Rigor mortis

As rigor mortis ( med - lat. Rigor mortis, rigor mortis ' ) refers to the after death ( post mortem ) enters solidification of the muscles. It is one of the safe signs of death.

It is caused by the rigid binding of myosin to the actin fibers: After inserting the death ATP is no longer regenerated from ADP. Ion pumps therefore cease their activity. Within the muscle cells hold the ion pumps the calcium concentration in the cytoplasm low. After the death of diffuse calcium ions from the sarcoplasmic reticulum into the cytoplasm, which eventually leads to the binding of myosin to actin filaments, because the calcium ions remove the insulating effect of troponin. The binding is no longer canceled due to the absence of ATP, the frozen muscle (see contractile mechanism ).

In humans, the rigor mortis begins at room temperature after about 1 to 2 hours on the eyelids, muscles of mastication ( 2-4 hours) and small joints, after which it begins to neck and on the body down, and is fully developed after 6 to 12 hours ( slower in heat faster in cold weather ). This sequence, described by the Nysten rule, is found only in about 50 % of cases.

Decisive is that solidify the individual fibers of a muscle only gradually. If the stiffness of a muscle broken by foreign movements before it is fully formed ( ie within the first 14 to 18 hours) in this muscle, is after some time a new Rigid one, due to the fibers, which were not previously frozen. Heat and increased strain on the muscles accelerate shortly before the time of death, the onset of rigor mortis. By decomposition processes, the Rigid 24 begins no later than 48 hours post mortem, to solve at the beginning of autolysis and resumes afterwards not again.

With this option, the time allocation is the rigor mortis in the right medicine for a first confinement time of death of meaning. This method takes advantage inter alia, the facts described above exploits the fact that it mortem is only possible within a certain time period post to determine their re- insertion after the artificial breaking of rigor.