Nysten's rule

Nysten's rule (1811) describes the sequential onset of rigor mortis in the various muscle groups. The basic sequence of the solidifying body begins from the head down the body, in the order:
 * Involuntary muscle first: Heart
 * Upper eyelids
 * Neck
 * Jaw
 * Face
 * Upper extremities
 * Muscles of the trunk
 * Lower extremities

The rule does not occur in all cases, as described. In particular, it depends on what muscle groups are even claimed before the death - there enters rigor mortis then first one. It owes its name to the French pediatrician Pierre-Hubert Nysten (1771–1818).