Objective To investigate the amount of bone grafting, bone defect gap residual rates, and biomechanical stability of the injured vertebral body after reduction of thoracolumbar burst fractures, pedicle screw-rods fixation, and bone graft by bilateral pedicle or unilateral spinal canal. Methods Eighteen fresh lumbar spine (L1-5) specimens of calves (aged 4-6 months) were collected to establish the burst fracture model at L3 and divided into 3 groups randomly. After reduction and fixation with pedicle screws, no bone graft was given in group A (n=6), and bone graft was performed by bilateral pedicles in group B (n=6) and by unilateral spinal canal in group C (n=6). The amount of bone grafting in groups B and C was recorded. The general situation of bone defect gaps was observed by the DR films and CT scanning, and the defect gap residual rates of the injured vertebrae were calculated with counting of grids. The compression stiffness was measured by ElectreForce-3510 high precision biological material testing machines. Results The amount of bone grafting was (4.58 ± 0.66) g and (5.72 ± 0.78) g in groups B and C respectively, showing signficant difference (t=2.707, P=0.022). DR films and CT scanning observation showed large bone defect gap was seen in injured vertebrae specimens of group A; however, the grafting bone grains was seen in the “eggshell” gap of the injured vertebral body, which were mainly located in the posterior part of the vertebral body, but insufficient filling of bone graft in the anterior part of the vertebral body in group B; better filling of the grafting bone grains was seen in injured vertebral body of group C, with uniform distribution. The bone defect gap residual rates were 52.0% ± 5.5%, 39.7% ± 2.5%, and 19.5% ± 2.5% respectively in groups A, B, and C; group C was significantly lower than groups A and B (P lt; 0.05), and group B was significantly lower than group A (P lt; 0.05). Flexion compressive stiffness of group C was significantly higher than that of groups A and B (P lt; 0.05), but no significant difference was found between groups A and B (P gt; 0.05). Extension compressive stiffness in group C was significantly higher than that in group A (P lt; 0.05), but no significant difference was found between groups A and B, and between groups B and C (P gt; 0.05). The compression stiffness of left bending and right bending had no significant difference among 3 groups (P gt; 0.05). Conclusion Thoracolumbar burst fracture pedicle screws fixation with bone grafting by unilateral spinal canal can implant more bone grains, has smaller bone defect gap residual rate, and better recovery of flexion compression stiffness than by bilateral pedicles.
Objective To study whether human amniotic fluid colony derived stem cells (hAFCSCs) are involved in regeneration of injured muscles in mice and to investigate the method and feasibil ity of hAFCSCs-based cytotherapy in the treatment of injured muscles. Methods Human second-trimester amniotic fluid was collected through ultrasound-guided amniocentesis, hAFCSCs were isolated from second-trimester amniotic fluid and cultured, and the cells at 6th-8th passages were spared. The mRNA was extracted to identify the stem cell related genes by RT-PCR. The muscular injury model of bilateral tibial is anterior muscle was establ ished by cardiotoxin and X-ray irradiation in 16 Nod/Scid mice (aged 6-8 weeks, and weighing 20-24 g). The hAFCSCs (3.3 × 107/mL, 30 μL) were injected into the right injured tibial is anterior muscles as the experimental group, while the same volume of complete medium (α-MEM containing 15%FBS, 18%Chang B, 2%Chang C, 1% penicill instreptomycin, and 1% L-glutamine) was injected into the left injured tibial is anterior muscles as the control group. At 2 and 4 weeks after cell transplantation, the immunofluorescence staining of tibial is anterior muscles was performed to detect hepatocyte growth factor receptor (c-Met), myogenic regulatory factor (Myf-5), Laminin, Desmin, and human specific nuclear mitotic apparatus protein (NuMa). Results The clone formation was observed at 5-7 days of primary hAFCSCs culture; after 8-10 days, the clones with homogeneous morphology were selected for subculture. Adequate stem cells were available after 6th-8th subculture. RT-PCR analysis showed that hAFCSCs expressed mRNA of the stem cell related genes. The immunofluorescence double-staining showed that NuMa expressed in tibial is anterior muscles of the experimental group and no myogenic phenotype expressed at 2 weeks after cell transplantation, and that single cell co-expressed NuMa and c-Met or Myf-5 at 4 weeks after cell transplantation. In some myofibers, NuMa and Laminin or Desmin were also co-expressed. No NuMa positive hAFCSCs were detected in the control group at 2 and 4 weeks after cell transplantation. Conclusion hAFCSCs can participate in the regeneration of injured mouse muscle.
Objective To investigate whether the Runx2 gene can induce the differentiation of human amniotic mesenchymal stem cells (hAMSCs) to ligament fibroblasts in vitro and promote the tendon-bone healing in rabbits. Methods hAMSCs were isolated from the placentas voluntarily donated from healthy parturients and passaged, and then identified by flow cytometric identification. Adenoviral vectors carrying Runx2 gene (Ad-Runx2) and empty vector adenovirus (Ad-NC) were constructed and viral titer assay; then, the 3rd generation hAMSCs were transfected with Ad-Runx2 (Ad-Runx2 group) or Ad-NC (Ad-NC group). The real-time fluorescence quantitative PCR and Western blot were used to detect Runx2 gene and protein expression to verify the effectiveness of Ad-Runx2 transfection of hAMSCs; and at 3 and 7 days after transfection, real-time fluorescence quantitative PCR was further used to detect the expressions of ligament fibroblast-related genes [vascular endothelial growth factor (VEGF), collagen type Ⅰ, Fibronectin, and Tenascin-C]. The hAMSCs were used as a blank control group. The hAMSCs, hAMSCs transfected with Ad-NC, and hAMSCs were mixed with Matrigel according to the ratio of 1 : 1 and 1 : 2 to construct the cell-scaffold compound. Cell proliferation was detected by cell counting kit 8 (CCK-8) assay, and the corresponding cell-scaffold compound with better proliferation were taken for subsequent animal experiments. Twelve New Zealand white rabbits were randomly divided into 4 groups of sham operation group (Sham group), anterior cruciate ligament reconstruction group (ACLR group), anterior cruciate ligament reconstruction+hAMSCs transfected with Ad-NC-scaffold compound group (Ad-NC group), and anterior cruciate ligament reconstruction+hAMSCs transfected with Ad-Runx2-scaffold compound group (Ad-Runx2 group), with 3 rabbits in each group. After preparing the ACL reconstruction model, the Ad-NC group and the Ad-Runx2 group injected the optimal hAMSCs-Matrigel compunds into the bone channel correspondingly. The samples were taken for gross, histological (HE staining and sirius red staining), and immunofluorescence staining observation at 1 month after operation to evaluate the inflammatory cell infiltration as well as collagen and Tenascin-C content in the ligament tissues. ResultsFlow cytometric identification of the isolated cells conformed to the phenotypic characteristics of MSCs. The Runx2 gene was successfully transfected into hAMSCs. Compared with the Ad-NC group, the relative expressions of VEGF and collagen type Ⅰ genes in the Ad-Runx2 group significantly increased at 3 and 7 days after transfection (P<0.05), Fibronectin significantly increased at 3 days (P<0.05), and Tenascin-C significantly increased at 3 days and decreased at 7 days (P<0.05). CCK-8 detection showed that there was no significant difference (P>0.05) in the cell proliferation between groups and between different time points after mixed culture of two ratios. So the cell-scaffold compound constructed in the ratio of 1∶1 was selected for subsequent experiments. Animal experiments showed that at 1 month after operation, the continuity of the grafted tendon was complete in all groups; HE staining showed that the tissue repair in the Ad-Runx2 group was better and there were fewer inflammatory cells when compared with the ACLR group and the Ad-NC group; sirius red staining and immunofluorescence staining showed that the Ad-Runx2 group had more collagen typeⅠ and Ⅲ fibers, tending to form a normal ACL structure. However, the fluorescence intensity of Tenascin-C protein was weakening when compared to the ACLR and Ad-NC groups. Conclusion Runx2 gene transfection of hAMSCs induces directed differentiation to ligament fibroblasts and promotes tendon-bone healing in reconstructed anterior cruciate ligament in rabbits.
Objective To evaluate the early-term effectiveness of Latarjet procedure with double EndoButtons fixation for recurrent anterior shoulder dislocation by coracoid osteotomy with preserving coracoacromial ligament. Methods Between January 2021 and June 2023, 19 patients with recurrent anterior shoulder dislocations were treated by arthroscopic Latarjet procedure with double EndoButtons fixation, all of which underwent coracoid osteotomy with preserving the coracoacromial ligament. There were 11 males and 8 females, with an average age of 23.3 years (range, 17-32 years). Shoulder dislocations ranged from 3 to 11 times, with an average of 6.4 times. The disease duration ranged from 3 to 35 months, with an average of 12.9 months. All apprehension tests were positive. Imaging examination showed that the defect width of the ipsilateral glenoid bone was 13%-26%, with an average of 19.8%. After operation, the shoulder range of motion was examined, including flexion lift, lateral external rotation, extension 90° external rotation, and internal rotation. Shoulder joint function was evaluated by Walch-Duplay score, American Association for Shoulder and Elbow Surgery (ASES) score, and Rowe score. Imaging examinations were taken to observe the position and shaping of coracoid. Results All incisions healed by first intention and no nerve or vessel injury occurred. All patients were followed up 9-24 months (mean, 14.5 months). There was no recurrence of shoulder dislocation and the apprehension tests were negative during follow-up. There was no significant difference in the shoulder range of motion (flexion lift, lateral external rotation, extension 90° external rotation, and internal rotation) between preoperation and at last follow-up (P>0.05). The Walch-Duplay score, ASES score, and Rowe score significantly improved when compared with those before operation (P<0.05). Postoperative imaging showed that coracoid graft was at the same level with the glenoid in all cases; the center of coracoid graft was located between 3 to 5 o’clock. During follow-up, there was no glenohumeral joint degeneration, the acromiaohumeral distance was not reduced when compared with preoperation, and the coracoid bone gradually formed concentric circles with the humeral head. Conclusion The Latarjet procedure with double EndoButtons fixation can effectively treat recurrent anterior shoulder dislocation by coracoid osteotomy with preserving coracoacromial ligament, and the early-term effectiveness is satisfactory.
Objective To investigate the expression and prolyl hydroxylase (PHD)2 in retina of diabetic rats．Methods Wistar rats were randomly divided into the control group (n=48) and the diabetes group (n=60). The rats in diabetes group were induced with streptozotocin (STZ) injection creating a diabetic retinopathy model. The same volume of citric acid buffer was injected into the rats in the control group. Fluorescence microscope was used to observe the retinal vasculature at one, three and six months after injection. Evans blue perfusion was used to detect the bloodretinal barrier (BRB) permeability. Immunohistochemical staining was used to observe the distribution of PHD-2 positive staining. Western blot was used to measure the protein expression of PHD-2, hypoxia inducible factor（HIF）-1alpha; and vascular endothelial growth factor (VEGF) every month from one to six months after injection. Results The vascularization was normal and form was clear in retina of rats in control group. The retinal blood vessels of rats in diabetes group showed significantly increased fluorescence. Compared with the control group, the BRB permeability was significantly increased in diabetes group (P＜0.05). Abundant expression of PHD-2 protein was detected in the inner layers of retina in control and diabetes group．Compared with the control group, the PHD-2 expression was decreased in diabetes group at one and two months after injection (t=16.230, 16.390;P＜0.05). The HIF-1alpha; expression was significantly increased in diabetes group at one, two and three months after injection (t=27.073, 36.709, 10.176; P＜0.05). The VEGF expression was significantly increased in diabetes group every month from one to six months after injection (t=13.547, 31.984, 21.897, 8.912, 9.019, 14.046; P＜0.05). Conclusions There is abundant expression of PHD-2 in the inner layer of retina in diabetic rats. PHD-2 may play an important role in diabetic retinopathy, which is correlated with VEGF．
Objective To summarize mid-term effectiveness of modified arthroscopic suture button fixation Latarjet procedure for treatment of recurrent anterior shoulder dislocations. Methods Between January 2018 and October 2020, 30 patients with recurrent anterior shoulder dislocations were treated with modified arthroscopic suture button fixation Latarjet procedure. There were 19 males and 11 females with an average age of 27.3 years (range, 18-41 years). The shoulder dislocation occurred 3-7 times, with an average of 4.9 times. The time from the last dislocation to operation was 3-10 days, with an average of 4.1 days. Glenoid defects exceeded 20% in all cases. There were 27 cases of Hill-Sachs lesions. The joint pain and function were estimated by visual analogue scale (VAS) score, University of California, Los Angeles (UCLA) score, Rowe score, American Association for Shoulder and Elbow Surgery (ASES) score, Walch-Duplay score, and the range of external rotation at 0° and external rotation at 90° abduction of shoulder before operation and at 1 month, 6 months, and last follow-up. The X-ray film, CT scan and three-dimensional reconstruction were reviewed to observe the position, healing, and absorption of the coracoid graft, correction of glenoid defect, and joint degeneration.Results The operation time ranged from 51 to 79 minutes, with an average of 68.4 minutes. All incisions healed without complications such as nerve or blood vessel injury. All patients were followed up 36-60 months with an average of 44.6 months. The VAS score, UCLA score, Rowe score, ASES score, Walch-Duplay score, and the range of external rotation at 0° and external rotation at 90° abduction after operation significantly improved when compared with preoperative values (P<0.05). All indicators further improved with time, and the differences between different time points after operation were significant (P<0.05). Imaging review showed that the coracoid graft was located in the anteroinferior glenoid at 1 day after operation, and no occurrence of shoulder osteoarthritis was found during follow-up. The anatomical structure of the glenoid was normal, and no delayed healing or non-union of the coracoid graft occurred. At 20 months after operation, arthroscopic re-exploration was performed in 1 case due to fracutre caused by falling injury revealed the good shaping of the coracoid graft, smooth glenoid, and no bone resorption or osteoarthritis. ConclusionFor recurrent anterior shoulder dislocations, the modified arthroscopic suture button fixation Latarjet procedure can obtain good recovery of shoulder function and low incidence of complications and has a good mid-term effectiveness.
Objective To investigate the efficacy on clinical condition assessment and the safety of ultrasound-guided osteofascial chamber puncture manometry in evaluating the pressure of the osteofascial chamber in patients with venomous snake bites. Methods Patients with venomous snake bites admitted to the Department of Emergency Medicine of West China Hospital of Sichuan University between April 2021 and January 2023 were prospectively included, and their basic information, physiological indicators (heart rate, blood pressure), laboratory examination indicators, physical signs, treatment methods and prognosis were collected. The patients whose extremal pressure was measured by osteofascial chamber puncture under ultrasound guidance were selected as the manometry group. Patients who were bitten by venomous snakes at the same time without puncture pressure measurement were randomly selected as the control group at a ratio of 1∶1. The bleeding, infection, nerve injury, length of hospital stay and long-term prognosis of the two groups were compared to explore the safety of ultrasound-guided osteofascial chamber puncture manometry. The correlation between the pressure measured in the manometry group and creatine kinase (a representative index of acute poisoning severity score) was analyzed to explore the efficacy of ultrasound-guided osteofascial chamber puncture manometry in evaluating the disease. Results There was no significant difference between the manometry group and the control group in new or aggravated infection, bleeding, nerve injury (such as numbness and anesthesia), hospital treatment time, final detumescence time of the affected limb, or final adverse prognosis (P>0.05). There was a positive correlation between the measured pressure and creatine kinase (rs=0.286, P=0.002). Conclusions The higher pressure measured by ultrasound-guided osteofascial chamber puncture manometry is, the more serious the poisoning condition may be. In addition, ultrasound-guided osteofascial chamber puncture manometry does not prolong the hospital time of patients or the final swelling reduction time of the affected limb, and does not increase the incidence of bleeding, infection, nerve damage or eventual adverse prognosis events. It has clinical practicability and feasibility.