Science News: Anatomical Study and Proposed EMG Technique for the Cervical Paraspinal Muscles
Published June 24, 2024
Science News
Submitted by: Oksana Sayko, MD
Edited by: Rebecca O'Bryan, MD
Citation: Haig AJ, McGuire TJ. Anatomical study and proposed EMG technique for the cervical paraspinal muscles. PM R. 2024;16(2):165-173. doi:10.1002/pmrj.13046
A library search found 32 anatomy texts published between 2000 and 2021. Of these, 11 were unique and appropriate. Most texts described the basic muscle anatomy similarly, but only one cited original research.
Most anatomy texts agree on some generalities but fail to agree on finer details such as the number of levels the multifidus spans (two to five, two to four, three) or the precise attachment points in the different sections of the spine (transverse process or articular process). These are crowded into a small area between the spinous processes and transverse processes.
Based on the understanding of reviewed textbook resources, the authors proposed a cervical paraspinal mapping technique that involves skin insertions from 1 to 2 cm lateral to the C5, C7, and T2 spinous processes. The needle samples transversely and deep toward midline, contacts bone, then is withdrawn and redirected to sample medial and caudally to midline to bone, creating two scores of 0–4 at three levels, theoretically resulting in scores of 0–24.
The author admits that the targeted muscle is small and deep. It is deep under other muscles and a specific fascicle of the muscle, potentially innervated by only one posterior primary ramus, may be only a few millimeters thick. EMG of the cervical paraspinals that does not target this small space between the spinous process and the transverse process is likely to miss all of the muscle, and even within that space one cannot be confident that the intended root-specific fascicle has been sampled. This is in contrast to the relatively large lumbar multifidus, which is mostly not overlapped by other muscles.
This technique must be validated by clinical research to determine the range of normal, reproducibility, and the spectrum of findings in various disorders.
Comments: This article proposes a method of potentially more reliable diagnosis and localization of cervical radiculopathy based on paraspinal muscles sampling. Cervical radiculopathy is a common pathology seen in the EMG lab. More precise localization may add to more specific treatment.