Changes in H‑reflex and V‑waves following spinal manipulation
Imran Khan Niazi · Kemal S. Türker · Stanley Flavel · Mat Kinget · Jens Duehr · Heidi Haavik
Introduction: Over the past 10 years, several research groups have
demonstrated that spinal manipulation can change various aspects of nervous system function, including muscle reflexes, cognitive processing, reaction time, and the speed at which the brain processes information (Murphy et al. 1995; Herzog et al. 1999; Suter et al. 1999, 2000; Kelly et al. 2000; Haavik Taylor and Murphy 2007a, b, 2008, 2010a).
Methods: SA total of 18 men took part in the study. Study one included ten volunteers aged 27.6 ± 5.4 years, and study two included six volunteers aged 32.6 ± 9.3 years. All subjects were required to be aged 18–40, have evidence of spinal dysfunction but have no known contraindications to spinal manipulation such as recent history of trauma, known conditions such as metabolic disorders, inflammatory or infectious arthropathies, or bone malignancies.
Results: In ten subjects using the two procedures, we obtained 20 sets of results. To be able to fully characterize the possible changes in the motoneuron excitability and the synaptic efficacy, the M-wave and H-reflex curves were established. For that, 16 levels of stimuli were utilized.
Conclusions: This study discovered three original findings: Firstly, that,
the H-reflex pathways can be significantly affected by the spinal manipulation; and, secondly, that, the cortical drive as expressed by the size of the V-wave and the SEMG and force measure during MVC is significantly increased by the spinal manipulation. Thirdly, the spinal manipulation intervention appears to have prevented fatigue from occurring in the SOL, as indicated by a significant decrease in median frequency in the power spectrum from the control subjects’ SEMGs only.