A surgical handbook : for the use of students, practitioners, house-surgeons, and dressers / by Francis M. Caird and Charles W. Cathcart.

  • Caird, Francis Mitchell, 1853-1926
Date:
1889
Catalogue details

Licence: Public Domain Mark

Credit: A surgical handbook : for the use of students, practitioners, house-surgeons, and dressers / by Francis M. Caird and Charles W. Cathcart. Source: Wellcome Collection.

Provider: This material has been provided by The University of Leeds Library. The original may be consulted at The University of Leeds Library.

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    if during healing of the wound care be taken to bandage the stum|) well and keeji the knee flexed, section of the tendo Achillis is seldom necessary. When the stump has healed, the patient bears his weight on what remains of the sole of the foot. At first there may be aching and weakness as the arch of the foot sinks down. Afterwards there will l)e no further troul)le, and the only artificial limb required is a stifl'-soled boot, lacing well above the ankle, and having cork or other stuffing to fill the ])lace of the jiarts of the foot which have been lost. For a Syme's or Pirogoff's amputation, a cheap and useful, though not ornamental, artificial limb consists of a l)ucket ending in a rounded leather end, sufficiently long to equalise the two limbs, and taking its bearing either on the face of the stump or at some of the points, before mentioned, above it. When an artificial foot is desired, the a.xis of movement of the artificial ankle should not be below the level of the stump, as it is usually made, but is more naturally placed slightly above it. Moreover, and what is of greater importance, the face of the stump should rest not on the foot—but on the leg-portion of the artificial limb, which should then be jointed to the foot-part. If this is done, the face of the stump has weight to Ijear, but has no friction. By the usual method—where the stump rests on the foot-piece—friction on the face of the stump is inevitable, and probably explains why so many otherwise good stumps are comparatively useless for the bearing of an artificial limb. (b.) Artificial Ankle- and Foot-Joinls.—Of these there are no end. The first point to understand is—W'hat can an artificial ankle- and foot-joint not do, that a natural one iloes? Next, what may it be expected to do? A minute's reflection will make it plain that no artificial joint can imitate active muscular contraction—e.g., forcible extension of the foot as in rising on the toes, and that the active balancing lateral movements of the foot can never be replaced if the natural mechanism be lost. What can an artificial foot and ankle then do? It can imitate the aj^pearance and ,iw//c of the movements of the original, and permit of a more or less halting gait. Marey, in his analysis of the human step in walking, has shown that the trajectory of the knee of the supporting leg is nearly in a straight line—i.e., that the knee joint neither rises nor falls as the leg passes from the position directed obliquely backward (as the heel comes down), through the vertical, to that sloping obliquely forwards as the toe leaves the ground. Owing to the active muscular changes at the ankle-joint, this is attained with a longer stride than would be otherwise possible. Without such an actively changing ankle and foot, the stride must be less, but the same straight-line-lrajectory of the knee can be obtained by ensuring that the leg from the knee downwards rolls forward on a sole, curved in the arc of a circle whose centre is at the knee-joint, and whose radius is equal to the distance between the knee and the sole of the Ijoot. This produces the same eflcct as if the knee were the axle of a wheel and the sole of the foot part of the circumference. This curve of sole is