Flexor reflexes elicited by magnetic and electric stimulation of the sural nerve

OBJECTIVES: We have investigated whether magnetic stimulation of the sural nerve can evoke a flexor reflex recorded from the ipsilateral short head of the biceps femoris muscle. METHODS: The sural nerve was subjected to magnetic stimulation as well as by single-pulse electrical stimulation in healthy subjects. RESULTS: In 87% of the participants, a reflex response was elicited from the short head of biceps femoris muscle by magnetic stimulation of the sural nerve. In terms of latency and amplitude, this reflex response was similar to the flexor reflex response evoked from the same muscle by single-pulse electrical stimulation of the sural nerve. DISCUSSION: Findings indicate that flexor reflexes can easily be evoked from the short head of the biceps femoris muscle by magnetic stimulation of the sural nerve. The late component of the flexor reflex may not only be elicited via nociceptive afferents but may also involve non-nociceptive afferents.