Upper Limb Practice Questions

Q: Which nerve is closely related to the shoulder joint capsule?

Axillary nerve. ### Explanation **Correct Answer: D. Axillary Nerve** The **axillary nerve (C5, C6)** is the correct answer because of its intimate anatomical relationship with the inferior aspect of the shoulder joint capsule. After originating from the posterior cord of the brachial plexus, the axillary nerve passes through the **quadrangular space** and winds around the **surgical neck of the humerus**. At this point, it lies directly inferior to the glenohumeral joint capsule. This proximity makes it highly vulnerable to injury during **inferior dislocations** of the shoulder or fractures of the surgical neck of the humerus. **Analysis of Incorrect Options:** * **A. Radial Nerve:** While it also arises from the posterior cord, it passes inferior to the teres major to enter the radial groove on the posterior shaft of the humerus, distal to the joint capsule. * **B. Ulnar Nerve:** This nerve runs medially in the arm and is most clinically related to the medial epicondyle of the humerus, far from the shoulder capsule. * **C. Subscapular Nerve:** The upper and lower subscapular nerves supply the subscapularis and teres major muscles. While they are in the vicinity of the anterior axilla, they do not wrap around the joint capsule like the axillary nerve. **Clinical Pearls for NEET-PG:** * **Hilton’s Law:** The axillary nerve supplies the shoulder joint, the deltoid, and the teres minor. According to Hilton’s Law, a nerve supplying a joint also supplies the muscles moving that joint and the skin over it. * **Regimental Badge Area:** Injury to the axillary nerve leads to loss of sensation over the lateral aspect of the upper arm and paralysis of the deltoid (loss of abduction beyond 15°). * **Quadrangular Space Boundaries:** Superior (Teres minor), Inferior (Teres major), Medial (Long head of triceps), Lateral (Surgical neck of humerus). It contains the axillary nerve and posterior circumflex humeral artery.

Q: The third head of the coracobrachialis muscle is associated with which anatomical structure?

Struther's ligament. **Explanation:** The **coracobrachialis** muscle typically consists of two heads in humans, but embryologically it is a three-layered muscle. The **third (deep) head** is often considered a vestigial structure that, when present, may form a fibrous band known as **Struther’s ligament**. 1. **Why Option A is Correct:** Struther’s ligament is a fibrous band extending from a bony projection called the **supracondylar process** (on the anteromedial aspect of the humerus) to the medial epicondyle. It represents the remnant of the lower part of the third head of the coracobrachialis. Clinically, the **median nerve** and **brachial artery** pass beneath this ligament, making it a potential site for high median nerve compression. 2. **Why Other Options are Incorrect:** * **Brachioradialis (B):** This is a muscle of the superficial posterior compartment of the forearm, unrelated to the coracobrachialis or Struther’s ligament. * **Radial collateral ligament (C):** This is a stabilizing ligament on the lateral side of the elbow joint. * **Ulnar ligament (D):** This refers to the medial collateral ligament of the elbow; while located medially, it has no developmental association with the coracobrachialis. **High-Yield NEET-PG Pearls:** * **Nerve Supply:** Coracobrachialis is pierced by and supplied by the **Musculocutaneous nerve**. * **Struther’s Ligament vs. Arcade of Struthers:** Do not confuse them. Struther’s ligament is at the distal humerus (median nerve), while the **Arcade of Struthers** is a thin aponeurotic band in the distal third of the arm that can compress the **ulnar nerve**. * **Supracondylar Process:** Present in only ~1% of the population; its presence is a prerequisite for Struther’s ligament.

Q: The clavipectoral fascia is not pierced by which of the following structures?

Medial pectoral nerve. The **clavipectoral fascia** is a strong fascial sheet situated deep to the clavicular head of the pectoralis major. It extends from the clavicle above to the axillary fascia below. Understanding the structures that pierce this fascia is a high-yield topic for NEET-PG. ### **Why Medial Pectoral Nerve is the Correct Answer** The **Medial Pectoral Nerve** (C8, T1) arises from the medial cord of the brachial plexus. It does not pierce the clavipectoral fascia; instead, it passes **between the pectoralis minor and pectoralis major** [1] or pierces the pectoralis minor muscle itself to reach and supply the pectoralis major. ### **Analysis of Incorrect Options (Structures that DO pierce the fascia)** Four specific structures pierce the clavipectoral fascia at the level of the costocoracoid membrane. You can remember them using the mnemonic **"CALL"** or **"SALT"**: * **C**ephalic vein: Travels in the deltopectoral groove and pierces the fascia to drain into the axillary vein. * **A**cromiothoracic (Thoracoacromial) artery: A branch of the second part of the axillary artery. * **L**ateral pectoral nerve: Arises from the lateral cord and pierces the fascia to supply the pectoralis major. * **L**ymphatics: Specifically those passing from the breast and infraclavicular region to the apical group of axillary lymph nodes. ### **Clinical Pearls for NEET-PG** * **Attachments:** Superiorly, it splits to enclose the subclavius muscle; inferiorly, it splits to enclose the pectoralis minor and continues as the **suspensory ligament of the axilla**, which maintains the hollow of the armpit. * **Nerve Supply Distinction:** The *Lateral* pectoral nerve pierces the fascia, while the *Medial* pectoral nerve pierces the muscle (Pectoralis minor) or wraps around its lateral border [1]. * **Surgical Importance:** The fascia must be incised to gain access to the axillary artery during surgical procedures or to clear the Level II axillary lymph nodes.

Q: The oblique cord is related to which of the following muscles?

Flexor pollicis longus. The **oblique cord** (or chorda obliqua) is a small, flat ligamentous band that extends between the radius and the ulna. It originates from the lateral side of the **ulnar tuberosity** and runs downward and laterally to be inserted into the radius, just below the **radial tuberosity**. **Why Flexor Pollicis Longus (FPL) is correct:** The oblique cord lies in the same plane as the interosseous membrane but its fibers run in the opposite direction. Crucially, its lower border is continuous with the fascia covering the **Flexor pollicis longus**. In many individuals, the FPL takes a partial origin from the oblique cord itself. **Analysis of Incorrect Options:** * **A. Supinator:** The supinator muscle is located more superiorly and posteriorly in the forearm. While it relates to the radial tuberosity, it does not have a direct structural continuity with the oblique cord. * **C. Flexor digitorum profundus (FDP):** The FDP originates primarily from the anterior and medial surfaces of the ulna and the interosseous membrane, but it is medial to the site of the oblique cord. * **D. Flexor digitorum superficialis (FDS):** The FDS has a broad origin (humeroulnar and radial heads), but its radial head originates from the anterior oblique line of the radius, distal to the insertion of the oblique cord. **High-Yield Facts for NEET-PG:** * **Fiber Direction:** The fibers of the oblique cord run **downwards and laterally**, whereas the fibers of the interosseous membrane run **downwards and medially**. * **Gap:** There is a gap between the upper border of the interosseous membrane and the oblique cord through which the **posterior interosseous vessels** pass. * **Function:** It acts as a tie-beam to prevent displacement of the radius during forceful movements, though its functional significance is considered minimal compared to the interosseous membrane.

Q: A 21-year-old woman presents with shoulder and arm injury after a fall during horseback riding. Examination reveals inability to adduct her arm due to paralysis of which of the following muscles?

Latissimus dorsi. ### Explanation **Correct Option: C. Latissimus dorsi** The **Latissimus dorsi** is a powerful muscle of the posterior axillary wall. Its primary actions are **adduction, extension, and medial rotation** of the humerus (often remembered by the mnemonic "The Lady between two Majors"—it inserts into the floor of the bicipital groove between the Pectoralis major and Teres major). In the context of a shoulder injury, paralysis of this muscle significantly impairs the ability to pull the arm toward the midline (adduction) against resistance. **Analysis of Incorrect Options:** * **A. Teres minor:** This muscle is part of the rotator cuff. Its primary action is **lateral rotation** of the arm and stabilization of the glenohumeral joint. * **B. Supraspinatus:** This rotator cuff muscle is responsible for the **initiation of abduction** (first 0–15 degrees). It does not contribute to adduction. * **C. Infraspinatus:** Similar to the Teres minor, this muscle acts as a powerful **lateral rotator** of the arm. **Clinical Pearls for NEET-PG:** * **Nerve Supply:** Latissimus dorsi is supplied by the **Thoracodorsal nerve** (C6, C7, C8), a branch of the posterior cord of the brachial plexus. * **Clinical Testing:** To test the Latissimus dorsi, the patient is asked to adduct the elevated arm against resistance or to cough (it is an accessory muscle of expiration, hence the "Climbing muscle" or "Coughing muscle"). * **Surgical Significance:** The Latissimus dorsi flap is commonly used in reconstructive surgeries, such as breast reconstruction. * **Injury Association:** Damage to the thoracodorsal nerve often occurs during axillary lymph node dissection or surgeries in the inferior part of the axilla.

Q: Which nerve runs along with the profunda brachii artery in the spiral groove?

Radial. **Explanation:** The **Radial nerve** is the correct answer because of its specific anatomical course in the posterior compartment of the arm. After originating from the posterior cord of the brachial plexus, the radial nerve enters the **spiral (radial) groove** on the posterior surface of the humerus. It is accompanied here by the **profunda brachii artery** (deep artery of the arm). This neurovascular bundle lies directly against the bone, making it highly vulnerable to injury in mid-shaft fractures of the humerus. **Analysis of Incorrect Options:** * **Ulnar Nerve:** Runs in the medial compartment and passes behind the medial epicondyle of the humerus (cubital tunnel), not the spiral groove. It is accompanied by the superior ulnar collateral artery. * **Median Nerve:** Descends in the anterior compartment of the arm within the medial bicipital groove, lateral to the brachial artery initially, then crossing to its medial side. It has no relation to the spiral groove. * **Musculocutaneous Nerve:** Pierces the coracobrachialis muscle and travels between the biceps brachii and brachialis muscles in the anterior compartment. **High-Yield Clinical Pearls for NEET-PG:** * **Fracture Correlation:** Mid-shaft humerus fractures commonly injure the radial nerve in the spiral groove, leading to **"Wrist Drop"** due to paralysis of the extensors of the wrist and digits. * **Saturday Night Palsy:** Compression of the radial nerve in the spiral groove (e.g., hanging an arm over a chair) leads to temporary loss of function. * **Triangular Space:** The profunda brachii artery and radial nerve enter the posterior compartment via the **lower triangular space** (bounded by teres major, long head of triceps, and humerus).

Q: Erb's palsy involves which nerve roots?

C5, C6. **Explanation:** **1. Why C5 and C6 are correct:** Erb’s palsy (Upper Brachial Plexus Injury) results from damage to the **upper trunk** of the brachial plexus, which is formed by the union of the **C5 and C6 nerve roots**. This injury typically occurs due to an excessive increase in the angle between the neck and the shoulder (e.g., birth trauma during difficult labor or a fall on the shoulder) [1]. The site of injury is known as **Erb’s point**, where six nerves meet. **2. Why other options are incorrect:** * **C8, T1 (Option B):** These roots form the lower trunk. Injury here leads to **Klumpke’s palsy**, characterized by a "claw hand" due to the involvement of intrinsic hand muscles. * **T1, T2 (Option C):** T2 is not a primary component of the brachial plexus (which spans C5-T1). T1 is involved in Klumpke’s, but T2 primarily contributes to the intercostobrachial nerve. * **C6, C7 (Option D):** While C6 is involved in the upper trunk, C7 forms the middle trunk in isolation. Isolated middle trunk injuries are clinically rare. **3. Clinical Pearls for NEET-PG:** * **Deformity:** The classic presentation is the **"Policeman’s tip hand"** or **"Waiter’s tip hand."** * **Position of the limb:** The arm is **Adducted** (loss of abductors), **Medially rotated** (loss of lateral rotators), and the forearm is **Extended** (loss of biceps) and **Pronated** (loss of supinator). * **Muscles paralyzed:** Mainly Biceps brachii, Deltoid, Brachialis, and Brachioradialis (partially Supraspinatus and Infraspinatus) [1]. * **Reflexes:** The Biceps and Supinator reflexes are lost.

Q: Which of the following is NOT a function of the Latissimus Dorsi muscle?

External rotation of the shoulder. **Explanation:** The **Latissimus Dorsi** (often called the "Climber's Muscle") is a large, fan-shaped muscle of the back. To understand its functions, one must look at its insertion: it attaches to the **floor of the bicipital groove** (intertubercular sulcus) of the humerus. **1. Why "External Rotation" is the correct answer:** Because the Latissimus Dorsi inserts on the **anterior** aspect of the humerus (the bicipital groove) after wrapping around from the back, its contraction pulls the humerus medially. Therefore, it acts as a **medial (internal) rotator**, not an external rotator. External rotation is primarily performed by the Infraspinatus and Teres Minor. **2. Analysis of incorrect options:** * **Extension (Option B):** As it originates from the posterior trunk (T7-L5 vertebrae, iliac crest, and thoracolumbar fascia) and pulls the humerus backward, it is a powerful extensor of the flexed arm. * **Adduction (Option C):** Its fibers pull the humerus toward the midline of the body, making it a primary adductor of the shoulder. * **Medial Rotation (Option D):** As explained above, its anterior insertion point allows it to rotate the humerus inward. **High-Yield NEET-PG Pearls:** * **Mnemonic for Bicipital Groove:** "A Lady between two Majors." The **L**atissimus dorsi (Lady) inserts into the floor, while the Pectoralis **Major** and Teres **Major** insert into the lateral and medial lips, respectively. * **Nerve Supply:** Thoracodorsal nerve (C6, **C7**, C8), a branch of the posterior cord of the brachial plexus [1]. * **Clinical Significance:** It is commonly used as a pedicled flap in reconstructive breast surgery (Latissimus Dorsi Flap) [2]. * **Functional Role:** It is crucial for activities like swimming, rowing, and climbing.

Question 1

Which nerve is closely related to the shoulder joint capsule?

Accepted Answer

Axillary nerve

Answer

Radial nerve

Answer

Ulnar nerve

Answer

Subscapular nerve

Question 2

The third head of the coracobrachialis muscle is associated with which anatomical structure?

Accepted Answer

Struther's ligament

Answer

Brachioradialis

Answer

Radial collateral ligament

Answer

Ulnar ligament

Question 3

The clavipectoral fascia is not pierced by which of the following structures?

Accepted Answer

Medial pectoral nerve

Answer

Lateral pectoral nerve

Answer

Cephalic vein

Answer

Thoracoacromial artery

Question 4

The oblique cord is related to which of the following muscles?

Accepted Answer

Flexor pollicis longus

Answer

Supinator

Answer

Flexor digitorum profundus

Answer

Flexor digitorum superficialis

Question 5

Loss of sensation in the lateral 3 and 1/2 fingers is indicative of injury to which nerve(s)?

Accepted Answer

Median nerve and radial nerve

Answer

Only median nerve

Answer

Median nerve and ulnar nerve

Answer

Ulnar and radial nerve

Question 6

A 21-year-old woman presents with shoulder and arm injury after a fall during horseback riding. Examination reveals inability to adduct her arm due to paralysis of which of the following muscles?

Accepted Answer

Latissimus dorsi

Answer

Teres minor

Answer

Supraspinatus

Answer

Infraspinatus

Question 7

Which nerve runs along with the profunda brachii artery in the spiral groove?

Accepted Answer

Radial

Answer

Ulnar

Answer

Median

Answer

Musculocutaneous nerve

Question 8

Which of the following structures is present in the lateral wall of the axilla?

Accepted Answer

Axillary vessels

Answer

Subscapular vessel

Answer

Brachial plexus

Answer

Long thoracic nerve

Question 9

Erb's palsy involves which nerve roots?

Accepted Answer

C5, C6

Answer

C8, T1

Answer

T1, T2

Answer

C6, C7

Question 10

Which of the following is NOT a function of the Latissimus Dorsi muscle?

Accepted Answer

External rotation of the shoulder

Answer

Extension of the shoulder

Answer

Adduction of the shoulder

Answer

Medial rotation of the shoulder

Upper Limb — MCQs

Upper Limb — MCQs

On this page

Practice by Chapter

Want unlimited practice?