It has no known function and can be cut without apparent consequence.[2]
【 Structure 】A study upon the arms of 38 people found that its mean length is 3.4 cm (range 2.4 to 4.2 cm) and in most people it tapers(先細りする) from the ulna to the radius end, being at the ulna 9 mm, in its middle, 7mm and its radius end 4 mm.[2]」