Limbs 4 – Hand Anil Chopra 1. 2. 3. 4. 5.
Name the bones and joints of the wrist and hand Name and demonstrate the movements of the wrist and hand Distinguish between the power and precision grips Outline the main neuromuscular mechanisms underlying each type of grip Summarise in simple terms the overall pattern of motor and sensory segmental nerve distribution to the limb 6. Explain (in principle only) the role of the brachial plexus 7. Explain the main motor and sensory deficits associated with carpal tunnel syndrome, ulnar nerve injury near the elbow, radial nerve injury in the spiral groove, injury to the lower segments of the brachial plexus 8. Outline the functional deficits caused by the common injuries of the flexor and extensor tendons 9. Outline the mallet finger deformity 10. Identify and summarise the functions of the carpal bones 11. Describe how fractures of the scaphoid occur and explain why such injuries are important 12. Discuss the clinical term, trigger finger 13. Describe gamekeeper’s thumb (skier’s thumb) and its anatomical basis. Bones of the Region The Carpel Bones: • Proximal row (lateral to medial)= Scaphoid – forms the wrist joint Lunate – forms the wrist joint Triquetrum – forms the wrist joint Pisiform – a sesimoid bone (develops in the tendon when it rubs forming a synovial joint (also seen in patella) is formed from FCU (flexor carpi ulnaris) • Distal row (lateral to medial) = Trapezium – supports the thumb by forming a saddle joint with it Trapezoid – supports the index finger Capitate – supports the middle finger. Acts like a keystone in supporting the carpus Hamate – supports the ring and little finger • The radius articulates with the scaphoid, lunate and triquetrum to form the wrist joint • The ulna does not articulate with the carpus except via the triangular fibrocartilage which extends from the distal radius to ulna • The scaphoid has a clinically important blood supply – blood vessels tend to pass from distal to proximal but can be interrupted by a fracture of the waist of the bone causing the proximal end to undergo avascular necrosis Metacarpals: 5 metacarpals, (the thumb is number I) consisting of a base, shaft and head.