Upper Limb: Axilla Microbiology

Q-1. The medial wall of the axilla is formed by the
a) Serratus anterior
b) Sub-scapularis muscle
c) Pectoralis major muscle
d) Teres major muscle

Answer: Serratus anterior
Explanation:
The axilla:
It is truncated (not pointed), and corresponds to a triangular interval bounded anteriorly by the clavicle, posteriorly by the superior border of the scapula, and medially by the outer border of the first rib. This passage is called the cervi-coaxillary canal. The axillary artery and the brachial plexus enter the axilla through this canal.
Medial wall of axilla is formed by upper four ribs with their intercostal muscles and upper part of the serratus anterior muscle.

Q-2. The following structures form the boundaries to the superior entrance into the axilla except the
a) Clavicle
b) Coracoid process
c) Upper border of scapula
d) Outer border of first rib

Answer: Coracoid process
Explanation:
See above explanation.

Q-3. Fascia around nerve bundle of brachial plexus is derived from-
a) Pre-vertebral fascia
b) Pre-tracheal fascia
c) Investing layer
d) Superficial cervical fascia

Answer: Pre-vertebral fascia
Explanation:
The brachial plexus is surrounded by a sheath of fascia, the axillary sheath, which is derived from the pre-vertebral layer of deep cervical fascia.

Q-4. Concerning brachial plexus, which of the following facts are true-
a) Formed by spinal nerve C4-C7
b) Most common site of injury is upper trunk
c) Injury may occur during breech delivery
d) Radial nerve is branch of medial cord
e) Lower trunk injury result in hand deformity

Answer: b, c, and e
Explanation:
The brachial plexus is formed in posterior triangle of neck by union of the anterior rami of the 5th, 6th, 7th and 8th cervical and the first thoracic spinal nerve. Most common site of injury is upper trunk.
Branches of the Brachial Plexus for the Upper Limb:
Branches of the Roots:
Nerve to serratus anterior (long thoracic nerve) (C5, 6, 7)
Nerve to rhomboideus (dorsal scapular nerve) (C5)
Branches of the Trunks:
These arise only from the upper trunk which gives two branches:.
Supra-scapular nerve (C5, 6)
Nerve to sub-clavius (C5, 6)

Q-5. Root value of Musculo-cutaneous nerve is
a) C4, 5
b) C5, 6, 7
c) C5, 6, 7, 8
d) C8, T1

Answer: C5, 6, 7
Explanation:
Branches of Lateral Cord:
Lateral pectoral (C5-C7)
Musculo-cutaneous (C5-C7)
Lateral root of median (C5-C7)

Q-6. Medial cord of the brachial plexus gives rise to all except
a) Nerve to supra-spinatus
b) Ulnar nerve
c) Medial cutaneous nerve of arm
c) Medial cutaneous nerve of forearm

Answer: Nerve to supra-spinatus
Explanation:
Branches of medial Cord:
Medial pectoral (C8, T1)
Medial cutaneous nerve of arm (C8, T1)
Medial cutaneous nerve of forearm (C8, T1)
Ulnar (C7, C8 T1)
Medial root of median (C8, T1)

Q-7. Root value of ulnar nerve
a) C7 C8 T1
b) C7 C8 T1
c) C8 T1
d) C6 C7 C8
e) C5 C6 C7

Answer: C7 C8 T1
Explanation:
See above explanation.

Q-8. Axillary nerve arises from
a) Posterior cord
b) Lateral cord
c) Both medial and lateral cords
d) Upper trunk
e) None of the above

Answer: Posterior cord
Explanation:
Branches of Posterior Cord:
Upper sub-scapular (C5, C6)
Nerve to latissimus dorsi (thoraco-dorsal) (C6, C7, C8)
Lower sub-scapular 9C5, C6)
Axillary (circumflex) (C5, C6)
Radial (C5-C8, T1)

Q-9. The following is true of brachial plexus
a) Cervical rib involves lateral cord
b) Musculo-cutaneous nerve arises from medial cord
c) Radial nerve arises from posterior cord
d) Post fixed plexus is formed by C4, 5, 6, 7, 8 TI

Answer: Radial nerve arises from posterior cord
Explanation:
See above explanation.

Q-10. Which of the following nerves are branches of the posterior cord?
a) Radial nerve
b) Axillary nerve
c) Musculo-cutaneous nerve
d) Sub-clavius nerve
e) Lateral pectoral nerve

Answer: a and b
Explanation:
See above explanation.

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Q-11. Which is not a branch of posterior cord of Brachial plexus?
a) Thoraco-dorsal
b) Radial
c) Ulnar
d) Axillary

Answer: Ulnar
Explanation:
See above explanation.

Q-12. Root value of radial nerve is
a) C5, 6
b) C4, 5
c) C5, 6, 7, 8, TI
d) None

Answer: C5, 6, 7, 8, TI
Explanation:
See above explanation.

Q-13. Root value of axillary nerve is
a) C 5, 6
b) C4, 5
c) C5, 6, 7
d) C6, 7

Answer: C 5, 6
Explanation:
See above explanation.

Q-14. Small muscles of hand are supplied by
a) C6
b) C7
c) C8
d) T1
e) T2

Answer: c and d
Explanation:
See above explanation.

Q-15. In Erb-Duchene paralysis, the injury is limited to the
a) 2nd and 3rd cervical nerves
b) 3rd and 4th cervical nerves
c) 4th and 5th cervical nerves
d) 5th and 6th cervical nerves

Answer: 5th and 6th cervical nerves
Explanation:
Erb’s Paralysis:
Site of injury:
The region of the upper trunk of the brachial plexus is called Erb’s point. Six nerves meet here. Injury to the upper trunk causes Erb’s paralysis.
Nerve roots involved:
Mainly C5 and partly C6
Movements lost:
Abduction and lateral rotation of arm or shoulder
Flexion and supination of forearm
Sensations are lost over a small area over the lower part of the deltoid

Q-16. A 19 year old boy fell from the motor bike on his shoulder. The doctor diagnosed him a case of Erb’s paralysis. The following signs and symptoms will be observed except:
a) Loss of abduction at shoulder joint
b) Loss of lateral rotation
c) Loss of pronation at radio-ulnar joint.
d) Loss of flexion at elbow joint.

Answer: Loss of pronation at radio-ulnar joint.
Explanation:
See above explanation.

Q-17. Erb’s point is
a) Anterior primary rami of C5-6
b) Posterior primary rami of C6-7
c) Posterior primary rami of C8- T1
d) Posterior primary rami of C2-C8

Answer: Anterior primary rami of C5-6
Explanation:
See above explanation.

Q-18. A young boy who was driving motorcycle at a high speed collided with a tree & was thrown on his right shoulder. Though there was no fracture, his right arm was medially rotated and forearm pronated. The following facts concerning this patient are correct, except
a) The injury was at Erb’s point
b) A lesion of C5 and C6 was present
c) The median and ulnar nerves were affected
d) Supra-spinatus, Infra-spinatus, Sub-clavius & Biceps brachii were paralyzed

Answer: The median and ulnar nerves were affected Explanation:
See above explanation.
Muscles paralyzed in Erb’s paralysis are biceps, deltoid, brachialis and brachio-radialis. Partly supra-spinatus, infra-spinatus and supinator

Q-19. All of the following muscles undergo paralysis after injury of C5 and C6 spinal nerves except:
a) Biceps
b) Coraco-brachialis
c) Brachialis
d) Brachio-radialis

Answer: Coraco-brachialis
Explanation:
See above explanation.

Q-20. Erb’s point is formed by
a) C4 and C5
b) C5 and C6
c) C6 and C7
d) C8 and T1

Answer: C5 and C6
Explanation:
See above explanation.

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Q-21. In Klumpke’s paralysis all are involved, except
a) C6
b) C7
c) C8
d) T1

Answer: C6
Explanation:
Klumpke’s paralysis:
Site of injury:
Lower trunk of the brachial plexus
Cause of injury:
Undue abduction of the arm, as in clutching something with the hands after a fall from a height, or sometimes in birth injury
Nerve roots involved:
Mainly T1 and partly C8

Q-22. The lesion of Klumpke’s paralysis in
a) Cervical plexus
b) Lower brachial
c) Upper brachial
d) Sacral plexus

Answer: Lower brachial
Explanation:
See above explanation.

Q-23. After radical mastectomy there was injury to the long thoracic nerve. The integrity of the nerve can be tested at the bedside by asking the patient to:
a) Shrug the shoulders
b) Raise the arm above the head on the affected side
c) Touch the opposite shoulder
d) Lift a heavy object from the ground

Answer: Raise the arm above the head on the affected side
Explanation:
Injury to the nerve of Bell or serratus anterior:
Cause:
Sudden pressure on the shoulder from above
Carrying heavy loads on the shoulder
Disability:
Excessive prominence of the medial border of the scapula
Loss of punching and pushing action
Arm cannot be raised beyond 900 or overhead abduction is not possible.

Q-24. Relation of Musculo-cutaneous nerve with axillary artery in axilla is
a) Lateral
b) Medial
c) Anterior
d) Posterior

Answer: Lateral
Explanation:
Axillary Artery:
Relations of Third part:
Laterally:
Coraco-brachialis
Musculo-cutaneous nerve in the upper part
Lateral root of median nerve in the upper part
Trunk of median nerve in the lower part

Q-25. Following groups of axillary L.N. are distributed along lateral thoracic artery
a) Anterior set
b) Lateral set
c) Posterior set
d) Apical set

Answer: Anterior set
Explanation:
Axillary Lymph Nodes:
The nodes of the anterior (or pectoral) group lie along the lateral thoracic vessels (Along the lower border of the pectoralis minor). These nodes are in direct contact with the axillary tail of the breast. They receive lymph from the upper half of the anterior wall of the trunk, and from the major part of the breast.

Q-26. Arterial supply of latissimus dorsi is
a) Sub-scapular A
b) Circumflex humeral A
c) Thoraco-dorsal A
d) Lateral thoracic A

Answer: Sub-scapular A
Explanation:
Sub-scapular artery is the largest branch of the axillary artery, arising from its third part. It runs along the lower border of the sub-scapularis to terminate near the inferior angle of the scapula. It supplies the latissimus dorsi and the serratus anterior.

Q-27. In case of occlusion occurs at the 2nd part of Axillary artery, blood flow is maintained by collateral/ anastomosis between:
a) Anterior and posterior circumflex humoral artery
b) Supra-scapular and posterior circumflex artery
c) Deep branch of the transverse cervical artery and Sub-scapular artery
d) Anterior circumflex artery and sub-scapular artery

Answer: Deep branch of the transverse cervical artery and Sub-scapular artery
Explanation:
In case of occlusion occurs at the 2nd part of Axillary artery, blood flow is maintained by collateral/ anastomosis:
Internal thoracic, intercostal, supra-scapular, deep branch of transverse cervical, profunda brachii, sub-scapular and posterior circumflex humeral artery

Q-28. Which of the following, among axillary lymph nodes, is a terminal group?
a) Pectoral
b) Central
c) Lateral
d) Apical

Answer: Apical
Explanation:
The nodes of the apical or infra-clavicular group lie deep to the clavi-pectoral fascia, along the axillary vessels. They receive lymph from the central group, from the upper part of the breast, and from the thumb and its web. The lymphatics from the thumb accompany the cephalic vein.

Q-29. Axillary sheath is derived from
a) Pre-vertebral fascia
b) Clavipectoral fascia
c) Deep layer of cervical fascia
d) Pre-tracheal fascia

Answer: Pre-vertebral fascia
Explanation:
The axillary sheath is derived from the pre-vertebral layer of the deep cervical fascia. It encloses the axillary artery and the brachial plexus.