Temperature variation and leprosy deformity

An explanation of the selective distribution of the lesion of leprosy is offered on the basis of observations on tissues studied at operation and at autopsy. Tissue damage is not selective with respect to the nature of the tissue affected, and changes themselves vary in degree rather than in kind, which primarily is chronic inflammatory. Freedon from involvement depends on depth from the surface, and therefore on temperature. This explains, for example, why the lining of the nose is so regularly damaged in leprosy; and why the ulnar nerve is so much affected where shallow at the elbow and wrist but not in the forearm where it is covered by a muscle belly. With special reference to nerves, the irregularity of their functional alterations is discussed. All nerves that are paralyzed are superficial, buit not all superficial nerves are so affected. In its early stage paralysis is not due to Wallerian degeneration, but rather to block caused by ischemia, and the ischemia results from inflammatory infiltration. The occurrence and degree of infiltration depend on depth, and more damage occurs in large nerves than in small ones because the latter are apt to be looser and less liable to harmful compression from the swelling. Similar considerations apply to affection of tendons, bones, cartilages, and hair follicles of skin and scalp. Possible effects of climate are discussed. This factor of temperature may be of importance in attempts to cultivate the leprosy bacillus. It may also have limited application in therapy.

The place of reconstructive surgery in the prevention of foot ulceration in leprosy

1- Paralysis of the lateral popliteal nerve in relation to lateral border ulceration is discussed, and three operations used for its correction are described. 2- Paralysis of the posterior tibial nerve in relation to metatarsal-head ulceration is discussed. An operation for the correction of the claw toe deformity is described. 3- Trophic ulceration can only be prevented by careful attention to several factors, namely, (a) reduction of walking and standing to the minimum, (b) reconstruction of paralytic deformities, and (c) use of moulded soles to distribute the weight evenly over the foot.