BACKGROUND: Tendon transplantation is limited by deficiency of donor tendon or immunological rejection. With the development of cell culture and transplantation techniques and biomaterial science, tissue-engineered tendon, a novel ideal tendon substitute, can be used to repair tendon defect. OBJECTIVE: To summarize the research course and novel advances of tissue-engineered tendon. RETRIEVAL STRATEGY: A computer-based online search of PubMed database was undertaken to identify related English articles published between January 1994 and December 2007 with keywords "tissue engineering, artificial biocompatible tendon". In addition, we searched Wanfang database for related Chinese articles dated from January 1994 to December 2007 with the same keywords in Chinese. Eighty articles were collected from the above-mentioned databases, including 55 Chinese and 25 English. Only ①original articles with reliable argument, ②articles with clear viewpoints, and ③articles strongly correlated with the objective of the article were selected. Eight articles with unrelated content and 40 repetitive studies were excluded. LITERATURE EVALUATION: Thirty-two articles accorded with the inclusive criteria were included, including 10 animal experiments and in vivo, ex vivo and cytology experiments, 12 review articles, comments and lectures, and 10 clinical studies. DATA SYNTHESIS: Tendon injury not treated promptly may result in limb disturbance. Tissue-engineered tendons can repair the appearance and rebuilt the function of injured tendon, and serve as permanent substitutes. Currently, although tissue engineering is developing rapidly, there are still many problems in clinical application. Firstly, seed cells cannot only be harvested from autologous tenocytes. Secondly, how to improve materials to become ideal three-dimensional scaffold material for constructing organ, and how to simulate body environment to construct tendon tissue in vitro are still uncertain. CONCLUSION: Using bioreactor to simulate body environment to construct tissue-engineered tendon is future research focus.

[Objective]To detect the predictors of residual low back pain (LBP) after laminectomy.[Method]From 1996 to 2000,69 cases (31 males and 38 females) of degenerative lumbar stenosis who had underwent laminectomy treatment and with at least 5 years' follow-up documents were involved in this study.LBP were evaluated by the Japan Orthopedic Association (JOA) Scoring System (3 points) pre- and post operation.The relationship between the patients' outcomes and all these clinical and radiographic parameters were analyzed by software package SPSS 13.0.[Result]Twenty-two cases were classified as residual LBP group(group 1) and 47 cases as no-residual LBP group(group 2),binary logistic regression analysis indicated that the predictors of residual LBP were preoperative lumbar lordosis angle、ROM and the number of decompressed laminae.The forward comparison revealed that the lumbar lordosis (22.27??3.12?) and ROM (22.91??2.31?) in group 2 were lower than the lordosis angle (37.23??2.19?) and ROM (31.66??1.52?) in group 1,but the number of decompressed laminae of group 2 (2.77?0.19 ) were higher than that in group 1(1.70?0.10 ) significantly,the P values were 0.000、0.002 and 0.000 respectively.[Conclusion]Residual LBP may attribute to the decrease of compensation ability to the postoperative instable tendency on a more flat and inflexible lumbar spine especially for multi-laminectomy,so that more attention should be paid to these kind of patients to avoid the development of refractory residual LBP.

[Objective] To evaluate the efficacy and short-term results of selective expansive open-door laminoplasty(ELAP).[Method] From June 2005-June 2006,a total of 102 pataents with cervical spondylotic myelopathy(CSM)were enrolled in this study.Forty-four patients underwent ELAP.Fifty-eight patients undergoing conventional C3~7 ELAP served as controls.The clinical results and radiological examinations of both groups were evaluated at 12 month after surgery.[Result]There was no significant difference in recovery rate of Japanese Orthopaedic Association(JOA)scores.The incidence of axial symptoms in the selective ELAP group was significantly lower than those in the C3~7 ELAP group(P

[Objective]To evaluate the efficacy and short-term results of FASTIN anchor in cervical expansive open-door laminoplasty(ELAP).[Method]From February 2005 to February 2006,a total of 89 cases of cervical spondylotic myelopathy(CSM) were assessed in this study.Forty patients undergoing expansive open-door laminoplasty(ELAP) by FASTIN anchor were classified as study group.Fouty-nine patients undergoing conventional ELAP served as controls.The clinical results and radiological examinations of both groups were evaluated at 24 months after surgery.[Result]There were no significant differences in operation time,bleeding quantity and recovery rate of Japanese Orthopaedic Association(JOA) scores.The incidences of axial symptoms and C5 palsy in the study group were significantly lower than those in the control group(P

[Objective]To study the clinical characteristics of osteochondrosis of lumbar posterior vertebral edge(OLPV) and evaluate the efficiency of surgical treatment. [Method]From August 2000 to August 2003,41 cases of OLPV patients were treated,all cases underwent decompression of posterior approach and selective resection of the compressive things.Furthermore,1 case was treated with trans-vertebral pedicle internal fixation and inter-transverse process bone graft because of excessive decompression and preoperative lumbar instability.[Result]Low back and leg pain disappeared or obviously being relieved in all cases,and the results of histological analysis suggested the diagnosis of OLPV in all cases.Forty-one cases were followed from 5 to 8 years,average 6.8 years.No lumbar instability or spondylolisthesis was found in any case.Six cases suffered slight low back pain occasionally without obvious impaired quality of life.The preoperative JOA score was 14.73?2.06,when followed by 3 months,the score changed into 27.14?4.13,there was statistical significance between them(P

Objective To study the causes of hematoma-induced spinal cord injury after surgical treatment of fluorosis cervical canal stenosis (FCCS) so as to conclude the methods for early diagnosis and treatment.Methods A retrospective review was conducted on 329 cases of FCCS undergone expansive laminoplasty (ELOP) between 2006 and 2009.Eighteen out of the 329 cases presented with neural deterioration in postoperative 2 weeks,including l 1 males and 7 females at age of 45-73 years (mean 56.9 years).MRI scan at postoperative 1-5 days confirmed that the injury cause was hematoma formation (incidence of 5.47％).Once the definite diagnosis was made,immediate local puncture decompression,immobilization in the prone position as well as a timely second surgical probe and spinal decompression were performed.Results Nerve symptom of the 18 cases obtained different degree of recovery.Japanese Orthopedic Association (JOA) score promoted from preoperative (7.44 ± 1.25) points to (12.6 ± 2.1)points at 12 months after second operation.Scatter plot between time of definite diagnosis and improvement value in JOA score before and after the second operation was drawn so as to establish linear equation (Y =6.240 7-0.777 8X(F =9.89,P ＜0.01).As a result,the two variables presented a negative linear relationship,which suggested a better outcome after early treatment than delayed treatment.Conclusions Hematoma compression is the main cause of spinal cord injury following operation for FCCS patients.Strict hematosis and alternate lateral clinostatism after operation were effective prevention methods.Besides,early diagnosis and timely treatment are critically important.

Objective To study the spinal neurocyte apoptosis and the changes of p53 in chronic fluorosis rats,and the improvement after drinking no fluoride water.Methods One hundred twenty Wistar rats were divided into 4 groups by random number table method according to body mass,30 rats in one group fed with high concentration NaF water (200 mg/L) to make fluorosis model and classified as high fluoride group;other 30 rats were fed with distilled water as control group;another 30 rats were fed with high concentration NaF water (200 mg/L) for 12 weeks,then fed with distilled water for 12 weeks and classified as defluorination group;the rest 30 rats were classified as defluorination control group.The content of fluoride in urine was tested after the 4th,8th,and 12th weeks.Then the content of fluoride in urine of defluorination group and defluorination control group was tested.The high fluoride group rats and control group rats were killed after 12th week.Defluorination group rats and defluorination control group rats were killed after 24th week.Their spinal cord was collected.The expression of p53 protein in spinal cord was detected by immunohistochemistry and Westem blotting.Apoptosis of the neurocyte was quantitatively analyzed by flow cytometry (FCM).Results By FCM,apoptosis of neurocyte was increased in both high fluorosis group rats and defluorination group rats compared with those in control group rats [(3.36 ± 0.71)％ vs.(0.78 ± 0.65)％;(3.47 ± 0.56)％ vs.(0.83 ± 0.64)％,t =14.680,17.003,all P ＜ 0.01)],but no difference was found between these two groups [(3.47 ± 0.56)％ vs.(3.36 ± 0.71)％,P ＞ 0.05)].Immunohistochemistry and Western blotting revealed that p53 expression in spinal cord of high fluorosis group rats was increased compared with those in control group rats (422.69 ± 12.35 vs.177.82 ± 14.16;253.37 ± 10.42 vs.87.14 ± 7.39,t =77.212,72.988,all P ＜ 0.01).And p53 expression in spinal cord of defluorination group rats was increased compared with those in control group rats (418.75 ± 11.84 vs.163.47 ± 8.57;248.29 ± 10.23 vs.98.74 ± 11.52,t =95.663,53.167,all P＜ 0.01).But the differences were not statistically significant (418.75 ± 11.84 vs.422.69 ± 12.35;248.29 ± 10.23 vs.253.37 ± 10.42,t =1.261,1.906,all P ＞ 0.05).Conclusions There is apoptosis of neurocytes in the spinal cord of chronic fluorosis rats;overexpression of p53 probably plays an important role in the mechanism of damage induced by excessive fluorine.Apoptosis can not be recovered after defluorination for a short time,and persistent overexpression of p53 may be one of the reasons that apoptosis of neurocytes in the spinal cord can not decrease.

Objective To compare the prophylactic effect of laminar closure between titanium miniplate and anchor fixation in open-door cervical laminoplasty.Methods Between January 2010 and December 2010,63 patients with cervical spondylotic myelopathy were treated by open-door laminoplasty.Of them,30 patients underwent laminoplasty by titanium miniplate fixation and 33 by anchor fixation.During follow-up,multi-detector CT was performed preoperatively,at 1 week and 6 months after surgery.At each level,the anteroposterior diameter (APD) of the spinal canal and opening angle (OA) were measured.And the spinal canal expansion rate are calculated.MRI was performed preoperatively and 1 year after surgery to evaluate the severity of cord compression.Results All incisions healed by first intention.The incidence of postoperative axial symptoms in miniplate fixation group and anchor fixation group were 33.3％ (10/30) and 39.4％ (13/33),respectively.The OA,APD,and the spinal canal expansion rate of patients in both groups improved significant postoperatively,but differing from miniplate fixation group.The OA,the APD and the spinal canal expansion rate in anchor fixation group after 6 months were reduced than one week after surgery,and the difference between the groups was statistically significant.Lamina close in two groups was not found.CT images at 6 months showed complete fusion of the hinge area by mature bone or callus in two groups,by cervical sagittal MRI assessment.The severity of spinal cord compression was improved after 1 year.Preoperative and 1 year after the surgery,the severity of spinal cord compression between the two groups showed no significant difference.The severity of spinal cord compression after 1 year in both groups were no more than three grade.Conclusion Open-door cervical laminoplasty by anchor fixation or titanium miniplate can effectively prevent the occurrence of postoperative lamina closure,which can help patients to do functional exercises early,but improvement of spinal cord compression has no significant difference between both of them.However,titanium miniplate fixation for maintenance of the expansive spinal canal is better.

Objective To evaluate and compare C5 palsy and closure of the opened lamina after expansive open-door Laminoplasty (EOLP) with miniplate or suture/anchor fixation.Methods Between January 2011 and January 2013,a total of 142 patients with cervical myelopathy who were treated by EOLP were divided into hinge-side fixation group (fixed with suture/anchor,78 cases)and open-side fixation group (fixed with miniplate,64 cases).The Japanese Orthopaedic Association (JOA) score was used for neurological assessment and recovery rate (RR) counting.Opening angles,cervical curvature index (CCI),posterior shifting of spinal cord (PSSC) and severity of cord compression were recorded and compared.Results All patients in both group were followed up for more than 12 months.All incisions healed by first intention.C5 palsy occurred in 9 patients (9/78,11.5％) of hingeside fixation group,and 1 patients (1/64,1.6％) of open-side fixation group,showing significant difference (P=0.047).Opening angles and PSSC in hinge-side fixation group were greater than that in open-side fixation group.PSSC of 10 patients with C5 palsy were 3.97±1.19 mm,and greater than that of other patients without C5 palsy 2.57± 1.01 mm.There was no significant difference in CCI before (12.23％±3.70％,11.38％±4.29％) and 1 week (12.12％±3.77％,11.31％±4.35％) after operation.No significant difference was found in JOA scores (12.35±1.09,13.55±0.91),JOA improvement rate (64.24％±9.49％,61.78％±11.48％) and cord compression (0.74±0.71,0.75±0.67) at 12 months after operation.In 6 months postoperatively,27％ of patients in hinge-side fixation group,none in open-side fixation group were identified with 10％ decrease or more in opening angles of lamina.Conclusion EOLP with miniplate fixation has the same clinical outcome as fixed with suture/anchor,but will reduce the incidence of C5 palsy and prevent further closure of the opened lamina.

BACKGROUND:With the increase of the incidence of cervical spondylosis,it is particularly important to control the postoperative bleeding and related inflammatory reaction of cervical vertebra. OBJECTIVE:A prospective study was conducted to investigate the combined effect of intravenous and topical tranexamic acid of different concentrations on postoperative blood loss and inflammatory response during posterior cervical decompressive laminectomy combined with lateral mass screw internal fixation and bone graft fusion. METHODS:From January 2020 to December 2022,150 patients who were scheduled to undergo posterior cervical decompressive laminectomy combined with lateral mass screw internal fixation and bone graft fusion for cervical spondylotic myelopathy in Tianjin People's Hospital were enrolled in the study.Patients were divided into A,B,and C groups(n=50)by randomized double-blind lottery.The patients in the A,B,and C groups were treated with 1%,3%,and 5%intravenous and topical tranexamic acid solution,respectively.Postoperative blood loss and inflammation-related indicators were compared among three groups.The occurrence of venous thromboembolism and hematoma was observed after operation. RESULTS AND CONCLUSION:(1)There were significant differences in blood loss-related indexes,such as intraoperative blood loss,overall blood loss,and occult blood loss among the three groups(P<0.01).The above indexes were significantly lower in groups B and C than that in group A.There was no significant difference between groups B and C(P>0.05).(2)On days 1 and 3 after surgery,the levels of inflammatory indicators including serum C-reactive protein and interleukin-6 were increased to varying degrees in the three groups compared to before surgery(P<0.05).As the drug concentration increased,its expression decreased,and there was a significant difference among the three groups(P<0.001).(3)Two cases of intramuscular venous thrombosis appeared in each of the three groups after surgery.No hematoma or pulmonary embolism occurred in all three groups.(4)It is concluded that in posterior cervical decompressive laminectomy combined with lateral mass screw internal fixation and bone graft fusion,intravenous combined with topical application of different concentrations of tranexamic acid is effective in reducing perioperative blood loss and inflammatory response.3%tranexamic acid achieves the same effect without significantly increasing the risk of postoperative venous thromboembolism.