abnormal hand

a.Describe the picture above

• Thumb is abducted and extended with distal phalanx flexed
• First two fingers are fully extended with a slight flexion of distal phalanges
• Medial two fingers are hyperextended at the MCP joints but flexed at the DIP joints

b.Name this condition

Claw hand

c.what nerve that cause the lesion

ulnar nerve

d.what are the muscles that innervated by this nerve

• FCU,1/2 medial FDP
• small muscle at hand
  all interossei(palmar n dorsal)
  medial 2 lumberical
  hypothenar muscles(Abd DM,FDM,ODM)
  Add pollicis
• Palmaris brevis

e.Pathogenesis of claw hand?

• ulnar nerve innervates the medial 2 of lumbricals
• function lumbrical is flexion at MCP joint and extension of both IP joints(prox n distal)
• therefore,lesion at ulnar nerve results in loss of functinal lumbrical and manifest with its opposite action

thanks to nisa=p