[Detection of axillary nerve multisegment motor nerve conduction using magnetic stimulation]

Area of Science:

• Neuroscience
• Clinical Electrophysiology
• Medical Imaging and Diagnostics

Background:

• Accurate assessment of axillary nerve function is crucial for diagnosing upper limb neurological disorders.
• Existing electrodiagnostic methods may have limitations in evaluating the proximal segments of the axillary nerve.
• Magnetic stimulation offers a non-invasive approach to nerve conduction studies.

Purpose of the Study:

• To establish a reproducible method for multi-segmental motor nerve conduction detection of the axillary nerve using magnetic stimulation.
• To investigate the clinical utility of this magnetic stimulation technique for evaluating axillary nerve function.
• To analyze the influence of age and anthropometric factors on axillary nerve conduction parameters.

Main Methods:

• Eighty healthy volunteers (40 male, 40 female) aged 18-74 were divided into five age groups.
• Magnetic stimulation was applied at three distinct points: subscapular fossa, infraclavicular fossa, and Erb's point.
• Axillary nerve motor responses were recorded from the deltoid muscle, measuring latency, amplitude, and detection distance.

Main Results:

• A high detection rate (97.2%) of axillary nerve waveforms was achieved.
• No significant differences in latency or amplitude were found based on side or gender (P>0.05).
• Latency showed significant differences with varying detection distances (P<0.05), and age significantly affected latency and amplitude (P<0.05), with older groups exhibiting prolonged latency and decreased amplitude.

Conclusions:

• The developed multi-segmental magnetic stimulation method for the axillary nerve is stable and reliable.
• This technique enables the evaluation of proximal nerve segments in the upper limbs.
• Age-related biological effects on nerve conduction must be considered when interpreting results.