Tricep Reflex Grading
The tricep reflex is graded on a standard 0-4+ scale, where 0 indicates absent reflex, 1+ is diminished, 2+ is normal, 3+ is brisker than average, and 4+ is hyperactive with clonus.
Standard Grading Scale
The deep tendon reflex grading system applies uniformly to the tricep reflex 1:
- 0: Absent reflex - no visible or palpable muscle contraction
- 1+: Diminished or hypoactive - trace response, less than normal
- 2+: Normal - average, expected response
- 3+: Brisker than average - possibly but not necessarily pathologic
- 4+: Hyperactive with clonus - sustained rhythmic contractions, definitively abnormal
Testing Technique
To properly elicit the tricep reflex 1:
- Position the patient's arm flexed at approximately 90 degrees at the elbow
- Support the arm either by holding it or having it rest comfortably
- Strike the triceps tendon directly above the olecranon process with a reflex hammer
- Observe for elbow extension as the triceps contracts
- Test both sides for comparison and symmetry
Clinical Significance of Abnormal Responses
Diminished or Absent Reflexes (0-1+)
Hyporeflexia or areflexia indicates lower motor neuron dysfunction 1:
- Peripheral neuropathy
- Nerve root compression (particularly C7-C8 radiculopathy for triceps)
- Anterior horn cell disease
- Neuromuscular junction disorders
- Myopathies (including muscular dystrophies with elevated creatine kinase) 1
Hyperactive Reflexes (3-4+)
Hyperreflexia indicates upper motor neuron dysfunction 1:
- Corticospinal tract lesions
- Spinal cord pathology above the reflex level
- Cerebral lesions affecting motor pathways
- When accompanied by clonus (4+), this is definitively pathologic and indicates significant upper motor neuron disease 1
Key Clinical Considerations
Asymmetry is often more significant than the absolute grade - compare reflexes bilaterally, as side-to-side differences may indicate focal pathology even when both sides fall within the "normal" range 1.
The tricep reflex specifically tests the C7-C8 nerve roots and radial nerve integrity, making it valuable for localizing cervical radiculopathy or peripheral nerve lesions 1.
In pediatric populations, persistence of abnormally brisk reflexes beyond expected developmental milestones may indicate cerebral palsy or other perinatal brain damage, particularly when accompanied by abnormal muscle tone and co-contraction patterns 2.
Document the patient's level of cooperation and any factors affecting the examination (such as anxiety, which can transiently increase reflexes, or medications like muscle relaxants, which can diminish them) to aid in interpretation 1.