H-reflex
An electrically evoked reflex response used in nerve conduction studies to assess the integrity of the afferent and efferent pathways of a monosynaptic reflex arc.
Full Definition
The H-reflex (Hoffmann reflex) is an electrically elicited analog of the monosynaptic stretch reflex. It is obtained by stimulating sensory fibers in a mixed nerve, which travel to the spinal cord and synapse with motor neurons that return to innervate the same muscle. The H-reflex is commonly recorded from the soleus muscle by stimulating the tibial nerve. It provides valuable information about the functional integrity of the S1 nerve root, peripheral nerve, and central nervous system pathways. The H-reflex is particularly useful in diagnosing S1 radiculopathy and polyneuropathy.
Usage
Usage note: Always hyphenate. Capital H followed by hyphen and lowercase reflex.
In Context
- "The H-reflex was absent bilaterally, suggesting S1 radiculopathy." — Nerve conduction study report
- "H-reflex latency was prolonged compared to normative values." — Electrodiagnostic interpretation