Assessing Reflexes
Overview
How to Elicit
- Biceps - ask the patient to relax their arms in their lap and strike the biceps tendon with a tendon hammer.
- Supinator - ask the patient to relax their arms in their lap and strike the brachioradialis tendon, proximal to the wrist on the lateral aspect of the forearm.
- Triceps - lift the patient’s shoulder into abduction and internal rotation, with the arm flexed to 90°. Strike the triceps tendon with a tendon hammer.
- Patellar - with the patient supine, support the knee from underneath providing slight flexion and strike the patellar tendon below the patella.
- Achilles - flex the knee, externally rotate the hip and dorsiflex the foot. Strike the Achilles tendon of the heel.
- If the reflex is difficult to elicit, reassess the reflex while the patient clenches their teeth.
Interpretation
- No response (hyporeflexive)Lower motor neuron lesion
- Diminished (low normal)Lower motor neuron lesion
- Average (normal)
- Brisk (high normal)Upper motor neuron lesion
- Very brisk (hyperreflexive)Upper motor neuron lesion
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