OBSERVATIONS ON PAIN PRODUCED BY INJECTION OF HYPERTONIC SALINE INTO MUSCLES AND OTHER SUPPORTIVE TISSUES

Abstract

The clinical effects of pain experimentally induced by the injn. of hypertonic (6%) soln. of NaCl, as initiated by Kellgren and Lewis, were studied in 18 volunteers subjected to 61 trials. The material was injd. into muscles,[long dash]the scalenus anticus, supraspinatus, trapezius, deltoid, gluteus medium, and the erector spinae; into or about tendons,[long dash]the achilles and insertional biceps; at ligaments,[long dash]the sacroiliac and interspinous and about the knee joint. In some cases the demarcations of pain and tenderness suggested a segmental distr. In most instances these features were irregular and without the definite segmental or recognizable uniform characteristics described by the original observers. Consistent similar effects from stimulation of each of the various selected sites were too infrequent to deduce predictable clinical reaction patterns typical of individual anatomic structures. Our observations on the acute effects of injecting hypertonic saline failed to provide an exptl. basis for such clinical concepts in musculoskeletal pain as "trigger point" mechanisms or specific, diagnostic reaction patterns to identify involvement of individual muscular and other supportive structures.