Triceps reflex

The triceps reflex is tested as part of the neurological examination to asses the sensory and motor pathways within the C7 and C8 spinal nerves. The triceps reflex originates from the triceps brachii muscle, and is initiated by the C7 nerve root.^[1]

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Testing

The test is performed by tapping the tendon while the forearm is hanging loose at a right angle to the arm. A sudden contraction of the triceps muscle causes extension of the forearm, and indicates a normal reflex.^[2][3]

Test indicators

• Normal: There are no problems detected.
• Absence of a reflex (areflexia): If no reflex is elicited then it is essential to try again with reinforcement, with the patient clenching his or her teeth just as the reflex hammer strikes.
• Hyper-reflexia (a response far larger than considered normal): Indicates a potential upper motor neurone lesion.

Absence of reflex

An absence of reflex can be an indicator of several medical conditions: Myopathy, neuropathy, spondylosis, sensory nerve disease, euritis, potential lower motor neurone lesion, or poliomyelitis.^[4]

Other medical problems that may cause irregular reflexes include Hyperthyroidism and Hypothyroidism.

References