Hand and forearm injury + upper limb injury

A 25-year-old male presents to the emergency department after falling off his bicycle. He complains of pain in his wrist. On examination, there is swelling and tenderness over the anatomical snuffbox. What is the most likely diagnosis?

• Scaphoid fracture

• Colles' fracture

• Radial head fracture

• Distal radius fracture

• Hamate fracture

Answer explanation

Pain and tenderness in the anatomical snuffbox are highly suggestive of a scaphoid fracture. This is a common injury following a fall on an outstretched hand. Early diagnosis is crucial due to the scaphoid's poor blood supply and risk of avascular necrosis.

A 45-year-old woman presents with numbness and tingling in her thumb, index, and middle fingers. She reports worsening symptoms at night and during activities that involve repetitive wrist flexion. What is the most likely diagnosis?

• De Quervain's tenosynovitis

• Carpal tunnel syndrome

• Cubital tunnel syndrome

• Thoracic outlet syndrome

• Radial nerve palsy

Answer explanation

The symptoms described (nocturnal paraesthesia, numbness in the thumb, index, and middle fingers, exacerbated by wrist flexion) are classic for carpal tunnel syndrome. This condition involves compression of the median nerve at the wrist.

A 30-year-old man sustains a deep laceration to his forearm. On examination, he has weakness in wrist extension and finger extension. Which nerve is most likely injured?

• Median nerve

• Ulnar nerve

• Radial nerve

• Axillary nerve

• Musculocutaneous nerve

Answer explanation

The radial nerve innervates the muscles responsible for wrist and finger extension. Injury to this nerve, particularly in the forearm, will result in weakness in these movements.

A patient presents with a suspected scaphoid fracture. Which of the following imaging modalities is MOST sensitive for early diagnosis?

• Plain X-ray

• CT scan

• MRI scan

• Ultrasound

• Bone scan

Answer explanation

While plain X-rays are the initial investigation for suspected fractures, they can miss scaphoid fractures in the early stages. MRI is the most sensitive imaging modality for detecting early scaphoid fractures, as it can visualize bone marrow edema and occult fractures.

A patient presents with pain and swelling over the medial aspect of the elbow after a fall. Which structure is most likely injured?

• Lateral epicondyle

• Medial epicondyle

• Olecranon process

• Radial head

• Ulnar nerve

Answer explanation

The medial epicondyle is located on the inner side of the elbow and is a common site of injury, especially in falls. It's also the attachment site for the wrist flexor muscles, so injury can cause pain with wrist flexion.

A patient presents with a claw hand deformity. Which nerve is most likely affected?

• Median nerve

• Ulnar nerve

• Radial nerve

• Axillary nerve

• Musculocutaneous nerve

Answer explanation

A claw hand deformity, characterized by hyperextension of the metacarpophalangeal joints and flexion of the interphalangeal joints of the ring and little fingers, is a classic sign of ulnar nerve injury. This occurs due to paralysis of the intrinsic hand muscles supplied by the ulnar nerve.

A patient with a distal radius fracture develops severe pain, swelling, and pale fingers after cast application. What is the most likely diagnosis?

• Complex regional pain syndrome

• Carpal tunnel syndrome

• Malunion

• Compartment syndrome

• Non-union

Answer explanation

Compartment syndrome is a serious condition that occurs when pressure within a muscle compartment increases, compromising blood supply to the muscles and nerves. The symptoms described (severe pain, swelling, pale fingers) are classic signs of compartment syndrome. This is a surgical emergency requiring immediate fasciotomy to relieve the pressure.

A 35-year-old woman presents with gradual onset of pain and weakness in her thumb and index finger. She reports difficulty with tasks such as buttoning her clothes and opening jars. On examination, there is weakness in thumb opposition and abduction. Which nerve is MOST likely involved?

• Radial nerve

• Ulnar nerve

• Median nerve

• Axillary nerve

• Musculocutaneous nerve

Answer explanation

The median nerve innervates the thenar muscles (including the opponens pollicis and abductor pollicis brevis), which are responsible for thumb opposition and abduction. Weakness in these movements suggests median nerve involvement, likely at the carpal tunnel (carpal tunnel syndrome).

A patient presents with pain and tenderness over the lateral epicondyle of the humerus. Which of the following is the MOST likely diagnosis?

• Medial epicondylitis

• Olecranon bursitis

• Radial head fracture

• Tennis elbow

• Ulnar nerve entrapment

Answer explanation

Lateral epicondylitis, commonly known as tennis elbow, is characterized by pain and tenderness over the lateral epicondyle of the humerus. It's an overuse injury affecting the tendons that attach to the lateral epicondyle, primarily the wrist extensors.

A patient presents with a hand injury. On examination, he has weakness in thumb abduction, but normal sensation. Which of the following structures is MOST likely injured?

• Median nerve

• Ulnar nerve

• Radial nerve (posterior interosseous branch)

• Abductor pollicis longus tendon

• First dorsal interosseous muscle

Answer explanation

While the median nerve innervates the abductor pollicis brevis, the abductor pollicis longus muscle, responsible for thumb abduction, is innervated by the posterior interosseous branch of the radial nerve. However, it's the tendon of the abductor pollicis longus that's most commonly injured in this scenario, causing weakness in thumb abduction.