Examination Technique:

  • ensure the patient is relaxed.
  • for assessment in the upper extremities, the patient may be lying or sitting. In the lower extremities, tone is best assessed with the patient lying down.
  • explain the examination technique to the patient before proceeding.
  • spasticity (clasp knife) is velocity dependent and should be assessed by a quick flexion/extension of the knee or the elbow or quick supination/pronation of the arm.
  • rigidity (lead pipe) is continuous and not velocity dependent and the movement should be performed slowly.
  • “activated” rigidity; minor degrees of rigidity may be enhanced by having the patient activate the opposite limb.
  • rigidity in the neck can be assessed by slow flexion, extension and rotation movements

Normal Response:

normally minimal, if any resistance to passive movement is encountered.

Abnormal Response:

  • spasticity is a feature of an upper motor neuron lesion and maybe minor such as a spastic catch or a very stiff limb that cannot be moved passively. Accompanying features may include spasms, clonus, increased deep tendon reflexes and an extensor plantar response.
  • rigidity is a continuous resistance to passive movement and is seen in extrapyramidal disorders such as Parkinson’s disease.
  • rigidity may be continuous or ratchety (cogwheeling). Cogwheeling is typically seen at the wrists.
  • hypotonia (flaccidity) or decreased tone is more difficult to appreciate but is seen with lower motor neuron or cerebellar lesions