Anatomy Quiz

A 22-year-old medical student is examined for shoulder function. She is unable to initiate abduction of the arm at the shoulder joint (0-15°), but abduction beyond this range is preserved when assisted. Which muscle is primarily responsible for initiating this movement?

• Deltoid

• Supraspinatus

• Infraspinatus

• Teres minor

• Subscapularis

During dissection, a student observes the articulation between the head of the humerus and the glenoid cavity. Which type of synovial joint is the shoulder joint?

• Plane

• Hinge

• Ball and socket

• Ellipsoid

• Pivot

A patient with axillary nerve injury can initiate abduction but is unable to continue it beyond 15°. Which muscle is primarily responsible for abduction up to 90°?

• Latissimus dorsi

• Teres major

• Deltoid

• Pectoralis major

• Trapezius

A tennis player raises her arm above her head. Which muscle facilitates abduction beyond 90° by rotating the scapula?

• Latissimus dorsi

• Teres major

• Serratus anterior

• Deltoid

• Coracobrachialis

A 25-year-old footballer sustains an Anterior dislocation of the shoulder joint. Which nerve is most at risk of injury?

• Suprascapular artery

• Axillary artery

• Ulnar artery

• Median artery

• Radial artery

A fracture at the surgical neck of the humerus results in weakness of abduction beyond 15°. Which nerve is most likely injured?

• Radial

• Axillary

• Musculocutaneous

• Median

• Ulnar

A 40-year-old patient undergoes ligation of the first part of the axillary artery during surgery for trauma. Collateral circulation around the scapula maintains perfusion of the upper limb through an anastomosis between branches of the subclavian and axillary arteries. Which of the following arteries is a key contributor to this scapular anastomosis?

• Profunda brachii artery

• Superior thoracic artery

• Dorsal scapular artery

• Radial recurrent artery

• Superior ulnar collateral artery

A 22-year-old man presents to the ER department after falling from a motorcycle. X-ray shows a fracture of the mid-shaft of the humerus. On examination, he has developed a wrist drop and is unable to extend his wrist and fingers. There is also loss of sensation over the dorsum of the hand. Which nerve is most likely injured?

• Ulnar nerve

• Radial nerve

• Median nerve

• Axillary nerve

• Musculocutaneous nerve

The cubital fossa is located on front of elbow and allows passage of essential nerves and blood vessels between the upper arm and forearm. Which of the following structures lies most superficially in this important anatomical area?

• Median nerve

• Radial nerve

• Brachial artery

• Median cubital vein

• Biceps tendon

A 46-year-old woman who works as a typist presents with numbness and tingling in the thumb, index finger, middle finger, and lateral half of the ring finger. She reports that symptoms worsen at night and that she often shakes her hand to relieve the discomfort. On examination, there is weakness of thumb opposition and wasting of the thenar eminence. Which nerve is most likely compressed in the carpal tunnel?

• Ulnar nerve

• Radial nerve

• Median nerve

• Musculocutaneous nerve

• Axillary nerve