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An ulnar claw, also known as claw hand, or 'Spinster's Claw' is an abnormal hand position that develops due to a problem with the ulnar nerve. A hand in ulnar claw position will have the 4th and 5th fingers drawn towards the back of the hand at the first knuckle and curled towards the palm at the second and third knuckles. Some sources incorrectly refer to the ulnar claw as a "hand of benediction"〔http://www.tabers.com/tabersonline/ub/view/Tabers/143428/26/benediction_hand〕 or "pope's blessing". However, the term "hand of benediction" or "pope's blessing" more commonly refers to a similar hand position which is caused by damage to the median nerve〔http://cpmcnet.columbia.edu/student/ssn/anatomy/brachial_plexus.pdf〕〔http://cme.medscape.com/viewarticle/527751_8〕 and is only present when the patient is asked to make a fist.〔 == Presentation == The hand will show hyper-extension of the metacarpophalangeal joints (MCP) and flexion of the distal and proximal Interphalangeal (IP) joints of the 4th and 5th digits (ring and little finger).〔(Wheeless' Textbook of Orthopaedics - Ulnar Nerve )〕 The clawing will become most obvious when the person is asked to flex the digits from an extended position as the 4th and 5th digits can not flex due to the injury to the ulnar nerve. 1st, 2nd and 3rd digits will partially flex giving them a "claw-like" appearance, this happens because the Thenar muscles (Abductor pollicis brevis, Flexor Pollicis brevis and Opponens pollicis) are innervated by the median nerve as the first two lumbricals of digit 2 and 3 are. (The image relates to hand of papal benediction due to damage to median nerve) Patients exhibiting an ulnar claw are also very frequently unable to spread (abduct) or pull together (adduct) the fingers against resistance. This occurs because the ulnar nerve also innervates the palmar and dorsal interossei of the hand. Patients with this deficit will become increasingly easy to identify over time as the paralyzed first dorsal interosseous muscle atrophies, leaving a prominent hollowing between the thumb and forefinger. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「ulnar claw」の詳細全文を読む スポンサード リンク
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