<prompt> Pisiform is which type of bonePneumatic boneSesamoid boneAccessory boneLong bone  <response>: Pisiform is pea shaped and has only one oval facet on the proximal pa of its dorsal surface. Pisiform aiculates only with Triquetral . Its Ossification stas at 12 years of age . It is situated where the ulna joins the wrist, within the tendon of the flexor carpi ulnaris muscle. B D Chaurasia 7th edition Page no : 27,28,29 