Objective To evaluate an effect of the vascularendothelial growth factor (VEGF) geneactivated matrix (GAM) on repair of the sciatic nerve defect in rats. Methods The peripheral nerve extracellular matrix（ECM） was harvested by the chemical extraction from 30 SD rats. The VEGF-GAM comprised of ECM and the plasmids encoding VEGF. Thirty adult Wistar rats were made as a model of the asciatic nerve defect and were randomly divided into the following 3 groups(n=10): Group A (VEGF-GAM conduits), Group B (ECM conduits),and Group C (autografts). At 12 weeks, the rats from each groupwere subjected to an inspection for the walking tract analysis and electrophysiological and histomorphological studies.Results The VEGF DNA could be retained in GAM, promoting the transgene expressing in the sciatic nerve, and more importantly, in the axotomized neurons in the spinal cord for 12 weeks. The motor neuron recovery rate in Group A (79.13％±2.53％) was similar to that in Group C (75.26％±4.48％, Pgt;0.05), but significantly better than that in Group B (56.09％±1.89％, Plt;0.01). The number of the regenerationaxons in the distal sciatic nerve in Group A (13 463±794/mm2) was significantly lower than that in Group C (16 809±680/mm2, Plt; 0.01), but significantly higher than that in Group B (10 260±1 117/mm2,Plt;0.01). The motor nerve conduction velocity in Group A (16.44±1.65 m/s) was significantly lowerthan that in Group C (23.79±2.75 m/s, Plt;0.01), but significantly higherthan that in Group B (12.8 ±1.42 m/s, Plt;0.01). The recovery rate of thegastrocnemius muscle wet weight in Group A (71.40％±3.05%) was significantlylower than that in Group C (87.00％±1.87％,Plt;0.01), but significantly higher than that in Group B (50.00％±4.90％, Plt;0.01). The sciatic nerve function index in Group A （39.37%±4.81%） was significantly lower 〖KG6〗than that in Group C (26.27%±2.71%, Plt;0.01), but significantly higher than that in Group B (4693％±296％, Plt;0.01). Conclusion The results indicate that VEGF-GAM as a bridge can promote the functional recovery of the defected sciatic nerve in rats, but the effect is not so good as that by autografts.
OBJECTIVE: To study the effect of subcutaneous implant of peripheral nerve allograft on sciatic nerve regeneration in rats. METHODS: Out of 30 male Wistar rats, 6 were donors and 24 were divided randomly into 2 groups. In experimental group (group A, n = 12), a 15 mm segment of sciatic nerve harvested from donors was separately inserted into subcutaneous compartment on the right thigh; two weeks later, the segment of sciatic nerve in subcutaneous compartment was removed and transplanted into a 10 mm sciatic nerve defect of left, which was made immediately. In the control group (group B, n = 12), a 10 mm sciatic nerve defect was made and immediately repaired in situ on the left thigh. The regeneration of sciatic nerve was examined histologically (after 2, 4, 8, and 14 weeks) and electrophysiologically (after 14 weeks of operation). RESULTS: After 2 weeks of operation, the inflammatory reaction was a little ber in group A than in group B. After 4 weeks, the intensity of the inflammatory reaction was similar between two groups; some collagen fibers proliferated. After 8 weeks, the inflammatory reaction ended and the collagen fibers proliferated obviously. After 14 weeks of operation, the structure of epineurium was in integrity and there was no obvious difference in perineurium and endonurium between two groups. A large number of myelinated nerve fibers and a small number of unmyelinated nerve fibers regenerated. The structure of myelin sheath was in integrity. The number and size of regenerated axon had no significant difference between two groups(P gt; 0.05). The conduction velocity, the peak value and the latent period of motor nerve were no significant difference between two groups (P gt; 0.05). CONCLUSION: The allograft of sciatic nerve inserted into subcutaneous compartment can promote nerve regeneration.
Objective To explore the method and outcome of knee resurfacing arthroplasty in treating late-staged diffuse pigmented villonodular synovitis (PVNS). Methods Between November 2002 and May 2009, 11 cases of late-staged diffuse PVNS were treated, including 3 males and 8 females with an average age of 51.2 years (range, 42-63 years). The diseaseduration was 2.5-10.0 years (mean, 5.2 years). Unilateral knee was involved in all patients, including 7 left knees and 4 right knees. Nine patients had a history of trauma and 2 cases had no obvious inducing factors. The range of motion was (90.1 ± 17.2)° and Hospital for Special Surgery Knee Score (HSS) was 68.9 ± 8.7. After synovectomy, knee resurfacing arthroplasty was performed in all patients. Results Superficial infection of the incision occurred in 1 case at 6 days postoperatively and was cured after debridement; other incisions healed by first intention. Limited flexion and extension, incomplete palsy of common peroneal nerve, and deep venous thrombosis occurred in 1 case respectively, and were cured or improved after symptomatic treatment. All the 11 cases were followed up 38 months on median (range, 13 to 102 months). Two cases developed chronic pain and were not given treatment. Recurrence occurred in 1 case 12 months postoperatively and recovered after synovectomy again. X-ray films showed no signs of loosening, sinking, and bone destruction. At last follow-up, the range of motion was (109.1 ± 18.6)° and HSS score was 86.7 ± 9.3, showing significant differences when compared with those before operation (P lt; 0.05). According to the HSS score system, the results were excellent in 6 cases, good in 3, fair in 1, bad in 1, and the excellent and good rate was 81.8%. Conclusion A combination of knee resurfacing arthroplasty and synovectomy for the treatment of late-staged diffuse PVNS is able to get a good cl inical results in restoration of function, improvememt of the l ife quality, and decrease of recurrence rate.