<prompt> Ape hand deformity is due to damage to which nerve?Radial nerveUlnar nerveMedian nerveNone  <response>: ANSWER: C Median nerveREF-. Grays anatomy 39th edition page 933See APPENDIX-7 below for BRACHIAL PLEXUS LESIONSAs per Grays A combined median and ulnar nerve palsy at the wrist results in a full claw hand with thenar and hypothenar flattening, and thumb adduction and flexion. This posture is known as a simian hand because of the similarity to the appearance of the hand of an apeBut even median nerve palsy alone can cause ape hand deformity APPENDIX - 7Brachial Plexus Lesions-chart 1Nerve SegmentMotor DeficitsSensory DeficitsLong Thoracic C 5, 6, 7Winged Scapula- Serratus AnteriorNoneSuprascapular C 5, 6 Hard to start shoulder abduction - SupraspinatusNoneAxillary C 5, 6 Difficult abducting arm to horizontal - DeltoidLateral side of arm below point of shoulder Loss of shoulder roundness - DeltoidMusculocutaneous C 5, 6, 7Very weak flexion of elbow joint- Biceps BrachialisLateral forearm Weak supination of radioulnar joint -Biceps Radial C 5 - TlDrop Wrist - Extensor carpi radialis iongus brevis, Ext. carpi ulnarisPosterior lateral arm; dorsum of hand Difficulty making a fist - synergy between wrist 1 extensors and finger flexors Median EUR 5 - Tl at ElbowPronation of radioulnar joints-Pronator teres quadratusRadial portion of palm; palmar surface 8i tips of radial 3 Weak wrist flexion - FI. carpi radialisdigits Weakened opposition of thumb - thenar muscles Ape Hand- thumb hyper extended and adducted - thenar muscles Papal Hand Loss of flexion of I.P. joints of thumb fingers 1 2 - Fl. pollices Iongus ; FL digit, superficialis, FL digit profundus Median C 5 - Tl at WristWeakened opposition of thumb - thenar musclesPalmar surface tips of radial Ape Hand- thumb hyper extended and adducted - thenar muscles3 digitsUlnar C 8, Tl at ElbowClawing of fingers 3 4- M.P. joints hyper extended: P.I.P. Flexed - Interossei LumbricalsUlnar and dorsal aspect of palm and of ulnar VA digits Loss of abduction adduction of M.P joints of fingers -Interossei Thumb - abducted and extended - adductor pollices Loss of flexion of D.I.P. joints of fingers 4 8t 5 - Fl. digit profund. Ulnar C 8, Tl at WristClawing of fingers 3 4- M.P. joints hyper extended; P.I.P. Flexed - Interossei LumbricalsUlnar and dorsal aspect of palm and of ulnar 1 xk digitsLoss of abduction adduction of M.P joints of fingers - InterosseiThumb - abducted and extended - adductor pollicesUpper and Lower Root Lesions-chart 2LesionMotor DeficitsSensory DeficitsNervesErb s PalsyC5,6Loss of abduction, flexion and rotation at shoulder; Weak shoulder extension - deltoid, rotator cuffPosterior and lateral aspect of arm - axillary n.Axillary, Suprascapular, Upper and Lower subscapular Very weak elbow flexion and supination of radioulnar joint - biceps brachii brachiaiisRadial side of Forearm- musculocutaneous n. Thumb and 1st finger - superficial hr. of radial; digital brs. - Median n.Musculocutaneous: Radial N. brs. to supinator brachioradialis muscles Susceptible to shoulder dislocation - loss of rotator cuff muscles Suprascapular, Upper and Lower subscapular Waiters Tip position Klumkes Palsy C8, TlLoss of opposition of thumb -Tnenar musclesUlnar side of forearm, hand ulnar 1 Vi digits - ulnar and medial antebrachial cutaneousThenar branch of Median nerve Loss of adduction of thumb - Adductor pollices Ulnar nerve Loss of following finger movements: abduction and adduction of M.P. joints; flexion at M.P. extension of LP. joints. Lumbricals interossei Deep branch of Ulnar Median Very weak flexion of P.I.P. D.I.P. joints FI Digit. Super. Profund. Ulnar and Median 