Degeneration and regeneration of the nervous system

http://jbjs.org/content/jbjsam/72/4/637.3.full.pdf

Bone Tumors. Clinical, Radiologic, and Pathologic Correlations.

This study was performed to determine whether vein grafts might serve as a conduit for nerve regeneration. A 1 cm segment of sciatic nerve was removed bilaterally in 12 Sprague-Dawley rats. On one side the gap was not repaired, and on the other side a segment of femoral vein was used to bridge the nerve gap. Nerve conduction studies and necropsies were performed at intervals. Reconstitution of nerve trunk continuity and healing of plantar ulcers occurred only in the vein-grafted side. Histologic examination revealed orderly growth of nerve fibers within the lumen of the vein grafts as early as 1 month after repair. Most regenerating nerve fibers passed through the proximal junction in an orderly pattern and reached the distal stumps within 2 months after repair. Results of nerve conduction study at 4 months after operation demonstrated restoration of conduction through the vein-grafted sciatic nerves with muscle reinnervation. Nearly normal muscle fibers in the gastrocnemius on the repaired side were confirmed at necropsy. This study demonstrated that autogenous vein grafts can serve as a conduit for nerve regeneration in rodents.

Autogenous vein graft as a conduit for nerve regeneration

Nerve guide conduits for peripheral nerve injury repair: A review on design, materials and fabrication methods.

Biomaterials and cells for cardiac tissue engineering: Current choices.

With significant advances in the research and application of nerve conduits, they have been used to repair peripheral nerve injury for several decades. Nerve conduits range from biological tubes to synthetic tubes, and from nondegradable tubes to biodegradable tubes. Researchers have explored hollow tubes, tubes filled with scaffolds containing neurotrophic factors, and those seeded with Schwann cells or stem cells. The therapeutic effect of nerve conduits is improving with increasing choice of conduit material, new construction of conduits, and the inclusion of neurotrophic factors and support cells in the conduits. Improvements in functional outcomes are expected when these are optimized for use in clinical practice.

/pdf/past-present-and-future-of-nerve-conduits-in-the-treatment-1w0zckiwn8.pdf

Past, Present, and Future of Nerve Conduits in the Treatment of Peripheral Nerve Injury.

Treatment of spinal cord injury has always been a challenge for clinical practitioners and scientists. The development in stem cell based therapies has brought new hopes to patients with spinal cord injuries. In the last a few decades, a variety of stem cells have been used to treat spinal cord injury in animal experiments and some clinical trials. However, there are many technical and ethical challenges to overcome before this novel therapeutic method can be widely applied in clinical practice. With further research in pluripotent stem cells and combined application of genetic and tissue engineering techniques, stem cell based therapies are bond to play increasingly important role in the management of spinal cord injuries.

Stem cell based therapies for spinal cord injury.

In the current research, to find if the combination of chitosan nerve conduits seeded with autologous bone marrow mononuclear cells (BM-MNCs) can be used to bridge 30 mm long peroneal nerve defects in goats, 15 animals were separated into BM-MNC group (n = 5), vehicle group (n = 5), and autologous nerve graft group (n = 5). 12 months after the surgery, animals were evaluated by behavioral observation, magnetic resonance imaging tests, histomorphological and electrophysiological analysis. Results revealed that animals in BM-MNC group and autologous nerve graft group achieved fine functional recovery; magnetic resonance imaging tests and histomorphometry analysis showed that the nerve defect was bridged by myelinated nerve axons in those animals. No significant difference was found between the two groups concerning myelinated axon density, axon diameter, myelin sheath thickness and peroneal nerve action potential. Animals in vehicle group failed to achieve significant functional recovery. The results indicated that chitosan nerve conduits seeded with autologous bone marrow mononuclear cells have strong potential in bridging long peripheral nerve defects and could be applied in future clinical trials.

/pdf/chitosan-nerve-conduits-seeded-with-autologous-bone-marrow-4jni9f1maf.pdf

Chitosan nerve conduits seeded with autologous bone marrow mononuclear cells for 30 mm goat peroneal nerve defect.

Background Despite great advances in aseptic surgical techniques, surgical site infection (SSI) is still one of the main complications after spine surgery. SSI can bring tremendous physical, psychological, and economic challenges to patients. Intrawound vancomycin application is a much disputed method for the prevention of SSI after spine surgery. Objective The aim of this study is to review the current literature for studies on the intra-wound application of vancomycin powder and to analyze its effectiveness in the prevention of postoperative SSI. Methods PubMed, Medline, Elsevier, and CNKI were searched for the key words "vancomycin", "local/intraoperative/topical/intra-wound", "spine/spinal/lumbar/cervical/thoracolumbar surgery", "infection", and "SSI" in published studies on the effectiveness of intrawound vancomycin application to prevent postoperative SSI. RevMan 5.3 was used to compare the data extracted from the studies included. Results A total of 27 studies involving 17,321 patients were included in the final analysis. Among those patients, 7,423 patients were treated with vancomycin to prevent SSI, with 9,898 in control groups. SSI incidence after surgery in experimental groups was 0.39 times as high as control groups, and this difference was statistically significant (P<0.01). Among patients who underwent internal fixation, vancomycin application significantly reduced the incidence of postoperative SSI (OR 0.31 95% CI 0.19-0.50; P<0.01). Meanwhile, vancomycin did not affect SSI incidence in patients who did not receive internal fixation (P=0.17) or received deformity correction (P=0.25). Conclusion SSI incidence after spinal surgery can be significantly reduced by intrawound application of vancomycin in most circumstances. This method can be applied in various spinal procedures involving instrumentation to prevent postoperative SSI.

/pdf/effect-of-intrawound-vancomycin-application-in-spinal-1et17heb5p.pdf

Effect of intrawound vancomycin application in spinal surgery on the incidence of surgical site infection: a meta-analysis.

Percutaneous vertebroplasty vs balloon kyphoplasty in the treatment of newly onset osteoporotic vertebral compression fractures: A retrospective cohort study.

Aikeremujiang Muheremu

Papers

Past, Present, and Future of Nerve Conduits in the Treatment of Peripheral Nerve Injury.

Stem cell based therapies for spinal cord injury.

Chitosan nerve conduits seeded with autologous bone marrow mononuclear cells for 30 mm goat peroneal nerve defect.

Effect of intrawound vancomycin application in spinal surgery on the incidence of surgical site infection: a meta-analysis.

Percutaneous vertebroplasty vs balloon kyphoplasty in the treatment of newly onset osteoporotic vertebral compression fractures: A retrospective cohort study.