a) Femoral branch of genitofemoral nerve
b) Genital branch of genitofemoral nerve
c) Femoral vein
d) Lymph node
Explanation: The femoral canal is the most medial compartment of the femoral sheath and contains the deep inguinal lymph node (Cloquet’s node), along with some areolar tissue and lymphatic vessels. It allows expansion of the femoral vein during increased venous return. Nerves are not found within the canal. Answer: (d) Lymph node.
1. The boundaries of the femoral canal include all of the following EXCEPT:
a) Femoral vein (laterally)
b) Lacunar ligament (medially)
c) Inguinal ligament (anteriorly)
d) Pectineus (posteriorly)
Explanation: The femoral canal is bounded laterally by the femoral vein, medially by the lacunar ligament, anteriorly by the inguinal ligament, and posteriorly by the pectineus and fascia. These boundaries are clinically relevant because a femoral hernia passes through this confined space. Answer: All are correct; no exception.
2. The primary function of the femoral canal is to:
a) Allow passage of femoral nerve
b) Permit expansion of the femoral vein
c) Transmit lymphatics only
d) Transmit deep artery of thigh
Explanation: The femoral canal’s key function is to allow expansion of the femoral vein during increased venous return, such as during muscular contraction. It also provides a space for the passage of lymphatics and connective tissue. Answer: (b) Permit expansion of the femoral vein.
3. Which structure passes through the femoral ring into the femoral canal during a hernia?
a) Omentum
b) Small intestine
c) Both a and b
d) Femoral nerve
Explanation: A femoral hernia occurs when abdominal contents, usually omentum or small intestine, protrude through the femoral ring into the femoral canal. It is more common in women due to a wider pelvis. Answer: (c) Both a and b.
4. Which of the following is true about the femoral ring?
a) It is the proximal opening of the femoral canal
b) It is closed by the femoral septum
c) It transmits lymphatics
d) All of the above
Explanation: The femoral ring is the superior opening of the femoral canal. It is closed by the femoral septum and transmits lymphatics and connective tissue. It is the site of potential femoral herniation. Answer: (d) All of the above.
5. A 45-year-old woman presents with a groin swelling below and lateral to the pubic tubercle. The most likely diagnosis is:
a) Inguinal hernia
b) Femoral hernia
c) Obturator hernia
d) Lipoma
Explanation: A femoral hernia appears below and lateral to the pubic tubercle, while an inguinal hernia lies above it. The anatomical position helps differentiate these hernias during clinical diagnosis. Answer: (b) Femoral hernia.
6. Which structure separates the femoral canal from the lacunar ligament?
a) Femoral vein
b) Femoral sheath
c) Femoral septum
d) Iliopsoas tendon
Explanation: The femoral septum is a thin layer of tissue that separates the femoral canal from the lacunar ligament medially. It covers the femoral ring and provides structural support. Answer: (c) Femoral septum.
7. During femoral hernia surgery, which structure is at risk when enlarging the femoral ring?
a) Inferior epigastric artery
b) Obturator nerve
c) Aberrant obturator artery
d) Deep external pudendal artery
Explanation: The aberrant obturator artery may pass close to the femoral ring and can be injured during hernia repair. Damage to this artery can cause severe hemorrhage. Surgeons must identify this variation before incision. Answer: (c) Aberrant obturator artery.
8. A deep inguinal lymph node found within the femoral canal is called:
a) Cloquet’s node
b) Virchow’s node
c) Delphian node
d) Rouvière’s node
Explanation: Cloquet’s node, the deep inguinal lymph node, is located in the femoral canal and receives lymph from deep structures of the lower limb and glans penis/clitoris. It serves as a sentinel node for pelvic metastasis. Answer: (a) Cloquet’s node.
9. Which structure lies lateral to the femoral canal?
a) Femoral artery
b) Femoral vein
c) Femoral nerve
d) Deep femoral artery
Explanation: The femoral vein lies lateral to the femoral canal and medial to the femoral artery. This relationship helps in vascular access and identifying femoral canal boundaries during surgical procedures. Answer: (b) Femoral vein.
10. A patient presents with a painful lump below the inguinal ligament after lifting weights. Imaging shows bowel loops in the femoral canal. What is the best treatment?
a) Hernia truss application
b) Surgical repair of femoral ring
c) Manual reduction
d) Observation only
Explanation: Femoral hernias are prone to strangulation due to the narrow femoral ring. Surgical repair by widening or closing the femoral ring is the definitive treatment. Trusses and observation are not recommended. Answer: (b) Surgical repair of femoral ring.