Ultrasound-Guided Near-Nerve Needle Recording in Sensory Conduction Study of the Superficial Fibular Nerve
Haruki Nakano1, Aishi Okazaki2, Ryuichi Saura1
1Department of Physical and Rehabilitation Medicine, Division of Comprehensive Medicine, Osaka Medical and Pharmaceutical University, Takatsuki, Japan.
Introduction/Aims:
The sensory nerve action potential (SNAP) of the superficial fibular nerve (SFN) is occasionally small and difficult to obtain using conventional surface recording (SR) or near-nerve needle recording. This study aimed to demonstrate a novel method of sensory conduction study of the SFN using ultrasound-guided near-nerve needle recording (US-NNNR) to obtain larger amplitude recordings.
Methods:
Twenty healthy volunteers (40 legs) were analyzed. In the conventional sensory conduction study using SR, we stimulated the nerve on the lateral aspect of the mid lower leg. The SNAPs of the medial dorsal cutaneous nerve (MDCN) and intermediate dorsal cutaneous nerve (IDCN) of the SFN were recorded at the ankle. In the US-NNNR, the SFN was scanned on the lateral aspect of the mid lower leg and a needle electrode was inserted with an out-of-plane approach < 1 mm from the SFN. Through the needle electrode, we recorded the SNAPs evoked by the stimulation of the MDCN or IDCN at the ankle. The SNAP amplitudes were compared between the SR and US-NNNR using the Wilcoxon signed-rank test.
Results:
The SNAP amplitude was significantly larger with US-NNNR than with SR for both the MDCN (p < 0.001) and the IDCN (p < 0.001).
Discussion:
US-NNNR in sensory conduction study of the SFN produced a larger SNAP amplitude than SR. The larger SNAP observed using US-NNNR may aid in the diagnosis of disorders involving the SFN.
