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

  • 0
    No response (hyporeflexive)Lower motor neuron lesion
  • 1+
    Diminished (low normal)Lower motor neuron lesion
  • 2+
    Average (normal)
  • 3+
    Brisk (high normal)Upper motor neuron lesion
  • 4+
    Very brisk (hyperreflexive)Upper motor neuron lesion