A measurement of the coefficient of static friction of human long bones

The coefficient of static friction for bone-to-bone contacting surfaces has been measured. Unembalmed human cadaveric tibial and femoral bones were cut with three types of surgical saw, two power driven and one hand held, and the bone-to-bone static friction was determined using an in vitro shear method. It was found that both the type of saw and the type of bone affected the coefficient of friction. Greater coefficients of static friction were found with a coarse cutting saw (the hand-held Gigli saw) and tibial bone which is harder than femoral bone. The findings suggest that a rough surface finish to cut bone, in a well-reduced fracture, should promote healing by stabilizing the fracture interface.