How accurate is the instrument they use at the chiropractor that measures heat along the spine to detect subluxations?

WTFK...: Very few of the unusual "instruments" used by chiropractors have been studied sufficiently to draw any conclusions. I suspect they may give some reading that is interpreted in some way by the chiro and factored in to his overall clinical impression. A heat detector per se should be a rather uncomplicated device but it's interpretation and clinical application leaves a lot to be verified.