CASE BASED QUESTIONS FOR PRACTICE
AND PREPRATION OF ANATOMY
, 1. Case: Eye Movement Disorder
Question:
A 45-year-old patient presents with double vision and difficulty moving the eye upward.
On examination, the affected eye is slightly down and out. Which cranial nerve is most
likely affected?
A. Trochlear nerve (CN IV)
B. Oculomotor nerve (CN III)
C. Abducens nerve (CN VI)
D. Optic nerve (CN II)
Answer: B. Oculomotor nerve (CN III)
Explanation:
The oculomotor nerve innervates most of the extraocular muscles, including the
superior rectus, inferior rectus, medial rectus, and inferior oblique.
In CN III palsy, the unopposed action of the lateral rectus (CN VI) and superior oblique
(CN IV) causes the affected eye to deviate down and out.
Diplopia (double vision) results from impaired eye alignment, and the patient may also
show ptosis (drooping of the eyelid) due to paralysis of the levator palpebrae superioris.
, 2. Case: Wrist Drop after Humeral Fracture
Question:
A 30-year-old male falls on an outstretched arm and fractures his midshaft humerus.
Following the injury, he develops wrist drop. Which nerve is most likely injured?
A. Median nerve
B. Ulnar nerve
C. Radial nerve
D. Axillary nerve
Answer: C. Radial nerve
Explanation:
The radial nerve runs along the radial groove of the humerus. Midshaft fractures can
damage this nerve, leading to wrist drop due to paralysis of the extensor muscles of the
forearm.
Patients with radial nerve injury cannot extend the wrist and fingers. Sensory loss may
also occur on the dorsal surface of the hand.
3. Case: Inability to Lift Arm Above Shoulder
, Question:
A 40-year-old woman presents with difficulty in lifting her arm above her head after an
injury. On examination, there is wasting of the deltoid muscle. Which nerve is most
likely damaged?
A. Axillary nerve
B. Suprascapular nerve
C. Musculocutaneous nerve
D. Long thoracic nerve
Answer: A. Axillary nerve
Explanation:
The axillary nerve innervates the deltoid and teres minor muscles. It is commonly
injured in anterior shoulder dislocations.
Damage to the axillary nerve leads to weakness in arm abduction beyond 15 degrees
and atrophy of the deltoid muscle. Sensory loss may occur over the “regimental badge”
area on the lateral shoulder.
4. Case: Winged Scapula
Question:
A 25-year-old athlete presents with a winged scapula after blunt trauma to the chest
wall. Which of the following nerves is most likely injured?
AND PREPRATION OF ANATOMY
, 1. Case: Eye Movement Disorder
Question:
A 45-year-old patient presents with double vision and difficulty moving the eye upward.
On examination, the affected eye is slightly down and out. Which cranial nerve is most
likely affected?
A. Trochlear nerve (CN IV)
B. Oculomotor nerve (CN III)
C. Abducens nerve (CN VI)
D. Optic nerve (CN II)
Answer: B. Oculomotor nerve (CN III)
Explanation:
The oculomotor nerve innervates most of the extraocular muscles, including the
superior rectus, inferior rectus, medial rectus, and inferior oblique.
In CN III palsy, the unopposed action of the lateral rectus (CN VI) and superior oblique
(CN IV) causes the affected eye to deviate down and out.
Diplopia (double vision) results from impaired eye alignment, and the patient may also
show ptosis (drooping of the eyelid) due to paralysis of the levator palpebrae superioris.
, 2. Case: Wrist Drop after Humeral Fracture
Question:
A 30-year-old male falls on an outstretched arm and fractures his midshaft humerus.
Following the injury, he develops wrist drop. Which nerve is most likely injured?
A. Median nerve
B. Ulnar nerve
C. Radial nerve
D. Axillary nerve
Answer: C. Radial nerve
Explanation:
The radial nerve runs along the radial groove of the humerus. Midshaft fractures can
damage this nerve, leading to wrist drop due to paralysis of the extensor muscles of the
forearm.
Patients with radial nerve injury cannot extend the wrist and fingers. Sensory loss may
also occur on the dorsal surface of the hand.
3. Case: Inability to Lift Arm Above Shoulder
, Question:
A 40-year-old woman presents with difficulty in lifting her arm above her head after an
injury. On examination, there is wasting of the deltoid muscle. Which nerve is most
likely damaged?
A. Axillary nerve
B. Suprascapular nerve
C. Musculocutaneous nerve
D. Long thoracic nerve
Answer: A. Axillary nerve
Explanation:
The axillary nerve innervates the deltoid and teres minor muscles. It is commonly
injured in anterior shoulder dislocations.
Damage to the axillary nerve leads to weakness in arm abduction beyond 15 degrees
and atrophy of the deltoid muscle. Sensory loss may occur over the “regimental badge”
area on the lateral shoulder.
4. Case: Winged Scapula
Question:
A 25-year-old athlete presents with a winged scapula after blunt trauma to the chest
wall. Which of the following nerves is most likely injured?
