What does clasp-knife rigidity indicate?
A form of muscular spasm or exaggerated muscle tonus in a limb or body part that resists passive movement and then suddenly gives way, in the manner of a jackknife. It is indicative of a lesion in the corticospinal tract.
What causes clasp-knife spasticity?
Mechanism. This reflex is observed in patients with upper motor neuron lesions. It was frequently attributed to the action of the golgi tendon organ, likely because of early studies showing that tendon organs are activated by strong muscle stretch and inhibit motoroneurons of the stretched muscle.
Is clasp-knife spasticity or rigidity?
Clasp knife rigidity describes the phenomenon in a spastic limb where, after an initial resistance to passive movement of a joint, there is a sudden reduction in tone and the limb moves quite freely through the rest of the range of the particular movement.
What is clasp-knife deformity?
Enlarged downward projecting spinous process of L5 vertebra extending up to sacral vertebrae with associated bifida defects is known as “Clasp-knife deformity”. It is often the cause of backache particularly during bending movements and called “Clasp-knife syndrome”.
What diseases do you see clasp-knife upper motor neuron rigidity and spasticity?
With upper motor neuron lesions the muscles, after an initial period of rigidity and resistance to movement, suddenly relax or give way, the so-called “clasp-knife” rigidity. Additionally, patients with Parkinson’s disease may show a cogwheel type of rigidity.
Is there any neurological condition in which extended limb show clasp-knife reaction?
Clinically spasticity manifests as an increased resistance offered by muscles to passive stretching (lengthening) and is often associated with other commonly observed phenomenon like clasp-knife phenomenon, increased tendon reflexes, clonus, and flexor and extensor spasms.
What diseases do you see clasp knife upper motor neuron rigidity and spasticity?
Is there any neurological condition in which extended limb show clasp knife reaction?
Where is clasp-knife rigidity?
clasp-knife rigidity increased tension in the extensor of a joint when it is passively flexed, giving way suddenly on exertion of further pressure; seen especially in upper motor neuron disease.
What is the other name of clasp-knife reflex?
Brain’s reflex extension of a hemiplegic flexed upper limb when a person is in a quadrupedal posture; called also quadrupedal extensor reflex.
Why does spasticity happen?
Spasticity is generally caused by damage or disruption to the area of the brain and spinal cord that are responsible for controlling muscle and stretch reflexes. These disruptions can be due to an imbalance in the inhibitory and excitatory signals sent to the muscles, causing them to lock in place.
Does Parkinson’s have clasp-knife rigidity?