Flashcards in The Hand Deck (10):
What is the most common carpal injury?
How can Avascular Necrosis occur in this injury?
Fracture across the waist of the Scaphoid bone.
10% of people's scaphoid is supplied blood from the distal end of the bone only. The fracture can disrupt this blood supply creating avascular necrosis.
Carpal tunnel syndrome...How does the increased pressure from overuse, swelling of tendons and sheaths , and cysts affect the nerves?
Increased pressure in the capal tunnel is thought to cause venous congestion that produces nerve edema and anoxic damage to the capillary endothelium of the median nerve itself.
What is the treatment for Carpal Tunnel?
Reduce inflammation and remove and repetitive stressors that produce symptoms.
If that doesn't work, nerve conduction studies are done to find nerve entrapment areas which may need surgical decompression of the flexor retinaculum.
What are the 2 reasons doctors use the anatomical snuffbox for besides locating 3 muscles?
When ulnarly rotated, the scaphoid becomes palpable in the snuffbox, which is necessary to palpate for a fracture.
The pulse of the radial artery can also be felt in the snuffbox.
What is De Quervain's syndrome?
Inflammation disorder of the extensor pollicis brevis tendon and the abductor pollicis longus tendon and their common tendon sheath. Patients have significant wrist pain that prevents flexion/extension, and abduction of the thumb. Caused by overuse, often lifting babies. Also caused by rheumatoid arthritis.
What is Tenosynovitis?
Inflammation of a tendon and its sheath.
Caused by overuse, rheumatoid arthritis, or connective tissue pathologies.
Tendon doesn't run through the sheath smoothly and may require extra force to fully extend and flex causing "triggering".
What is Trigger Finger?
The flexor tendon sheath gets caught in the metacarpophalangeal joint due to fibrosis and tightening of the flexor tendon sheath.
Characterized by snapping and occasional locking of flexor tendon in the hand.
Happens in late childhood and adulthood.
What are the 3 components of the Extensor Expansion and how do they connect?
Lateral bands---attach to base of distal phalanx.
Middle slip--attaches to base of middle phalanx.
Hood of extensor expansion--attaches to sides of base of proximal phalanx and transverse M.C. Ligament.
What intrinsic muscles attach to the extensor hood in digits 2-5?
Lumbricals, Interossei and abductor digiti minimi.