Inhibition of smooth tendon gliding due to mechanical impingement at the level of the A1 pulley that causes progressive pain, clicking catching and locking of the affected finger

Aetiology

• More common in females
• Typically age 50+ (but can occur at any age)
• More common in diabetics

Pathophysiology

• Tendons run within flexor tendon sheath
• Stenosing tenosynovitis (tendon swelling) → irritation → fibrocartilaginaginous metaplasia (more swelling) → nodule on FDS tendon
• The nodule results in the loss of smooth gliding of the finger flexor tendons under the annular pully, so finger gets locked in flexed position

Clinical presentation

Symptoms

• Pain over A1 pulley (MC head)
• Sticking of finger, usually in flexion
  • May need other hand to extend
  • May not be able to extend at all

Signs

• Demonstrate triggering
• Tenderness over A1 pulley
• Feel nodule pass beneath pulley
• Distinguish between Dupuytren's

Investigations