PM&R ROUNDS   •   August 28, 2017

We believe that every PM&R doc should take a look at this article titled How Electrodiagnosis Predicts Clinical Outcome of Focal Peripheral Nerve Lesions, because it further elucidates the importance of EDX consultants in providing a prognosis for nerve lesions. For those who are in practice, CME credit is available through the AANEM.

Why We Love This Article

Reviews the classification tools used to determine severity of nerve injury. The authors do an excellent job in reviewing the Seddon and Sunderland classifications of nerve injury. They further relate the classifications to prognosis; from neuropraxia to neurotmeis. Other factors reviewed that may determine prognosis includes the degree of demyelination, axon loss and muscle distance.

Discussed EDX measures that can estimate prognosis. In EDX, we primarily look at CMAP, SNAP, conduction velocities, spontaneous activity and motor unit morphology. You will review the relationships between these EDX measures and prognosis. The article goes into great depths to explain how CMAP/SNAP latencies and amplitudes can be correlated to prognosis. EMG findings at rest and during recruitment were also well correlated with prognosis.

EDX challenges are reviewed. We all know that there are many pitfalls to EMG testing. Knowing these pitfalls is especially important when attempting to give a prognosis for nerve recovery to a patient or referring physician. How nerve injury variability including location, pathophysiology and severity are reviewed. In addition, the importance of proper timing for EDX studies is stressed.

The variability between common nerves is explained. As we know, some nerves are more easily injured, while other nerves heal better than others for various reasons. This article reviews the anatomical and recovery variables between the median, ulnar, radial, fibular and facial nerves; as well as, the brachial plexus (preganglionis vs. postganglionic lesions). Specific findings noted during EDX testing are explained, that can be used to estimate prognosis.

Add This Article to Your Vault

As physiatrists, we strive to be among the best electromyographers in medicine. This article will surely help you to increase your knowledge base regarding prognosis of nerve injuries. Not only is it helpful to diagnose neuromuscular disorders, but it is also helpful to guide your patients and referring physicians in management options based on prognosis.

We hope you enjoy this read.