Alterations in cortical and cerebellar motor processing in subclinical neck pain patients following spinal manipulation

Julian Daligadu, MHSc, Heidi Haavik, PhD, Paul Yielder, PhD, Julianne Baarbe, BSC (Hons), and Bernadette Murphy, DC, PhD

Objective: The purpose of this study was investigate whether there are alterations in cerebellar output in a subclinical neck pain (SCNP) group and whether spinal manipulation before motor sequence learning might restore the baseline functional relationship between the cerebellum and motor cortex.

Methods: Ten volunteers were tested with SCNP using transcranial magnetic stimulation before and after a combined intervention of spinal manipulation and motor sequence learning. In a separate experiment, we tested 10 healthy controls using the same measures before and after motor sequence learning. Our transcranial magnetic stimulation measurements included short-interval intracortical inhibition, long-interval intracortical inhibition, and cerebellar inhibition (CBI).

Results: The SCNP group showed a significant improvement in task performance as indicated by a 19% decrease in mean reaction time (P b .0001), which occurred concurrently with a decrease in CBI following the combined spinal manipulation and motor sequence learning intervention (F1,6 = 7.92, P b .05). The control group also showed an improvement in task performance as indicated by a 25% increase in reaction time (P b .001) with no changes to CBI.

Conclusions: Subclinical neck pain patients have altered CBI when compared with healthy controls, and spinal manipulation before a motor sequence learning task changes the CBI pattern to one similar to healthy controls. (J Manipulative Physiol Ther 2013;36:527-537)