A COMPARISON OF IMMEDIATE AND DELAYED NERVE REPAIR USING AUTOLOGOUS FREEZE-THAWED MUSCLE GRAFTS IN A LARGE ANIMAL-MODEL - THE SIMPLE INJURY

Freeze-thawed muscle grafts (FTMG) have been suggested as an alternati ve to nerve grafts in reconstruction of peripheral nerve defects. This study compares the results of immediate and delayed nerve repair with freeze-thawed muscle graft in a large animal model. Under general ana esthesia, ten adult sheep underwent excision of 3 cm of the right medi an nerve. Five had immediate nerve reconstruction with FTMGs (Group A) and five were repaired after 4 weeks (Group B). At 6 months, both the right (repaired) and left (''control'') median nerves of each sheep w ere assessed. Nerve blood flow distal to the graft in both groups of r epaired nerves was approximately 60% of that in their respective contr ol nerves. Peak nerve conduction velocities were significantly slower in the repaired nerves. The mean fibre diameters of the immediate and delayed repairs were 5.06 and 3.90 mu respectively compared to a contr ol mean of 8.58 mu G-ratios confirmed that the repaired nerves in both groups were well myelinated. The authors conclude that the FTMG can b e used in delayed as well as immediate nerve reconstruction with minim al impairment of final results.