Revisiting the Urge to Operate: One-year Neurophysiological Follow-up in Severe CTS

Abstract

Background and Aim: Several approaches have been proposed for the treatment of Carpal Tunnel Syndrome (CTS) based on its severity. The aim of this study is to determine the optimal management for severe CTS. Methods and Materials/Patients: This cross-sectional study was conducted for 22 months from August 2017 to June 2019 in a referral rehabilitation clinic in southern Iran. A total of 117 hands diagnosed with severe CTS were included in 78 patients according to Electrodiagnostic Study (EDX) reports (considering Sensory Proximal Latency (SPL) >3.6 msec, Sensory Distal Latency (SDL) >5.3 msec, Sensory Nerve Conduction Velocity (SNCV) <30 m/sec, Distal Motor Latency (DML) >6.5 msec as being severe) who refused to undergo surgery. Boston questionnaire was filled out and conventional EDX was carried out at the first and the 1-year follow-up visits. Results: In patients with a detectable Sensory Nerve Action Potential (SNAP), motor amplitude (P<0.002) and latency (P<0.01), SPL (P<0.003) and SNCV (P<0.006), and Boston parameters improved significantly in the one-year follow-up visit compared with the results at the first visit. However, improvement in patients with absent or low amplitude SNAP at the first visit was only observed in proximal sensory latency (P<0.005) and amplitude (P<0.003). Conclusion: There is a considerable chance for non-surgical improvement of patients with severe CTS in terms of symptom relief, hand function, and EDX parameters in those with detectable SNAP at the first visit; however, patients with undetectable SNAP have little, if any, the chance for improvement with conservative measures.

Effects of repetitive peripheral magnetic stimulation vs. conventional therapy in the management of carpal tunnel syndrome: a pilot randomized controlled trial

“…SNAP or CMAP amplitude was not typically discussed, which may be because the primary diagnostic criteria for CTS centered on DML and DSL, and the improvement in these parameters can indicate a change in CTS severity. Ashraf et al (2020) reported that SNAP appeared in 63% of patients with severe CTS after an initial absence of SNAP following a 1-year follow-up electrodiagnostic study. Furthermore, in patients with low SNAP findings, SNAP amplitude and sensory latency at the wrist showed significant improvement ( Ashraf et al, 2020 ).…”

“… Ashraf et al (2020) reported that SNAP appeared in 63% of patients with severe CTS after an initial absence of SNAP following a 1-year follow-up electrodiagnostic study. Furthermore, in patients with low SNAP findings, SNAP amplitude and sensory latency at the wrist showed significant improvement ( Ashraf et al, 2020 ). Therefore, we suggest that the increase in SNAP amplitude in this study may be indicative of an early neurophysiological improvement; however, this requires further investigation.…”