In an attempt to produce fat embolism of bone experimentally, a catheter was inserted retrograde into the left common femoral artery of twenty-six adult rabbits, with its tip just proximal to the aorto-iliac bifurcation. An average total amount of 1.3 milliliters of Lipiodol (an iodinated neutral fat which has caused fat embolism in human patients when inadvertently introduced intravascularly) was infused continuously for twenty-two minutes.

Magnification of the roentgenograms of the right femur and tibia of undissected animals and also of the decalcified bones revealed minute intraosseous accumulations of embolic fat globules (radiopaque Lipiodol), demonstrable from ten minutes to seven and one-half days after infusion.

A technique was developed to permit fat staining of bone decalcified without dissolving marrow or embolic fat. Sections of the bones were also prepared with a differential Lipiodol stain, since with routine fat stains marrow fat and Lipiodol neutral fat appear identical.

Intraosseous Lipiodol fat emboli were histologically demonstrated for five weeks; they had obstructed subchondral arteries and capillaries of the femoral head especially. Although rare fat emboli were detected at six and eight weeks, they had disappeared at ten weeks.