Distraction histogenesis of an anastomosed artery.

This study examined the possibility of an adaptive reaction of anastomosed arteries under tension during a distraction lengthening procedure in the tibiae of rabbits. After an osteotomy at the mid tibia, the posterior tibial arteries were transected and anastomosed. Using a pair of small external fixators, the tibiae were distracted at a rate of 0.5mm/day (groups I-IV rabbits). Three weeks after 25% lengthening, the patency and histology of the arteries were examined. Angiography revealed that all of the anastomosed arteries were patent, and intimal hyperplasia was a constant finding. The mean thickness of the intima of the lengthened segment in group I was 60.4 microm, which is 5.0, 3.4 and 2.1 times higher that of the controls in groups IV (un-manipulated arteries, 12.2 microm), III (unlengthened but anastomosed arteries, 17.8 microm) and II (lengthened but untouched arteries, 28.7 microm), respectively. These results show that an anastomosed artery can maintain its patency at a certain level and speed of distraction lengthening. Therefore, it is possible that distraction lengthening and vascular anastomoses can be performed simultaneously provided there is careful monitoring of the circulation.