Diagnosis of pain with a graduated spinal block technique.

The differential spinal examination has been used at Duke University Medical Center for approximately 15 years in the evaluation of low-back and lower extremity pain. This is a technique of using increasing concentrations of procaine hydrochloride to block nerves of various sizes and degrees of myelinization. With the ever increasing number of compensation and liability cases, there is a corresponding need for this type of diagnostic and prognostic test. It is an attempt to give the physician an objective estimate of the pain. It must be stressed that this is just another test for diagnostic and prognostic evaluation. However, initial results seem to indicate that much weight can be placed on the findings in an attempt to objectively categorize the pain as being either organic or functional and whether it is medicated by sensory or sympathetic pathways.