The prevalence of soft tissue injuries in operative Schatzker type IV tibial plateau fractures.

BACKGROUND: To describe the incidence of soft-tissue injuries in patients with surgically treated Schatzker type IV tibial plateau fractures. METHODS: All tibial plateau fractures in skeletally mature patients treated operatively between January 2013 and August 2018 were retrospectively reviewed using a clinical medical record system. All fractures were categorized according to the AO/OTA classifications. Twenty-seven patients with Schatzker type IV tibial plateau fractures were further classified based on the Wahlquist classification. Associated soft-tissue injuries, which consisted of cruciate ligament injuries, and meniscal and collateral ligament injuries, were diagnosed through operation notes and magnetic resonance imaging (MRI) data. The categorical variables were tested by the chi-square test or Fisher's exact test. RESULTS: The incidence of lateral meniscus tears and medial meniscus tears was 63% and 44.4% in Schatzker type IV tibial plateau fractures, respectively. Twenty-five (92.6%) patients had sustained anterior cruciate ligament (ACL) injuries, and 19 (70.4%) patients had an incomplete injury of the posterior cruciate ligament (PCL). There were 17 (63%) lateral collateral ligament (LCL) injuries, and 8 (29.6%) medial collateral ligament (MCL) injuries. Using the Wahlquist classification, these fractures were categorized as follows: type A, one patient; type B, six patients; type C, twenty patients. There was no significant difference between the type of fracture and the location of soft tissue injuries. CONCLUSIONS: This study found that operative Schatzker type IV tibial plateau fractures represented a high incidence of soft-tissue injuries, especially LCL injuries, ACL injuries, and meniscus tears. Based on our data, we believe that soft-tissue injuries in operative Schatzker type IV tibial plateau fractures deserve more attention.

Influence of distal radius fractures involving the intermediate column on forearm rotation.

BACKGROUND: The objective of the study was to compare the radiologic and clinical outcome of patients with distal radius fractures involving the intermediate column and distal radial metaphyseal fractures treated conservatively. METHODS: Two cohorts of 52 matched patients with distal radius fractures treated conservatively, one with a fracture involving the intermediate column and the other with no intermediate column fracture, were retrospectively analyzed by examining the data. Patients were matched for age, sex, fracture side, and AO fracture type. The two groups were analyzed for differences in wrist motion; grip strength; Gartland and Werley score; Disabilities of the Arm, Shoulder and Hand (DASH) score; and visual analogue scale (VAS) score at 12 months. The differences in continuous variables were compared using the paired t test. Linear regression analyses or Pearson correlation analyses were used to evaluate the associations of radiological parameters with clinical outcomes. RESULTS: The analysis showed significant differences in the range of motion (ROM) for pronation (p = 0.000) and supination (p = 0.008) in the paired groups. There was a significant difference in DASH scores (p = 0.024) in the paired groups. Using Pearson correlation analysis, negative correlations (r = - 0.360, p = 0.000) were observed between articular step-off and ROM for pronation. Linear regression analyses also indicated that ROM for pronation had negative relationships (ß = - 6.327, p = 0.001) with articular step-off. CONCLUSIONS: Distal radius fractures involving the intermediate column had an adverse effect on forearm rotation after distal radius fractures treated conservatively.

[Effectiveness analysis of surgical treatment of Schatzker type â £ tibial plateau fractures].

Objective: To introduce a surgical protocol based on the location and orientation of the apex of the medial condylar fracture line for the treatment of Schatzker type Ⅳ tibial plateau fractures and report the preliminary effectiveness. Methods: The clinical data of 18 patients with Schatzker type Ⅳ tibial plateau fractures underwent open reduction and internal fixation between March 2012 and April 2016 were retrospectively analysed. There were 6 males and 12 females, aged 36-74 years (mean, 45 years). The causes of injury included traffic accident in 2 cases, falling in 14 cases, bruise injury in 1 case, and crush injury of heavy object in 1 case. All cases were fresh closed fractures, without injury of nerves and blood vessels. According to sub type of Wahlquist tibial plateau type Ⅳ fracture classification, there were 1 case of type A, 5 cases of type B, and 12 cases of type C. The interval of injury and operation was 6-16 days (mean, 9.5 days). The location of the apex of the medial condylar fracture line was determined the surgical approach. After operation, reduction of tibial plateau fractures was evaluated by the DeCoster score evaluation criteria. The knee joint function was assessed by short Musculoskeletal Function Assessment (SMFA) score and Hospital for Special Surgery (HSS) score. Results: The incisions all healed by first intension after operation without surgery related complications. All the patients obtained satisfactory exposure and reduction during operation. According to DeCoster score evaluation criteria, the results were excellent in 13 cases and fair in 5 cases. All the patients were followed up 12-30 months (mean, 18 months). X-ray films showed that all fractures healed at 10-16 weeks (mean, 12 weeks) after operation. There was no plate displacement, screw loosening, and other complications occurred during follow-up. At last follow-up, the SMFA score was 15-48 (mean, 28.5). The HSS score was 52-94 (mean, 81.1), and the results were excellent in 10 cases, good in 5 cases, fair in 2 cases, and poor in 1 case with an excellent and good rate of 83.3%; the main clinical manifestation was severe traumatic osteoarthritis symptom in 1 case with the fair result. Conclusion: The surgical program should be developed based on the location and orientation of the apex of the medial condylar fracture line. Open reduction and internal fixation for treating Schatzker type Ⅳ fractures can achieve satisfactory effectiveness.

Construction of Radial Defect Models in Rabbits to Determine the Critical Size Defects.

Many studies aimed at investigating bone repair have been conducted through animal models in recent years. However, limitations do exist in these models due to varying regeneration potential among different animal species. Even using the same animal, big differences exist in the size of critical size defects (CSD) involving the same region. This study aimed to investigate the standardization of radial bone defect models in rabbits and further establish more reliable CSD data. A total of 40 6-month-old New Zealand white rabbits of clean grade totaling 80 radial bones were prepared for bone defect models, according to the principle of randomization. Five different sizes (1.0, 1.2, 1.4, 1.7 and 2.0 cm) of complete periosteal defects were introduced under anesthesia. At 12 weeks postoperatively, with the gradual increase in defect size, the grades of bone growth were significantly decreased in all 5 groups. X-ray, CT scans and H&E staining of the 1.4, 1.7, and 2.0-cm groups showed lower grades of bone growth than that of the 1.0 and 1.2-cm groups respectively (P < 0.05). Using rabbit radial defect model involving 6-month-old healthy New Zealand white rabbits, this study indicates that in order to be critical sized, defects must be greater than 1.4 cm.

Identification of genes associated with osteoarthritis by microarray analysis.

The aim of the present study was to investigate the mechanisms of osteoarthritis (OA). Raw microarray data (GSE51588) were downloaded from Gene Expression Omnibus, including samples from OA (n=20) and non­OA (n=5) knee lateral and medial tibial plateaus. Differentially expressed genes (DEGs) were identified using Student's t­test. Functional and pathway enrichment analyses were performed for the upregulated and downregulated DEGs. A protein­protein interaction network (PPI) was constructed according to the Search Tool for the Retrieval of Interacting Genes/Proteins database, and module analysis of the PPI network was performed using CFinder. The protein domain enrichment analysis for genes in modules was performed using the INTERPRO database. A total of 869 upregulated and 508 downregulated DEGs were identified. The enriched pathways of downregulated and upregulated DEGs were predominantly associated with the cell cycle (BUB1, BUB1B, CCNA2, CCNB1 and CCNE1), and extracellular matrix (ECM)­receptor interaction (CD36, COL11A2, COL1A1, COL2A1 and COL3A1). Functional enrichment analysis of the DEGs demonstrated that FGF19, KIF11 and KIF2C were involved in the response to stress and that ACAN, ADAMTS10 and BGN were associated with proteinaceous ECM. The top protein domain was IPR001752: Kinesin motor region involving three genes (KIF2C, KIF11 and KIF20A). The identified DEGs, including KIF2C, KIF11 and KIF20A, may be significant in the pathogenesis of OA.

Inhibitory effects of platelet-rich plasma on intervertebral disc degeneration: a preclinical study in a rabbit model.

BACKGROUND: Platelet-rich plasma (PRP) contains multiple growth hormones that may stimulate tissue repair. This study aimed to assess the effects of PRP in a rabbit model of IDD (annulus fibrosus puncture). MATERIAL/METHODS: Thirty-six adult New Zealand white rabbits were randomly divided into 3 groups: 0.1 mL PRP (group A), 0.1 mL phosphate-buffered saline (group B), and control (group C) (n=12/group). Annulus fibrosus puncture was performed to establish L4/5 and L5/6 IDD models. Two and 4 weeks later, 6 rabbits from each group were given an IVD injection at L4/5 and L5/6. Two or 4 weeks after injection, rabbits were scanned with X-ray and MRI before being sacrificed. IVDs were collected for hematoxylin and eosin, Masson's trichrome, and Safranin O staining, and type II collagen immunohistochemistry. RESULTS: Over time, IVD height and disc imaging signal intensity decreased gradually in groups B and C, but only slightly in group A (baseline: 100% for all groups; A: 95.9±4.2% at 4 weeks, 90.1±8.4 at 6 weeks; B: 75.3±5.7% at 4 weeks, 70.8±6.4% at 6 weeks; C: 74.7±5.5% at 4 weeks, 69.9±6.2% at 6 weeks; all P<0.001, P<0.01 between A vs. B and C). Degenerative histological changes in IVDs in groups B and C were more severe compared with group A. CONCLUSIONS: Platelet-rich plasma interventions can effectively attenuate the IDD process in rabbits.

Wogonin protects rat dorsal root ganglion neurons against tunicamycin-induced ER stress through the PERK-eIF2α-ATF4 signaling pathway.

Endoplasmic reticulum (ER) stress has been demonstrated to contribute to neurodegeneration in multiple nervous system diseases. Wogonin is a flavonoid isolated from Scutellaria baicalensis root and has multiple pharmacological effects, including anti-inflammatory, antioxidant, and anticancer effects. It has a protective role in nervous system diseases; however, the pharmacological function of wogonin in the spinal cord is still with limited acquaintance. In the present study, rat dorsal root ganglion (DRG) neurons were pretreated with different concentrations of wogonin (0-100 µM) before inducing ER stress using tunicamycin (TUN) (0.75 µg/ml). Wogonin pretreatment at 75 and 100 µM had a cytoprotective effect on cells against TUN-induced toxicity. Wogonin also decreased the number of the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-positive DRG neurons and increased expression of superoxide dismutase (SOD), which was accompanied by decreased malondialdehyde (MDA) level. The induction of apoptosis was prevented with reduction in expression level of Bax and concomitant increase in B cell lymphoma 2 (Bcl-2) level. Furthermore, wogonin downregulated expression level of ER stress genes coding for glucose-regulated protein 78 (GRP78), C/EBP homologous protein (CHOP), active caspase 12, transcription factor 4 (ATF4), and phosphorylation of pancreatic ER stress kinase (PERK) and eukaryotic initiation factor 2 alpha (eIF2α). The current study indicated that wogonin modulated stress-responsive genes, helping DRG neurons prevent TUN-induced ER stress through the PERK-eIF2α-ATF4 signaling pathway.

The downregulation of miR-144 is associated with the growth and invasion of osteosarcoma cells through the regulation of TAGLN expression.

Alterations in the expression of microRNAs (miRNAs or miRS) have been implicated in the pathogenesis of the majority of human malignancies, and the dysregulation of microRNA-144 (miR-144) has been associated with several diseases. However, the potential involvement of miR-144 in osteosarcoma, a common malignant bone tumor in children and adolescents with a high risk of relapse and metastasis, has not yet been fully investigated. In the present study, we examined the expression and roles of miRNAs in osteosarcoma as potential diagnostic markers and therapeutic targets, and we focused on miR-144 due to its known involvement in osteogenesis. We demonstrate that miR-144 is downregulated in osteosarcoma cell lines and primary human osteosarcoma tissue samples and that its ectopic expression inhibits osteosarcoma cell proliferation and invasion. We identified TAGLN as a downstream target of miR-144 and demonstrated that its expression is upregulated in osteosarcoma cell lines and tumor tissue and is inversely correlated with miR-144 expression. Our results indicate that miR-144 may regulate osteosarcoma cell proliferation and invasion by downregulating its target gene, TAGLN, suggesting that miR-144 may be a potential therapeutic target for the treatment of osteosarcoma.

Repair of bone defect with vascularized tissue engineered bone graft seeded with mesenchymal stem cells in rabbits.

This study evaluated the results of repair of the radius defect with a vascularized tissue engineered bone graft composed by implanting mesenchymal stem cells (MSCs) and a vascular bundle into the xenogeneic deproteinized cancellous bone (XDCB) scaffold in a rabbit model. Sixty-four rabbits were used in the study. Among them, four rabbits were used as the MSCs donor. Other 57 rabbits were divided into five groups. In group one (n = 9), a 1.5 cm bone defect was created with no repair. In group two (n = 12), the bone defect was repaired by a XDCB graft alone. In group three (n = 12), the defect was repaired by a XDCB graft that included a vascular bundle. In group four (n = 12), the defect was repaired by a XDCB graft seeded with MSCs. In group five (n = 12), the defect was repaired by a XDCB graft including a vascular bundle and MSCs implantation. The rest three rabbits were used as the normal control for the biomechanical test. The results of X-ray and histology at postoperative intervals (4, 8, and 12 weeks) and biomechanical examinations at 12 weeks showed that combining MSCs and a vascular bundle implantation resulted in promoting vascularization and osteogenesis in the XDCB graft, and improving new bone formation and mechanical property in repair of radius defect with this tissue engineered bone graft. These findings suggested that the vascularized tissue engineered bone graft may be a valuable alternative for repair of large bone defect and deserves further investigations.