Objective To evaluate the mid‐term efficacy of microendoscopic discectomy (MED) and microsurgical lumbar discectomy (MSLD) for treating lumbar disc herniation (LDH) .Methods 98 patients with single segment LDH in the Orthopedic department of the Second Hospital of Lanzhou University from March 2009 to April 2010 were divided into 2 groups ,including 44 cases undergoing MED and 54 cases undergoing MSLD .The operative efficacies were assessed by the visual analogue scale (VAS) , Japanese Orthopedic Association (JOA) scores and Oswestry Disability Index (ODI) .Results There were statistically significant differences in the skin incision length ,amount of intraoperative blood loss and time of returning to work between the two groups (P<0 .01) ,while the operation time ,average hospital stay time and incidence of complications showed no statistically significant differences (P>0 .05) .The mean follow‐up duration was 49 .13 months in the MED group and 47 .24 months in the MSLD group respectively .At the last follow‐up the postoperative back and leg pain VAS scores ,JOA scores and ODI in each group were signifi‐cantly improved compared with the preoperative data (P<0 .01) .However ,there were no statistically significant differences in the intergroup comparison .Conclusion MED and MSLD are the effective methods for treating single segment LDH .However ,MED has less trauma and early out‐of‐bed ambulation ,is an ideal minimally invasive surgery .

Objective To analyze of related factors in affecting condylar buttress plate (CBP) surgical treatment of distal femoral fractures.Methods One hundred patients with distal femoral fractures were grouped according to eight related factors (gender,age,fracture type,fracture classification,surgical time,reset quality,whether bone graft and plaster braking),respectively.Operative efficacy was scored by the Neer knee functional score table,and score ≥ 72 was excellent,while ＜ 72 was good.Eight related factors were carried out single factor analysis with x2 test to compare the operative efficacy of each group,then the related factors with single factor analysis result of P＜0.05 were put in Logistic multifactor regression analysis,in order to clarify the independent risk factors for CBP treatment of distal femoral fractures.Results There was no significant difference (P＞0.05) in the operative efficacy between male and female group,open fracture and closed fracture group.The difference between youth,middle-aged and elderly group,type A and type C fracture group was statistically significant (P＜0.05).The operative efficacy of patients got surgery within 7 d was obviously better than those who got surgery 7 d later (P＜0.05).The operative efficacy of patients who had no intraoperative bone graft was better than those who had bone graft (P＜0.05).The operative efficacy of satisfactory reset group and none plaster braking group was better than that of unsatisfied reset group and plaster braking group (P＜0.05),respectively.Conclusions Age,fracture type and reset quality are CBP therapy independent risk factors for the efficacy of operation for patients with distal femoral fractures,which will provide some reference for improving the operative efficacy of CBP operation in treatment of distal femoral fractures.

Objective To investigate the clinical efficacy of microendoscopic discectomy(MED) and fanestration discectomy (FD) for treating single segement lumbar disc herniation(LDH).Methods A total of 168 patients with single segment LDH were included in this retrospective study from April 2009 to Janurary 2012.The patients were divided into MED group(81 cases) and FD group(87 cases) according to surgery mode.The operation and hospitalization indexes for each group were collected and compared respectively.The clinical outcomes were evaluated by the visual analogue scale(VAS),Japanese Orthopedic Association(JOA) scores and Oswestry Disability Index(ODD.Lumbar curves(Cobb's angle),intervertebral space height,horizontal displacement and angular displacement before and after surgery were applied to evaluate the lumbar spinal stability.Results The skin incision length,amount of intraoperative blood loss,operation time and hospitalization duration in the MED group were less than that in the FD group(P＜0.05).All cases completed follow up for more than 4 years.The each item score at last follow up in the two groups was significantly improved compared with before operation(P＜0.05),the inter-group comparison had no statistical difference(P＞0.05).The postoperative lumbar curve and intervertebral space height were decreased in both groups.The postoperative lumbar curve in the FD group was decreased compared with the MED.One case in the MED group and 3 cases in the FD group appeared lumbar vertebral instability.Conclusion Both MED and FD for treating single segment LDH can gain better clinical effect,MED has short operation time,small trauma and little influence on lumbar vertebral stability,and is an effective minimal invasive surgery.

Objective To explore the effect of spinal sagittal balance on secondary vertebral fracture after percutaneous kyphoplasty (PKP) for osteoporotic vertebral compression fractures (OVCF).Methods The data were reviewed of the patients with single segmental OVCF who had undergone PKP at Department of Spine Surgery,Second Hospital of Lanzhou University from March 2014 to December 2015.Of them,21 had secondary vertebral fracture after PKP.As an observational group,they were matched with another 21 patients without secondary vertebral fracture after PKP as a control group (ratio:1:1) for age,gender,body mass index (BMI) and bone mineral density (BMD).Their standard standing plain radiographs of the whole spine were used to measure the parameters of spine-pelvis sagittal balance.The 2 groups were compared in sagittal balance parameters.Results The sagittal vertical axis (26.86 ± 33.55 mm) and thoracic kyphosis (47.62° ± 10.73°) in the observational group were significantly larger than those (4.05 ± 31.93 mm and 41.10 °±8.17°) in the control group (P ＜0.05);the lumbar lordosis (35.29°±8.77 °),sacral slope (22.71 ° ± 5.80°) and pelvic incidence (45.38° ± 7.49°) in the former were significantly smaller than those in the control group (41.71°±9.19°,27.43°±5.29° and 51.19°±8.44°) (P ＜0.05);there were no significant differences between the 2 groups in pelvic tilt or thoracolumbar kyphosis (P ＞ 0.05).Conclusions The OVCF patients with larger sagittal vertical axis,larger thoracic kyphosis and smaller lumbar lordosis may be more likely to suffer secondary vertebral fracture after PKP.A larger pelvic incidence may be a protective factor against secondary vertebral fracture after PKP for OVCF patients.

To investigate the effect of Parkinson's disease related protein DJ-1 on the cell proliferation, apoptosis, invasion and migration in human osteosarcoma cells and the underlying molecular mechanisms. 
 Methods: The protein expression levels of DJ-1 were detected in human osteosarcoma cell lines (MG-63, Saos-2, and U2OS) and human osteoblast cell line hFOB1.19 with or without deficiency in phosphatase and tensin homolog deleted from chromosome 10 (PTEN) were detected by Western blot. Osteosarcoma cells were treated with DJ-1 siRNA, and then the protein expression levels of DJ-1 were detected by Western blot. Cell survival rate of osteosarcoma cells was detected by cell counting kit-8 (CCK-8) assay. Cell apoptosis of osteosarcoma cells was measured by annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) double staining method. Cell invasive and migration ability of osteosarcoma cells were examined by transwell invasion and migration assay. 
 Results: Compared with that of human osteoblast cell line (hFOB1.19), the protein expression level of DJ-1 was significantly upregulated in human osteosarcoma cell lines (MG-63, Saos-2, and U2OS) (all P<0.05), and U2OS had the highest level of DJ-1 when compared with the other three cell lines (P<0.01). DJ-1 siRNA could significantly down-regulate the DJ-1 protein expression in U2OS cells, and also diminish the cell survival rate. Moreover, DJ-1 down-regulation of DJ-1 could promote cell apoptosis, suppress the ability of cell invasion and migration, and increase the PTEN protein expression level (all P<0.05). In addition, the protein expression level of PTEN was markedly up-regulated in human osteosarcoma cell lines when compared with that in the hFOB1.19 cells (P<0.05). 
 Conclusion: DJ-1 can promote the cell proliferation, inhibit cell apoptosis, and decrease the ability of cell invasion and migration, and the potential underlying mechanisms may be associated with the up-regulation of PTEN protein expression.
Apoptosis ; genetics ; Cell Line, Tumor ; Cell Movement ; genetics ; Cell Proliferation ; genetics ; Gene Expression Regulation, Neoplastic ; Humans ; Neoplasm Invasiveness ; genetics ; PTEN Phosphohydrolase ; genetics ; Parkinson Disease ; physiopathology ; Protein Deglycase DJ-1 ; genetics ; metabolism ; RNA, Small Interfering ; genetics

【Objective】 To study the clinical practice and early outcome of percutaneous full-endoscopic modified posterior lumbar interbody fusion（mPLIF）combined with pedicle screw fixation through paraspinal muscle clearance. 【Methods】 A retrospective study was conducted to analyze the clinical data of patients with lower lumbar spinal diseases treated from May 2019 to April 2020. All the enrolled patients received mPLIF combined with pedicle screw fixation through paraspinal muscle clearance. The follow-up period was more than 1 year； the general parameters included age， gender， duration of disease， diagnosis of disease， surgery segment， and postoperative hospitalization time. Operation parameters included operation time and blood loss. We obtained the clinical parameters such as visual analogue scale （VAS） score for back and lower extremity， Oswestry disability index （ODI） score， and Macnab satisfaction score at the last follow-up. We evaluated the imaging parameters including intervertebral disc height， segmental lordosis angle， lumbar lordosis angle， as well as fusion outcome of patients with single segmental lumbar disease. In addition， intraoperative and postoperative complications were recorded. 【Results】 Totally 18 patients met the inclusion criteria， among whom 8 were male and 10 were female， with the average age of （53.3±8.3） years old and the average duration of disease being （28.9±36.6） months. Among them 16 patients were diagnosed as lumbar degenerative disease and the other 2 had lumbar disc infection. One patient received L3-L4 and L4-L5 intervertebral fusion； the others had one-segmental fusion， among which 11 cases were L4-L5 and 6 cases were L5-S1. The average operation time was （207.8±31.7） min， and the average blood loss was （25.6±7.8） mL， and the mean postoperative hospitalization time was （6.56±2.30） days. VAS scores of back and lower extremities at postoperative 1 week， 6 months and the last follow-up were statistically significantly improved from the preoperative scores. ODI scores at postoperative 6 months and the last follow-up were also statistically significantly improved. The rate of excellent and good according to the Macnab criteria was 94.4%. For the 17 single-level fusion patients， intervertebral height was significantly higher postoperatively and at the last follow-up compared with that of the preoperative one （P<0.05）. Segmental lordosis angle was bigger postoperatively and at the last follow-up （P>0.05）， which was not statistically significant. Lumbar lordosis angle was significantly bigger postoperatively （P<0.05） and bigger at the last follow-up， but with no statistical significance （P>0.05）. The fusion rate at the last follow-up was 88.2%. The cage broke in the process of implantation in one patient. A cage retroposition occurred in one patient at the follow-up. 【Conclusion】 Percutaneous full-endoscopic modified posterior lumbar interbody fusion combined with pedicle screw fixation through bilateral paraspinal muscle clearance by one incision showed excellent clinical outcomes in treating many kinds of lower lumbar diseases. This operation should be an excellent option for lower lumbar fusion.