Nysten’s rule pertains to ?
a) Rigor mortis
b) Identification
c) Bullet injuries
d) Putrefaction
Correct Answer - A
Ans. is ‘a’ i.e., Rigor mortis
Rigor mortis
It is defined as contraction, stiffening, shortenig and opacity of
muscles after death.
It occurs after molecular (cellular) death. In tropical countries (e.g.
india), it begins 1-2 hours after death, takes further 2 hours to
develop, and lasts for 18-36 hours in summer and 24-48 hours in
winter.
In temperate countries, it begins in 3-6 hours, takes further 2-3 hours
to develop and lasts for 2-3 days.
All muscles of body are involved, i.e. voluntary or involuntary.
However, it does not start in all muscles simultaneously (nysten’s
rule).
Involuntary muscles (heart) are involved first than voluntary muscles.
Sequence of muscles involvement is as follows : Heart > upper
eyelid > neck > jaw > face > chest > upper limb > abdomen > lower
limb > finger and toes.
It passes off in the same order in which it has appeared.