Roentgen Therapy and the Relief of Pain

In describing the properties of x-rays, most authors, when discussing the biological effects, stress the destructive action and make scant mention, if any, of the analgesic effect. When one reads the suggestion, recently made, that a neurosurgeon do a root resection for post-herpetic pain, one wonders if the radiation therapist has not been remiss in failing to call to the attention of his confreres the very wide usefulness of roentgen therapy as an anodyne in a score of crippling conditions. The importance today of roentgen rays as an analgesic has become so convincing, through the successful relief of pain in such afflictions as boils, carbuncles, bursitis, herpes zoster, Marie-Strümpell's spondylitis, and metastatic bone disease that the radiation therapist is impelled to make the treatment of them current practice. Spaced treatments judiciously applied with a total dosage well within the safety range will, in the majority of patients, bring prompt relief from pain. Boils and Carbuncles The analgesic effect of roentgen irradiation is seen strikingly in such relatively mild lesions as boils, as well as in the severe carbuncle where the inflammatory process has spread to the subcutaneous tissue, causing a diffuse infection with toxic absorption. Of 130 hospitalized patients with severe carbuncles treated by x-rays alone or in conjunction with surgery, as previously reported (1), the 60 who received only roentgen therapy were relieved of pain in three to nine hours after the first treatment. The average number of roentgen treatments was three. The average hospital stay for this group was eight and a half days as against thirteen to twenty-one days for the others. Roentgen therapy is just as efficacious today despite the prevalent vogue for chemotherapeutic agents. At the moment only recalcitrant lesions are referred for roentgen therapy. It is well to know that there is no contraindication to the use of x-rays after the use of the sulfa derivatives or penicillin, the latter requiring hospitalization and both giving rise to undesirable sensitization reactions. The obvious explanation of the relief of pain following irradiation in boils and carbuncles lies in the relief of the tension in the tissues caused by stretching of the skin secondary to inflammation associated with inflammatory exudate. Pain quickly disappears as the inflammatory process is resolved, with or without the drainage of pus. Some observations have been made which tend to emphasize a close relation between pain and damage to the cells of the skin rather than damage to pain nerve endings. Lewis (2) believes a histamine-like substance is released by damaged skin cells to give an axon reflex. Histamine, however, when pricked into the skin produces itching but not pain. It is now established that cutaneous pain is subserved by fine medullated and non-medullated nerve fibers bearing free endings. These fibers and endings are specific and arranged in a plexiform interlocking manner described as a “sensory unit,” in contrast to the single afferent nerve ending.