Eliciting Clonus (Testing)
Clonus at the ankle is tested by rapidly flexing the foot into dorsiflexion (upward), inducing a stretch to the gastrocnemius muscle. Subsequent beating of the foot will result, however only a sustained clonus (5 beats or more) is considered abnormal. Clonus can also be tested in the knees by rapidly pushing the patella (knee cap), towards the toes.
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