Observations on the early mechanisms of severed nerve regeneration after compressive tubulation repair.
A moderately compressive tubulation procedure has been devised to improve regeneration that follows fascicular neurorrhaphy. The early phases of the regenerative process were analyzed to identify the underlying cellular mechanisms. Adult Sprague-Dawley rats were subjected to bilateral fascicular neurorrhaphy involving tubulation on one side with a dura mater sheet closely apposed to the suture site. One to 16 days postoperatively the nerves were processed for histological analysis. Compared with nontubulated nerves, the cuffed side displayed a longer extent of retrograde myelin and axonal degeneration, a faster rate of orthograde remyelination, axonal invasion of the suture plane at about the same period (fifth postoperative day), larger contingent of regenerating fibers invading the distal stump, more longitudinally oriented fibers at the repair level, no escape of regenerating fibers into the extraneural tissue through the repair borders, and less intraneural edema. These findings have implications for the potentially beneficial effects of mechanically restricting post-traumatic intraneural edema buildup during nerve regeneration.
D000818:Animals; D001369:Axons / Q000502:physiology; D004388:Dura Mater / Q000502:physiology / Q000601:surgery; D009416:Nerve Regeneration; D010525:Peripheral Nerves / Q000473:pathology / Q000502:physiology* / Q000601:surgery; D051381:Rats; D011919:Rats, Inbred Strains; D012584:Sciatic Nerve / Q000502:physiology / Q000601:surgery