What is the term for the stiffness of death, often involving the jaw and facial muscles?

What is the term for the stiffness of death, often involving the jaw and facial muscles?

• A. Putrefaction
• B. Livor Mortis
• C. Algor Mortis
• D. Rigor Mortis

Answer: (D)

Rigor mortis is the stiffness that appears after death. It happens because the body’s cells stop producing ATP, so calcium builds up inside muscle cells and the actin and myosin filaments form cross-bridges that can’t detach. This locks the muscles in position, often starting with the small muscles of the face and jaw and then moving to the neck and larger muscle groups. The onset is influenced by temperature and other factors, typically beginning a few hours after death, peaking around midday, and gradually dissipating over the next day or two as muscles break down. To see how it differs from other postmortem changes: putrefaction is the decomposition caused by bacteria; livor mortis is the pooling of blood in dependent parts of the body that causes color changes, and algor mortis is the cooling of the body to ambient temperature.

Rigor mortis is the stiffness that appears after death. It happens because the body’s cells stop producing ATP, so calcium builds up inside muscle cells and the actin and myosin filaments form cross-bridges that can’t detach. This locks the muscles in position, often starting with the small muscles of the face and jaw and then moving to the neck and larger muscle groups. The onset is influenced by temperature and other factors, typically beginning a few hours after death, peaking around midday, and gradually dissipating over the next day or two as muscles break down.

To see how it differs from other postmortem changes: putrefaction is the decomposition caused by bacteria; livor mortis is the pooling of blood in dependent parts of the body that causes color changes, and algor mortis is the cooling of the body to ambient temperature.