Objective To observe the role of vascular endothelium growth factor (VEGF) in promoting vascular reconstruction and bone repair in the necrotic region of femoral head in rabbits. Methods The femoral head necrosis model was made by liquid nitrogen frozen. The necrotic femoral head was transfected by adenovirus human VEGF121 (Ad-hVEGF121) to observe the bone formation in subchondral necrotic region by means of histological method, measure BMD value by SPA-2 analyser and measure bone trabecular morphology by image analysis. Results Revascularization level, bone formation rate, bone quality and quantity and mineralization level in subchondral necrotic region of gene transfection group were significantly higher than the control groups that had more subchondral bone resorption compared with gene transfection group. Conclusions VEGF may have effect in promoting bone formation and revascularization in subchondral necrotic region of femoral head, indirectly protecting the necrotic bone trabecula from being absorbed and avoiding descending of subchondral mechanics function.

[Objective]To complete comparison between anterior cervical surgery by microendoscopic and open operation,explore feasibility and efficacy of anterior cervical decompression,interbody fusion and fixation by microendoscopic surgery,and give preliminary clinical evaluation of mieroendoscopic surgery.[Method]In a retrospective study,46 patients underwent one level cervical surgery by anterior approach.23 patients(23~64 years,41.5 years in average)were treated with microendoscopic surgery as microendoscopic group.Under general anesthesia,a transverse incision(1.6 cm)was made at right side of neck.A tubular retractor was then inserted and fixed,and a specially designed endoscope was placed inside the tubular retractor.Discectomy and interbody fusion with insertion of Cage or/and plate fixation was performed by endoscope.At fracture and dislocation patient group,titanium Cage was used in 1 case,CBK in 1 case,plate in 5 cases.At cervical disc herniation patient group,titanium Cage was used in 2 cases,CBK in 12 cases,plate in 2 cases.During the same period,23 patients(25~68 years,46.5 years in average)were treated with open surgery as open group.A transverse incision(4～5 cm)was made by right route approach.Discectomy and interbody fusion with Cage or/and plate fixation was performed by general procedure.[Result]At microendoscopic group,23 cases were followed up from 10 to 22 months(16.5 months in average),and mean operative time were 95 minutes,mean blood loss 90 ml.For fracture and dislocation patients,by Frankels classification,2 cases with complete tetraplegia showed no improvement,2 cases with incomplete tetraplegia improved from grade C to grade D postoperatively,1 case upgraded from C to E.For cervical spondylotic myelopathy patients with disc herniation,according to Odoms scoring system,10 cases had excellent outcome,5 good,1 fair.At open group,23 cases were followed up from 8~21 months(15.2 months as average),and mean operative time was 95 minutes,mean blood loss 90 ml.By Frankels classification,2 cases with complete tetraplegia had no improvement,3 cases with incomplete tetraplegia improved from C to D,1 case from D to E.According to Odoms scoring system,8 patients suffering from cervical spondylotic myelopathy with disc herniation had excellent result,6 good,2 fair.[Conclusion]Compared with open surgery,microendoscopic surgery with endoscopic instrument and technique can be used for one level discectomy,interbody fusion and internal fixation,and offer a similar short-term good clinical outcome with minimal incision,less traumatic reaction and postoperative discomfort.

[Objective]To explore the feasibility and efficiency of treatment of lumbar degenerative disease with unilateral decompression,interbody fusion and percutaneous pedicle screw fixation under endoscopic system.[Method]From June 2004 to March 2007,20 patients underwent minimally invasive transforaminal lumbar interbody fusion(TLIF) or posterior lumbar interbody interbody fusion(PLIF),which consisted of 11 male and 9 female patients.The mean age was 46.2 years(range,31～70),and the preoperative diagnosis consisted of postoperative recurrent lumbar disc herniation(n =8),far lateral lumbar disc herniation(n =4),spinal stenosis(n = 3),lumbar instability(n = 3),and discogenic lumbar pain(n =2).One-level decompression and intebody fusion with unilateral pedicle screw fixation under endoscopic system was performed in all of cases(12 at L4、5,and 8 at L5S1).A paramedian,muscle-sparing approach was performed through a tubular retractor docked unilaterally on the facet joint.A total facetectomy was then conducted,exposing and removing the disc(TLIF),or microendoscopic discectomy(MED) was performed(PLIF).The intervertebral space preparation were completed through the X-tube or METRx system.Interbody fusion was achieved with autograft bone and interbody cages.Unilateral pedicle screw-rod placement was accomplished.[Result]There was no conversions to open surgery.Operative time averaged 115 minutes(range,100～165 min).Blood loss averaged 130 ml(range,50～180 ml).Mean length of postoperative hospital stay was 11 days(range,7～15 days).All patients presenting with preoperative low back pain and /or lower extremity radicular pain(n= 20) had resolution of symptoms postoperatively.Complications included two cases of new radiculopathy postoperatively(one from graft dislodgement,the other from hematoma formation).Twenty patients were followed up 10～39 months(average 21.6 months).The preoperative,1 month postoperative and last follow-up Oswestry Disability Index(ODI scores were 42.05+8.36,21.33?6.37 and 12.31?3.75 separately(P

[Objective]To evaluate the early-middle stage clinical results of cervical disc hemiation treatment with the Bryan cervical disc prosthesis.[Method]There were 51 patients with cervical disc herniation.There were 16 female and 35 male patients aged between 31 and 57(mean age 43).The herniated disc was located at C3、4 in 8 cases,C4、5 in 4 cases,C5、6 in 31 cases,C6、7 in 2 cases,C4～6 in 2 cases,C3～6 in 2 cases.and C5～7in 2 case.There were 16 patients with myelopathy and 31 with radiculopathy.A total of 57 sets of Bryan cervical disc prosthesis were implanted,with single level disc replaced in 45 cases and bi-level in 6 cases.The Bryan cervical disc prosthesis contained a proprietary,low-fiction,wear-resistant,unique polyurethane nucleus.The nucleus was located in shaped titanium plates(shells) that include convex porous ingrowth surfaces,to allow bony fixation to the adjacent vertebral endplates.The level of stableness and mobility at the implanting location were observed on dynamic radiograph postoperatively.[Result]The average follow-up was 1 year to 4 and half year.There was no prosthesis displacement and loosening in all cases.One patient had a definite spontaneous fusion of treated segment after 4 years of follow-up.Two patient had grade Ⅱ heterotopic ossification(HO).The range of motion(ROM) at implant level was 9.3 degrees on the flexion-extension radiographs.Significant improvement in neurological symptoms were observed in all cases,and radicular pain for patients suffering from raduculopathy was relieved completely.The average improvement was 8.5 points based on CSM criteria.Effective rate was 100%.[Conclusion]Artificial cervical discs prosthesis provides a new effective treatment for cervical disc herniation.Definite stabilization and satisfactory mobility were achieved after the implantation of cervical disc prosthesis.

Objective To investigate the expressions and role of bone morphogenetic protein(BMP) 2,basic fibroblast growth factor(bFGF),Core-binding factor al(Cbfa1)in the process of pathological bone formation in ankylosing spondylitis.Methods The expressions of BMP-2,bFGF and Cbfa1 in the synovial tissues of AS patients'sacroiliac ioint were detected using in situ hybridization.They were compared with those of patients with hip replacement and the gray scale of cells was analyzed with image analysis.Results The positive expressions of BMP-2,bFGF and Cbfal in the synovial tissues of patients'sacroiliac joint with AS were stronger than those of the control group(P＜0.01).Conclusion BMP-2,bFGF and Cbfal are important factors in the process of pathological bone formation in patients with AS.They areclosely correlated with the process of bone formation in patients'sacroiliac ioint with AS.Reduction of the expressions of BMP-2,bFGF and Cbfa1 with AS can block the process of pathological bone formation.

In order to explore the effect of anti vegf on fracture healing process,rabbits with left radius fracture were used as an animal model and divided randomly into control and experiment groups.VEGF polyclonal antibody was given to the animals of the experiment group films were thken at the fracture sites after 1,3,5 and 8 weeks of the fracture.the results showed that the cellular necrosis increased in the experiment group shortly after the fracture.Although there was fibroblast proliferation at 72 hours after the fracture,continuous focal necrosis was seen from 1 to 5 weeks in the fracture sites,and the vascularization reduced obviously 3 weeks after the injury.The organelle degeneration was observed in the fibroblasts and osteoblasts under microscope.The fracture sites were filled with fibrous tissue at the 8 th week and nonunion was ween in the fracture sites on X ray films.These results suggest that the lack of VEGF in the fracture sites might be one of the important reasons of fracture healing.

Objective To investigate the predictors and characteristics of the surgical outcomes of lumbar discectomy. Methods A total of 204 patients undergoing lumbar discectomy in our hospital from 1985-2003 were selected. The data on the surgical outcomes were collected using questionnaire, communication, and clinical follow-up. The cases were divided into four groups according to the different postoperative time: 1-2, 2-4, 4-8 years, and more than 8 years. The correlated factors in surgical outcomes in the four groups were analyzed by multiple regression analysis. The predictors and characteristics of the surgical outcomes in the four groups were compared. Results The duration between symptom onset and operation was significantly associated with the surgical outcomes. There was no statistical difference in surgical outcomes between the four groups. Conclusion The surgical outcomes of lumbar discectomy are closely associated with the preoperative onset of symptoms and remain unchanged in 2 years after operation.

Objective To observe the effects of inducing ossification in necrotic femoral head by VEGF. Methods Healthy rabbits were lesioned into necrotic femoral head by liquid nitrogen and randomly assigned for AdhuVEGF_(121) gene transfection into the necrotic femoral head and AdTrackCMV transfection. The alkaline phosphatase (ALP) activity before transfection and day 1, week 1, 2, 4, 6, 8, 12 after transfection and the expression of collagen Ⅰ at week 2, 4, 8, 12 was examined by enzymology and immunohistochemical techniques. Results The ALP activity of the AdhuVEGF_(121) group was significantly higher than AdTrackCMV group (P

Objective To investigate the expressions of BMP-2 and bFGF in ankylosing spondylitis(AS)patients in active stage.Methods Five patients with active AS were admitted from July 2006 to March 2007,including 4 males and 1 female,with average age of 31.4 years.Five patients with pelvic fracture served as control,including 3 males and 2 females,with average age of 34.5 years.Using immunohistochemistry,the expressions of BMP-2 and bFGF were detected in the frozen synovial tissues of cacroiliac joint in active AS patients and in the pelvic fracture patients,and the results were compared by analyzing the gray scale of the pictures.Results The positive expressions of BMP-2 and bFGF in the synovial tissues of cacroiliac joint in the patients with active AS were stronger than those in pelvic fracture patients(P

Objective To explore the feasibility of the treatment of special types of lumbar disc herniation using microendoscopic discectomy system(MED-Ⅱ) Methods Posterior interlaminal approach microendoscopic discectomy using the MED-Ⅱ was employed in 53 cases of bi-interspace lumbar disc herniation,75 cases of central type lumbar disc herniation,and 9 cases of extraforaminal lumbar disc herniation.Results All the operations were successfully completed with an operation time of(60~110 min) (mean,70 min) and an intraoperative blood loss of 50~130 ml(mean,70 ml).The length of hospital stay was 5~19 days(mean,13 days).The stitches were taken out at 12 days after operation and the sutured wound healed by first intention in all the cases.Follow-up for 3~8 months(mean,5 months) showed no complications.According to the Nakai classification,there were 40 cases of excellent results,11 cases of good results,and 2 cases of fair in the 53 cases of bi-interspace lumbar disc herniation.Of the 75 cases of central lumbar disc herniation,53,17,and 4 cases were endowed excellent,good,and fair results,respectively,and 1 case got a poor result.Of the 9 cases of extraforaminal lumbar disc herniation,the numbers were 6,2,and 1,respectively.(Conclusions) Use of the MED-Ⅱ for the treatment of special types of lumbar intervertebral disc herniation is effective.