Advanced Anterior Compartment of the Forearm Quiz

Q1. A patient cannot form a normal tip-to-tip pinch between the thumb and index finger because flexion of their distal phalanges is weak. Which nerve is most likely affected?

• Axillary nerve
• Superficial radial nerve
• Anterior interosseous nerve
• Posterior interosseous nerve

Q2. Why can anterior interosseous nerve syndrome produce motor deficits without a cutaneous sensory deficit?

• It supplies only the skin of the palm
• The anterior interosseous nerve has no cutaneous sensory distribution
• It is a branch of the radial artery rather than a nerve
• It contains only sympathetic fibers

Q3. Compression of the median nerve between the heads of pronator teres may produce which syndrome?

• Pronator syndrome
• Quadrangular space syndrome
• Radial tunnel syndrome
• Cubital tunnel syndrome

Q4. A proximal ulnar nerve lesion would weaken which anterior forearm muscles?

• Flexor pollicis longus and pronator quadratus
• Flexor carpi ulnaris and the medial part of flexor digitorum profundus
• Pronator teres and flexor carpi radialis
• Palmaris longus and flexor digitorum superficialis

Q5. A patient can flex the proximal interphalangeal joint of the index finger but cannot flex its distal interphalangeal joint. Which muscle is failing to act normally?

• Flexor carpi radialis
• Flexor digitorum superficialis
• Pronator teres
• Flexor digitorum profundus

Q6. A patient cannot flex the proximal interphalangeal joint of a finger when the other fingers are held extended. Which muscle is primarily being tested?

• Pronator quadratus
• Flexor digitorum profundus
• Flexor pollicis longus
• Flexor digitorum superficialis

Q7. Which structure separates many deep anterior forearm muscles from the posterior compartment and provides a surface for muscular attachment?

• Palmar aponeurosis
• Annular ligament of the radius
• Flexor retinaculum
• Interosseous membrane

Q8. Why can severe swelling within the anterior forearm compartment threaten muscle and nerve viability?

• The fascia immediately blocks all arterial inflow after exercise
• Forearm muscles have no arterial supply
• Elevated compartment pressure can compromise tissue perfusion
• The radius and ulna normally fuse during swelling

Q9. Ischemic injury and fibrosis of the forearm flexor muscles following severe compartment syndrome can result in which deformity?

• Volkmann ischemic contracture
• Dupuytren contracture
• Mallet finger
• Boutonniere deformity

Q10. Which description best summarizes the anatomical organization of the anterior compartment of the forearm?

• It is a layered flexor-pronator compartment supplied mainly by the median nerve, with important ulnar nerve exceptions
• It contains only wrist flexors and no muscles acting on the digits
• It is supplied exclusively by the ulnar nerve and ulnar artery
• It is an extensor-supinator compartment supplied entirely by the radial nerve