Peripheral Nerve Damage by Cold

WE HAVE studied the histological and clinical effects of low temperatures on the sciatic nerve of the cat. A selective effect on small nerve fibers by chemicophysical means has been previously reported by several workers.1,2 The possibility that cold might selectively destroy large nerve fibers was suggested by the pathological study of colddamaged nerve by Denny-Brown et al.3 In addition, physiological studies during cooling of peripheral nerve by Douglas and Malcolm4 showed selective blockage of small fibers.Interest in nerve damage by cold received considerable stimulus during the 1940's as a result of exposure injuries consequent to the war. Blackwood5 reported findings in 14 cases of immersion foot, mostly in sailors exposed in open boats. He found that immersion for short duration produced less degeneration of axons and myelin than did more prolonged exposures. Blackwood and Russell6 produced degeneration in rat nerves by immersing