[Effects of pulsing electromagnetic fields (PEMF) on the course of vertebral fusion callus. A histological study]

In this paper the findings concerning the effectiveness of PEMF on the evolution of the vertebral fusion callus are reported. The study has been carried on by preparing postero-lateral arthrodesis in the lumbar spinal tract in rats. In this tract the laminae have been decorticated, the articular processes prepared by decortication and removal of the articular cartilage, and the spinal processes removed and employed as osteoinductive material. The rats sacrificed after 4 and 8 weeks, show how the decorticated areas are clearly influenced from PEMF, an early appearance of the bony fusion callus is already evident in the treated group just after 4 weeks. Also the articular areas are influenced from PEMF but less markedly than the decorticated one; in these areas after 8 weeks the fusion callus is prevalently cartilaginous even if areas of calcification are detectable inside. This different behaviour can be explained with the absence of any form of spinal fusion by means of surgical tools.