Abstract
Digit replantation is a complex surgery that nearly always needs to be done as an
emergency. As such it is often difficult to teach. Several models have been developed
to train surgeons in this procedure. We compare three rat models of replantation with
the aim of ascertaining which most simulates the digit replantation. Inbred albino
rats were selected and divided into three groups of 13 each, tail, penile, and hind
replant groups. Three rats in each group were anesthetized, the specific amputation
injury is created and is replanted for the anatomic component of the study. For the
comparative section, 10 animals were anesthesized and the amputated parts were replanted
under standard conditions. The parameters measured included weight, vessels and nerve
diameters, method of fixation, total ischemia and replant times, the patency rates
(after operation and at one week post surgery), as well as postoperative complications.
All rats survived in the procedure. There was patency in all groups immediately. Rat
tail group had 90%, penile group 100%, and hind limb group 90% survival 1 week after
the replantation. There was one mortality in the hind limb group. The penile replant
group was the shortest (p < 0.001), and all vessel sizes were comparable except the central artery of the tail
which was significantly smaller (p < 0.001). The processes of the hind limb group most simulated the human digit replant
procedure, though the ischemia and total replant times are significantly longer (p < 0.005). Though the immediate and 1 week patency rates were similar in all three
groups, the hind limb replantation model involved steps most similar to human digit
replant surgery and is recommended as the preferred teaching model.
Keywords
comparison - rat replantation - models
