Rosuvastatin Enhances Lymphangiogenesis after Myocardial Infarction by Regulating the miRNAs/Vascular Endothelial Growth Factor Receptor 3 (miRNAs/VEGFR3) Pathway.

BACKGROUND: Several clinical studies have suggested that the early administration of statins could reduce the risk of in-hospital mortality in acute myocardial infarction (AMI) patients. Recently, some studies have identified that stimulating lymphangiogenesis after AMI could improve cardiac function by reducing myocardial edema and inflammation. This study aimed to identify the effect of rosuvastatin on postinfarct lymphangiogenesis and to identify the underlying mechanism of this effect. METHOD: Myocardial infarction (MI) was induced by ligation of the left anterior descending coronary artery in mice orally administered rosuvastatin for 7 days. The changes in cardiac function, pathology, and lymphangiogenesis following MI were measured by echocardiography and immunostaining. EdU, Matrigel tube formation, and scratch wound assays were used to evaluate the effect of rosuvastatin on the proliferation, tube formation, and migration of the lymphatic endothelial cell line SVEC4-10. The expression of miR-107-3p, miR-491-5p, and VEGFR3 was measured by polymerase chain reaction (PCR) and Western blotting. A gain-of-function study was performed using miR-107-3p and miR-491-5p mimics. RESULTS: The rosuvastatin-treated mice had a significantly improved ejection fraction and increased lymphatic plexus density 7 days after MI. Rosuvastatin also reduced myocardial edema and inflammatory response after MI. We used a VEGFR3 inhibitor to partially reverse these effects. Rosuvastatin promoted the proliferation, migration, and tube formation of SVEC4-10 cells. PCR and Western blot analyses revealed that rosuvastatin intervention downregulated miR-107-3p and miR-491-5p and promoted VEGFR3 expression. The gain-of-function study showed that miR-107-3p and miR-491-5p could inhibit the proliferation, migration, and tube formation of SVEC4-10 cells. CONCLUSION: Rosuvastatin could improve heart function by promoting lymphangiogenesis after MI by regulating the miRNAs/VEGFR3 pathway.

An esterase-responsive ibuprofen nano-micelle pre-modified embryo derived nucleus pulposus progenitor cells promote the regeneration of intervertebral disc degeneration.

Stem cell-based transplantation is a promising therapeutic approach for intervertebral disc degeneration (IDD). Current limitations of stem cells include with their insufficient cell source, poor proliferation capacity, low nucleus pulposus (NP)-specific differentiation potential, and inability to avoid pyroptosis caused by the acidic IDD microenvironment after transplantation. To address these challenges, embryo-derived long-term expandable nucleus pulposus progenitor cells (NPPCs) and esterase-responsive ibuprofen nano-micelles (PEG-PIB) were prepared for synergistic transplantation. In this study, we propose a biomaterial pre-modification cell strategy; the PEG-PIB were endocytosed to pre-modify the NPPCs with adaptability in harsh IDD microenvironment through inhibiting pyroptosis. The results indicated that the PEG-PIB pre-modified NPPCs exhibited inhibition of pyroptosis in vitro; their further synergistic transplantation yielded effective functional recovery, histological regeneration, and inhibition of pyroptosis during IDD regeneration. Herein, we offer a novel biomaterial pre-modification cell strategy for synergistic transplantation with promising therapeutic effects in IDD regeneration.

Cervical rotational osteotomy for correction of axial deformity in a patient with ankylosing spondylitis.

PURPOSE: Severe cervical axial deformity associated with ankylosing spondylitis (AS) is rare in clinic, and there are little concerns about surgical treatment of axial deformity associated with AS. The case study aims to show the surgical technique to perform cervical rotational osteotomy. METHODS: We present the case of a young AS patient whose neck was fixed in a left-rotational posture at 18°, requiring his trunk to be turned to the right to look forward visually. This made his gait appear to be limping, inconveniencing him with great difficulty. In order to correct this deformity, we performed a novel cervical rotational osteotomy through a one-stage posterior-anterior-posterior approach. Firstly, we performed laminectomies of C7 and T1, followed by a C7/T1 facetectomy with release of the bilateral C8 nerve roots. Next, we performed C7/T1 discectomy, bony resection of the lateral body and uncovertebral joints. The head of the patient was then rotated manually, so that both his face and torso were simultaneously facing frontward. Finally, rods spanning the screws from C6 to T2 were fixed. RESULTS: Postoperatively, the patient's axial malalignment was significantly improved, and he was able to walk normally. Surgical outcomes were well maintained at a 3-year follow-up. CONCLUSION: Through this case, we hope to draw the attention to spinal axial deformity and provide a reference point in the surgical treatment of spinal axial deformity.

Predictors for second-stage posterior direct decompression after lateral lumbar interbody fusion: a review of five hundred fifty-seven patients in the past five years.

PURPOSE: To analyze the predictors for second-stage posterior direct decompression (PDD) after lateral lumbar interbody fusion (LLIF) procedure. METHODS: We studied patients who underwent LLIF for degenerative lumbar spinal stenosis in the last five years, from July 2016 to June 2021. All surgical levels were grouped according to Schizas' central canal stenosis (CCS) classification, Pathria's facet joint degeneration (FJD) classification, Bartynski's lateral recess stenosis (LRS) classification, and Lee's foraminal stenosis (FS) classification. Second-stage PDD rates of each subgroup and their annual change were analyzed. Evaluation of risk factors associated with PDD was investigated. RESULTS: A total of 901 segments from 557 patients were included. The overall PDD rate was 29.97%. An overall PDD rate of 75.21% for grade D CCS, 29.74% for grade C CCS, 41.67% for grade 3 FJD, 37.61% for grade 3 LRS, and 40.70% for grade 3 FS was shown. While there was a continuous decline in annual PDD rate in the past four years, the annual PDD rate for grade D remained at very high levels. Logistic regression analysis had shown grade D CCS as the utmost risk factor for PDD (OR = 17.77). And grade 3 LRS (OR = 4.63), grade 3 FS (OR = 2.42), grade C CCS (OR = 2.41), and grade 3 FJD (OR = 2.04) were also moderately correlated with PDD, which meant they only moderately increased the risk of PDD. CONCLUSION: Extreme severe lumbar CCS (grade D) is the greatest determinant to perform the second-stage PDD procedure after LLIF.

Anterior Selective Lumbar Fusion Saving More Distal Fusion Segments Compared with Posterior Approach in the Treatment of Adolescent Idiopathic Scoliosis with Lenke Type 5: A Cohort Study with More Than 8-Year Follow-up.

OBJECTIVE: To investigate whether anterior selective fusion (ASF) could save more distal fusion segments compared with posterior approach in the treatment of Lenke type 5 adolescent idiopathic scoliosis with long term follow-up. METHODS: A retrospective cohort study. From 2008 to 2011, 22 AIS girls with Lenke type 5 who underwent ASF or posterior selective fusion (PSF) with more than 8-year follow-up, were extracted from the database. 13 girls in the ASF group had an average age of 14.3 ± 1.3 years and Risser sign of 3.3 ± 1.1; 9 PSF girls had an average age of 16.2 ± 3.6 years and Risser sign of 3.8 ± 1.5. The radiographic outcome was compared between groups preoperatively, 6-month postoperatively, 8-year postoperatively and at last follow-up (>8 years). RESULTS: The average follow-up duration was 8.7 ± 0.4 (ASF) and 8.8 ± 0.5 (PSF) years, respectively. There was no significant difference at baseline in age, Risser sign and preoperative curve pattern in the coronal and sagittal plane between the groups (P > 0.05). The ASF group had significantly shorter fusion segments (5.1 ± 0.6 vs. 7.0 ± 1.3) and decreased upper instrumented vertebra (UIV) (T11 ± 0.8 vs. T10 ± 0.8) than the PSF (P < 0.05); while no significant difference was found in the lower instrumented vertebra (LIV) and distal reserved segments (P > 0.05), which suggested that ASF could shorten the fusion segments by lowering UIV. The distal compensatory curve in the ASF group (9.0° ± 3.9°) was significantly larger than in the PSF group (3.3° ± 2.4°, P = 0.003), despite of no significant difference in the incidence of coronal imbalance (P > 0.05), indicating that both two approaches could obtain satisfactory correction in the coronal plane. In the sagittal plane, PSF patients had significantly larger lumbar lordosis (LL, 59.1° ± 10.5°), thoracic kyphosis (TK, 37.2° ± 13.3°) and proximal junctional angle (PJA, 13.3° ± 6.1°) at the last follow-up than the ASF (LL: 43.4° ± 9.4°; TK: 20.7° ± 8.4°; PJA: 4.7° ± 3.4°; P < 0.05), but without significant difference in proximal junctional kyphosis (PJK) and sagittal vertical axis (SVA) (P > 0.05). After controlling for age, Risser sign, and radiographic parameters related to the primary curve pattern, shorter fusion segments and more distal reserved segments still remained significant in the ASF group with greater Risser sign (P < 0.05). No major intra- or post-operative complications occurred. CONCLUSIONS: Both ASF and PSF could obtain satisfactory coronal and sagittal correction for Lenke 5 AIS; compared with PSF, ASF could shorten the fusion segments by lowering UIV, and save more distal fusion segments only in patients with greater skeletal maturity.

Cervical Flexion Osteotomy through One-Stage Posterior-Anterior-Posterior Approach for Cervical Extension Deformity in Ankylosing Spondylitis: A Novel Surgical Technique.

The present study was to introduce a new surgical technique of cervical flexionosteotomy, with an emphasis on the clinical and radiographic outcomes. Two male patients aged 45 and 21 years presented with cervical extension deformity in ankylosing spondylitis (AS). Both patients exhibited upward deviation of the forward gaze. The chin brow vertical angle (CBVA) were 15° upward and 5° downward, respectively; and the sagittal vertical axis (SVA) were-13.2mm and 195.7mm, respectively. Aposterior transverse release was performed at C7 -T1 , exposing the theca and C8 nerve roots to facilitate closure of theosteotomy site. Then, an anterior closing-wedgeosteotomy of C7 -T1 was performed followed with anterior internal fixation with a locking plate to prevent any translation. After closure and anterior fixation, patients were returned to the proneposition, and posterior screw-rod instrumentation was used for further stabilization. The follow-up periods were 20 and 10 months, respectively. At the last follow-up, CBVA and SVA of Patient 1 were 14° downwardand -12.6mm; and CBVA and SVA of Patient 2 were 1° downward and 75.6mm respectively, indicating the visual angle and sagittal balance were significantly improved. No intraoperative or postoperative complications were encountered. Full-spine radiographs of each patient at the last visit confirmed successfulbony union. The present study was the first report introducing a novel flexion osteotomy for cervical extension deformity in AS through a posterior-anterior-posterior approach inone-stage. The improved forward gaze and no complications demonstrated the effectiveness and safety of the novel technique, suggesting that it might provide a more feasible method for the correction of cervical extension deformity.

Radiographic and clinical outcome of lateral lumbar interbody fusion for extreme lumbar spinal stenosis of Schizas grade D: a retrospective study.

BACKGROUND: Extreme lumbar spinal stenosis was thought to be a relative contraindication for lateral lumbar interbody fusion (LLIF) and was excluded in most studies. This is a retrospective study to analyze the radiographic and clinical outcome of LLIF for extreme lumbar spinal stenosis of Schizas grade D. METHODS: For radiographic analysis, we included 181 segments from 110 patients who underwent LLIF between June 2017 and December 2018. Lumbar spinal stenosis was graded according to Schizas' classification. Anterior and posterior disc heights, disc angle, foramen height, spinal canal diameter and central canal area were measured on CT and MRI. For clinical analysis, 18 patients with at least one segment of grade D were included. Visual analogue scale (VAS) and Oswestry disability index (ODI) scores were used to evaluate clinical outcome. Continuous variables were compared using Student's t-test, with P-values < 0.05 considered to indicate statistically significant differences. RESULTS: Among the 181 segments included for radiological evaluation, there were 23 grade A segments, 37 grade B segments, 103 grade C segments and 18 grade D segments. Postoperatively, the average change of midsagittal canal diameter of grade D was significantly greater than that of grade A, and not significantly different compared to grades B and C. As to the average change of disc height, bilateral foraminal height, disc angle and central canal area (CCA), grade D was not significantly different from the others. The average postoperative CCA of grade D was significantly smaller than the average preoperative CCA of grade C. Eighteen patients with grade D stenosis were followed up for an average of 19.61 ± 6.32 months. Clinical evaluation revealed an average improvement in the ODI and VAS scores for back and leg pain by 20.77%, 3.67 and 4.15 points, respectively. Sixteen of 18 segments with grade D underwent posterior decompression. CONCLUSION: The radiographic decompression effect of LLIF for Schizas grade D segments was comparable with that of other grades. Posterior decompression was necessary for LLIF to achieve a satisfactory clinical outcome for extreme lumbar spinal stenosis of Schizas grade D.

The biomechanical study of a modified lumbar interbody fusion-crenel lateral interbody fusion (CLIF): a three-dimensional finite-element analysis.

To analyze the biomechanical stability of a redesigned cage, a new lateral plate and the effect of length of cage in CLIF, an L4-L5 finite element model was performed. Six different internal fixation methods were designed and operated under six conditions (Stand-alone CLIF; CLIF with unilateral pedicle screws (CLIF + UPS); CLIF with bilateral pedicle screws (CLIF + BPS); CLIF with lateral plate (CLIF + LP); CLIF with lateral plate and unilateral pedicle screws (CLIF + LP + UPS); CLIF with lateral plate and bilateral pedicle screws (CLIF + LP + BPS)). Ranges of motion (ROM) and stress distribution were evaluated. The effect of the length of cage was analyzed. The ROMs of stand-alone CLIF group and other internal fixation groups were decreased by >90% compared with the intact group. The CLIF + LP + BPS group has the minimum ROM. The CLIF + LP group has smaller ROM than stand-alone group. The stand-alone group has the minimum stress except for extension condition. The CLIF + LP model has less ROM, but a greater stress load was observed in the lateral plate. As for the length of cage, the largest stress is located at the junction between cage and distal end plate, especially in the epiphyseal ring and cortical compact. We conduct a new 'cylinder wall theory' that the cage should be placed to cover the epiphyseal ring. We recommend the length of cage should cover the epiphyseal ring to reduce the subsidence of cage.

Enhanced recovery care versus traditional care following laminoplasty: A retrospective case-cohort study.

Enhanced recovery after surgery (ERAS) has been shown to shorten length of hospital stay and reduce perioperative complications in many types of surgeries. However, there has been a paucity of research examining the application of ERAS to major spinal surgery. The current study was performed to compare complications and hospital stay after laminoplasty between an ERAS group and a traditional care group.The ERAS group included 114 patients who underwent laminoplasty managed with an ERAS protocol between January 2016 and June 2017. The traditional care group included 110 patients, who received traditional perioperative care between November 2014 and December 2015. Postoperative hospital stay (POPH), physiological function, postoperative visual analogue scale (VAS) pain score, and postoperative complications were compared between the 2 groups.The mean POPH was significantly shorter in the ERAS group than traditional care group (5.75 ±â€Š2.46 vs. 7.67 ±â€Š3.45 d, P < .001). ERAS protocol significantly promoted postoperative early food-taking (8.45 ±â€Š2.94 h vs 21.64 ±â€Š2.66 h, P < .001), reduced the first time of assisted walking (30.79 ±â€Š14.45 vs. 65.24 ±â€Š25.34 h, P < .001), postoperative time of indwelling urinary catheters (24.76 ±â€Š12.34 vs. 53.61 ±â€Š18.16 h, P < .001), and wound drainage catheters (43.92 ±â€Š7.14 vs. 48.85 ±â€Š10.10 h, P < .001), as compared with the traditional care group. Pain control was better in the ERAS group than traditional care group in terms of mean VAS score (2.72 ±â€Š0.46 vs. 3.35 ±â€Š0.46, P < .001) and mean maximum VAS score (3.76 ±â€Š1.12 vs. 4.35 ±â€Š1.15, P < .001) in 3 days after surgery. The morbidity rate was 21.05% (24 of 114 patients) in the ERAS group and 20.90% (23 of 110 patients) in the control group (P = .75).The ERAS protocol is both safe and feasible for patients undergoing laminoplasty, and can decrease the length of postoperative hospitalization without increasing the risk of complications.

Clinical Features and Prognostic Factors in Elderly Ewing Sarcoma Patients.

BACKGROUND Elderly patients with Ewing sarcoma have a very poor prognosis, and treatment remains a challenge. However, the outcomes and potential prognostic factors of elderly Ewing sarcoma patients are rarely documented. Therefore, we investigated the prognosis of this special cohort and determine independent prognostic factors. MATERIAL AND METHODS A cohort of Ewing sarcoma patients aged over 40 years from 1973 to 2015 was identified from the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) database. The Kaplan-Meier method and a Cox proportional hazard regression model were used for the prognostic analysis. RESULTS A total of 162 patients were included with a mean age of 53 years. The 5-year overall survival (OS) and cancer-specific survival (CSS) rates of the entire group were 43.7% and 47.9%, respectively. The sex, location, tumor size, and radiation treatment had no effect on survival outcomes on univariate analysis. Tumor stage, surgery, and chemotherapy were significant indicators of both OS and CSS on multivariable analysis. CONCLUSIONS Surgery in combination with chemotherapy had a significant survival benefit in elderly Ewing sarcoma patients and should be recommended.

Biomechanical evaluation of tendon connection with novel suture techniques.

PURPOSE: Achilles tendon rupture is a severe injury with poor curative effect due to its anatomical characteristic and mechanical peculiarity. Internal fixation of limited loop (IFLL) with steel-wire has been applied on patients with tendon rupture to fix the broken ends before physical rehabilitation. The purpose of this study is to investigate the biomechanical property and radiological characteristic of such suture technique for the repairment of tendon rupture. METHODS: Tendons of pigs' hint feet were separated for the biomechanical study. Suture surgery was performed according to the protocol of IFLL. Biomechanical Testing Machine was adopted to conduct the biomechanical tensile load examination. The maximal load, elastic modulus and tendon stiffness of the stitched tendons with or without reinforcement were examined. RESULTS: The maximum tensile load of the stitched tendons using IFLL reached 1/4 of the uninjured tendon's maximum tensile load, indicating that such suture technique is capable of providing enough tension for the ruptured tendon. Surprisingly, tendons fixed with titanium wire showed the highest load tension, which was comparable to the undamaged tendon. Therefore, we found the biomechanical basis of using IFLL in effectively connecting the rupture ends of tendons. CONCLUSIONS: In conclusion, we provide biomechanical evidence for the use of IFLL in treatment of Achilles tendon rupture, by providing enough strength for the ankle function. Such suture technique could help the patients with better rehabilitation and reduced in-hospital stay after Achilles tendon injury.

Computer Simulation of Two-level Pedicle Subtraction Osteotomy for Severe Thoracolumbar Kyphosis in Ankylosing Spondylitis.

BACKGROUND: Advanced ankylosing spondylitis is often associated with thoracolumbar kyphosis, resulting in an abnormal spinopelvic balance and pelvic morphology. Different osteotomy techniques have been used to correct AS deformities, unfortunnaly, not all AS patients can gain spinal sagittal balance and good horizontal vision after osteotomy. MATERIALS AND METHODS: Fourteen consecutive AS patients with severe thoracolumbar kyphosis who were treated with two-level PSO were studied retrospectively. All were male with a mean age of 34.9 ± 9.6 years. The followup ranged from 1-5 years. Preoperative computer simulations using the Surgimap Spinal software were performed for all patients, and the osteotomy level and angle determined from the computer simulation were used surgically. Spinal sagittal parameters were measured preoperatively, after the computer simulation, and postoperatively and included thoracic kyphosis (TK), lumbar lordosis (LL), sagittal vertical axis (SVA), pelvic incidence, pelvic tilt (PT), and sacral slope (SS). The level of correlation between the computer simulation and postoperative parameters was evaluated, and the differences between preoperative and postoperative parameters were compared. The visual analog scale (VAS) for back pain and clinical outcome was also assessed. RESULTS: Six cases underwent PSO at L1 and L3, five cases at L2 and T12, and three cases at L3 and T12. TK was corrected from 57.8 ± 15.2° preoperatively to 45.3 ± 7.7° postoperatively (P < 0.05), LL from 9.3 ± 17.5° to -52.3 ± 3.9° (P < 0.001), SVA from 154.5 ± 36.7 to 37.8 ± 8.4 mm (P < 0.001), PT from 43.3 ± 6.1° to 18.0 ± 0.9° (P < 0.001), and SS from 0.8 ± 7.0° to 26.5 ± 10.6° (P < 0.001). The LL, VAS, and PT of the simulated two-level PSO were highly consistent with, or almost the same as, the postoperative parameters. The correlations between the computer simulations and postoperative parameters were significant. The VAS decreased significantly from 6.1 ± 1.9 to 2.0 ± 1.1 (P < 0.001). In terms of clinical outcome, 10 cases were graded "excellent" and 4 cases were graded "good." CONCLUSION: Two-level PSO using a preoperative computer simulation is a feasible, safe, and effective technique for the treatment of severe thoracolumbar kyphosis in AS patients with normal cervical motion.

Clinical outcome of laminoplasty for cervical ossification of the posterior longitudinal ligament with K-line (-) in the neck neutral position but K-line (+) in the neck extension position: A retrospective observational study.

Patients with cervical ossification of the posterior longitudinal ligament (OPLL) who are K-line (-) are thought to have poor clinical outcomes after laminoplasty. The aim of this study is to compare the clinical results of patients with OPLL who were K-line (-) in the neck neutral position but K-line (+) in the neck extension position (NEP group) with patients with OPLL who were K-line (+) in the neck neutral position (NNP group).Retrospectively, 42 patients who underwent cervical laminoplasty for OPLL by our surgical group during 2012 and 2013 were reviewed and were followed for at least 2 years. The patients were divided into 2 groups according to K-line status. Standing plain radiographs of the cervical spine were obtained pre- and postoperatively. Cervical spine alignment parameters included the C2-7 Cobb angle and range of motion (ROM) measured on lateral radiographs. Clinical evaluation included pre- and postoperative JOA, NDI, and VAS scores.Ten patients were classified in the NEP group, and 32 patients were classified in the NNP group. Preoperatively, the OPLL involved segments were 4.10 ±â€Š1.66 in the NEP group and 2.53 ±â€Š1.16 in the NNP group (P = .005). The canal-occupying ratios were 58.40 ±â€Š11.11% in the NEP group and 29.08 ±â€Š11.38% in the NNP group (P < .001). The mean Cobb angle of both the groups had not changed significantly at the last follow-up. The mean cervical ROM of both the groups had decreased at the last follow-up. The mean JOA score of the NEP group improved significantly from 9.70 ±â€Š2.16 to 12.50 ±â€Š2.27 (P = .014). The mean JOA score of the NNP group improved significantly from 11.91 ±â€Š1.69 to 14.93 ±â€Š1.58 (P < .001). The mean JOA recovery rate was 32.71 ±â€Š40.45% in the NEP group and 59.00 ±â€Š33.80% in the NNP group (P = .036). The NDI scores of both groups were significantly decreased, and the VAS scores of both groups had not changed significantly at the last follow-up.Laminoplasty is a relatively effective and safe procedure for patients with K-line (-) in the neck neutral position but K-line (+) in the neck extension position. Instead of anterior surgery, we recommend laminoplasty for those patients with OPLL extending to 3 or more segments.

[Comparative study of minimally invasive percutaneous pedicle screw fixation and open surgery in the treatment of thoracolumbar fractures].

OBJECTIVE: To compare the clinical outcomes of minimally invasive percutaneous pedicle screw fixation and open surgery in the treatment of thoracolumbar fracture. METHODS: A retrospective study of patients who had undergone surgery for thoracolumbar fracture from June 2014 to December 2014 was performed. Sixty-one cases were included and 29 cases were treated by minimally invasive percutaneous pedicle screw fixation (minimally invasive group) and 32 cases were treated by the traditional open pedicle screw fixation(open group). The differences in the total length of the incision, intraoperative fluoroscopy times, operative time, blood loss, the preoperative and postoperative visual analogue scale(VAS), postoperative bedridden time and hospital stay were compared. And the preoperative and postoperative anterior vertebral body height and Cobb angle of the kyphosis were also compared. RESULTS: Compared with the open group, the total length of incision was smaller and intraoperative blood loss was less, bedridden time and hospital stay were shorter, and pain of the wound was less in the minimally invasive group. Postoperatively, the anterior vertebral body height was retorted and the Cobb angle of the kyphosis was corrected obviously in both groups. But no significant difference in the imaging results was found between two groups(P>0.05). CONCLUSIONS: Minimally invasive percutaneous pedicle screw fixation has the similar fixation efficacy with open surgery in treating thoracolumbar fracture. However, it can avoid extensive muscle stripping, and obviously reduce the surgical incision, operative time, postoperative pain, bedridden time and hospital stay. According to the clinical efficacy, it is worthy of clinical application.

The potential of chondrogenic pre-differentiation of adipose-derived mesenchymal stem cells for regeneration in harsh nucleus pulposus microenvironment.

Recent studies indicated that cell-based therapy could be a promising approach to treat intervertebral disc degeneration. Though the harsh microenvironment in disc is still challenging to implanted cells, it could be overcome by pre-conditioning graft cells before transplantation, suggested by previous literatures. Therefore, we designed this study to identify the potential effect of chondrogenic pre-differentiation on adipose-derived mesenchymal stem cells in intervertebral disc-like microenvironment, characterized by limited nutrition, acidic, and high osmosis in vitro. Adipose-derived mesenchymal stem cells of rat were divided into five groups, embedded in type II collagen scaffold, and cultured in chondrogenic differentiation medium for 0, 3, 7, 10, and 14 days. Then, the adipose-derived mesenchymal stem cells were implanted and cultured in intervertebral disc-like condition. The proliferation and differentiation of adipose-derived mesenchymal stem cells were evaluated by cell counting kit-8 test, real-time quantitative polymerase chain reaction, and Western blotting and immunofluorescence analysis. Analyzed by the first week in intervertebral disc-like condition, the results showed relatively greater proliferative capability and extracellular matrix synthesis ability of the adipose-derived mesenchymal stem cells pre-differentiated for 7 and 10 days than the control. We concluded that pre-differentiation of rat adipose-derived mesenchymal stem cells in chondrogenic culture medium for 7 to 10 days could promote the regeneration effect of adipose-derived mesenchymal stem cells in intervertebral disc-like condition, and the pre-differentiated cells could be a promising cell source for disc regeneration medicine.

[Multivariate analysis for prognostic factors on non-operative treatment of cervical spinal cord injury without fracture or dislocation].

OBJECTIVE: To analyze the factors in the non-operative treatment of cervical spinal cord injury without fracture or dislocation. METHODS: The clinical data of 122 patients with cervical spinal cord injury without fracture or dislocation from January 2009 to December 2012 treated by non-operative treatment were retrospectively reviewed. There were 84 males and 38 females, aged from 18 to 83 years with an average of (52.37 +/- 13.27) years. The clinical features, such as age, gender, cause of injury, time from injury to treatment, ASIA grade of spine cord injury, MRI type of spine cord injury, range of spine cord injury, effective cervical spinal canal ratio, Pfirrmann grade of intervertebral disc herniation, segment of intervertebral disc herniation, intervertebral disc ligament complex injury, treatment of high-dose methyiprednisolone, were observed. Single factor and multiple factor Logistic regression analysis were used in the clinical data in order to analyze the influencing factors of above items to prognosis. RESULTS: For univariate analysis, the factors such as MRI type of spine cord injury, extent of spine cord injury, effective cervical spinal canal ratio, Pfirrmann grade of intervertebral disc herniation, segment of intervertebral disc herniation, ASIA grade of spine cord injury, associated with prognosis (P < 0.05). Multiple linear regression analysis showed that the main prognostic factors including MRI type of spine cord injury, range of spine cord injury, effective cervical spinal canal ratio, Pfirrmann grade of intervertebral disc herniation, ASIA grade of spine cord injury according to its effective intension (P < 0.05). CONCLUSION: The main prognostic factors on non-operative treatment of cervical spinal cord injury without fracture or dislocation were MRI type and extent of spine cord injury, meanwhile, correlate with effective cervical spinal canal ratio, Pfirrmann grade of intervertebral disc herniation, ASIA grade of spine cord injury. It is deliberative to choose no-operative treatment, for it only refers to the patients with the mild localized edema type or no signal change of spinal cord in MRII. Operative treatment shoud be recommended for other patients.

[Anterior slip phenomenon of the vertebrae after corpectomy surgery and its clinical significance].

OBJECTIVE: To investigate the anterior slip phenomenon of the vertebrae after corpectomy surgery and its clinical significance. METHODS: The clinical data of 164 patients with cervical spondylotic myelopathy treated from January 2010 to April 2013 were retrospectively analyzed. There were 88 males and 76 females, aged from 38 to 74 years old with the mean of 56.2 years. Among them, 31 cases for C4 corpectomy, 87 cases for C5 corpectomy, 46 cases for C6 corpectomy. Preoperative and postoperative distance of posterior wall of vertebral canal to the line of adjacent upper vertebral bodies anterosuperior border and lower vertebral bodies anteroinferior border was measured by CT in cervical sagittal middle layer scanning as the center, anterior slip degree of the vertebrae after operation was evaluated. The fast clustering method was used, the vertebral shift distance as variable, according to the size of the forward distance, 90 cases classified as group 1(forward greatly group), and the 74 cases classified as group 2(forwad short group). The relationships on the anterior slip of the vertebrae and cervical curvature, surgical segment were analyzed. Japanese Orthopaedic Association (JOA) scores and its improvement rate were observed before and after operation, and the relationships on the anterior slip of the vertebrae and sagittal plane diagonal diameter of spinal canal, clinical effect were analyzed. RESULTS: All the patients were followed up from 12 to 48 months with an average of 29.5 months. All operative vertebrae occurred anterior slip with different degree after corpectomy surgery, the maximum was 3.52 mm and minimum was 1.12 mm, with an average of (2.14±1.02) mm. According to the clustering method, the anterior slip distance with (3.07±0.21) mm classified as forward greatly group(90 cases, 54.9%) and the anterior slip distance with (1.55±0.32) mm classified as forwad short group(74 cases, 45.1%). There was no significant difference between anterior slip distance and operation segments(χ²=0.01, P=0.996). Cervical curvature index and anterior slip distance of operated vertebra had a positive correlation (r=0.724). The incidence of reduction of the diagonal diameter of cervical spinal canal in forward greatly group was higher than that of forwad short group(χ²=4.45, P=0.035). The patients with unsatisfactory efficacy appeared obvious anterior slip of the vertebrae after corpectomy than the patients with satisfactory efficacy(P<0.05). CONCLUSIONS: Corpectomy of the cervical spine can result in vertebral forward displacement trend, and obvious displacement may cause the secondary compression of the spinal cord.

Nucleus pulposus mesenchymal stem cells in acidic conditions mimicking degenerative intervertebral discs give better performance than adipose tissue-derived mesenchymal stem cells.

The microenvironment of the intervertebral disc (IVD) is characterized by matrix acidity, hypoxia, hyperosmolarity and limited nutrition, which are major obstacles to stem cell-based regeneration. Our recent work showed that nucleus pulposus mesenchymal stem cells (NPMSCs) had advantages over traditional sources of cell therapy under IVD-like hypoxic and hyperosmotic conditions. Here, we examined the viability, proliferation and matrix metabolism of NPMSCs compared with adipose tissue-derived mesenchymal stem cells (ADMSCs) under IVD-like acidic conditions in vitro. ADMSCs and NPMSCs from Sprague-Dawley rats were cultured at four different pH levels representing the standard condition (pH 7.4) and the normal, mildly degenerated and severely degenerated IVD (pH 7.1, 6.8 and 6.5, respectively). Cell viability was examined by annexin-V-fluorescein isothiocyanate/propidium iodide staining. Cell proliferation was measured using a cell counting kit cell proliferation assay. The expression of aggrecan, collagen-I, collagen-II, matrix metalloproteinase-2 (MMP-2), a disintegrin and metalloproteinase with thrombospondin motifs-4 (ADAMTS4) and the tissue inhibitor of metalloproteinase-3 (TIMP-3) was measured at mRNA and protein levels by RT-PCR and Western blotting. In both cell types, acidic pH inhibited cell viability and proliferation, downregulated the expression of aggrecan, collagen-I, collagen-II and TIMP-3, and upregulated the expression of MMP-2 and ADAMTS4. Compared with ADMSCs, NPMSCs were significantly less inhibited in viability and proliferation; they expressed significantly higher levels of aggrecan and collagen-II, and lower levels of MMP-2 and ADAMTS4. Thus, an acidic environment is a major obstacle for IVD regeneration by ADMSCs or NPMSCs. NPMSCs appeared less sensitive to inhibition by acidic pH and might be promising candidates for cell-based IVD regeneration.