2. The circumstances in which a substance renders something inflexible, stiff, or non-pliable.
3. In physiology, a functional conditon of the skeletal muscles, characterized by a marked increase in their tone and in their resistance to deformation.
Muscle rigidity results from changes in the character of the neural influences that the central and peripheral nervous systems continuously exert on the muscles.
4. The quality of being rigid and rigorously severe in discipline, rules, or behavior.5. Tenseness; immovability; stiffness; inability to bend or to be bent.
6. In psychiatry, an excessive resistance to change.
7. In medicine, stiffness or inflexibility; especially, that which is abnormal or morbid.
8. In neurology, one type of increase in muscle tone when it is at rest; it is characterized by increased resistance to a passive stretch, independent of velocity (speed), and is symmetric around the joints.
It increases with the activation of the corresponding muscles in the contralateral limb.
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. 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.
It is recognized widely as the most common sign, after early infancy, of meningeal irritation, notably of meningitis and bleeding into the subarachnoid space which is the layer of tissue situated or occurring between the arachnoid (like a cobweb of fibers) and the pia mater (the delicate and highly vascular, blood vessels, membrane immediately investing [covering or enveloping] the brain and the spinal cord).
When doctors move a person's limb passively around a joint, they note the degree of resistance to movement (muscle tone).
Muscle tone which is uneven and suddenly increased (spasticity) may be a result of a stroke or spinal cord injury.
Muscle tone that is evenly increased (rigidity) may be caused by disease of the basal ganglia; such as, Parkinson's disease.
Muscle tone is severely reduced (flaccid) immediately and temporarily after a spinal cord injury produces paralysis.
Glaucoma is a group of eye diseases characterised by an increase in intraocular pressure which causes pathological changes in the optic disk and typical defects in the field of vision.