As many of our chiropractic customers know, tuning forks can be useful tools in detecting radiculopathy. This is especially apparent in unilateral cases. It is even noted, sometimes incidentally, in the podiatry clinic. The ETF is adept at detecting these disparities due to the quantitative results inherent in its timed vibration test (TVT). An example of this may be seen in patients with a 7-8 second differential between right and left limbs on the TVT. Further questioning of these patients often reveals an established history of a herniated disc or vague but recurrent complaints of low back pain or sciatica.
Now recent research out of Austria’s Medical University Innsbruck has confirmed the value of vibration testing in documenting sensation improvement after neurosurgery. In their 2017 article, The value of quantitative sensory testing in spine research, Tschugg et al. document pre- and postoperative values in a battery of quantitative sensory tests (QST) and self-assessment questionnaires in patients with MRI-confirmed single lumbar disc herniation undergoing sequestrectomy. Their findings confirmed significant postoperative improvement in vibration perception as detected by the Rydell-Seifer 64 Hz tuning fork. This quantitative vibration test along with “mechanical detection thresholds” (MDT) administered with customized von Frey hairs were noted to be the most important modalities for detecting and following sensory deficits in this patient population.
These findings may expand the role of quantitative vibration testing to include routine pre- and postoperative assessment of neurosurgery patients. Products like the Rydell-Seifer tuning fork and the ETFMx are ideally suited to this task due to their quantitative output and 64 Hz vibration frequency. Given the results of Tschugg and colleagues, these point-of-care tests along with the patient self-assessments described in their study could become the new standard for evaluating patient outcomes after neurosurgery.