Manual of artificial limbs : copiously illustrated : artificial toes, feet, legs, fingers, hands, arms : for amputations and deformities, appliances for excisions, fractures, and other disabilities of lower and upper extremities : suggestions on amputations, treatment of stumps, history, etc., etc., etc. : an exhaustive exposition of prosthesis.

  • Marks, George E. (George Edwin), 1853-1932.
Date:
1912
Catalogue details

Licence: Public Domain Mark

Credit: Manual of artificial limbs : copiously illustrated : artificial toes, feet, legs, fingers, hands, arms : for amputations and deformities, appliances for excisions, fractures, and other disabilities of lower and upper extremities : suggestions on amputations, treatment of stumps, history, etc., etc., etc. : an exhaustive exposition of prosthesis. Source: Wellcome Collection.

Provider: This material has been provided by the Francis A. Countway Library of Medicine, through the Medical Heritage Library. The original may be consulted at the Francis A. Countway Library of Medicine, Harvard Medical School.

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    HOW WE WALK On Natural Feet.—No two persons walk exactly alike. Every- one carries his mannerisms in his steps. The way in which he lands on his heel, rolls on the sole, lifts on the ball, throws himself to the right or the left, the uniformity and regularity of each joint's action, the angle at which the hip is checked, the range of articula- tion permitted in the knee and the angular motion of the ankle,— all form a part of his individuality and make it possible to dis- tinguish a friend from a stranger long before his features have come within the reach of vision. All sorts of forces—heredity, early habits, occupation, disease, injuries, and age—influence the movements of the leg and foot. A man in good health walks dif- ferently from an invalid, a farmer can be distinguished from a merchant, a bookkeeper from a railroad conductor, the sprightli- ness of youth, the infirmities of age are reflected in every step that is taken. Yet there are certain facts connected with walking that are common to all and which can be ascertained by observation and study. These facts are so universal that they become laws govern- ing locomotion; they form a necessary part of the limb-maker's education, and unless he is familiar with them and applies them thoughtfully to the construction of artificial limbs, he is not com- petent to work out the problems that are continually arising. As this work is designed as a text-book on artificial limbs, it is essential, at the outset, to present the cardinal facts relating to natural walking, in order that the application of them to artificial aids may be clearly understood and appreciated. Kinetoscopic photography affords the most valuable aid to an investigation of the actions of the knee and ankle joints when performing their functions. It shows that when a man walks slowly, say two miles an hour, the knee flexes but slightly and the ankle considerably. When walking three miles an hour, the knee joint acts through a greater range and the ankle joint through a lesser one. When walking moderately fast, say four miles an hour, the knee action becomes considerable and the ankle action scarcely perceptible. When walking rapidly, say five miles an hour, the knee action is increased and the ankle becomes prac- tically rigid. When running the knee increases its activity, and the ankle reverses its action and throws the man forward by the ball of the foot. The ratio that exists between the range of motion of the knee and that of the ankle is in proportion to the speed with which one moves. An impulse is had to walk slowly or rapidly, or to change