Reflex Grading Scale
Reflexes are categorized on a 0 to 4+ scale, where 0 indicates absent reflex, 1+ is diminished/hypoactive, 2+ is normal, 3+ is brisker than average, and 4+ is hyperactive with clonus. 1
Standard Grading System
The deep tendon reflex grading system applies uniformly across all reflexes (including tricep, ankle, knee, and other myotatic reflexes) using the following scale: 1
- 0: Absent reflex - no response elicited 1
- 1+: Diminished or hypoactive - trace response that is less than normal 1
- 2+: Normal reflex - average expected response 1
- 3+: Brisker than average - possibly but not necessarily pathologic 1
- 4+: Hyperactive with clonus - definitively abnormal 1
Clinical Interpretation
Diminished or absent reflexes (0-1+) suggest lower motor neuron dysfunction, including peripheral neuropathy, nerve root compression, anterior horn cell disease, neuromuscular junction disorders, or myopathies. 1
Hyperactive reflexes (3-4+) indicate upper motor neuron dysfunction, including corticospinal tract lesions, spinal cord pathology, or cerebral lesions affecting motor pathways. 1
Critical Clinical Considerations
Asymmetry in reflexes between sides is often more clinically significant than the absolute grade. Comparison of reflexes bilaterally may indicate focal pathology, even when both sides fall within the "normal" 2+ range. 1
Each specific reflex tests particular nerve roots and pathways - for example, the tricep reflex specifically evaluates C7-C8 nerve roots and radial nerve integrity, making it valuable for localizing cervical radiculopathy or peripheral nerve lesions. 1
Documentation of factors affecting the examination (patient cooperation, anxiety, medications such as baclofen which inhibits reflexes at the spinal level) aids in accurate interpretation of the reflex response. 1, 2