Also known as the Jendrassik manoeuvre, reinforcement technique is a further method of testing for normal reflex response where it has been found to be absent by conventional reflex testing.
Where a reflex appears to be absent in the lower limb ask the patient to interlace the fingers and pull apart, thereby recruiting upper limb muscular contraction, whilst simultaneously re-testing for the reflex. For an upper limb reflex, ask the patient to grit the teeth whilst re-testing.
Where a reflex is absent but found to be present with reinforcement, this should be considered a normal reponse, but the need for reinforcement should be recorded in the notes. Where a reflex is still found to be absent despite reinforcement, a true absent reflex should be recorded
Factors affecting reflex responses include the correct use of the hammer and location of contact. Patient tension and focus may interfere with the reflex response: consider using distracting conversation during tests.