A different approach led to the substitution of a "great toe" silastic joint prosthesis for the thin "nipple" prosthesis. The great toe prosthesis met with significant success because it was substantially thicker at its base, and could therefore survive more prolonged wear and tear.
The great toe prosthesis was placed in the base of the first metacarpal. Perhaps because it necessitated removing both apposing joint surfaces and eliminated contact of the silastic with cartilage, reaction ("silastic synovitis") was averted. The stem of the great toe prosthesis was shortened to one centimeter to allow for possible fusion of the first metacarpal with the trapezium in the advent of fatigue fracture and failure of the prosthesis. Since the surface was concave and not convex, the trapezium was flattened to allow placement of this prosthesis on a stable surface.
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