Time Course of Alterations in Muscle Transfers with Microneurovascular Anastomoses

Abstract

The time course of alterations in muscle transfers with microneurovascular anastomoses was studied in 17 rabbits. The left rectus femoris muscle was transferred to the right side. For comparison, in some animals the right rectus femoris muscle was transferred from the right to the left side, but without vascular repair. Two, seven, 14, 21, and 30 days after transfer, the electric excitability, macroscopic appearance, histology, histochemistry, ultrastructure, and activity of muscle enzymes were assessed. In the transfers with microneurovascular anastomoses, almost all muscle fibers survived. Alterations were limited to those typical of a denervation-reinnervation process. Contrary to this, only a few atrophic fibers survived in the periphery of the transfers without vascular repair. By far, the greater central part underwent necrosis. A considerable amount of connective tissue developed. These results clearly show the functional superiority of microsurgically vascularized muscle transfers over those without vascular anastomoses. Excellent functional recovery is possible because the process of complete degeneration and consecutive regeneration, with inevitable augmentation of connective tissue, is prevented by the performance of vascular anastomoses.

Fiber type morphometry and capillary geometry in free, vascularized muscle transfers

“…Frey has shown that the early denervation and subsequent reinnervation is associated with marked histochemical changes in the first 3 months posttransfer in the rabbit model. 32 Stevanovic et al9 noted focal areas of necrosis comprising about 10-20% of the total area in a dog sartorius model at 3 months of recovery. They speculate that a longer recovery period would be associated with a more normal histochemical appearance.…”

Limits of Muscle-to-Nerve Ratio in Functional Muscle Transplantation

“…17 (c) In free functioning muscle transfers in cases of facial reanimation, the transplants can lead to clinically sufficient results, although the number of reinnervating motor nerve fibers is limited to 20 percent in cross-face nerve transplants. 2,18,19 (d) A selective enlargement of motor units is possible, when muscle fibers are additionally recruited by adjacent motor end plates. (e) Finally, the question arises whether or not a large muscle mass could be a stimulus for nerve sprouting.…”

Three-Dimensional Video Analysis of the Paralyzed Face Reanimated by Cross-Face Nerve Grafting and Free Gracilis Muscle Transplantation: Quantification of the Functional Outcome

“…After the regenerating nerve fibers controlling the function of smiling had grown to the end of the sural nerve graft, free transplantation of the gracilis muscle with microneurovascular anastomoses was performed in a second procedure 10 months later. [12][13][14] In adults dissatisfied with their degree of insufficient eye closure, we used a combination of transposition of the central portion of the temporal muscle to the upper and the lower eyelids to rapidly restore this essential function and thus protect the cornea.…”