Use of problem-based learning in orthopaedics education: a systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: Currently, problem-based learning (PBL) has been widely used in many disciplines, but no systematic review has explored the advantages and disadvantages of PBL in orthopaedics education. METHODS: We searched the PubMed, Cochrane Library, Embase, Web of Science, Scopus, Chongqing VIP Database (VIP), Chinese National Knowledge Infrastructure (CNKI), and Wanfang databases up to April 2023 to identify for relevant studies. Relevant studies were identified by using specific eligibility criteria, and data were extracted. RESULTS: A total of 51 randomized controlled trials with 4268 patients were included. Compared with traditional education, PBL teaching yielded significantly higher knowledge scores (SMD=1.10, 95% CI: 0.78~1.41, P<0.00001), procedural skill scores and clinical skill scores than traditional teaching (SMD=2.07, 95% CI: 1.61~2.53, P<0.00001; SMD=1.20, 95% CI: 0.88~1.52, P<0.00001). Moreover, the total scores were higher in the PBL teaching group than in the traditional teaching group (MD=5.69, 95% CI: 5.11~6.26, P<0.00001). Students also expressed higher levels of interest and satisfaction in the PBL teaching group than in the traditional teaching group (OR=4.70, 95% CI: 3.20~6.93, P<0.00001; OR=5.43, 95% CI: 3.83~7.69, P<0.00001). However, there was less learning time and higher levels of learning pressure in the PBL teaching group (OR=0.12, 95% CI: 0.06~0.24, P<0.00001; OR=5.95, 95% CI: 3.16~11.23, P<0.00001). CONCLUSION: Current evidence indicates that PBL teaching can increase knowledge scores, procedural skill scores, and clinical skill scores. Students have higher levels of interest in teaching and higher levels of teaching satisfaction in the PBL group. However, students can feel higher levels of study pressure and experience less study time. The findings of the current study need to be further verified in multicentre, double-blind and large-sample RCTs.

Learning active sensing strategies using a sensory brain-machine interface.

Diverse organisms, from insects to humans, actively seek out sensory information that best informs goal-directed actions. Efficient active sensing requires congruity between sensor properties and motor strategies, as typically honed through evolution. However, it has been difficult to study whether active sensing strategies are also modified with experience. Here, we used a sensory brain-machine interface paradigm, permitting both free behavior and experimental manipulation of sensory feedback, to study learning of active sensing strategies. Rats performed a searching task in a water maze in which the only task-relevant sensory feedback was provided by intracortical microstimulation (ICMS) encoding egocentric bearing to the hidden goal location. The rats learned to use the artificial goal direction sense to find the platform with the same proficiency as natural vision. Manipulation of the acuity of the ICMS feedback revealed distinct search strategy adaptations. Using an optimization model, the different strategies were found to minimize the effort required to extract the most salient task-relevant information. The results demonstrate that animals can adjust motor strategies to match novel sensor properties for efficient goal-directed behavior.

Stealth Strategies of Mycobacterium tuberculosis for Immune Evasion.

Tuberculosis is a devastating disease causing high mortality all over the world, especially in the developing countries. Mycobacterium tuberculosis (M. tb) is the causative agent of tuberculosis which replicates in the intracellular environment of host macrophages. Although the host immune system is capable of completely eliminating the pathogen, co-evolution of M. tb with humans has resulted in its ability to hijack the host innate and adaptive immune systems in numerous ways. Limited recent progress has been made in the understanding of M. tb immune escape mechanisms, hence exploration of survival strategies of M. tb has been critically reviewed with an insight into understanding its pathogenesis. We summarized the recent studies regarding the modulation of innate immune response, adaptive immune response, epigenetics and the role of miRNA. All of these advancements suggest that M. tb is well-familiarize with the host immune system and possess the ability to hijack it for intracellular survival.

MC1R Is a Prognostic Marker and Its Expression Is Correlated with MSI in Colorectal Cancer.

Melanocortin 1 receptor (MC1R) is thought to be a marker of poor prognosis and a potential target for the treatment of melanoma. Studies have found that MC1R promotes several tumor behaviors, including cell proliferation and differentiation, pigment formation, and genome damage repair. Some single-nucleotide polymorphisms (SNPs) of MC1R are involved in the occurrence and development of melanoma. A few studies have reported a relationship between MC1R and colorectal cancer (CRC). In this research, our objective was to examine MC1R expression and MC1R SNPs and investigate their correlation with the clinicopathological features of human CRC tissues. We evaluated MC1R mRNA expression by performing bioinformatic analyses on human CRC expression datasets. We used Western blotting and RT-qPCR to compare MC1R expression in CRC tissues with that in normal tissues, and MC1R SNPs in CRC tissues were detected by PCR-direct sequencing (DS). The expression of MC1R was significantly decreased in CRC tissues compared with normal tissue, and its expression was negatively associated with P53 expression, MLH1 expression, and PMS2 expression, and high MC1R expression was significantly associated with microsatellite instability (MSI). MC1R SNPs were also associated with the clinicopathological characteristics of CRC; for example, the rs2228479 locus genotype was correlated with Ki67 status, and the rs885479 locus genotype was correlated with age and T stage. In conclusion, MC1R plays a crucial role in the progression of CRC and may be a marker of poor prognosis in CRC.

Transcription elongation factor A-like 7, regulated by miR-758-3p inhibits the progression of melanoma through decreasing the expression levels of c-Myc and AKT1.

BACKGROUND: Ectopic expression of transcription elongation factor A (SII)-like 7 (TCEAL7) has been observed in several kinds of cancers, but its role in melanoma is still unclear. This study was carried out to investigate TCEAL7 role in melanoma progression, and uncover the underlying mechanisms. METHODS: TCEAL7 expression levels in melanoma tissues and cells were determined by using real-time quantitative PCR (RT-PCR) and western blotting. CCK-8, transwell chambers, flow cytometry, starch assay and tumorigenesis assay were applied to detect cell growth, invasion, apoptosis, migration and tumorigenesis, respectively. RESULTS: A low expression level of TCEAL7 was observed in melanoma tissues and cells, which was associated with malignant clinical process and poor prognosis. TCEAL7 negatively modulated AKT1, AKT2, c-Myc, N-cadherin and PCNA expression and inhibited cancer progression via decreasing AKT1 and c-Myc levels. In addition, TCEAL7 was negatively modulated by miR-758-3p which promoted melanoma progression. Moreover, overexpression of TCEAL7 abolished miR-758-3p role in promoting melanoma progression. CONCLUSION: This study demonstrated that TCEAL7, regulated by miR-758-3p inhibited melanoma progression through decreasing the expression levels of c-Myc and AKT1.

Lactic acid promotes metastatic niche formation in bone metastasis of colorectal cancer.

BACKGROUND: To investigate the effect of lactic acid (LA) on the progression of bone metastasis from colorectal cancer (CRC) and its regulatory effects on primary CD115 (+) osteoclast (OC) precursors. METHODS: The BrdU assay, Annexin-V/PI assay, TRAP staining and immunofluorescence were performed to explore the effect of LA on the proliferation, apoptosis and differentiation of OC precursors in vitro and in vivo. Flow cytometry was performed to sort primary osteoclast precursors and CD4(+) T cells and to analyze the change in the expression of target proteins in osteoclast precursors. A recruitment assay was used to test how LA and Cadhein-11 regulate the recruitment of OC precursors. RT-PCR and Western blotting were performed to analyze the changes in the mRNA and protein expression of genes related to the PI3K-AKT pathway and profibrotic genes. Safranin O-fast green staining, H&E staining and TRAP staining were performed to analyze the severity of bone resorption and accumulation of osteoclasts. RESULTS: LA promoted the expression of CXCL10 and Cadherin-11 in CD115(+) precursors through the PI3K-AKT pathway. We found that CXCL10 and Cadherin-11 were regulated by the activation of CREB and mTOR, respectively. LA-induced overexpression of CXCL10 in CD115(+) precursors indirectly promoted the differentiation of osteoclast precursors through the recruitment of CD4(+) T cells, and the crosstalk between these two cells promoted bone resorption in bone metastasis from CRC. On the other hand, Cadherin-11 mediated the adhesion between osteoclast precursors and upregulated the production of specific collagens, especially Collagen 5, which facilitated fibrotic changes in the tumor microenvironment. Blockade of the PI3K-AKT pathway efficiently prevented the progression of bone metastasis caused by lactate. CONCLUSION: LA promoted metastatic niche formation in the tumor microenvironment through the PI3K-AKT pathway. Our study provides new insight into the role of LA in the progression of bone metastasis from CRC. Video Abstract.

Pseudomonas Exotoxin A-Based Immunotherapy Targeting CCK2R-Expressing Colorectal Malignancies: An In Vitro and In Vivo Evaluation.

Cholecystokinin-2 receptor (CCK2R) has been proven to be a specific biomarker for colorectal malignancies. Immunotoxins are a valuable class of immunotherapy agents consisting of a targeting element and a bacterial or plant toxin. Previous work demonstrated that targeting CCK2R is a good therapeutic strategy for the treatment of colorectal cancer (CRC). In the present study, we developed a new version of CCK2R-targeting immunotoxin GD9P using a targeted peptide, GD9, as the binding motif and a truncated Pseudomonas exotoxin A (PE38) as the cytokiller. BALB/c nude mice were treated with different doses of GD9P, and pharmacodynamics, pharmacokinetic, and toxicological data were obtained throughout this study. Compared to the parental immunotoxin rCCK8PE38, GD9P exhibited about 1.5-fold yield, higher fluorescence intensity, and increased antitumor activity against human CRC in vitro and in vivo. The IC50 values of GD9P in vitro ranged from 1.61 to 4.55 nM. Pharmacokinetic studies were conducted in mice with a T1/2 of 69.315 min. When tumor-bearing nude mice were treated with GD9P at doses ≥2 mg/kg for five doses, a rapid shrinkage in tumor volume and, in some cases, complete remission was observed. A preliminary safety evaluation demonstrated a good safety profile of GD9P as a Pseudomonas exotoxin A-based immunotherapy. The therapy in combination with oxaliplatin can increase the antitumor efficacy and reduce the toxic side effects caused by chemotherapy. In conclusion, the data support the use of GD9P as a promising immunotherapy targeting CCK2R-expressing colorectal malignancies.

Bone mesenchymal stem cells attenuate radicular pain by inhibiting microglial activation in a rat noncompressive disk herniation model.

Spinal disk herniation can induce radicular pain through chemical irritation caused by proinflammatory and immune responses. Bone marrow mesenchymal stem cells (BMSCs) are a unique type of adult stem cell with the functions of suppressing inflammation and modulating immune responses. This study was undertaken to observe the effect of intrathecal BMSCs on the treatment of mechanical allodynia and the suppression of microglial activation in a rat noncompressive disk herniation model. The model was induced by the application of nucleus pulposus (NP) to the L5 dorsal root ganglion (DRG). The study found that the use of NP in the DRG can induce abnormal mechanical pain, increase the contents of the proinflammatory factors TNF-α and IL-1ß, decrease the content of the anti-inflammatory cytokine TGF-ß1 and activate microglia in the spinal dorsal horns (L5) (P < 0.05). BMSC administration could increase the mechanical withdrawal thresholds dramatically, decrease the contents of IL-1ß and TNF-α, increase the content of TGF-ß1 significantly (P < 0.05) and inhibit microglial activation in the bilateral spinal dorsal horn. Our results indicate that BMSC administration can reduce mechanical allodynia and downregulate the expression of proinflammatory cytokines by inhibiting microglial activation in the spinal dorsal horn in a rat noncompressive disk herniation model.

Molecular characterization and differential expression analysis of interleukin 1ß from Ovis aries.

The interleukin-1 family is an important component of the innate immune system and plays an important role in regulating immune responses on the invasion of intracellular parasites in the acquired immune system. Interleukin 1ß (IL-1ß) is one of the members of the IL-1 family that predominantly activates downstream signaling pathways to play immunological functions of stimulating T and B lymphocyte activation and promoting the various syntheses of inflammatory substances in conjunction with other cytokines. Here, a full-length IL-1ß cDNA (OaIL-1ß) of sheep (Ovis aries) was cloned using rapid amplification of cDNA ends (RACE), which consists of 1494 bp and contains a 5'-UTR region with a length of 83 bp, a complete ORF of 801 bp in length, and a 3'-UTR region with a length of 642 bp. Recombinant protein OaIL-1ß was expressed and purified, and the monoclonal antibody against IL-1ß of sheep is prepared. Western blotting results showed that the sheep IL-1ß protein was detected in the heart, liver, lung, kidney, stomach, intestine, muscle, lymph nodes and leukocytes with the highest expression in the muscle and the lowest expression in the lung. Different bacteria treating sheep white blood cells induced differential expression of OaIL-1ß. Compared with the normal sheep, OaIL-1ß in the buffy coat was differentially expressed in the Brucella melitensis-challenged group and the B. suis S2 strain-inoculated group. However, whether IL-1ß may be considered as a molecular biomarker for differing Brucella-infected animals from brucellosis-vaccinated animals or not need to be further studied.

Hippocampal gamma-slow oscillation coupling in macaques during sedation and sleep.

Behavioral and neurophysiological evidence suggests that the slow (≤1 Hz) oscillation (SO) during sleep plays a role in consolidating hippocampal (HIPP)-dependent memories. The effects of the SO on HIPP activity have been studied in rodents and cats both during natural sleep and during anesthetic administration titrated to mimic sleep-like slow rhythms. In this study, we sought to document these effects in primates. First, HIPP field potentials were recorded during ketamine-dexmedetomidine sedation and during natural sleep in three rhesus macaques. Sedation produced regionally-specific slow and gamma (∼40 Hz) oscillations with strong coupling between the SO phase and gamma amplitude. These same features were seen in slow-wave sleep (SWS), but the coupling was weaker and the coupled gamma oscillation had a higher frequency (∼70 Hz) during SWS. Second, electrical stimuli were delivered to HIPP afferents in the parahippocampal gyrus (PHG) during sedation to assess the effects of sleep-like SO on excitability. Gamma bursts after the peak of SO cycles corresponded to periods of increased gain of monosynaptic connections between the PHG and HIPP. However, the two PHG-HIPP connectivity gains during sedation were both substantially lower than when the animal was awake. We conclude that the SO is correlated with rhythmic excitation and inhibition of the PHG-HIPP network, modulating connectivity and gamma generators intrinsic to this network. Ketamine-dexmedetomidine sedation produces a similar effect, but with a decreased contribution of the PHG to HIPP activity and gamma generation.

Layer-by-layer self-assembled multilayers on PEEK implants improve osseointegration in an osteoporosis rabbit model.

This study aims to fabricate and deposit nanoscale multilayers on polyetheretherketone (PEEK) to improve cell adhesion and osseointegration. Bio-activated PEEK constructs were designed with prepared surface of different layers of polystyrene sulfonate (PSS) and polyallylamine hydrochloride (PAH) multilayers. Irregular morphology was found on the 5 and 10-layer PEEK surfaces, while "island-like" clusters were observed for 20-layer (20 L) multilayers. Besides, the 20 L PEEK showed more hydrophilic feature than native PEEK, and the surface contact angle reduced from 39.7° to 21.7° as layers increased from 5 to 20. In vitro, modified PEEK allowed excellent adhesion and proliferation of bone marrow stromal cells, and induced higher cell growth rate and alkaline phosphatase level. In vivo, this bio-active PEEK exhibited significantly enhanced integration with bone tissue in an osteoporosis rabbit model. This work highlights layer-by-layer self-assembly as a practical method to construct bio-active PEEK implants for enhanced osseointegration.

Biomechanical comparison of multilevel lateral interbody fusion with and without supplementary instrumentation: a three-dimensional finite element study.

BACKGROUND: Lateral lumbar interbody fusion (LLIF) is a popular, minimally invasive technique that is used to address challenging multilevel degenerative spinal diseases. It remains controversial whether supplemental instrumentation should be added for multilevel LLIF. In this study, we compared the kinematic stability afforded by stand-alone lateral cages with those supplemented by bilateral pedicle screws and rods (PSR), unilateral PSR, or lateral plate (LP) fixation using a finite-element (FE) model of a multi-level LLIF construct with simulated osteoporosis. Additionally, to evaluate the prospect of cage subsidence, the stress change characteristics were surveyed at cage-endplate interfaces. METHODS: A nonlinear 3-dimensional FE model of the lumbar spine (L2 to sacrum) was used. After validation, four patterns of instrumented 3-level LLIF (L2-L5) were constructed for this analysis: (a) 3 stand-alone lateral cages (SLC), (b) 3 lateral cages with lateral plate and two screws (parallel to endplate) fixated separately (LPC), (c) 3 lateral cages with bilateral pedicle screw and rod fixation (LC + BPSR), and (d) 3 lateral cages with unilateral pedicle and rod fixation (LC + UPSR). The segmental and overall range of motion (ROM) of each implanted condition were investigated and compared with the intact model. The peak von Mises stresses upon each (superior) endplate and the stress distribution were used for analysis. RESULTS: BPSR provided the maximum reduction of ROM among the configurations at every plane of motion (66.7-90.9% of intact spine). UPSR also provided significant segmental ROM reduction (45.0-88.3%). SLC provided a minimal restriction of ROM (10.0-75.1%), and LPC was found to be less stable than both posterior fixation (23.9-86.2%) constructs. The construct with stand-alone lateral cages generated greater endplate stresses than did any of the other multilevel LLIF models. For the L3, L4 and L5 endplates, peak endplate stresses caused by the SLC construct exceeded the BPSR group by 52.7, 63.8, and 54.2% in flexion, 22.3, 40.1, and 31.4% in extension, 170.2, 175.1, and 134.0% in lateral bending, and 90.7, 45.5, and 30.0% in axial rotation, respectively. The stresses tended to be more concentrated at the periphery of the endplates. CONCLUSIONS: SLC and LPC provided inadequate ROM restriction for the multilevel LLIF constructs, whereas lateral cages with BPSR or UPSR fixation provided favorable biomechanical stability. Moreover, SLC generated significantly higher endplate stress compared with supplemental instrumentation, which may have increased the risk of cage subsidence. Further biomechanical and clinical studies are required to validate our FEA findings.

Current applications of robotics in spine surgery: a systematic review of the literature.

OBJECTIVE Surgical robotics has demonstrated utility across the spectrum of surgery. Robotics in spine surgery, however, remains in its infancy. Here, the authors systematically review the evidence behind robotic applications in spinal instrumentation. METHODS This systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Relevant studies (through October 2016) that reported the use of robotics in spinal instrumentation were identified from a search of the PubMed database. Data regarding the accuracy of screw placement, surgeon learning curve, radiation exposure, and reasons for robotic failure were extracted. RESULTS Twenty-five studies describing 2 unique robots met inclusion criteria. Of these, 22 studies evaluated accuracy of spinal instrumentation. Although grading of pedicle screw accuracy was variable, the most commonly used method was the Gertzbein and Robbins system of classification. In the studies using the Gertzbein and Robbins system, accuracy (Grades A and B) ranged from 85% to 100%. Ten studies evaluated radiation exposure during the procedure. In studies that detailed fluoroscopy usage, overall fluoroscopy times ranged from 1.3 to 34 seconds per screw. Nine studies examined the learning curve for the surgeon, and 12 studies described causes of robotic failure, which included registration failure, soft-tissue hindrance, and lateral skiving of the drill guide. CONCLUSIONS Robotics in spine surgery is an emerging technology that holds promise for future applications. Surgical accuracy in instrumentation implanted using robotics appears to be high. However, the impact of robotics on radiation exposure is not clear and seems to be dependent on technique and robot type.

Simple, specific, sensitive and rapid loop-mediated method for detecting Yersinia enterocolitica.

Yersinia enterocolitica (YE) is a main pathogenic bacterium causing diarrhea and yersiniosis occurs in both developed and developing countries with high incidence. YE in contaminated food is able to survive for a long duration even under cold storage, thereby enhancing the risk of food infection. In this study, a new loop-mediated isothermal amplification (LAMP) method showing the characteristics of simplicity, rapidity, high specificity and sensitivity was established by targeting outL of pathogenic YE. Two inner-primers and outer-primers were designed and LAMP reaction was optimized for Mg2+, betaine, dNTPs and inner primers concentrations, reaction temperature and time. Sensitivity and specificity of the LAMP assay was evaluated using YE genomic DNA and those of 44 different bacteria strains, respectively. Validation of LAMP detection method was by employing meat samples spiked with varying CFU of YE. The optimized LAMP assay was specific, capable of detecting 97 fg of genomic DNA (equivalent to 37 genome copies) of YE (100-fold more sensitive than PCR) and 80 CFU/ml of YE-spiked meat samples based on ethidium bromide stained amplicon bands on agarose gel-electrophoresis and on GelRed fluorescence of the LAMP reaction solution, respectively. This rapid, sensitive and specific LAMP technique should enable application in field inspection of Y. enterocolitica in food.

Pulmonary sarcomatoid carcinoma: A rare case report, diagnostic dilemma and review of literature.

RATIONALE: Pulmonary sarcomatoid carcinoma (PSC), a rare tumor, comprises 0.1% to 0.4% of all malignant lung tumors. Given the rarity of PSC, its clinical course, therapeutic guidelines, and patient outcomes remain largely unknown. Therefore, it is imperative to alert clinicians to this extremely rare and instructive early-onset cancer. PATIENT CONCERNS: This report describes a 28-year-old woman with PSC, who was initially misdiagnosed with Whipple's disease. A conclusive diagnosis of PSC was made following careful clinical examination, imaging, and histopathological evaluation of the patient's biopsy sample. Radiological imaging revealed multiple nodules and mass formations in the left upper lobe of the patient's lung, with the largest measuring of 5.4 × 3.2 cm. DIAGNOSIS: Histopathological examination indicated the presence of a malignant neoplasm associated with necrosis suggestive of sarcoma, which was pathologically staged as cT4N1M1. INTERVENTIONS AND OUTCOMES: A regimen of doxorubicin and ifosfamide was administered therapeutically, resulting in a stable disease state. LESSONS: The rarity and tumor origin challenge the diagnosis, which emphasizes the imperative role of histological examination, immunohistochemistry, and flow cytometry in achieving an accurate diagnosis. This report summarizes the existing publications to provide a comprehensive overview of PSC, including its clinical manifestations, radiographic imaging, pathologic features, diagnostic challenges, treatment strategies, and prognosis, and aims to improve the understanding of PSC.

[Osteogenetic capacity of cross-linked adjustable anti-tuberculosis drug sustained-release artificial composite].

OBJECTIVE: To explore the osteogenetic capacity of cross-linked adjustable anti-tuberculosis drug sustained-release artificial composite (TPB/SA-RFP/PLA). METHODS: The model of femur bone defect was established in rabbits.TPB/SA-RFP/PLA complex was implanted into defect parts in the experimental group while TPB/SA/PLA in the blank control group. At Weeks 4, 8 and 12, gross specimens received radiographic, histological and immunohistochemical examinations to determine the osteogenetic performance of TPB/SA-RFP/PLA. RESULTS: As compared with the control group, TPB/SA-RFP/PLA complex had excellent osteogenic capacities while the TPB/SA/PLA group had no obvious osteogenic difference. Lane-sandhu histological and radiographic ratings demonstrated significant difference between TPB/SA-RFP/PLA (8.3 ± 0.3) and blank groups (2.2 ± 0.4) (P < 0.05). And TPB/SA/PLA showed no significant intragroup significance (P > 0.05). Two groups immunohistochemical Alkaline phosphatase was strongly positive in two test groups and weakly positive in the control group. CONCLUSION: TPB/ SA-RFP/PLA has excellent profiles of bone conductivity and regeneration.And the incorporation of rifampin does not affect its osteogenetic capacity.

Advances in the regulation of adipogenesis and lipid metabolism by exosomal ncRNAs and their role in related metabolic diseases.

Exosomes are membrane-bound extracellular vesicles released following the fusion of multivesicular bodies (MVBs) with the cell membrane. Exosomes transport diverse molecules, including proteins, lipids, DNA and RNA, and regulate distant intercellular communication. Noncoding RNA (ncRNAs) carried by exosomes regulate cell-cell communication in tissues, including adipose tissue. This review summarizes the action mechanisms of ncRNAs carried by exosomes on adipocyte differentiation and modulation of adipogenesis by exosomal ncRNAs. This study aims to provide valuable insights for developing novel therapeutics.

Efficacy and Safety of Conservative Treatment Compared With Surgical Treatment for Thoracolumbar Fracture With Score 4 Thoracolumbar Injury Classification and Severity (TLICS): A Systematic Review and Meta-analysis.

STUDY DESIGN: This was a systematic review and meta-analysis. OBJECTIVE: The clinical outcomes, radiologic outcome, and complications were compared between surgical treatment and conservative treatment of thoracolumbar fractures with a Thoracolumbar Injury Classification and Severity (TLICS) score of 4. SUMMARY OF BACKGROUND DATA: The thoracolumbar fracture is the main reason leading to the spinal cord injury. Some studies suggested that the treatment of TLICS=4 is a "gray zone." Hence, the efficacy and safety of surgical treatment and conservative treatment of thoracolumbar fractures with scores 4 TLICS was still debated. MATERIALS AND METHODS: A comprehensive search of PubMed, Embase, and the Cochrane Library, Chinese National Knowledge Infrastructure (CNKI), Chongqing VIP Database (VIP), and Wan Fang Database was performed up to October 2021. Relevant studies were identified using specific eligibility criteria and data was extracted and analyzed based on primary and secondary outcomes. RESULTS: A total of 10 studies involving 555 patients were included (3 randomized controlled trials and 7 retrospective studies). There was no significant difference of hospital time (standardized mean difference=0.24, 95% CI: -1.50 to 1.97, P=0.79) and Oswestry Disability Index (mean difference=2.97, 95% CI: -1.07 to 7.01, P=0.15) between surgery and nonsurgery. The length of returning to work was shorter in surgical treatment (standardized mean difference=1.27, 95% CI: 0.07-2.46, P=0.04). Visual Analog Scale in surgical treatment was lower at 1, 3, and 6 months (respectively, P<0.00001, P=0.003, and P=0.02). However, there existed no significant difference between surgical treatment and nonsurgical treatment at 12 and >24 months (respectively, P=0.18 and 0.17). Cobb angle was lower in surgical treatment at postoperative at 6, 12, and >24 months (respectively, P=0.005, P<0.00001, P=0.002, and P=0.0002). Finally, the surgical treatment had a lower incidence of complications (odds ratio=3.89, 95% CI: 1.90-7.94, P=0.0002). CONCLUSIONS: Current evidence recommended that surgical treatment is superior to conservative treatment of TLICS score of 4 at the early follow-up. Surgical treatment had lower Cobb angle, Visual Analog Scale scores, and complications compared with a nonsurgical TLICS score of 4. However, these findings needed to be verified further by multicenter, double-blind, and large-sample randomized controlled trials.

Efficacy and Safety of Lumbar Dynamic Stabilization Device Coflex for Lumbar Spinal Stenosis: A Systematic Review and Meta-analysis.

BACKGROUND: This systematic review and meta-analysis were performed to investigate evidence for the comparison of lumbar dynamic stabilization device Coflex (Surgalign, Deerfield, IL) with posterior lumbar fusion for lumbar spinal stenosis). METHODS: Relational databases were searched to October 2022. The main outcome measures included operation time, Japanese Orthopedic Association score (JOA), visual analog scale (VAS), Oswestry disability index (ODI), total complications, and adjacent segment degeneration (ASD). Statistical analysis was performed with Review Manager 5.3 (Cochrane Collaboration). RESULTS: A total of 26 studies were included. The main results of this meta-analysis showed lumbar dynamic stabilization device Coflex had shorter operation time (mean difference [MD] -50.77 min, 95% CI -57.24 to -44.30, P < 0.00001), less intraoperative blood loss (MD -122.21 mL, 95% CI -129.68 to -94.74, P < 0.00001), and shorter hospital stays (MD -3.21 days, 95% CI -4.04 to -2.37, P < 0.00001). What's more, the JOA score and ODI score were higher in the Coflex group during early follow-up. Yet, there was no significant difference between the 2 groups with the extension of follow-up time. Moreover, the Coflex group had a lower VAS score than fusion treatment (P < 0.00001). Finally, the Coflex group had lower total complications rate (P = 0.03), lower ASD rate (P = 0.001), and higher range of motion (P < 0.00001), but there was no significant difference in reoperation rate and internal fixation problems rate. CONCLUSIONS: Current evidence suggests that lumbar dynamic stabilization device Coflex is superior to posterior lumbar fusion in early follow-up. However, considering that the dynamic stabilization device group also has its limitations, these findings need to be further verified by multicenter, double-blind, and large-sample randomized controlled trials.

Platelet-rich plasma promotes peripheral nerve regeneration after sciatic nerve injury.

The effect of platelet-rich plasma on nerve regeneration remains controversial. In this study, we established a rabbit model of sciatic nerve small-gap defects with preserved epineurium and then filled the gaps with platelet-rich plasma. Twenty-eight rabbits were divided into the following groups (7 rabbits/group): model, low-concentration PRP (2.5-3.5-fold concentration of whole blood platelets), medium-concentration PRP (4.5-6.5-fold concentration of whole blood platelets), and high-concentration PRP (7.5-8.5-fold concentration of whole blood platelets). Electrophysiological and histomorphometrical assessments and proteomics analysis were used to evaluate regeneration of the sciatic nerve. Our results showed that platelet-rich plasma containing 4.5-6.5- and 7.5-8.5-fold concentrations of whole blood platelets promoted repair of sciatic nerve injury. Proteomics analysis was performed to investigate the possible mechanism by which platelet-rich plasma promoted nerve regeneration. Proteomics analysis showed that after sciatic nerve injury, platelet-rich plasma increased the expression of integrin subunit ß-8 (ITGB8), which participates in angiogenesis, and differentially expressed proteins were mainly enriched in focal adhesion pathways. Additionally, two key proteins, ribosomal protein S27a (RSP27a) and ubiquilin 1 (UBQLN1), which were selected after protein-protein interaction analysis, are involved in the regulation of ubiquitin levels in vivo. These data suggest that platelet-rich plasma promotes peripheral nerve regeneration after sciatic nerve injury by affecting angiogenesis and intracellular ubiquitin levels.