A patient has hyperactive reflexes of the lower extremities. How should the gerontological nurse practitioner assess for ankle clonus?

To assess for ankle clonus, sharply dorsiflexing the foot while supporting the knee is the appropriate technique. This method effectively tests for the presence of clonus by placing the patient’s ankle in a position that may elicit repetitive contractions if clonus is present. When the foot is dorsiflexed suddenly and held in position, the nurse can observe any rhythmic muscle contractions that might occur, indicating hyperactivity of the reflexes, characteristic of conditions such as upper motor neuron lesions.

The dorsiflexion moves the ankle into an excited state and can reveal the underlying neurological status. If clonus is present, the foot will display involuntary, rhythmic shaking.

While other options involve assessments related to reflexes or neurological function, they do not specifically target the mechanism for assessing ankle clonus. Options involving the tuning fork or percussion hammer serve different functions and would not adequately reveal the hyperactive reflexes indicated by clonus.