(Latin: stiff, hard, numb; to be frozen, to grow stiff with cold, to be chilled)
2. The hardening of the muscular tissues of the body, from one to seven hours after death as a result of the coagulation of the myosinogen and paramyosinogen: The cadaveric rigidity disappears after one to five or six days, or when decomposition begins.
Sometimes the rigor mortis, or cadaveric rigidity in the corpse, makes it difficult to fit the body into the coffin for burial.3. The postmortem stiffening of the voluntary and involuntary muscles of the body present a board-like situation for the entire body: The development of cadaveric rigidity may be poor or incomplete in elderly, very young, or severely debilitated individuals.
A patient with catatonic rigidity may remain in one position for minutes, days, or even longer.
This gives way abruptly if the pressure to produce flexion is continued.2. An initial marked resistance to passive movement, which then suddenly gives way.
This variety of increased muscle tone is characteristic of spasticity as a result of disease or dysfunction of the pyramidal tracts.
The term parkinsonism is any of a group of nervous disorders similar to Parkinson's disease, marked by muscular rigidity, tremor, and impaired motor control and often having a specific cause; such as, the use of certain drugs or frequent exposure to toxic chemicals.
It is also called Parkinson's syndrome or it may actually refer to having Parkinson's disease.
This can be produced by a variety of metabolic and structural brain disorders.
2. Etymology: from Old French rigor, from Latin rigorem, rigor, "numbness, stiffness", from "heat" + rigere, "to be stiff".
The detection of this phenomenon is important because the body maintains the postion it was in at the time of death and this positioning continues until true rigor mortis develops.
2. The generalized nervous disorder marked by symptoms of trembling limbs and muscular rigidity as seen in parkinsonism (a syndrome similar to Parkinson disease; for example, as a side effect of an antipsychotic drug).
Parkinson disease: a slowly progressive neurologic disease characterized by a fixed unexpressive face, a tremor (shaking) when at rest, slowing of voluntary movements, walking with short fast steps, a peculiar posture and muscle weakness, caused by degeneration of an area of the brain called the basal ganglia, and by low production of the neurotransmitter dopamine.
Most patients are over fifty, but at least ten percent are under forty. It is also known as paralysis agitans and shaking palsy.
2. The increased muscular tension and shortness that cannot be released voluntarily and prevents lengthening of the muscles involved.