Asian Spine J.  2017 Feb;11(1):99-104. 10.4184/asj.2017.11.1.99.

A Comparison of Interside Asymmetries of Lower Extremity Somatosensory Evoked Potentials in Anesthetized Patients with Unilateral Lumbosacral Radiculopathy

• Yue Q
• Hale T
• Knecht A

• KMID: 2391593
• DOI: http://doi.org/10.4184/asj.2017.11.1.99

Abstract

STUDY DESIGN: Prospective cohort study. PURPOSE: This study was to investigate interside asymmetries of three lower extremity somatosensory evoked potentials (SSEPs) in anesthetized patients with unilateral lumbosacral radiculopathy. OVERVIEW OF LITERATURE: Although interside asymmetry is an established criterion of abnormal SSEP, little is known which of the lower SSEPs is more sensitive in detecting interside asymmetry in anesthetized patients.
METHODS
Superficial peroneal nerve SSEP (SPN-SSEP), posterior tibial nerve SSEP (PTN-SSEP), and sural nerve SSEP were obtained in 31 lumbosacral surgery patients with unilateral lumbosacral radiculopathy, and compared with a group of 22 control subjects.
RESULTS
The lumbosacral group showed significant larger interside asymmetry ratios of P37 latencies in SPN-SSEP and PTN-SSEP, and significant larger interside asymmetry ratio of P37-N45 amplitude in SPN-SSEP, when comparing with the control group. Within the lumbosacral group but not the control group, SPN-SSEP displayed significant larger interside asymmetry ratio in P37 latency. When referencing to the control group, more patients in the lumbosacral group displayed abnormal interside SPN-SSEP latency asymmetries which corroborated the symptom laterality.
CONCLUSIONS
The data suggested that SPN-SSEP was more sensitive in detecting interside latency asymmetry in anesthetized patients.

Keyword

Superficial peroneal nerve; Posterior tibial nerve; Sural nerve; Somatosensory evoked potential; Radiculopathy

MeSH Terms

Cohort Studies
Evoked Potentials, Somatosensory*
Humans
Lower Extremity*
Peroneal Nerve
Prospective Studies
Radiculopathy*
Sural Nerve
Tibial Nerve