hindlimb muscle morphology trait quadriceps morphology trait 2013-10-07T11:15:20Z Any measurable or observable characteristic related to the shape, structure, color, or pattern of the group of four muscles (rectus femoris, vastus intermedius, vastus lteralis, and vastus medialis) which extend down the front of the thigh and are the major extensors of the knee joint. Trait.ontology VT:0010569 caripark