Roentgenologic Aspect of Certain Lesions of Bone: Neurotrophic or Infectious?

Abstract

“Neurotrophic changes” in bones, especially of the feet, have been reported by several authors. Sante has described the effects of these trophic disturbances of nerves as being most pronounced in the metacarpal and metatarsal bones and the phalanges of the hands and feet. The distal ends of the bones become smaller in caliber and the terminal phalanges are atrophied to fine points. This process of destruction may continue until the heads of the metacarpal and metatarsal bones are completely separated from the distal ends of the shafts. Sante made the further observation that such pronounced osseous lesions are usually accompanied by punched-out trophic ulcers of the soft parts. Shanks, Kerley, and Twining stated that “in certain conditions such as tabes, syringomyelia and leprosy … marked osteolytic changes are often seen in the small bones of the hands and feet. The most typical appearance is a short and pointed phalanx from partial absorption which has commenced at the distal end of the bone.” According to these writers, the condition may be complicated by secondary infection from a perforating ulcer, usually under a metatarsal head. Holmes and Ruggles mentioned a case of diabetes without obvious changes of nerves in which there was shrinkage of the terminal phalanges and erosion of the articular ends of the metatarsal bones. The term “neurotrophic” is used to describe changes in the soft tissue and bone due presumably to some disturbance in the nerve supply to that part. That some type of “neurotrophic” disturbance exists which does lead to soft-tissue changes and which may act to produce trophic ulcers and other lesions of the soft tissues seems to be beyond doubt. In the past, certain lesions of the bone, especially in the feet, have also been ascribed to “neurotrophic” disturbances. These are characterized, as pointed out by Sante, by progressive absorption of the heads of the metatarsal bones and phalanges, decrease of the caliber of these bones, and “pencil-point” deformities of the metatarsals. The purpose of this paper is to investigate the validity of the assumption that these changes are actually the result of “neurotrophic disturbance.” Sixty-one cases, selected because the roentgenograms of the feet showed one or more of the previously defined criteria for the roentgenologic diagnosis of “neurotrophic changes” in bone, have been reviewed. The lesions occurred most frequently among patients from forty-one to fifty years of age, though all ages beyond the first decade are represented (Table I). Thirty-five of the 61 patients were men and 26 were women. Of the 61 patients, only 15 were found to have diseases involving the nervous system (Table II), and in each one of this smaller group, the “neurotrophic” bone changes were associated with an acute or chronic trophic ulcer of the foot (Figs. 1, 2, and 3). The length of time that these ulcers had been present is of interest: