Journal CME, July 2023: Passive wrist deviation to increase the ultrasound identified procedural safe zone in carpal tunnel syndrome: A retrospective cohort study-Passive Wrist Deviation

Passive Wrist Deviation

Pdf Summary

The study, conducted by James B. Meiling DO, John H. Hollman PhD, Alexander Y. Shin MD, and Jeffrey S. Brault DO from the Mayo Clinic, investigates the optimal wrist positioning to maximize the safe zone distance between the median nerve and the ulnar artery during ultrasound-guided procedures in patients with Carpal Tunnel Syndrome (CTS). CTS is a common peripheral nerve entrapment syndrome that can lead to significant discomfort and functional impairment. Prior studies have noted the anatomical variations of the median nerve and carpal arch with different wrist positions, but the specific effect on the safe zone distance during radial and ulnar wrist deviations had not been previously examined.<br /><br />The retrospective cohort study included 25 patients (41 wrists) who had CTS confirmed with electrodiagnostic studies (EDX) within a year before enrollment. The researchers used ultrasound to measure the distance between the median nerve and ulnar artery in three wrist positions: neutral, ulnar deviation, and radial deviation.<br /><br />Results indicated that the safe zone distance was significantly greater in ulnar deviation (1.08 cm) compared to both the neutral (0.61 cm) and radial deviations (0.52 cm). There was no significant difference in safe zone measurements based on the severity of CTS classification or the dominance of the limb.<br /><br />The study concludes that ulnar deviation of the wrist increases the safe zone distance, thereby potentially enhancing the safety of ultrasound-guided injections by minimizing the risk of complications such as intra-arterial or intraneural injections. This finding has practical implications for improving the procedural safety of ultrasound-guided treatments for CTS.<br /><br />The study acknowledges limitations, including its retrospective design and variability in the timing of EMG tests relative to the ultrasound measurements, which could affect the progression of CTS.<br /><br />The study was published in PM&R, and the complete text, including CME information, is available online.

Keywords

Carpal Tunnel Syndrome

CTS

ultrasound-guided procedures

median nerve

ulnar artery

wrist positioning

safe zone distance

ulnar deviation

retrospective cohort study

Mayo Clinic