|Budget Amount *help
¥2,600,000 (Direct Cost : ¥2,600,000)
Fiscal Year 2000 : ¥700,000 (Direct Cost : ¥700,000)
Fiscal Year 1999 : ¥600,000 (Direct Cost : ¥600,000)
Fiscal Year 1998 : ¥1,300,000 (Direct Cost : ¥1,300,000)
We evaluated the influences of the delay of the nerve suture, the number of times of nerve suture and the timing of nerve suture on following functional recovery using rats. In I study, we severed the tibial nerve and sutured it with time delay between 0 and 3 months. In II study, we severed the tibial nerve and sutured immediately. Then, after waiting for 1 to 3 months, the same procedure was made at the same site. In III study, we severed the tibial nerve followed by the sural nerve transplantation between the cut ends. In one group both the proximal and distal side were sutured simultaneously, while in another group the distal side was sutured one months later. The evaluation was made after two months of the last nerve suture physiologically and histologically.
In I study, the incidence of the evoked potentials, muscle force and the number of the myelinated nerve fiber decreased significantly in the group with delay of the nerve suture of more than 3 months. In II study, no significant difference was found between 2-months-delay and 3-months-delay suture group in the muscle force. In III study, we cannot see any difference between two groups.
The conclusions are as follows. 1) The nerve repair should be made within 2 months after the nerve injury. 2) Temporary nerve suture is well indicated for the cases where the nerve regeneration takes more than 3 months. 3) The delayed nerve suture of the distal end may not be useful in the nerve transplantation.