37^th European Neurology Congress

Biography

Biography: Isha Akulwar-Tajane

Abstract

Strength Duration Curve (SDC) is a plot of the threshold current versus pulse duration required to stimulate excitable tissue such as a nerve or muscle. This geometrical relationship makes it a quantitative and qualitative tool to assess electrophysiologic excitability. It is a routinely performed procedure for clinical identification of many neuromuscular conditions.

Radiculopathy is a clinical condition defined as pain and/or neurologic deficit in a specific nerve root distribution, including motor loss, sensory changes and sometimes depression of reflexes. It is caused by mechanical compression of a nerve root usually at the exit foramen or lateral recess. The intervertebral disc is the most important factor in Low Back Pain (LBP) and testing these subjects for nerve root lesions might be rewarding. In LBP patients, it is important to establish whether or not radiculopathy is present. This can be difficult when clinical, radiological & electromyographic abnormalities are not consistent with focal nerve root involvement. For many years, traditional electro diagnosis has been the main means of testing for radiculopathies caused by lumbar disc herniation. Determination of chronaxie values has been suggested as a method of studying intervertebral disc lesions. The assumption or basis is that the electrical excitability would be altered in muscles supplied by a nerve with a compressed root as a result of a disc herniation. This scoping review focuses on the role of SDC in radiculopathy and discusses its importance; procedural approach; parameters of significance; limitations; and implications for clinical practice and research. Literature search for the present study identified four clinical experimental studies using chronaxie alone and/or with SDC in patients with suspected disc pathology published between the years 1952 to 2015. Results of the study suggest that SDC and chronaxiemetry can serve as an electrical equivalent to myotomes testing & can help in localizing the level of disc lesion after causes of nerve affection have been ruled out by clinical evaluation. Chronaxie tests are practical and objective tests that can be very helpful to the clinician in correlation with other clinical and laboratory data. SDC plotting along with chronaxiemetry improves the accuracy and reliability. Together they offer a reliable, reproducible method for the detection of nerve root lesions resulting from disc pathology and assist in localization of the disorder to within two disc spaces and also can help in determining whether the disc bulge is unilateral or bilateral. This approach can complement assessment in the diagnostic phase prior to rehabilitation & in the monitoring of treatment effectiveness. In terms of clinical applications, the results of this study reinforce the need for quantitative evaluation & to reinstate electro-diagnostic procedures in clinical practice.