Difference between Rigor Mortis and Cadaveric Spasm

Though rigor mortis and cadaveric spasm both occur both following death but they are totally different things. Cadaveric spasm is a localized contraction of muscle that was occurring during the time of death and perisisted then after unlike Rigor mortis which developed through out the body including visceral muscle. There is a period of flaccidity before rigor mortis  develops. The following points helps us differentiate between the cadaveric spam and rigor mortis.

Know the physiology behind rigor mortis 

Character	Rigor Mortis	Cadaveric Spasm
Time Of Onset	Within 1-2 hours of death	At the time of Death
Occurrence	Occurs in all death except burn	Predisposed by sudden violent death
Muscle	Both Voluntary and involuntary Muscle Heart is the first to be involved Small muscle of digits develop it last	Local Voluntary Muscle eg. Hand with knife in suicide
Muscle Stiffening	Moderate force required to break it	Great Force required to break
Primary flaccidity	Occurs	Does not occur
Mechanism of Production	Known	Still Obscure
Response of Electrical Stimuli	Absent	Present
Medico Legal Importance	Gives idea about Time since death	Gives idea about Mode of Death