Defects of sixteen peripheral nerve were re-paired by skeletal muscle bridging from December1986 though December 1989. Satisfactory resultswere achieved after follow-up for 8-31 months.The key point of this operation were proper explo-ration and exposure of the nerve stumps ,thoroughresection of the cicatricial tissues from the stumpsproper chois of muscular fascicle for bridging, pro-viding a good blood supply to the muscle strip, andcorrect suture of the nerve under microscope. Irri-gation of the operativ field with hydrocortisone could play some roles of decreasing the postoperative local inflammation,edema,adhesion, and scar formation.
In this experiment ,the sciatic nerves or twen-ty-eight rats were cut and then anastomosed withbiological adhesive agent or by suture in randonand the latter as control. The biological adhesive a-gent from human plasma was composed of fibrino-gen coagulase and medullary sheath of the nervetaken at the anasomosis region were studied histol-gically. The results of the experimental group wsasignificantly superior to the control.
Objective To comment on the recent advances of production and application of the bio-derived scaffold in the tissue engineered peripheral nerve. Methods The recent articles were systematically analyzed, and then the production methods of the bio-derived scaffold and its application to the tissue engineered peripheral nerve were evaluated and prospected. Results B iological tissues were processed by some methods to produce the bio-derived materials. These mat erials could maintain the structure and components of the tissues. Moreover, the immunogenicity of these materials was reduced. Conclusion Application of the bio-derived materials is a trend in the fabricating scaffold of the tissue en gineered peripheral nerve.
In order to verify the effectiveness of neural stump buried into the muscle in the prevention and treatment of neuroma, 17 cases were reported, in which 8 cases having 19 painful neuromas and 9 cases having 13 amputated meural stumps, buried into muscle. They wese followed up for 6 months to 40 months, It was shown that good and excellent results were obtained and no evidence of neuroma was observed in all cases except in one which had painful neuroma occurred from the failure of embedment of the neural stump into the muscle. The conclusion was that the neural stump buried into muscle was an effective method for the prevention and treatment of neuroma.
The biomaterial, chitin, was used to create a nerve regeneration chamber for bridging healing experiment of sciatic nerve of rats having a defect of 12mm. The crude Schwann cells were introduced into the chambers in one group and the other group had no crude Schwann cells in the chamber and the results of the two groups were compared with those having the nerve defects bridged with skeletal muscles. The specimens were observed by macroscopic, microdissection. electrophysiologic testing, HRP retrograde labelling, histologic and electron microscopic examinations at 4, 8, and 12 weeks after the operation. The results showed that atthe 8th week, the regenerating nerve fibers from the cephalad ends had united with the fibers of the caudal ends of the divided nerves either the crude Schwanneclls were introduced or not, but the morphology of the regenerating nerve, the way of regeneration and the recovery of the function of the extremities were far superior in the group that no cruds Schwann cells had been introduced than those with crude Schwann cell introduced and those bridged by skeletal muscles.
A controversy still exists in the management of nerve injection injury. The results of different timing of operation and methods in treating this type of nerve injury were analysed in limb s function, neuroelectrophysiology and histology. The results showed that the recovery of the injuried nerve in the group of operation, was considerably better than that in the group without operation. In the group of operation early incision of the epineurium with saline irrigation! was superior to late neurolysis. It was suggested that the early incision with saline irrigation could be used as an emergency management for this type of nerve injury.
Objective To explore effects of several immunosuppressants on cytokine expressions after repair for a sciatic nerve injury in a rat model. Methods The sciatic nerves of 42 rats were cut and suturedend to end. After operation, the rats were divided into 6 groups. Group A(n=9) was served as a control with no medicines given. Group B (n=9) was given methylprednisolone 20 mg/(kg·d) for 2 days. Groups C(n=9) and D(n=3) were given FK506 1 mg/(kg·d) for 2 weeks and 4 weeks respectively, and were given the same doses of methylprednisolone as Group B. Groups E and F were given CsA 2 mg/(kg·d) for 2 weeks and 4 weeks respectively, and were given the same doses of methylprednisolone as Group B. The sciaticnerves were sampled at 1, 2 and 4 weeks postoperatively. And immuneohistochemistry stainings of interleukin 1β(IL-1β)， tumor necrosis factor α(TNF-α), interferon γ(IFN-γ) and macrophage migration inhibitory factor(MIF) were performed. The staining results were compared and analyzed. Results The expression peaks of IL-1β and IFN-γ were found at the 1st week postoperatively in Group A. Then, the expression decreased rapidly at the 2nd week and disappeared at the 4th week. As for TNF-α and MIF, they were only found to have a low expression until the 1st week in Group A. In groups C-F, the expression peaks of IL-1β, TNF-α and IFN-γ were found at the 2nd week, while the expression peak of MIF was still at the 1st week, and the expression of all the cytokines extended to the 4th week. The expressions of these cytokines in Group B were just between the expression levels of Group A and Groups C-F. Conclusion Immunosuppressants can delay the expression peaks and significantly extend the expression time of IL-1β, TNF-α, IFN-γ and MIF after repair for a sciatic nerve injury in a rat model.
OBJECTIVE: To explore the possibility to bridge peripheral nerve defects by xenogeneic acellular nerve basal lamina scaffolds. METHODS: Thirty SD rats were randomly divided into 5 groups; in each group, the left sciatic nerves were bridged respectively by predegenerated or fresh xenogeneic acellular nerve basal lamina scaffolds, autogenous nerve grafting, fresh xenogeneic nerve grafting or without bridging. Two kinds of acellular nerve basal lamina scaffolds, extracted by 3% Triton X-100 and 4% deoxycholate sodium from either fresh rabbit tibial nerves or predegenerated ones for 2 weeks, were transplanted to bridge 15 mm rat sciatic nerve gaps. Six months after the grafting, the recovery of function was evaluated by gait analysis, pinch test, morphological and morphometric analysis. RESULTS: The sciatic nerve function indexes (SFI) were -30.7% +/- 6.8% in rats treated with xenogeneic acellular nerve, -36.2% +/- 9.7% with xenogeneic predegenerated acellular nerve, and -33.9% +/- 11.3% with autograft respectively (P gt; 0.05). The number of regenerative myelinated axons, diameter of myelinated fibers and thickness of myelin sheath in acellular xenograft were satisfactory when compared with that in autograft. Regenerated microfascicles distributed in the center of degenerated and acellular nerve group. The regenerated nerve fibers had normal morphological and structural characters under transmission electron microscope. The number and diameter of myelinated fibers in degenerated accellular nerve group was similar to that of autograft group (P gt; 0.05). Whereas the thickness of myelin sheath in degenerated accellular nerve group was significantly less than that of autograft group (P lt; 0.05). CONCLUSION: The above results indicate that xenogeneic acellular nerve basal lamina scaffolds extracted by chemical procedure can be successfully used to repair nerve defects without any immunosuppressants.