The morphologic details of the regeneration of the nerve injured under graduated extension

Experiments were made using 80 dogs to study the details of the regeneration of the nerve injured under graduated extension. In group "experiment 1" (n = 22) resection of the sciatic nerve was made as well as its ends were brought closer at the expense of the knee flexion, and microsurgical epineural or epiperineural suture was made; the defect was compensated postoperatively using lengthening of the nerve sutured by gradual changing position in the joint, fixed with the Ilizarov fixator. In group "experiment 2" (n = 27) after osteotomy or resection of the femoral shaft part osteosynthesis was performed using a wire-and-half-pin device, and after that intersection or resection of the sciatic nerve part was performed and also microsurgical suturing was made; distraction was performed postoperatively. Control experiments consisted in filling the resection defect of the nerve with an autologous graft (n = 8) and in suturing by "end-to-end" way after neurotomy without resection (n = 23). The morphologic studies made within the periods from 2 weeks to 2 years after surgery have demonstrated that the effectiveness of the techniques for canine nervous defect filling based on the Ilizarov method is comparable with the results of neurorrhaphy "end-to-end" in defect-free experiments, and in some cases it exceeds them, that should be interpreted as manifestation of the morphogenetic effect of graduated extension. The distraction mini-fascicular regenerate, formed in case of the technique complications, ensures partial morphofunctional recovery comparable with autoplasty results.