Ape thumb deformity is seen in involvement of -

Ape thumb deformity : in this the thumb is in the same plane as the wrist .It occurs due to paralysis of opponens pollicis muscle in median nerve injury at the wrist & the unopposed action of extensor pollicis longus produces an ape like hand .The thenar eminence is wasted & flattened .The thumb is adducted & laterally rotated so that the first metacarpal lies in same plane other metacarpals. REF:Essential ohopedics ,Maheshwari ,5th edition , pg.no.64