Experimental delayed union of the dog tibia and its use in assessing the effect of an electrical bone growth stimulator.

A technique has been described for the consistent production of delayed bone healing of the tibia in an animal model. A controlled double blind trial, where independent observors did not know the coding of the stimulators and did not collaborate with each other, has evaluated the use of a direct current bone growth stimulator in such an animal model. The conclusion of the experiment is that this commercially available direct current stimulator does produce a significant acceleration of bone healing at 4 weeks in the experimental model used. There is no evidence of inflammatory or neoplastic changes. The eventual clinical role of electrical bone stimulation remains uncertain and many questions remain unanswered, but are promising enough to encourage a controlled clinical trial in situations of disturbed bone healing. Electrical stimulation is apparently safe and appears to significantly augment bone formation. A controlled clinical trial is now being carried out in major medical centers in Australia.