Diseases of the nervous system : a text-book for students and practitioners of medicine / by H. Oppenheim, translated and edited by Edward E. Mayer.

  • Oppenheim, Hermann, 1858-1919.
Date:
1904
Catalogue details

Licence: In copyright

Credit: Diseases of the nervous system : a text-book for students and practitioners of medicine / by H. Oppenheim, translated and edited by Edward E. Mayer. Source: Wellcome Collection.

    37/994 (page 33)
    Fig. 12. Pes valgus produced by secondary contraction of the peroneus longus muscle. Foot viewed from the outer side. thus decreasing the size of the anterior Fig. 13. The triceps surse (gastrocnemius, plantar is, and soleus) promote plantar flexion 1 and adduction of the foot. The foot also will be so turned that the dorsal surface looks outward. In simple plantar flexion the pero- neus longus is also ealh-d into action. Its action is more forcible with extended knee (the gastrocnemius, which is inserted into the femur, slightly bends the knee) ; when the lower leg is bent upon the thigh, the soleus acts alone. In paralysis of the triceps surae flexion of the foot is almost impossible, and is never more than ninety degrees. The peroneus longus draws the first metatarsal downward, and causes valgus. (Fig. 12.) Gradually, through the extensors (the dorsal flexors), a liatchet-foot is produced. Contracture of the antagonists, however, does not always follow. The patient cannot raise himself upon his toes; walking is difficult for him. A secondary shorten- ing of the muscles and fasciae of the plantar region follows,—and, resulting therefrom, a marked arch- ing of this region. The peroneus longus has little to do with exten- sion of the foot; it is especially an abductor. It depresses the inner and elevates the outer border, and draws the head of the first metatarsal downward and outward, foot and increasing thereby the arch of the foot. In paralysis of this muscle, exten- sion of the foot takes place with adduc- tion ; the inner side of the front part of the foot is not supported any longer, and sinks from the pressure. In walking the foot only touches the floor with the outer border; the head of the first meta- carpal is raised from the floor and the great toe is strongly flexed. The plan- tar arch decreases from standing, a flat- foot condition resulting. Walking is fatiguing; standing on the toes is not possible, or uncertain. Pressure in walking upon the nerves of the plantar surface produces pares- thesia and pain. The tibialis anticus, extensor longus digitorum, and extensor hallucis longus produce extension of the foot. The tibi- alis anticus is at the same time an adduc- tor; it draws the head of the first meta- tarsal upward and inward and lifts the inner border of the anterior part of the foot (at the same time the toes, espe- cially the great toe, being flexed). The extensor longus digitorum extends the four toes slightly, but it is especially an extensor of the foot; it also lifts the outer border Position of the feet in paralysis of the extensors of the feet and toes, “ foot-drop.” 1 Plantar flexion will be denoted as flexion, dorsal flexion as extension. 3