You receive a humerus for “distal shaft mass assessment”.  T…

You receive a humerus for “distal shaft mass assessment”.  The patient’s chart shows an x-ray in which the mass appears to be diffusely spread. The patient’s forearm was previously disarticulated with a diagnosis of osteosarcoma. Based on this, you expect to find all of the following osseous markings and landmarks with mass involvement, EXCEPT: