Healthy hands Coloured Xray of healthy human hands Bone is pink with tissue yellow and blue Each hand has one thumb and four fingers consisting of two and three phalanges bones respectively The palms are formed by the metacarpal bones with the carpal bones of the wrists lower left and right below them The bones of the forearm the radius larger and the ulna are at bottom right and left A thumb which opposes the other fingers is only found in humans and other primates It gives the hand precise and delicate movement