Analyzing Changes in Nerve Excitability Parameters for Diagnostic Insights in Cervical Radiculopathy
DOI:
https://doi.org/10.53555/ejac.v20i1.1144Keywords:
Strength-Duration Curve, Rheobase, Chronaxie, Cervical Radiculopathy, Neurophysiology, Diagnostic PrecisionAbstract
Chronaxie and Rheobase are essential measures of nerve excitability and conduction. This study examines the influence of cervical radiculopathy on these parameters and their potential diagnostic value. Thirty patients with cervical radiculopathy and thirty healthy controls were evaluated for Strength-Duration Curve (SDC) parameters. Findings indicated significantly elevated Rheobase (7.0 mA vs. 5.04 mA) and prolonged Chronaxie (0.36 ms vs. 0.25 ms) in the patient group (p < 0.05). The study underscores the clinical utility of SDC in refining diagnostic precision and guiding targeted therapeutic interventions. Methods:This cross-sectional observational study included 30 patients with cervical radiculopathy and 30 healthy controls (ages 33-47, matched for age and gender). Rheobase and Chronaxie were measured using a microcontroller-based diagnostic muscle stimulator. Independent t-tests were conducted to compare SDC parameters between groups. Ethical approval was obtained from the IAMR Research and Ethics Committee. Results: Cervical radiculopathy patients exhibited significantly higher Rheobase (7.0 ± 0.35 mA) compared to controls (5.04 ± 0.24 mA) (p < 0.001). Chronaxie values were also prolonged in patients (0.36 ± 0.03 ms) versus controls (0.25 ± 0.02 ms) (p < 0.001). These findings suggest impaired nerve excitability and conduction, supporting SDC as a complementary diagnostic tool. Discussion: The study confirms that cervical radiculopathy significantly alters SDC parameters, reflecting underlying neurophysiological dysfunction. The prolonged Chronaxie and elevated Rheobase suggest axonal damage and demyelination, reinforcing SDC's potential in differential diagnosis. These findings align with previous research on lumbar radiculopathy and peripheral neuropathy. Conclusion : SDC testing provides valuable diagnostic insights into cervical radiculopathy. Elevated Rheobase and prolonged Chronaxie serve as objective markers of nerve dysfunction, enhancing diagnostic accuracy and treatment planning. Future studies should explore longitudinal assessments and therapeutic interventions targeting SDC parameter normalization.
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