[Experimental study on tension and stretching to peripheral nerve].

As to the suturing large peripheral nerve defects under tension, several questions have not yet been answered. How long is the critical gap for functional recovery, and how can these gaps be overcome? In order to resolve these questions, an experimental study was undertaken using sciatic nerves of the 83 mongrel adult dogs. A Two Stage Procedure for the neurorrhaphy was invented to overcome the large nerve defect. This method consists of the following two stages. The first stage operation is done by gradual approximation of both stumps against tension with a single and thick suture material. The second stage operation is done three weeks following the first stage operation, consisting of epineural suture under the microscope after refreshment of both stumps. The longest nerve defect in which axonal regeneration was accomplished by this Two Stage Procedure ranged 5 cm (proximal: 5.2% elongation, distal: 12% elongation) in the sciatic nerve of dogs.