The thenar and hypothenar types of neural atrophy of the hand / by J. Ramsay Hunt.

  • Hunt, James Ramsay, 1872-1937.
Date:
1911
Catalogue details

Licence: In copyright

Credit: The thenar and hypothenar types of neural atrophy of the hand / by J. Ramsay Hunt. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    course of a week or two by distinct wasting of the muscles, which corresponded exactly to the distribution of the thenar branch of the median nerve, as shown in Fig. 6. With the appearance of atrophy, the fibrillary waves ceased and did not recur subsequently. At no time were pain, subjective or objective disturbances of sensation in the hand noted. Some of his colleagues suggested the pleasing possibility of progressive muscular atrophy, but in the course of a few months the scooped out, atrophic depression of the thenar region began to fill in, and at present no difference in the volume of the two sides is apparent. Remarks. The thenar type of neural atrophy of the hand is readily recognized by the characteristic limitation of the atrophy to the abductor pollicis, the opponens pollicis, and the outer head of the flexor brevis pollicis, all of which are supplied by the thenar branch of the median nerve. As the atrophic area is situated between the first metacarpal bone externally and the body of the inner portion of the flexor brevis pollicis, a sharply demarcated depression results, as if the muscular tissue had been scooped out. The electrical reactions vary with the stage and the degree of the atrophic process, and are characteristically neural. Objective disturbances of sensation in the distribution of the median nerve were absent in all of the cases, so that the thenar filaments must have been injured after leaving the main trunk of the median (Figs. 1 and 2). It will be recalled, from the anatomical descriptions, that imme- diately after leaving the main trunk the thenar branch stands in immediate relationship to the palmar border of the anterior annular ligament, beneath which it emerges and over which it passes in a backward and outward direction to its destination in the muscles of the thenar region. The injury to the nerve, therefore, must take place at this point, induced by the continuous or frequently recurring pressure of muscular action. The general usefulness of the hand is not greatly impaired in this type of neural atrophy, except for finer movements, in which the thumb plays an important role, as, for instance, in writing. The first metacarpophalangeal joint may also be considerably weakened anil relaxed as a result of the atrophy. Because of the comparatively slight disturbance of the general power and utility of the hand, the occupation which was instru- mental in the production of the paralysis is sometimes persisted in, and under these circumstances the atrophy may become perma- nent, as in Case II and probably in Case I, although here a slight improvement was apparent after electrical treatment for one year. In Case III the complete restoration of muscular tissue and function is to be attributed to the prompt recognition of the etiological factor and its removal. f lic prognosis in these cases may therefore be regarded as