Accuracy of Palpation‐Guided Versus First Attempt at Ultrasound‐Guided Electromyography Needle Placement for the Extensor Carpi Radialis Longus and Brevis by Trainees
James B. Meiling, Kitty Y. Wu, Andrea J. Boon, Marianne T. LuetmerABSTRACT
Introduction/Aims
Ultrasound (US) guidance may be essential for accurate electromyography (EMG) needle placement in less‐commonly evaluated muscles, such as the extensor carpi radialis longus (ECRL) and brevis (ECRB), and particularly for identifying suitable donor muscles prior to tendon transfers to restore upper extremity function. Our primary aim was to compare the accuracy of trainee palpation‐guided versus first‐attempt US‐guided needle placement. Our secondary aim was to describe the locations of inaccurate needle placement.
Methods
Seven subjects each performed four needle placements (ECRL and ECRB, both palpation‐guided and US‐guided), totaling 28 placements into a cadaveric specimen. US‐guided needle placement was performed with one attempt after one live demonstration.
Results
No palpation‐guided ECRL attempts were accurate while only two of the palpation‐guided ECRB attempts were accurate. First‐attempt US‐guided needle placement was significantly more accurate overall (64.3% vs. 14.2%, p = 0.020), and specifically for ECRL (71.4% vs. 0%, p = 0.025). Combining palpation‐guided ECRL and ECRB attempts, the needle was inadvertently placed in the extensor digitorum communis (50%), extensor carpi ulnaris (16.7%), and brachioradialis (16.7%). Both US‐guided ECRL‐intended errors involved placing the needle into the adjacent ECRB.
Discussion
This study suggests that EMG needle placement into ECRL and ECRB by trainees may be more accurate with US guidance. Accurate preoperative individual needle assessments of both wrist extensors are essential for patients with tetraplegia considering reconstructive surgery to restore functional grasp and should be performed with US guidance.