Human anatomy > Muscular System > Neck Muscles The neck is the part of the human body that attaches the head to the rest of the body. It is made up of many muscles that are connected from the head to the torso of the body.
About.com Chemistry states that rigor mortis can take anywhere between 10 minutes to several hours to set in. Rigor mortis is the time after death when a body begins to stiffen, and the joints lock into place. Continue Reading.
The muscles then stiffen, perhaps due to coagulation of muscle proteins or a shift in the muscle's energy containers (ATP-ADP), into a condition known as rigor mortis. All of the body's muscles are affected. Rigor mortis begins within two to six hours of death, starting with the eyelids, neck, and jaw. This sequence may be due to the difference in lactic acid levels among different muscles, which corresponds to the difference in glycogen levels and to the different types of muscle fibers.