ABSTRACT

Early developments in the field of bone cell mechanostimulus were nonquantitative in nature, and date from pioneering work in the 1930s by Glucksmann.

He used biological structures rather than mechanical hardware to apply the loads. One preparation used to load endosteal cell cultures from chick tibiae involved substrates of explanted intercostal muscle to which pairs of adjacent ribs were left attached. Spontaneous compression of the cultured endothelial cells occurred when the ribs were drawn toward one another as a result of degeneration of the muscle tissue. A variant on this approach was to use interposed bone rudiments to serve as barriers to culture mass expansion, thus again inducing compression. Glucksmann also devised a means for biologic delivery of tension, taking advantage of surface tension effects in hanging drop cultures. Subsequently, Bassett and Hermann

refined the hanging-drop tensile loading technique, to study chick tibial cortex culture responses to both mechanical and electrical stimulation. In corollary studies, they modulated culture growth by stretching their culture masses over progressively larger silicone rods during periods of active growth. Compressive load delivery was achieved via autocompaction of culture masses growing between suspension clots. In related experiments,

this group studied

in vitro

piezoelectric responses to flexure of excised long bones with versus without cell viability. Shortly thereafter, Solomons et al.