When looking for a chiropractor to deliver manipulative services it is important to discuss with them their particular beliefs in these questions mentioned earlier. I agree, there is no strong evidence base in the use of manipulation in treatment of disorders such as colic, ear infections, colds, immunity etc,, but there is strong evidence supporting the mechanical effect of manipulation on joint motion, muscle tone and neurophysiological effects. The joints, joint capsules, muscles etc. are full of sensitive proprioceptors, mechanoreceptors and nociceptors which fire during the use of manipulation. This has a strong evidence base. We know, for example, that the spinal division of the trigeminal nucleus extends from the brainstem to about the second or third cervical segment and that afferent neurological input relays here with the trigeminal nerve.
Information is shared here, among other sites.
This is one reason that manipulative therapy can indeed influence head pain and headache, for example. We know that manipulation fires mechanoreceptors which can stimulate inhibitory afferentation at the cord level via the posterior funiculus to the Rexed laminae of the dorsal horn of the cord. This indeed is strongly evidence based and does affect many pain syndromes and subsequent neuromuscular tone. To pigeon hole manipulation or mobilization to strictly biomechanical affect in which joints are freed from hypomobility, is to do this modality a diservice and lacks insight into its full use. I agree, that its use must be carefully assessed by the provider and its use must not be overused for lengthy periods of time without empowering the patient to learn methods of self-management of their problems.