Intermediate Extensor Pollicis Longus Quiz

Q1. Through which dorsal extensor compartment does the extensor pollicis longus tendon pass at the wrist?

• Third compartment
• Sixth compartment
• Fourth compartment
• First compartment

Q2. Which bony landmark acts as a pulley for the extensor pollicis longus tendon?

• Lister's tubercle
• Ulnar styloid process
• Radial tuberosity
• Medial epicondyle

Q3. What happens to the course of the extensor pollicis longus tendon at Lister's tubercle?

• It enters the carpal tunnel
• It joins the flexor pollicis longus tendon
• It inserts immediately onto the radius
• It changes direction and courses obliquely toward the thumb

Q4. Extensor pollicis longus forms which boundary of the anatomical snuffbox?

• Lateral boundary
• Floor
• Roof
• Medial boundary

Q5. Which tendons form the opposite boundary of the anatomical snuffbox from extensor pollicis longus?

• Extensor carpi ulnaris and extensor digiti minimi
• Abductor pollicis longus and extensor pollicis brevis
• Extensor digitorum and extensor indicis
• Flexor pollicis longus and flexor pollicis brevis

Q6. Which artery traverses the floor of the anatomical snuffbox?

• Brachial artery
• Common interosseous artery
• Ulnar artery
• Radial artery

Q7. Which spinal nerve roots are commonly associated with the motor supply of extensor pollicis longus?

• C7 and C8
• C5 only
• T1 and T2
• C3 and C4

Q8. Which action best distinguishes extensor pollicis longus from extensor pollicis brevis?

• Direct extension of the thumb interphalangeal joint
• Flexion of the wrist
• Flexion of the thumb interphalangeal joint
• Opposition of the thumb

Q9. How can extensor pollicis longus function be assessed clinically?

• Resisted flexion of the thumb at the interphalangeal joint
• Resisted thumb opposition
• Resisted flexion of the index finger
• Resisted extension of the thumb at the interphalangeal joint

Q10. Which feature best distinguishes the insertion of extensor pollicis longus from that of extensor pollicis brevis?

• It inserts on the fifth metacarpal rather than the thumb
• It inserts on the distal radius rather than the thumb
• It inserts on the distal rather than proximal phalanx
• It inserts on the pisiform rather than a phalanx