The Clinical Effect of Manual Reduction Combined with Internal Fixation Through Wiltse Paraspinal Approach in the Treatment of Thoracolumbar Fracture.

OBJECTIVE: To evaluate the clinical outcome of manual reduction combined with pedicle fixation through Wiltse paraspinal approach (WPA) in the treatment of thoracolumbar fractures. METHODS: From May 2017 to May 2019, 48 thoracolumbar fractures patients without neurological symptoms were enrolled in this study. Forty-eight patients were randomly divided into two groups based on the different surgical treatment. Group 1 was manual reduction combined with pedicle screw fixation through Wiltse paraspinal approach treatment group. Group 2 was pedicle screw fixation through traditional posterior approach treatment group. The operation time (OT), intraoperative blood loss (BL), postoperative drainage (PD), time of brace (TB) and the cobb angle recovery of the injured kyphosis in the prone position were obtained and compared between the two groups, respectively. Comparison of cobb angle changes, serum creatine kinase (CK) level, pain visual analogue score (VAS), Oswestry disability index (ODI), and multifidus cross-sectional (MCS) area changes were achieved between the two groups, respectively. RESULTS: Forty-eight patients were enrolled in this study and each group had 24 patients. There was no significant difference between the two groups in patient's age, height, weight, and body mass index (BMI). There were 20 males and four females in group 1. The mean age, height, weight, and BMI of patients were 61.99 ± 11.00 years (range, 42-75 years), 175.21 ± 4.49 cm, 76.71 ± 4.87 kg, and 24.98 ± 1.03 kg/m2 in group 1, respectively. Group 2 had 18 males and six females, and the mean age, height, weight, and BMI of patients were 57.95 ± 9.22 years (range, 44-77 years), 176.37 ± 4.56 cm, 77.42 ± 4.61 kg, and 24.87 ± 1.10 kg/m2 in group 2, respectively. The mean bleeding volume of group 1 was significantly less than group 2 (64.13 ± 9.77 ml and 152.13 ± 10.73 ml, respectively) (P < 0.05). The mean operation time, postoperative drainage, and time of brace were 62.95 ± 9.80 min, 66.25 ± 12.75 ml, and 3.62 ± 0.97 days in group 1, respectively, and they were significantly better than those of group 2 (69.29 ± 6.82min, 162.96 ± 14.55ml and 7.88 ± 1.94 days, respectively) (P < 0.05). The mean multifidus cross-sectional area was significantly smaller than per-operation after surgery in two groups (P < 0.05). The mean creatine kinase of group 1 was 403.13 ± 39.78 U/L and 292.12 ± 45.81 U/L at 1 and 3 days after surgery, respectively, which was significantly smaller than those in group 2 (654.25 ± 53.13 U/L and 467.67 ± 44.25 U/L, respectively) (P < 0.05). The Oswestry disability index of group 1 were significantly better than those in group 2 especially at 1 month and final follow-up after surgery (P < 0.05). Moreover, group 1 also had better outcomes in postoperative Cobb angle change than those in group 2, with significant difference on intra-operation, 1 day and 1 month post-operation (P < 0.05). CONCLUSION: In short, this operation is suitable for thoracolumbar fractures without neurologic symptoms. Preoperative manual reduction had advantages of restoring the height of injured vertebrae. Wiltse intermuscular approach can reduce intraoperative blood loss, shorten operation time, and reduce paraspinal muscle damage. Using the traditional posterior approach, it is easy for surgeons to grasp this technique and it should be recommended as conforming with the minimally invasive approach of recent years.

Progress in Articular Cartilage Tissue Engineering: A Review on Therapeutic Cells and Macromolecular Scaffolds.

Repair and regeneration of articular cartilage lesions have always been a major challenge in the medical field due to its peculiar structure (e.g., sparsely distributed chondrocytes, no blood supply, no nerves). Articular cartilage tissue engineering is considered as one promising strategy to achieve reconstruction of cartilage. With this perspective, the articular cartilage tissue engineering has been widely studied. Here, the recent progress of articular cartilage tissue engineering is reviewed. The ad hoc therapeutic cells and growth factors for cartilage regeneration are summarized and discussed. Various types of bio/macromolecular scaffolds together with their pros and cons are also reviewed and elaborated.

Reduced inflammatory factor expression facilitates recovery after sciatic nerve injury in TLR4 mutant mice.

Toll-like receptors (TLRs) are extremely significant pattern recognition receptors. When nerve injury occurs, a variety of inflammatory factors are generated, leading to an exceedingly complex micro-environment. TLRs recognize damage-associated molecular patterns. To investigate the correlation between TLR4 and recovery after sciatic nerve injury, the model of sciatic nerve injury was conducted using TLR4-mutated mice (C3H/HeJ) and wild mice (C3H/HeN). Our goal was to identify short-stage and long-stage changes after sciatic nerve injury, mainly by checking the expression changes of inflammation factors in the short-stage and the differences in the recovery of the injured sciatic nerve in the long-stage. The results show that the increase of changes in the HeN group of IL-1ß, IL-6, TNF-α and MCP-1 are more obvious than in the HeJ group, with caspase1 expression higher and Nlrp3 expression lower in the former group. Further results reveal intense inflammation occurred in the HeN group showing more neutrophils and macrophages. Nlrp3 and caspase1 showed little difference by Immunohistochemistry, with Nlrp6 expression differing between the HeJ group and the HeN group. The results led us to conclude that better recovery of the injured sciatic nerve occurred in the HeJ group because the expression of GAP-43 and p75NTR was higher and had a better SFI figure. TLR4 mutation can decrease the expression of inflammatory factors and enhance the speed of recovery after sciatic nerve injury. The changes in the expression of Nlrp6, which are related to the TLR4 mutation, may influence recovery of the injured sciatic nerve. Further studies will be conducted to confirm these results.

Study on salvianolic acid B in the reduction of epidural fibrosis in laminectomy rats.

BACKGROUND: Epidural fibrosis (EF) is a common complication after laminectomy. Salvianolic acid B (Sal B) is a major bioactive component of a traditional Chinese medical agent, Salvia miltiorrhiza, which has shown anti-inflammatory, anti-fibrotic and anti-proliferative properties. The object of this study was to investigate the effect of Sal B on the prevention of epidural fibrosis in laminectomy rats. METHODS: A controlled double-blinded study was conducted in sixty healthy adult Wistar rats that underwent laminectomy at the L1-L2 levels. The rats were randomly divided into 3 groups of 20: (1) Sal B treatment group; (2) Vehicle group; (3) Sham group (laminectomy without treatment). All rats were sacrificed 4 weeks post-operatively. The extent of epidural fibrosis, fibroblast proliferation and the expression of vascular endothelial growth factor (VEGF) and inflammatory factors were analyzed. RESULTS: The recovery of all rats was uneventful. In the laminectomy sites treated with Sal B, the dura mater showed no adhesion. Collagen deposition was significantly lower in the Sal B group than the other two groups. In addition, both fibroblast and inflammatory cell counting in the laminectomy sites treated with Sal B showed better grades than the other two groups. The expression of VEGF and inflammatory factors in operative sites also suggested better results in the Sal B group than the other two groups. CONCLUSIONS: Sal B inhibits fibroblast proliferation, blood vessel regeneration, and inflammatory factor expression. Thus, Sal B is able to prevent epidural scar adhesion in post-laminectomy rats.

Platelet-rich plasma gel in combination with Schwann cells for repair of sciatic nerve injury.

Bone marrow mesenchymal stem cells were isolated from New Zealand white rabbits, culture-expanded and differentiated into Schwann cell-like cells. Autologous platelet-rich plasma and Schwann cell-like cells were mixed in suspension at a density of 1 × 10(6) cells/mL, prior to introduction into a poly (lactic-co-glycolic acid) conduit. Fabricated tissue-engineered nerves were implanted into rabbits to bridge 10 mm sciatic nerve defects (platelet-rich plasma group). Controls were established using fibrin as the seeding matrix for Schwann cell-like cells at identical density to construct tissue-engineered nerves (fibrin group). Twelve weeks after implantation, toluidine blue staining and scanning electron microscopy were used to demonstrate an increase in the number of regenerating nerve fibers and thickness of the myelin sheath in the platelet-rich plasma group compared with the fibrin group. Fluoro-gold retrograde labeling revealed that the number of Fluoro-gold-positive neurons in the dorsal root ganglion and the spinal cord anterior horn was greater in the platelet-rich plasma group than in the fibrin group. Electrophysiological examination confirmed that compound muscle action potential and nerve conduction velocity were superior in the platelet-rich plasma group compared with the fibrin group. These results indicate that autologous platelet-rich plasma gel can effectively serve as a seeding matrix for Schwann cell-like cells to construct tissue-engineered nerves to promote peripheral nerve regeneration.

Computer-assisted virtual surgical procedure for acetabular fractures based on real CT data.

OBJECTIVE: To develop and evaluate a computer-assisted virtual surgical procedure for preoperative planning that simulates the reduction and plate fixation for acetabular fractures based on real computed tomography (CT) data using computer softwares on personal computers. METHODS: Virtual preoperative planning for reduction and plate fixation for seven acetabular fractures was performed. Three-dimensional (3D) models of acetabular fractures based on real CT data in Dicom format were built to perform reduction first. Then fixation was undertaken after plate contouring. Virtual planning was compared with real surgery with respect to operative approach, plate length and screw count. Furthermore, the time required for virtual surgery was recorded. RESULTS: Virtual surgery was successfully achieved and identical to the real operation in all cases. The mean time required was 79 min. CONCLUSION: The virtual surgical procedure for acetabular fractures is feasible and useful clinically for surgeons to determine surgical planning. It may be a valuable tool for surgeons in learning about the nature of the fracture and in formulating an appropriate surgical plan.

Three-dimensional computed tomography imaging increases the reliability of classification systems for tibial plateau fractures.

OBJECTIVE: The purpose of this study was to determine whether three-dimensional reconstructed computed tomography (CT) images can improve intra-observer and inter-observer reliability for classification systems of tibial plateau fractures compared to plain radiographs and two-dimensional CT images. METHODS: Twenty-one tibial plateau fractures were classified independently by four attending orthopaedic trauma surgeons using the AO/ASIF and Schatzker classification systems. First, a combination of plain radiographs and two-dimensional (2D) CT images were evaluated. Second, 4 weeks later, plain radiographs and three-dimensional (3D) CT images were assessed. Then, 4 weeks later, these two rounds of evaluation were repeated. The intra-observer and inter-observer reliability were assessed using kappa statistics. RESULTS: Three-dimensional CT images can improve the inter-observer and intra-observer reliability regarding both AO/ASIF and Schatzker classification systems of tibial plateau fractures compared to 2D CT images. The degree of agreement of the inter-observer and intra-observer reliability among four surgeons increased from 'substantial' to 'almost perfect'. CONCLUSION: Three-dimensional CT is a more reliable radiographic modality than 2D CT in evaluation of fracture patterns in tibial plateau fractures. This finding seems to show that more sophisticated imaging techniques can improve the reliability of fracture classification systems.

[A model of lumbar disc degeneration on the early stage in rhesus monkey with minimally invasive technique].

OBJECTIVE: To establish a novel model of lumbar disc degeneration on the early stage in the rhesus monkey using percutaneous needle puncture guided by CT. METHODS: (1) Thirteen rhesus monkeys aged from 4 to 7 years, female 7 and male 6 were selected for establishing a model of the early stage of lumbar disc degeneration. (2)13 monkeys, 91 discs were divided into 3 groups: 64 discs from L1/2 to L5/6 were percutaneous punctured with a needle 20G as experimental group and 1 disc with a needle 15G as puncture control group and 26 discs were not be punctured from L6,7 to L7-S1 as control group. (3) Lumbar disc localization for needle puncture was guided by CT. All discs were examined by MRI, the HE, Masson's trichrome, Safranine-O and immunohistochemical staining of type II collagen before disc puncture and after puncture at 4, 8 and 12 weeks. RESULTS: MRI: (1) Experimental group: Pfirmann's Grade I was shown at postoperation 4, 8 and 12 weeks; (2) Puncture control group: Grade III was shown at postoperation 4 weeks and Grade IV at 8 weeks; (3) CONTROL GROUP: Grade I was shown at postoperation 4, 8 and 12 weeks. Histological examination: (1) In experimental group, there was no any change at postoperation 4 weeks, and the cell population of the nucleus was decreased at 8 weeks and more decreased at 12 weeks in HE. (2) There was no any change at postoperation 4 weeks, the clefts among the lamellae of the annulus fibrosus (AF) were shown at 8 weeks and more wider of the clefts of AF at 12 weeks in Masson's trichrome. (3) No any change was shown at postoperation 4 weeks, proteoglycan were progressively decreased at 8 and 12 weeks in Safranine-O. (4) No statistically significant difference in positive rate was observed at 4 and 8 weeks compared with control group in immunohistochemical staining of type II collagen. There was statistical difference at 12 weeks compared with control group (P<0.05). In puncture control group postoperation 8 weeks, the morphology of cell of nucleus pulposus was not clear in HE. The wider clefts of lamellae of the AF were shown in Masson's trichrome. The proteoglycan was obviously decreased in Safranine-O. Immunohistochemical staining collagen II synthesized was decreased. In normal control group, no any change was shown at 4, 8 and 12 weeks. CONCLUSIONS: The degeneration of lumbar intervertebral disc on the early stage could be induced by the percutaneous needle puncture (20G) to the annulus fibrosus. The assessment of disc degeneration on early stage is not shown on MRI and only confirmed by histological examination.