Circulation in corticocancellous bone grafts measured with laser Doppler flowmetry. An experimental study in rats

Laser Doppler flowmetry has been evaluated for measurement of the microcirculation (flux) in corticocancellous bone grafts. Corticocancellous tibial grafts were transplanted between four donor and eight recipients rats of two histocompatibility-mismatched strains. The microcirculations in the grafted and the intact tibias were measured after 12 weeks. Variation of the method in a single animal was 0.3-0.4 in both normal and grafted bone. The flux variation between the animals was of similar magnitude. The variation did not depend upon the magnitude of the flux values. Grafts had between 26% and 53% lower circulation than normal bone, but the graft bone interface, which contained callus, had a 56% higher flux than normal bone. We conclude that laser Doppler flowmetry might be useful in research into bone grafts.