Hooshang Hooshmand, MD, Masood Hashmi, MD, and Eric M. Phillips

Abstract. Cryotherapy (ice application) and deep cryosurgery are commonly employed for neurological, surgical, and physical therapy. Prolonged and repetitive cryotherapy can result in permanent damage to myelinated nerves which are susceptible to myelin coagulation, axonal destruction, and focal somesthetic nerve dysfunction. The stimulation of microscopic perivascular unmyelinated C-thermoreceptornerves (CTN) leads to regional sympathetic nerve dysfunction in the form of neuropathic pain, vasoconstriction, and edema. The cryogenic field is not limited to a small microscopic area. The adjacent intact nerves are susceptible to damage as well, leading to a new source of pain. If, from the beginning, cryotherapy aggravates the pre-existing neuropathic pain, it should be discontinued. An illustrative case is presented.

Descriptors. cryosurgery, cryotherapy, C-thermoreceptor nerves, CTN, neuropathic pain, somatic pain