Cadaver evaluation of EMG needle insertion techniques used to target muscles of the thorax

Study Design. Measure the accuracy of needle insertion in thoracic muscles of human cadavers. Objectives. Evaluate the effectiveness of known EMG techniques for sampling thoracic innervated muscles. Summary of Background Data. The evaluation of thoracic radiculopathies requires accurate electrodiagnostic techniques for evaluating the thoracic myotomes. Methods. An American Board of Electrodiagnostic Medicine certified physician placed needles into pertinent muscles of the thorax and an anatomist serving as a blinded dissector recorded the path and accuracy of needle. Results. Needle examination of thoracic muscles was as accurate as limb needle examination. No notable risks are noted in multifidus sampling. However, in the cadaver, some risks were noted in association with placements in the intercostal muscles. The target muscle was reliably sampled, but the rib or vertebral level was difficult to landmark in the cadaver. Conclusions. Needle examination of the thoracic multifidus and intercostals is reliable, although further confirmation is needed to accurately verify the appropriate vertebral or rib level being sampled.