Submitted by Lisa M. Williams, MD, News Science Editorial Board
Edited by Niranjan N. Singh, MD, News Science Editorial Board
Lee SJ, Kim KH, Cheong IY, Park BK, Kim DH. Safety Window for the Volar Needle Approach for Examination of the Pronator Quadratus Using Ultrasonography. Arch Phys Med Rehabil
2017 May 26. pii: S0003-9993(17)30328-3. doi: 10.1016/j.apmr.2017.04.019. [Epub ahead of print]
The pronator quadratus (PQ) is the most distal muscle innervated by the median nerve and important in the work-up when differentiating proximal versus distal median mononeuropathy and plays an important role in diagnosing anterior interosseous nerve (AIN) syndrome. Various approaches have been suggested for evaluation of the muscle by electromyography. In this study, the authors aim to investigate PQ anatomy and determine the proper volar needle insertion using ultrasonography in 25 volunteers and 50 PQ samples.
Use of the volar approach for needle electromyographic examination of the PQ may be safer than previously described medial or dorsal approaches. Though dorsal approach is still most popular – the “gold standard” and practiced by most electromyographers – the volar approach can be used in select patients.