Topic: Upper Limb Nerves
Subtopic: Median Nerve and Branches
Keyword Definitions:
Anterior interosseous nerve: A branch of the median nerve, supplying deep flexors of the forearm and pronator quadratus.
Median nerve: Formed by medial and lateral cords, supplies most forearm flexors and hand muscles.
Radial nerve: A major nerve of the posterior arm, supplying extensors of the forearm and hand.
Ulnar nerve: Supplies intrinsic hand muscles and some forearm flexors.
Axillary nerve: Supplies deltoid and teres minor muscles, and shoulder sensation.
Lead Question - 2014
Anterior interosseous nerve is a branch of?
a) Radial nerve
b) Median nerve
c) Ulnar nerve
d) Axillary nerve
Explanation: The anterior interosseous nerve arises from the median nerve just below the elbow. It supplies flexor pollicis longus, lateral half of flexor digitorum profundus, and pronator quadratus. It does not provide cutaneous innervation. Therefore, the correct answer is Median nerve, which gives this important motor branch.
Guessed Questions
1. The anterior interosseous nerve supplies all except?
a) Flexor pollicis longus
b) Pronator quadratus
c) Flexor digitorum superficialis
d) Flexor digitorum profundus (lateral half)
Explanation: The anterior interosseous nerve supplies FPL, pronator quadratus, and the lateral half of FDP. Flexor digitorum superficialis is supplied by the median nerve but not its anterior interosseous branch. Thus, the correct answer is Flexor digitorum superficialis.
2. A patient with anterior interosseous nerve injury is unable to?
a) Flex distal phalanx of thumb
b) Flex proximal phalanx of thumb
c) Extend wrist
d) Abduct thumb
Explanation: Anterior interosseous nerve injury causes weakness in flexor pollicis longus, leading to inability to flex the distal phalanx of the thumb. Proximal flexion is intact, wrist extension involves radial nerve, and thumb abduction involves radial/median nerves. Thus, the correct answer is Flex distal phalanx of thumb.
3. A clinical sign of anterior interosseous nerve palsy is?
a) Ape thumb deformity
b) Hand of benediction
c) Pinch sign
d) Claw hand
Explanation: In anterior interosseous nerve palsy, patients cannot form a tip-to-tip pinch between thumb and index finger due to loss of FPL and FDP function. Instead, they approximate pads of fingers. This is called the Pinch sign, characteristic of AIN injury.
4. The median nerve in the forearm gives rise to?
a) Anterior interosseous nerve
b) Posterior interosseous nerve
c) Musculocutaneous nerve
d) Lateral pectoral nerve
Explanation: The median nerve gives off the anterior interosseous nerve below the elbow. The posterior interosseous is a branch of the radial nerve, musculocutaneous comes from the lateral cord, and lateral pectoral is from the lateral cord. Correct answer is Anterior interosseous nerve.
5. A patient with deep forearm pain and weakness of pinch grip but no sensory loss most likely has -
a) Median nerve lesion
b) Ulnar nerve lesion
c) Anterior interosseous nerve lesion
d) Radial nerve lesion
Explanation: Anterior interosseous nerve is purely motor. Its lesion causes deep forearm pain, loss of pinch grip, but no cutaneous sensory loss. Median and ulnar nerve lesions include sensory changes, radial nerve causes wrist drop. Correct answer is Anterior interosseous nerve lesion.
6. Flexor digitorum profundus is supplied by -
a) Median nerve alone
b) Ulnar nerve alone
c) Median and ulnar nerves
d) Radial nerve
Explanation: Flexor digitorum profundus has dual innervation. Lateral half (index and middle fingers) by anterior interosseous nerve (median), medial half (ring and little fingers) by ulnar nerve. Hence, correct answer is Median and ulnar nerves.
7. The anterior interosseous nerve runs along which artery?
a) Radial artery
b) Anterior interosseous artery
c) Posterior interosseous artery
d) Ulnar artery
Explanation: The anterior interosseous nerve runs on the anterior surface of the interosseous membrane, accompanying the anterior interosseous artery, a branch of the ulnar artery. Correct answer is Anterior interosseous artery.
8. Injury to anterior interosseous nerve affects which movement?
a) Thumb extension
b) Index finger DIP flexion
c) Wrist flexion
d) Elbow extension
Explanation: The anterior interosseous nerve supplies the lateral half of FDP, flexing DIP of index and middle fingers. Injury impairs DIP flexion of index finger. Wrist flexion is preserved by FCR, thumb extension by radial nerve, elbow extension by radial nerve. Correct answer is Index finger DIP flexion.
9. The "OK sign" test is used to diagnose -
a) Ulnar nerve palsy
b) Radial nerve palsy
c) Anterior interosseous nerve palsy
d) Axillary nerve palsy
Explanation: In anterior interosseous nerve palsy, the patient cannot form a circle using thumb and index finger tips, producing a flat "OK sign." This is diagnostic of Anterior interosseous nerve palsy. Other nerve lesions present with different clinical signs.
10. A 40-year-old with forearm fracture develops inability to flex thumb IP and index DIP joints, but no sensory loss. Which nerve is injured?
a) Ulnar nerve
b) Anterior interosseous nerve
c) Radial nerve
d) Musculocutaneous nerve
Explanation: Loss of thumb IP and index DIP flexion with no sensory loss indicates anterior interosseous nerve injury, as it supplies FPL and FDP lateral half. Ulnar nerve causes sensory loss, radial nerve affects extensors, musculocutaneous supplies arm flexors. Correct answer is Anterior interosseous nerve.
Topic: Upper Limb Bones
Subtopic: Ulna and its Processes
Keyword Definitions:
Olecranon process: The prominent proximal projection of the ulna forming the point of the elbow and insertion site for triceps tendon.
Trochlear notch: A large articular depression on ulna formed by olecranon and coronoid processes, articulating with humeral trochlea.
Radial notch: Small depression on ulna’s lateral side for articulation with the head of radius.
Olecranon fossa: A depression on the posterior distal humerus accommodating olecranon during extension.
Coronoid fossa: Depression on anterior distal humerus receiving coronoid process during flexion.
Lead Question - 2014
Olecranon process of ulna helps in formation of?
a) Radial notch
b) Trochlear notch
c) Olecranon fossa
d) Coronoid fossa
Explanation: The olecranon process along with the coronoid process forms the trochlear notch of ulna, articulating with the trochlea of humerus. This articulation allows hinge-like flexion and extension at the elbow. Therefore, the correct answer is Trochlear notch, not radial notch or humeral fossae.
Guessed Questions
1. The olecranon process provides insertion for?
a) Biceps brachii
b) Brachialis
c) Triceps brachii
d) Anconeus
Explanation: The olecranon process forms the posterior projection of ulna and serves as the insertion site for the tendon of triceps brachii. This allows elbow extension. Biceps inserts on radial tuberosity, brachialis on coronoid process, and anconeus on olecranon lateral aspect. Correct answer is Triceps brachii.
2. Fracture of olecranon process mainly impairs?
a) Elbow flexion
b) Elbow extension
c) Supination
d) Pronation
Explanation: Since the olecranon process is the insertion of triceps brachii, its fracture impairs the power of elbow extension. Flexion, supination, and pronation involve different muscles. Thus, the correct answer is Elbow extension.
3. The coronoid process is located -
a) Proximal ulna anteriorly
b) Proximal ulna posteriorly
c) Distal ulna
d) Radial head
Explanation: The coronoid process is a triangular anterior projection at proximal ulna below the trochlear notch. It serves as attachment for brachialis and helps stabilize elbow joint. Thus, correct answer is Proximal ulna anteriorly.
4. The radial notch of ulna articulates with?
a) Trochlea of humerus
b) Capitulum of humerus
c) Head of radius
d) Head of ulna
Explanation: The radial notch is a shallow concavity on the lateral proximal ulna that articulates with the head of radius, forming the proximal radioulnar joint. This articulation is stabilized by annular ligament. Correct answer is Head of radius.
5. A patient with olecranon fracture will have difficulty in -
a) Making a fist
b) Extending elbow
c) Flexing wrist
d) Supinating forearm
Explanation: The olecranon fracture disrupts triceps insertion, thus impairing elbow extension. Wrist and hand movements are unaffected. Hence, the clinical problem is inability to extend elbow.
6. Which joint is formed by trochlear notch of ulna?
a) Proximal radioulnar joint
b) Elbow joint (humeroulnar part)
c) Distal radioulnar joint
d) Wrist joint
Explanation: The trochlear notch of ulna articulates with trochlea of humerus, forming the humeroulnar part of the elbow joint. This is responsible for hinge-like flexion and extension. Correct answer is Elbow joint (humeroulnar part).
7. The posterior surface of olecranon is attachment for?
a) Triceps tendon
b) Anconeus
c) Brachialis
d) Supinator
Explanation: The posterior surface of olecranon provides attachment for anconeus muscle in addition to triceps insertion. Brachialis inserts on coronoid process, supinator attaches near proximal radius. Correct answer is Anconeus.
8. A child falls and fractures proximal ulna near olecranon. Which nerve is most at risk?
a) Radial nerve
b) Median nerve
c) Ulnar nerve
d) Axillary nerve
Explanation: The ulnar nerve runs posterior to medial epicondyle and can be injured with proximal ulna fractures near olecranon. This produces sensory loss in medial fingers and intrinsic hand weakness. Correct answer is Ulnar nerve.
9. The coronoid process provides attachment to?
a) Triceps
b) Biceps
c) Brachialis
d) Supinator
Explanation: The coronoid process gives insertion to brachialis muscle, which is the chief flexor of the elbow. Biceps inserts on radial tuberosity, triceps on olecranon, supinator on proximal radius. Correct answer is Brachialis.
10. A 45-year-old male with posterior elbow trauma has inability to extend elbow and swelling over olecranon. Likely diagnosis?
a) Radial head fracture
b) Olecranon process fracture
c) Capitulum fracture
d) Coronoid process fracture
Explanation: Direct trauma to posterior elbow with loss of extension indicates olecranon process fracture, as it disrupts triceps tendon insertion. Other options present differently. Correct diagnosis is Olecranon process fracture.
Topic: Shoulder Girdle
Subtopic: Clavicle
Keyword Definitions:
Clavicle: S-shaped long bone connecting sternum to scapula, forming part of shoulder girdle.
Endochondral ossification: Bone formation from a cartilage template, typical of long bones.
Medullary cavity: Central hollow space of long bones containing bone marrow.
Fracture: Break in bone continuity.
Vertical orientation: Alignment of bone along long axis.
Lead Question - 2014
True about clavicle?
a) Endochondral ossification
b) Vertical
c) No medullary cavity
d) Rarely fractures
Explanation: The clavicle is unique as it undergoes intramembranous ossification predominantly, has a horizontal S-shaped orientation, possesses a medullary cavity, and is commonly fractured, especially at the middle third. Therefore, options a, b, c, and d are incorrect; correct features are intramembranous ossification, horizontal, medullary cavity present, and frequently fractures.
Guessed Questions
1. Middle third of clavicle is fractured commonly due to?
a) Direct trauma
b) Indirect trauma
c) Stress fracture
d) Pathological fracture
Explanation: The middle third of clavicle is the thinnest and lacks ligamentous support, making it most susceptible to fractures from direct trauma, especially falls on shoulder. Stress and pathological fractures are rare. Correct answer is Direct trauma.
2. Primary ossification of clavicle occurs at?
a) Lateral end
b) Medial end
c) Middle third
d) Both ends simultaneously
Explanation: Clavicle is the first bone to ossify in embryo, mainly by intramembranous ossification from two primary centers: medial and lateral ends. Ossification starts at medial end around 5th-6th week and lateral later. Correct answer is Medial end.
3. Which ossification type is predominant in clavicle?
a) Endochondral
b) Intramembranous
c) Mixed
d) Periosteal only
Explanation: The clavicle is unique as it is primarily formed by intramembranous ossification, although lateral end may have some endochondral component. Most long bones form via endochondral ossification. Correct answer is Intramembranous.
4. Clavicle articulates medially with?
a) Scapula
b) Sternum
c) Acromion
d) Humerus
Explanation: Medially, the clavicle articulates with the manubrium of sternum forming sternoclavicular joint. Laterally, it articulates with acromion of scapula. Humerus articulates with glenoid cavity. Correct answer is Sternum.
5. Lateral end of clavicle articulates with?
a) Sternum
b) Acromion
c) Coracoid process
d) Humeral head
Explanation: The lateral end of clavicle articulates with acromion process of scapula forming acromioclavicular joint, stabilized by coracoclavicular ligaments. Sternum and humerus are not lateral articulations. Correct answer is Acromion.
6. Clavicle lacks which typical long bone feature?
a) Medullary cavity
b) Epiphyses
c) Diaphysis
d) Periosteum
Explanation: Clavicle has medullary cavity, diaphysis, and periosteum like other long bones. It has two epiphyses—sternal and acromial ends—so it does not lack epiphyses. Correct answer is None of these if present; otherwise all typical features exist.
7. Fracture of lateral clavicle can injure?
a) Subclavian artery
b) Axillary nerve
c) Brachial plexus
d) Subclavian vein
Explanation: Fracture of lateral third clavicle rarely injures subclavian vessels due to lateral position; medial third fractures may injure subclavian artery/vein. Axillary nerve injury is uncommon. Correct answer is Subclavian vein for medial involvement; lateral fractures are safer.
8. Clavicle is palpable along its length except?
a) Medial end
b) Middle third
c) Lateral end
d) None
Explanation: The clavicle is subcutaneous along entire length, making it easily palpable. Middle third is most prominent, medial end near sternum less so, lateral end near acromion is palpable. Correct answer is None, as all parts are palpable.
9. Which ligament stabilizes lateral clavicle?
a) Coracoclavicular ligament
b) Sternoclavicular ligament
c) Interclavicular ligament
d) Costoclavicular ligament
Explanation: The coracoclavicular ligament stabilizes lateral clavicle, connecting it to coracoid process. Sternoclavicular ligament stabilizes medial end, interclavicular across manubrium, costoclavicular to first rib. Correct answer is Coracoclavicular ligament.
10. Ossification of clavicle is complete by?
a) Birth
b) 5 years
c) 25 years
d) 15 years
Explanation: Clavicle is first bone to ossify and last to complete ossification. Lateral epiphysis fuses by 18–25 years. Thus, ossification is complete around 25 years.
Topic: Pectoral Region
Subtopic: Clavipectoral Fascia
Keyword Definitions:
Clavipectoral fascia: Deep fascia beneath pectoralis major, enclosing subclavius and pectoralis minor, extending from clavicle to axilla.
Lateral pectoral nerve: Nerve supplying pectoralis major, passes through clavipectoral fascia.
Median pectoral nerve: Nerve supplying pectoralis minor and part of major, pierces fascia near axilla.
Thoracoacromial vessels: Artery and vein branching from axillary vessels, pierce fascia near pectoralis minor.
Cephalic vein: Superficial vein of upper limb, runs in deltopectoral groove but does not pierce fascia.
Lead Question - 2014
Clavipectoral fascia is pierced by all except?
a) Lateral pectoral nerve
b) Median pectoral nerve
c) Thoracoacromial vessels
d) Cephalic vein
Explanation: The clavipectoral fascia is pierced by the lateral pectoral nerve, median pectoral nerve, and thoracoacromial vessels. However, the cephalic vein runs superficial in the deltopectoral groove and does not pierce the fascia. Therefore, the correct answer is Cephalic vein.
Guessed Questions
1. Lateral pectoral nerve primarily supplies?
a) Pectoralis minor
b) Pectoralis major
c) Subclavius
d) Serratus anterior
Explanation: The lateral pectoral nerve mainly supplies the pectoralis major muscle, especially its clavicular part. It passes through the clavipectoral fascia near pectoralis minor but does not innervate minor or other muscles. Correct answer is Pectoralis major.
2. Median pectoral nerve supplies?
a) Pectoralis major only
b) Pectoralis minor only
c) Pectoralis minor and part of major
d) Deltoid
Explanation: The median pectoral nerve pierces the clavipectoral fascia to supply pectoralis minor and the lower fibers of pectoralis major. It does not supply deltoid. Correct answer is Pectoralis minor and part of major.
3. Thoracoacromial artery branches into all except?
a) Pectoral branch
b) Acromial branch
c) Clavicular branch
d) Lateral thoracic branch
Explanation: The thoracoacromial artery pierces the clavipectoral fascia and branches into pectoral, acromial, clavicular, and deltoid branches. Lateral thoracic artery is separate from axillary artery. Correct answer is Lateral thoracic branch.
4. Cephalic vein drains into?
a) Axillary vein
b) Subclavian vein
c) Basilic vein
d) Brachial vein
Explanation: The superficial cephalic vein runs in deltopectoral groove and drains into the axillary vein near clavipectoral fascia. It does not pierce the fascia. Correct answer is Axillary vein.
5. Clavipectoral fascia encloses which muscles?
a) Pectoralis major
b) Pectoralis minor and subclavius
c) Deltoid
d) Serratus anterior
Explanation: The clavipectoral fascia lies deep to pectoralis major and encloses pectoralis minor and subclavius muscles. It does not enclose deltoid or serratus anterior. Correct answer is Pectoralis minor and subclavius.
6. Deltopectoral triangle is bounded by?
a) Clavicle, deltoid, pectoralis major
b) Scapula, deltoid, trapezius
c) Clavicle, trapezius, pectoralis minor
d) Deltoid, biceps, coracoid
Explanation: The deltopectoral triangle is formed by clavicle superiorly, deltoid laterally, and pectoralis major medially. It contains the cephalic vein and deltopectoral lymph nodes. Correct answer is Clavicle, deltoid, pectoralis major.
7. Clavipectoral fascia attaches inferiorly to?
a) First rib
b) Sternum
c) Axillary fascia
d) Coracoid process
Explanation: The clavipectoral fascia descends from clavicle and attaches inferiorly to the axillary fascia and encases subclavius and pectoralis minor. Correct answer is Axillary fascia.
8. Lateral pectoral nerve communicates with?
a) Medial pectoral nerve
b) Axillary nerve
c) Musculocutaneous nerve
d) Radial nerve
Explanation: The lateral pectoral nerve communicates with medial pectoral nerve around clavipectoral fascia, forming a nerve loop to pectoralis major. It does not communicate with axillary, musculocutaneous, or radial nerves. Correct answer is Medial pectoral nerve.
9. Piercing of clavipectoral fascia by vessels allows?
a) Superficial drainage
b) Nerve passage
c) Communication between axilla and pectoral region
d) Fat deposition
Explanation: Piercing of the fascia by thoracoacromial vessels and nerves allows communication between axilla and pectoral region and passage of nerves and vessels to superficial muscles. Correct answer is Communication between axilla and pectoral region.
10. Subclavius muscle pierces clavipectoral fascia?
a) Yes
b) No
c) Partially
d) Only medial fibers
Explanation: The subclavius muscle lies enclosed within the clavipectoral fascia; it does not pierce it. Only nerves and vessels pierce the fascia. Correct answer is No.
Topic: Reflexes
Subtopic: Supinator (Brachioradialis) Reflex
Keyword Definitions:
Supinator jerk: Also called brachioradialis reflex, elicited by tapping brachioradialis tendon, leading to forearm flexion and supination.
Reflex arc: Neural pathway that mediates a reflex action, involving sensory input, spinal cord integration, and motor output.
C5, C6 roots: Cervical spinal nerve roots contributing to supinator (brachioradialis) reflex.
Neurological examination: Assessment of reflexes helps localize lesions in spinal cord or peripheral nerves.
Clinical relevance: Supinator jerk tests integrity of C5-C6 nerve roots and musculocutaneous/ radial nerves.
Lead Question - 2014
Root value of supinator jerk?
a) C3-C4
b) C4-C5
c) C5-C6
d) C8-T1
Explanation: The supinator (brachioradialis) jerk involves tapping the tendon of brachioradialis, causing flexion and supination of the forearm. This reflex is mediated by the C5-C6 spinal nerve roots. Correct answer is C5-C6.
Guessed Questions
1. Biceps jerk tests which nerve roots?
a) C5-C6
b) C6-C7
c) C7-C8
d) C8-T1
Explanation: The biceps jerk is elicited by tapping the biceps tendon, causing forearm flexion. It tests integrity of C5-C6 nerve roots and musculocutaneous nerve. Correct answer is C5-C6.
2. Triceps jerk assesses?
a) C5-C6
b) C6-C7
c) C7-C8
d) C8-T1
Explanation: The triceps reflex is elicited by tapping the triceps tendon, causing elbow extension. It tests C7-C8 roots and radial nerve function. Correct answer is C7-C8.
3. Supinator jerk is mediated by which nerve?
a) Median nerve
b) Musculocutaneous nerve
c) Radial nerve
d) Ulnar nerve
Explanation: The supinator jerk reflex involves contraction of brachioradialis, mediated by the radial nerve, with sensory input from C5-C6 roots. Correct answer is Radial nerve.
4. Forearm supination in supinator reflex tests integrity of?
a) Muscles only
b) Spinal cord only
c) C5-C6 roots and radial nerve
d) Peripheral nerves only
Explanation: Supinator jerk causes forearm supination, testing C5-C6 nerve roots and radial nerve. Both peripheral nerve and spinal roots must be intact. Correct answer is C5-C6 roots and radial nerve.
5. Absence of supinator jerk suggests?
a) Normal reflex
b) Upper motor neuron lesion
c) Lower motor neuron lesion at C5-C6
d) Cerebellar lesion
Explanation: Absence or diminution of supinator jerk indicates lower motor neuron lesion affecting C5-C6 nerve roots or radial nerve. Upper motor neuron lesions usually cause hyperreflexia. Correct answer is Lower motor neuron lesion at C5-C6.
6. Reinforcement technique for supinator reflex?
a) Jendrassik maneuver
b) Deep breath
c) Leg crossing
d) Valsalva maneuver
Explanation: Jendrassik maneuver (clenching teeth or interlocking fingers) enhances supinator reflex by increasing central excitability. Correct answer is Jendrassik maneuver.
7. Supinator reflex is classified as?
a) Superficial reflex
b) Deep tendon reflex
c) Pathological reflex
d) Cranial reflex
Explanation: The supinator jerk is a deep tendon reflex, elicited by tapping the tendon, involving monosynaptic reflex arc and testing spinal nerve root integrity. Correct answer is Deep tendon reflex.
8. Clinical significance of exaggerated supinator jerk?
a) LMN lesion
b) UMN lesion
c) Peripheral neuropathy
d) Muscle rupture
Explanation: Exaggerated or hyperactive supinator jerk indicates upper motor neuron lesion above C5-C6 level, causing hyperreflexia. Correct answer is UMN lesion.
9. Supinator reflex primarily tests which muscle?
a) Biceps brachii
b) Brachioradialis
c) Triceps brachii
d) Supinator muscle
Explanation: Supinator jerk is elicited by tapping the tendon of brachioradialis, causing forearm flexion and supination. Though supinator muscle participates in supination, the primary muscle tested is brachioradialis. Correct answer is Brachioradialis.
10. Supinator jerk is decreased in which condition?
a) Cervical radiculopathy C5-C6
b) Carpal tunnel syndrome
c) Cubital tunnel syndrome
d) Rotator cuff tear
Explanation: Supinator reflex is reduced or absent in cervical radiculopathy involving C5-C6 because the nerve roots and radial nerve contribution are impaired. Peripheral neuropathies in distal nerves do not affect this reflex. Correct answer is Cervical radiculopathy C5-C6.
Topic: Upper Limb
Subtopic: Hand Muscles Innervation
Keyword Definitions:
Small muscles of hand: Intrinsic hand muscles including thenar, hypothenar, lumbricals, and interossei, responsible for fine motor movements.
Innervation: Nerve supply to muscles, determining motor function.
C5-T1 roots: Spinal nerve roots forming the brachial plexus supplying upper limb muscles.
Median nerve: Nerve supplying thenar muscles and lateral two lumbricals.
Ulnar nerve: Nerve supplying hypothenar muscles, interossei, and medial two lumbricals.
Lead Question - 2014
Small muscles of hand are supplied by:
a) C3
b) C4
c) C6
d) C5-C7 , C8-T1
Explanation: The small intrinsic muscles of the hand are supplied by nerves originating from C5-C7 (median nerve) and C8-T1 (ulnar nerve). These roots form the brachial plexus, allowing fine motor control. Correct answer is C5-C7 , C8-T1.
Guessed Questions
1. Thenar muscles are supplied by?
a) Ulnar nerve
b) Median nerve
c) Radial nerve
d) Musculocutaneous nerve
Explanation: Thenar muscles controlling thumb movements are innervated by the median nerve, derived from C5-C7 roots of the brachial plexus. Ulnar nerve does not supply thenar muscles except adductor pollicis. Correct answer is Median nerve.
2. Hypothenar muscles are supplied by?
a) Median nerve
b) Ulnar nerve
c) Radial nerve
d) Axillary nerve
Explanation: Hypothenar muscles (flexor digiti minimi, abductor digiti minimi, opponens digiti minimi) controlling little finger movements are supplied by the ulnar nerve arising from C8-T1 roots. Correct answer is Ulnar nerve.
3. Lumbrical muscles innervation?
a) Median for all
b) Ulnar for all
c) Median for lateral two, Ulnar for medial two
d) Radial nerve
Explanation: Lumbricals 1 and 2 (lateral) are supplied by median nerve, lumbricals 3 and 4 (medial) by ulnar nerve. This allows coordinated finger flexion at MCP joints and extension at IP joints. Correct answer is Median for lateral two, Ulnar for medial two.
4. Interossei muscles are supplied by?
a) Median nerve
b) Ulnar nerve
c) Radial nerve
d) Axillary nerve
Explanation: Dorsal and palmar interossei of the hand, responsible for finger abduction and adduction, are supplied by ulnar nerve (C8-T1). Median nerve does not supply interossei. Correct answer is Ulnar nerve.
5. Injury to C8-T1 roots affects?
a) Shoulder abduction
b) Elbow flexion
c) Intrinsic hand muscles
d) Wrist extension
Explanation: C8-T1 nerve roots supply the intrinsic hand muscles via ulnar and median nerves. Damage results in weakness of fine motor control, claw hand deformity. Shoulder and elbow muscles are supplied by higher roots. Correct answer is Intrinsic hand muscles.
6. Claw hand is due to injury of?
a) Median nerve
b) Ulnar nerve
c) Both median and ulnar nerves
d) Radial nerve
Explanation: Claw hand deformity occurs when ulnar nerve is injured, leading to hyperextension at MCP and flexion at IP joints. Combined median and ulnar nerve lesions worsen intrinsic hand function. Correct answer is Both median and ulnar nerves.
7. Ape hand deformity is due to?
a) Median nerve injury
b) Ulnar nerve injury
c) Radial nerve injury
d) Axillary nerve injury
Explanation: Ape hand results from median nerve injury, causing loss of thumb opposition, atrophy of thenar muscles, and flattening of thenar eminence. Correct answer is Median nerve injury.
8. Median nerve arises from which roots?
a) C5-C6
b) C5-C7
c) C8-T1
d) C7-T1
Explanation: Median nerve originates from the brachial plexus, receiving contributions from C5-C7 (lateral cord) and C8-T1 (medial cord). Supplies most thenar muscles and lateral lumbricals. Correct answer is C5-C7.
9. Ulnar nerve arises from?
a) Lateral cord
b) Medial cord
c) Posterior cord
d) Musculocutaneous nerve
Explanation: Ulnar nerve arises from medial cord of brachial plexus (C8-T1), supplying hypothenar muscles, medial lumbricals, and interossei. Correct answer is Medial cord.
10. Fine motor control of hand depends on?
a) Only extrinsic muscles
b) Only intrinsic muscles
c) Intrinsic and extrinsic muscles
d) Only wrist muscles
Explanation: Fine hand movements require coordinated action of intrinsic muscles (thenar, hypothenar, interossei, lumbricals) and extrinsic muscles (flexors/extensors of forearm). Both median and ulnar nerves contribute. Correct answer is Intrinsic and extrinsic muscles.
Topic: Upper Limb
Subtopic: Cubital Fossa Structures
Keyword Definitions:
Bicipital aponeurosis: A broad fibrous expansion from biceps brachii tendon crossing cubital fossa, protecting underlying structures.
Cubital fossa: Triangular area anterior to elbow joint, containing important nerves and vessels.
Brachial artery: Main artery of upper arm continuing from axillary artery to cubital fossa.
Ulnar nerve: Nerve passing medial to cubital fossa, supplying intrinsic hand muscles.
Anterior interosseous artery: Branch of ulnar artery running along forearm interosseous membrane.
Lead Question - 2014
Bicipital aponeurosis lies over which structure in cubital fossa?
a) Ulnar nerve
b) Radial nerve
c) Brachial artery
d) Anterior interosseous artery
Explanation: The bicipital aponeurosis is a fibrous expansion from the biceps tendon that lies superficial to the brachial artery in the cubital fossa, providing protection to this major vessel during venipuncture or trauma. Correct answer is Brachial artery.
Guessed Questions
1. Ulnar nerve lies medial to which structure in cubital fossa?
a) Brachial artery
b) Bicipital aponeurosis
c) Median nerve
d) Radial artery
Explanation: The ulnar nerve passes medial to the cubital fossa, lying behind the medial epicondyle and not under the bicipital aponeurosis. Correct answer is Brachial artery lies anterior to it, but ulnar nerve is medial to cubital fossa structures.
2. Median nerve in cubital fossa is located?
a) Lateral to brachial artery
b) Medial to brachial artery
c) Superficial to bicipital aponeurosis
d) Posterior to brachial artery
Explanation: The median nerve lies medial to the brachial artery in cubital fossa and deep to the bicipital aponeurosis, ensuring protection during venipuncture. Correct answer is Medial to brachial artery.
3. Bicipital aponeurosis prevents injury to?
a) Radial nerve
b) Brachial artery
c) Ulnar artery
d) Median cubital vein
Explanation: The bicipital aponeurosis covers the brachial artery and median nerve in cubital fossa, protecting them from superficial lacerations during venipuncture or trauma. Correct answer is Brachial artery.
4. Cephalic vein in cubital fossa lies relative to bicipital aponeurosis?
a) Superficial
b) Deep
c) Lateral
d) Medial
Explanation: The cephalic vein lies superficial to the bicipital aponeurosis in the cubital fossa, allowing easy access for venipuncture without injuring deeper structures. Correct answer is Superficial.
5. Anterior interosseous artery is branch of?
a) Radial artery
b) Brachial artery
c) Ulnar artery
d) Median artery
Explanation: The anterior interosseous artery arises from the ulnar artery, passes along the interosseous membrane supplying deep flexor muscles of forearm. It is not covered by bicipital aponeurosis. Correct answer is Ulnar artery.
6. Structures passing deep to bicipital aponeurosis?
a) Median cubital vein
b) Brachial artery
c) Cephalic vein
d) Superficial radial nerve
Explanation: Brachial artery and median nerve lie deep to the bicipital aponeurosis in cubital fossa, providing protection from superficial trauma. Superficial veins lie above the aponeurosis. Correct answer is Brachial artery.
7. Radial nerve in cubital fossa lies?
a) Medial to biceps tendon
b) Lateral and deep to brachioradialis
c) Superficial to brachialis
d) Under bicipital aponeurosis
Explanation: The radial nerve passes laterally, deep to brachioradialis, and does not lie under the bicipital aponeurosis. Correct answer is Lateral and deep to brachioradialis.
8. Median cubital vein is located?
a) Superficial to bicipital aponeurosis
b) Deep to bicipital aponeurosis
c) Deep to brachial artery
d) Between brachial artery and ulnar nerve
Explanation: Median cubital vein is superficial to the bicipital aponeurosis, connecting cephalic and basilic veins in cubital fossa, commonly used for venipuncture. Correct answer is Superficial to bicipital aponeurosis.
9. Clinical importance of bicipital aponeurosis?
a) Protects brachial artery
b) Guides venipuncture
c) Can be injured in lacerations
d) All of the above
Explanation: The bicipital aponeurosis protects brachial artery and median nerve, provides a landmark for venipuncture, and may be injured in trauma. Correct answer is All of the above.
10. Injury under bicipital aponeurosis may affect?
a) Radial nerve
b) Median nerve
c) Cephalic vein
d) Basilic vein
Explanation: Structures deep to bicipital aponeurosis include brachial artery and median nerve. Injury here can cause hemorrhage and loss of hand function. Radial nerve lies laterally and cephalic vein superficially. Correct answer is Median nerve.
Topic: Upper Limb
Subtopic: Cubital Fossa Structures
Keyword Definitions:
Bicipital aponeurosis: Fibrous expansion from biceps tendon crossing cubital fossa, protecting underlying brachial artery and median nerve.
Cubital fossa: Triangular area anterior to elbow joint, containing important nerves, arteries, and veins.
Brachial artery: Main artery of upper arm, continuation of axillary artery, lies deep to bicipital aponeurosis.
Veins: Superficial veins like median cubital, cephalic, and basilic veins lie above bicipital aponeurosis.
Ulnar nerve: Passes medial to cubital fossa, not over bicipital aponeurosis.
Radial nerve: Lateral to cubital fossa, deep to brachioradialis, not over aponeurosis.
Lead Question - 2014
Structure over bicipital aponeurosis in cubital fossa?
a) Ulnar nerve
b) Radial nerve
c) Brachial artery
d) Veins
Explanation: Superficial veins such as median cubital vein lie over the bicipital aponeurosis in the cubital fossa, making them easily accessible for venipuncture. Deep structures like brachial artery and median nerve lie beneath the aponeurosis. Correct answer is Veins.
Guessed Questions
1. Median cubital vein connects?
a) Cephalic and basilic veins
b) Brachial and radial arteries
c) Ulnar and radial nerves
d) Median and ulnar nerves
Explanation: The median cubital vein forms a connection between the superficial cephalic and basilic veins in the cubital fossa. It lies above the bicipital aponeurosis and is the preferred site for venipuncture. Correct answer is Cephalic and basilic veins.
2. Which nerve is deep to bicipital aponeurosis?
a) Radial nerve
b) Median nerve
c) Ulnar nerve
d) Musculocutaneous nerve
Explanation: The median nerve passes deep to the bicipital aponeurosis along with the brachial artery in the cubital fossa, protecting it from superficial trauma. Correct answer is Median nerve.
3. Brachial artery lies in relation to bicipital aponeurosis?
a) Superficial
b) Deep
c) Lateral
d) Medial
Explanation: The brachial artery lies deep to the bicipital aponeurosis in the cubital fossa, making the aponeurosis a protective layer during trauma or venipuncture. Correct answer is Deep.
4. Clinical importance of bicipital aponeurosis?
a) Protects brachial artery
b) Guides venipuncture
c) Prevents nerve injury
d) All of the above
Explanation: The bicipital aponeurosis protects underlying structures, including the brachial artery and median nerve, serves as landmark for venipuncture, and minimizes risk of vascular or nerve injury. Correct answer is All of the above.
5. Cephalic vein lies relative to bicipital aponeurosis?
a) Superficial
b) Deep
c) Lateral
d) Medial
Explanation: The cephalic vein is a superficial vein lying above the bicipital aponeurosis, allowing easy access for venipuncture. Deep structures remain protected. Correct answer is Superficial.
6. Structures NOT protected by bicipital aponeurosis?
a) Brachial artery
b) Median nerve
c) Superficial veins
d) Median cubital vein
Explanation: Superficial veins like the median cubital vein lie above the bicipital aponeurosis, and thus are not protected by it, making them vulnerable but easily accessible for venipuncture. Correct answer is Superficial veins.
7. Radial nerve in cubital fossa lies?
a) Medial to biceps tendon
b) Lateral and deep to brachioradialis
c) Superficial to brachialis
d) Over bicipital aponeurosis
Explanation: The radial nerve passes lateral to the cubital fossa, deep to brachioradialis, and does not lie over or under the bicipital aponeurosis. Correct answer is Lateral and deep to brachioradialis.
8. Injury above bicipital aponeurosis can affect?
a) Superficial veins
b) Median nerve
c) Brachial artery
d) Anterior interosseous artery
Explanation: Superficial lacerations above the bicipital aponeurosis primarily affect veins such as median cubital, while deeper structures are protected. Correct answer is Superficial veins.
9. Landmark for venipuncture in cubital fossa?
a) Brachial artery
b) Median cubital vein
c) Bicipital aponeurosis
d) Radial nerve
Explanation: The median cubital vein, superficial to the bicipital aponeurosis, is the preferred landmark for venipuncture because it is easily palpable and accessible without risk to deeper structures. Correct answer is Median cubital vein.
10. Structure lying deep to bicipital aponeurosis?
a) Cephalic vein
b) Median nerve
c) Superficial radial nerve
d) Basilic vein
Explanation: The median nerve lies deep to the bicipital aponeurosis in the cubital fossa along with brachial artery, protected from superficial injury. Superficial veins lie above the aponeurosis. Correct answer is Median nerve.
Topic: Upper Limb
Subtopic: Brachial Artery and Radial Nerve Relations
Keyword Definitions:
Profunda brachii artery: Deep branch of brachial artery, runs in the spiral groove of humerus, supplies posterior compartment of arm.
Spiral groove: Groove on posterior aspect of humerus where radial nerve and profunda brachii artery travel together.
Radial nerve: Nerve of posterior compartment of arm, supplies triceps and forearm extensors, runs with profunda brachii artery in spiral groove.
Ulnar nerve: Runs medial arm, behind medial epicondyle, unrelated to profunda brachii artery.
Median nerve: Runs with brachial artery in anterior compartment of arm.
Lead Question - 2014
Nerve running along with profunda brachii artery, in spiral groove?
a) Ulnar
b) Median
c) Radial
d) None
Explanation: The radial nerve runs in the spiral groove of humerus alongside the profunda brachii artery, supplying the posterior compartment of the arm. Injury here can lead to wrist drop. Correct answer is Radial.
Guessed Questions
1. Nerve vulnerable in mid-shaft humerus fracture?
a) Median
b) Radial
c) Ulnar
d) Musculocutaneous
Explanation: Mid-shaft humerus fractures can injure the radial nerve as it lies in the spiral groove along with the profunda brachii artery. This can cause wrist drop and sensory deficits over dorsum of hand. Correct answer is Radial.
2. Profunda brachii artery is a branch of?
a) Axillary artery
b) Brachial artery
c) Subclavian artery
d) Radial artery
Explanation: The profunda brachii artery is the deep branch of the brachial artery, running in the posterior compartment of arm alongside the radial nerve in the spiral groove. Correct answer is Brachial artery.
3. Muscle supplied by nerve in spiral groove?
a) Biceps brachii
b) Triceps brachii
c) Brachialis
d) Pronator teres
Explanation: The radial nerve running in the spiral groove supplies the triceps brachii muscle of posterior compartment. Injury at this site affects elbow extension. Correct answer is Triceps brachii.
4. Sensory area of radial nerve in arm?
a) Medial forearm
b) Dorsum of lateral hand
c) Palm of hand
d) Posterior arm only
Explanation: The radial nerve provides sensory innervation to the dorsum of lateral hand and posterior arm/forearm. Mid-shaft injury in spiral groove can cause sensory deficits here. Correct answer is Dorsum of lateral hand.
5. Complication of radial nerve injury in spiral groove?
a) Claw hand
b) Wrist drop
c) Foot drop
d) Ape hand
Explanation: Injury to the radial nerve in the spiral groove leads to wrist drop due to paralysis of wrist extensors, while elbow extension may be preserved. Correct answer is Wrist drop.
6. Spiral groove is located on?
a) Anterior humerus
b) Posterior humerus
c) Medial epicondyle
d) Lateral epicondyle
Explanation: The spiral groove is a groove on the posterior aspect of the humerus where the radial nerve and profunda brachii artery travel together. Correct answer is Posterior humerus.
7. Nerve supplying forearm extensors?
a) Median
b) Radial
c) Ulnar
d) Musculocutaneous
Explanation: The radial nerve, after running in spiral groove with profunda brachii artery, continues to innervate forearm extensors. Injury leads to weakness in wrist and finger extension. Correct answer is Radial.
8. Profunda brachii artery enters posterior compartment via?
a) Triangular interval
b) Quadrangular space
c) Cubital fossa
d) Medial intermuscular septum
Explanation: The profunda brachii artery enters the posterior compartment of arm through the triangular interval, running with the radial nerve in spiral groove. Correct answer is Triangular interval.
9. Clinical test for radial nerve injury?
a) Elbow flexion test
b) Wrist extension test
c) Thumb opposition test
d) Finger abduction test
Explanation: The wrist extension test assesses function of the radial nerve. Injury in spiral groove causes wrist drop, inability to extend wrist. Correct answer is Wrist extension test.
10. Surgical landmark for profunda brachii artery?
a) Lateral epicondyle
b) Spiral groove of humerus
c) Medial epicondyle
d) Olecranon
Explanation: The spiral groove of humerus is the surgical landmark where the profunda brachii artery runs with radial nerve. Knowledge helps prevent iatrogenic injury. Correct answer is Spiral groove of humerus.
Topic: Shoulder Region
Subtopic: Quadrilateral Space
Keyword Definitions:
Quadrilateral space: Anatomical space in posterior shoulder, transmits axillary nerve and posterior circumflex humeral artery.
Teres major: Muscle forming lower border of quadrilateral space.
Teres minor: Muscle forming upper border along with subscapularis and shoulder capsule.
Long head of triceps: Forms medial border of quadrilateral space.
Deltoid: Muscle overlying shoulder, not a boundary of quadrilateral space.
Neck of humerus: Lateral border of quadrilateral space.
Axillary nerve: Passes through quadrilateral space with posterior circumflex humeral artery.
Lead Question - 2014
Boundaries of quadrilateral space include all except?
a) Teres major
b) Long head of triceps
c) Neck of humerus
d) Deltoid
Explanation: The quadrilateral space is bordered superiorly by teres minor, inferiorly by teres major, medially by the long head of triceps, and laterally by the neck of humerus. The deltoid overlies the region but is not a boundary. Correct answer is Deltoid.
Guessed Questions
1. Nerve passing through quadrilateral space?
a) Radial nerve
b) Axillary nerve
c) Musculocutaneous nerve
d) Ulnar nerve
Explanation: The axillary nerve passes through the quadrilateral space along with posterior circumflex humeral artery, innervating deltoid and teres minor. Correct answer is Axillary nerve.
2. Artery passing through quadrilateral space?
a) Brachial artery
b) Posterior circumflex humeral artery
c) Subclavian artery
d) Radial artery
Explanation: The posterior circumflex humeral artery passes through the quadrilateral space with axillary nerve, supplying deltoid and shoulder joint. Correct answer is Posterior circumflex humeral artery.
3. Muscle forming superior border of quadrilateral space?
a) Teres major
b) Teres minor
c) Deltoid
d) Subscapularis
Explanation: The teres minor muscle forms the superior border of quadrilateral space, with teres major forming the inferior border. Correct answer is Teres minor.
4. Muscle forming medial border of quadrilateral space?
a) Long head of triceps
b) Lateral head of triceps
c) Deltoid
d) Supraspinatus
Explanation: The long head of triceps forms the medial border of the quadrilateral space, contributing to the safe passage of axillary nerve. Correct answer is Long head of triceps.
5. Lateral border of quadrilateral space?
a) Humeral shaft
b) Neck of humerus
c) Deltoid
d) Coracobrachialis
Explanation: The neck of humerus forms the lateral border of the quadrilateral space, providing a landmark for axillary nerve and posterior circumflex humeral artery passage. Correct answer is Neck of humerus.
6. Clinical test for axillary nerve injury?
a) Shoulder abduction against resistance
b) Elbow flexion
c) Wrist extension
d) Thumb opposition
Explanation: Axillary nerve injury can be assessed by testing shoulder abduction against resistance, as the deltoid is paralyzed. Sensory loss occurs over lateral shoulder. Correct answer is Shoulder abduction against resistance.
7. Fracture of surgical neck of humerus may damage?
a) Radial nerve
b) Axillary nerve
c) Median nerve
d) Ulnar nerve
Explanation: Fracture of the surgical neck of humerus may injure the axillary nerve passing through the quadrilateral space, causing deltoid paralysis and sensory deficit over lateral shoulder. Correct answer is Axillary nerve.
8. Muscle not contributing to quadrilateral space?
a) Teres minor
b) Deltoid
c) Teres major
d) Long head of triceps
Explanation: The deltoid overlies the quadrilateral space but does not form its boundary. Teres minor, teres major, and long head of triceps form superior, inferior, and medial borders respectively. Correct answer is Deltoid.
9. Posterior circumflex humeral artery arises from?
a) Axillary artery
b) Brachial artery
c) Subclavian artery
d) Radial artery
Explanation: The posterior circumflex humeral artery is a branch of the axillary artery passing through the quadrilateral space with axillary nerve. Correct answer is Axillary artery.
10. Injury to axillary nerve leads to?
a) Weak elbow extension
b) Weak shoulder abduction
c) Weak wrist flexion
d) Weak finger abduction
Explanation: Damage to the axillary nerve results in weakness of shoulder abduction due to deltoid paralysis and sensory loss over lateral shoulder. Correct answer is Weak shoulder abduction.