PAIN FROM DERMAL, PERIOSTEAL, AND FASCIAL ENDINGS AND FROM INFLAMMATION

Abstract

THE OBJECTIVE of this investigation was the examination of dermal, subdermal, fascial, and periosteal pain endings accessible from the surface of the body and a comparison of these with the better-known pricking-pain endings located subepithelially. Criteria for comparison were the subjective sensations evoked by comparable stimuli to the skin surface, to deep endings, or to nerves supplying these endings in their course below the skin; the spatial distributions of endings, and the relative thresholds—and therefore the fiber-size groupings— of the nerve fibers mediating the different sensations. Size groups of fibers innervating pain endings were determined by applying differential-pressure and procaine blocks to the peripheral nerves supplying the various sensory endings of the hand, arm, and leg of the human subject. We served as subjects, after considerable training in the discrimination of the effects of painful stimulation of various sorts. Deep endings have been studied recently, by means of mechanical stimulation,