Treatment of Lumbar Degenerative Disease with a Novel Interlaminar Screw Elastic Spacer Technique: A Finite Element Analysis.

A novel interlaminar elastic screw spacer technique was designed to maintain lumbar mobility in treating lumbar degenerative diseases. A validated finite element model of L4/5 was used to establish an ISES-1/2 model and an ISES-1/3 model based on different insertion points, a unilateral fixation model and a bilateral fixed model based on different fixation methods, and a Coflex-F model based on different implants. The elastic rods were used to fix screws. Under the same mechanical conditions, we compared the biomechanical characteristics to investigate the optimal entry point for ISES technology, demonstrate the effectiveness of unilateral fixation, and validate the feasibility of the ISES technique. Compared to ISES-1/3, the ISES-1/2 model had lower intradiscal pressure, facet cartilage stress, and posterior structural stress. Compared to the ISES-BF model, the ISES-UF model had lower intervertebral pressure, larger mobility, and smaller stress on the posterior structures. The ISES model had a similar intervertebral pressure and limitation of extension as the Coflex-F model. The ISES model retained greater mobility and reduced the stress on the facet cartilage and posterior structure compared with the Coflex-F model. Our study suggests that the ISES technique is a promising treatment of lumbar degenerative diseases, especially those with osteoporosis.

Percutaneous robot-assisted screw fixation for nondisplaced pelvic fractures: a good choice?

PURPOSE: To compare the merits and demerits of percutaneous robot-assisted screw fixation for nondisplaced pelvic fractures with other treatments via long-term follow-up. METHODS: This was a retrospective analysis of nondisplaced pelvic fractures treated between January 2015 and December 2021. The number of fluoroscopy exposures, operative duration, intraoperative blood loss, surgical complications, screw placement accuracy and Majeed score were compared among the nonoperative group (24 cases), open reduction and internal fixation (ORIF) group (45 cases), free-hand empirical screw fixation (FH) group (10 cases) and robot-assisted screw fixation (RA) group (40 cases). RESULTS: There was less intraoperative blood loss in the RA and FH groups than in the ORIF group. The number of fluoroscopy exposures in the RA group was lower than that in the FH group but much higher than that in the ORIF group. There were five cases of wound infection in the ORIF group and no surgical complications in the FH or RA group. The medical expenses were higher in the RA group than in the FH group, with no significant difference from the ORIF group. The Majeed score was lowest in the nonoperative group three months after injury (64.5±12.0) but lowest in the ORIF group one year after injury (88.6±4.1). CONCLUSION: Percutaneous RA for nondisplaced pelvic fractures is effective and minimally invasive and does not increase medical expenses compared with ORIF. Therefore, it is the best choice for patients with nondisplaced pelvic fractures.

Robot-assisted vs traditional percutaneous freehand for the scaphoid fracture treatment: a retrospective study.

PURPOSE: The purpose of this study was to assess the efficiency, safety, and accuracy of cannulated screw fixation using a robot-assisted method compared with a traditional percutaneous freehand method. METHODS: This retrospective clinical study included 18 patients with scaphoid fracture who underwent cannulated screw fixation by robot-assisted technique or traditional percutaneous freehand technique from June 2018 to June 2020. All patients were divided into the robot-assisted group (9 patients) or the traditional surgery group (9 patients). The operation time, blood loss, number of intra-operative fluoroscopies, fracture healing time, Mayo wrist function score, and screw implantation accuracy were recorded in the two groups. RESULTS: The average age of the robot-assisted group was 37.9 ± 10.6 years (with a range of 30 to 52 years), there were eight males and one female, and there were six cases of scaphoid fracture on the right side and three on the left side. The average pre-operative time was 2.8 ± 0.7 days (ranging from 1 to 3 days). The average age of the traditional surgery group was 31.6 ± 6.8 years (with a range of 20 to 45 years), there were eight males and one female, and there were five cases of scaphoid fracture on the right side and four on the left side. The average pre-operative time was 2.1 ± 0.8 days (with a range of 2 to 4 days). The number of intra-operative fluoroscopies was 24.4 ± 3.5 in the traditional surgery group, whereas it was only 10.1 ± 1.9 in the robot-assisted group, which was significantly lower (P < 0.05). The average operation time of the traditional operation group was 48.4 ± 12.2 min, and that of the robot-assisted group was 32.6 ± 4.2 minutes, which was significantly shorter (P < 0.05). The angles between the actual screw position and the central axis of the scaphoid on both the coronal and sagittal post-operative CT images were 8.3° ± 2.3° and 8.8° ± 1.6° for the traditional operation group and 3.8° ± 0.8° and 4.3° ± 1.2° for the robot-assisted group, so the accuracy of the robot-assisted group was significantly higher (P < 0.05). There were no significant differences between the two groups in wrist function recovery or fracture healing time. CONCLUSION: Robot-assisted treatment of scaphoid fracture is more accurate than traditional freehand technology, with shorter operation time and fewer intra-operative fluoroscopies. There is no difference between the two surgical techniques in intra-operative bleeding, post-operative fracture healing, or functional recovery. Robot-assisted surgery is a safe, effective, and accurate method for treating scaphoid fracture.

Biomechanical evaluation of a short-rod technique for lumbar fixation surgery.

Objective: The purpose of this study was to analyze the stability and instrument-related complications associated with fixation of the lumbar spine using the Short-Rod (SR) technique. Methods: Using finite element analysis, this study assessed the stability of a bilateral lumbar fixation system when inserting the pedicle screws at angles of 10°, 15°, and 20° to the endplate in the sagittal plane. Using the most stable construct with a screw angle, the model was then assessed with different rod lengths of 25, 30, 35, and 45 mm. The optimal screw inclination angle and rod length were incorporated into the SR model and compared against traditional parallel screw insertion (pedicle screws in parallel to the endplate, PPS) in terms of the stability and risk of instrument-related complications. The following parameters were evaluated using the validated L4-L5 lumbar finite element model: axial stiffness, range of motion (ROM), stress on the endplate and facet joint, von-Mises stress on the contact surface between the screw and rod (CSSR), and screw displacement. Results: The results showed that the SR model with a 15° screw inclination angle and 35 mm rod length was superior in terms of construct stability and risk of complications. Compared to the PPS model, the SR model had lower stiffness, lower ROM, less screw displacement, and lower stress on the facet cartilage, the CSSR, and screws. However, the SR model also suffered more stress on the endplate in flexion and lateral bending. Conclusion: The SR technique with a 15° screw inclination and 35 mm rod length offers good lumbar stability with a low risk of instrument-related complications.

A systematic review and meta-analysis of elastic stockings for prevention of thrombosis after orthopedic surgery.

BACKGROUND: To investigate the preventive effect of elastic stockings on deep vein thrombosis (DVT) after orthopedic surgery by literature search and meta-analysis. METHODS: PubMed, Embase and Cochrane were selected as the search database platforms to search the literature of randomized controlled trials related to elastic stockings and DVT published from 2008 to date. Revman 5.3.5 software was used for statistical analysis of the data to obtain forest and funnel plots. RESULTS: In this study, 90 studies were initially screened and 7 were finally included, covering a total of 3,116 patients. Meta-analysis showed that the 7 studies had statistical heterogeneity (I2=32%, P=0.18), so a random effect model was used. The obtained statistic was [odds ratio (OR) =0.59, 95% confidence interval (CI): (0.34, 1.03)], the statistical effect size was Z=1.84, P=0.07, and the difference was not statistically significant, so a stepwise sensitivity analysis was performed by the exclusion method. One study was excluded, and the remaining 6 showed homogeneity (I2=0%, P=0.46). They were analyzed by subgroup according to the type of operation: ankle surgery or hip and knee arthroplasty. The internal literatures of each subgroup were homogeneous: ankle surgery subgroup (I2=0%, P=0.43), hip and knee arthroplasty subgroup (I2=0%, P=0.88). Therefore, fixed effect mode analysis was used, and the effect size of elastic stockings after ankle surgery was Z=3.65, P=0.0003, while the effect size of elastic stockings in the hip and knee arthroplasty subgroup was Z=1.23, P=0.22. DISCUSSION: Elastic stockings had an obvious preventive effect on DVT in patients undergoing ankle surgery, but not in patients undergoing lumbar, knee or spinal surgery. It is necessary to combine anticoagulant drugs and other physical therapies to prevent DVT.

Hydrogen sulfide inhibits calcium and phosphorus loss after fracture by negatively regulating glucocorticoid/glucocorticoid receptor α.

AIMS: Post-fracture calcium and phosphorus excretion is greater than influx, which might be caused by stress. Glucocorticoid is known to enhance calcium and phosphorous excretion, and hydrogen sulfide (H2S) has been shown to exert inhibitory effects on glucocorticoid. Therefore, this study explored whether H2S could inhibit calcium and phosphorus loss after fracture by regulating glucocorticoid and/or its receptor. MAIN METHODS: The following properties were analyzed in rats with femur fractures: serum and urinary calcium and phosphorus (by colorimetry); bone turnover markers alkaline phosphatase, serum type 1 collagen amino terminal peptide, type 1 procollagen carboxy terminal peptide, and anti-tartaric acid phosphatase (by ELISA); factors related to calcium-phosphorus metabolism including glucocorticoid, parathyroid hormone, calcitonin, fibroblast growth factor 23, and 1,25(OH)2D3 (by ELISA); and sulfhydration of glucocorticoid receptor α in the kidney (by immunoprecipitation linked biotin-switch assay), after supplementing with mifepristone, the H2S donor GYY4137 or H2S generating enzyme inhibitors aminooxyacetic acid and propargylglycine. KEY FINDINGS: Serum H2S decreased and glucocorticoid secretion increased in rats post-fracture. The glucocorticoid receptor inhibitor mifepristone partly blunted calcium and phosphorus loss. Furthermore, supplementation with GYY4137 reduced glucocorticoid secretion; inhibited glucocorticoid receptor α activity by sulfhydration; downregulated vitamin D 1α-hydroxylase expression; and upregulated 24-hydroxylase, calbindin-D28k, and sodium phosphate cotransporter 2a expression in the kidney; thereby inhibiting calcium and phosphorus loss induced by fracture. Moreover, inhibiting endogenous H2S generation showed opposite effects. SIGNIFICANCE: Our findings suggest that H2S antagonized calcium and phosphorus loss after fracture by reducing glucocorticoid secretion and inhibiting glucocorticoid receptor α activity by sulfhydration.

TiRobot-Assisted Percutaneous Cannulated Screw Fixation in the Treatment of Femoral Neck Fractures: A Minimum 2-Year Follow-up of 50 Patients.

OBJECTIVE: To assess the long-term clinical efficacy of TiRobot-assisted percutaneous cannulated screw fixation in the treatment of femoral neck fractures. METHODS: This retrospective study included 50 patients with unilateral femoral neck fractures who were treated with TiRobot-assisted percutaneous cannulated screw fixation from September 2017 to May 2018. After at least 2 years of follow-up, the results of treatment, including operation duration, frequency of fluoroscopy use, intraoperative bleeding, hospital stay, medical expense, screw placement accuracy, rate of fracture healing and necrosis of the femoral head, and Harris hip scores at the last follow up, were recorded and compared with those of 83 matched patients who underwent conventional manual positioning surgery. RESULTS: The TiRobot group had longer operation duration (83.3 ± 31.2 min vs 44.1 ± 14.8 min) and higher medical expenses (28,407.1 ± 7498.0 yuan vs 22,672.3 ± 4130.3 yuan) than the conventional group. The TiRobot group had significantly less intraoperative bleeding (11.3 ± 7.3 mL vs 51.6 ± 40.4 mL) and shorter hospital stay (8.6 ± 2.8 days vs 11.1 ± 3.41 days) than the conventional group. Screw parallelism (1.32° ± 1.85° vs 2.54° ± 2.99° on anteroposterior radiograph; 1.42° ± 2.25° vs 3.09° ± 3.63° on lateral radiograph) and distance between screws (58.44 ± 10.52 mm vs 39.69 ± 12.17 mm) were significantly improved. No significant difference was found between the two groups in terms of the use of fluoroscopy (40.1 ± 28.5 times vs 38.6 ± 21.0 times) and Harris hip scores at the last follow-up (93.2 ± 10.3 points vs 88.4 ± 11.9 points). Two cannulated screws penetrated the femoral head during manual insertion in the conventional group but not in the TiRobot group. The rate of nonunion and necrosis of the femoral head in the TiRobot group was reduced compared with that in the conventional group (0 vs 7.2%; 6.0% vs 24.1%). CONCLUSION: TiRobot-assisted percutaneous cannulated screw fixation of femoral neck fractures is accurate and minimally invasive and helps in reducing late complications, particularly necrosis of the femoral head and nonunion of fractures.

Involvement of circRNA_0007059 in the regulation of postmenopausal osteoporosis by promoting the microRNA-378/BMP-2 axis.

Increasing evidence suggests that postmenopausal osteoporosis (PMO), a severe disturbance, imposes heavy physical, psychosocial, and financial burdens and dramatically influences the quality of life of postmenopausal women. Circular RNAs (circRNAs) and microRNAs (miRs) play important roles in the occurrence and development of PMO. However, the roles of circRNAs and miRs in osteoporosis regulation still need to be further investigated. circRNAs with different expression levels in patients with PMO were screened via RNA-seq and bioinformatics analysis. We found that circ_0007059 was upregulated in patients with PMO and during osteoclastogenesis of human bone marrow stromal cells (hBMSCs). Next, we investigated the effect of circ_0007059 overexpression during osteoclastogenesis of hBMSCs. circ_0007059 overexpression attenuated hBMSC differentiation into osteoclasts in vitro. This was demonstrated by downregulated bone morphogenetic protein 2 (BMP-2) expression, upregulated osteoclast-specific gene expression, and TRAP staining. circ_0007059 was demonstrated to directly target miR-378, which in turn targeted BMP-2 via bioinformatics analysis and the dual-luciferase reporter assay. Transfection of the miR-378 mimic reversed the effect of circ_0007059 on the osteoclastogenesis of hBMSCs. These results suggest that circ_0007059 plays an important role in osteoclastogenesis via the miR-378/BMP-2 signaling pathway. Targeting the circ_0007059/miR-378/BMP-2 axis is possibly a novel idea in osteoporosis treatment.

Bone Morphogenetic Protein-2 Promotes Osteoclasts-mediated Osteolysis via Smad1 and p65 Signaling Pathways.

STUDY DESIGN: An in vitro biological study. OBJECTIVE: The aim of this study was to explore the role of bone morphogenetic protein-2 (BMP-2) in the regulation of osteoclast-mediated osteolysis, and the possible mechanism involving BMP-2 and nuclear factor-kappa B (NF-κB) signaling pathways. SUMMARY OF BACKGROUND DATA: Recombinant human BMP-2 (rhBMP-2) has been approved as a therapeutic agent in spinal fusion and bone defect repair. However, its efficacy and clinical application are limited by associated complications including osteoclast-mediated bone resorption. The mechanism of BMP-2-induced osteolysis remains unknown. METHODS: Bone marrow-derived macrophages (BMMs) were isolated from C57BL/6J mice and cultured with macrophage colony-stimulating factor (M-CSF) and receptor activator for nuclear factor-κB Ligand (RANKL) to induce osteoclast differentiation. An in vitro bone resorption assay was performed by co-culturing BMMs and bone slides. The expression of BMP canonical and NF-κB signaling factors and their interaction during signal transduction were quantitated by reverse transcription polymerase chain reaction, Western blot analysis, confocal microscopy, and co-immunoprecipitation. RESULTS: BMP-2 enhanced osteoclast-mediated bone resorption via inducing osteoclast differentiation in a concentration-dependent manner. In addition, a high concentration of BMP-2 significant upregulated phosphorylation of BMP signaling factors p-Smad1/5/8 and NF-κB downstream factor p65, and promoted the degeneration of IκBα. In addition, BMP-2 induced osteoclast differentiation through coupling between BMP receptor II and RANK. CONCLUSION: High concentrations of BMP-2 enhanced osteoclast-mediated bone resorption by promoting RANKL-induced pre-osteoclast differentiation, probably by mediating the cross-talk between BMP canonical and NF-κB signaling pathways.Level of Evidence: N/A.

Perioperative Coagulation Profile with Thromboelastography in Aspirin-Treated Patients Undergoing Posterior Lumbar Fusion.

BACKGROUND: It has been generally recommended that platelet function may recover after the recommended 5-day discontinuation period prior to operation. The technique of thromboelastography has been demonstrated to monitor intraoperative platelet function in liver transplantation and coronary bypass surgery. However, there is a dearth of literature that addresses the utility of thromboelastography in aspirin-treated patients undergoing fusion. OBJECTIVES: To introduce a functional method of monitoring coagulation and validate the effectiveness of thromboelastography perioperatively in assessing aspirin-treated patients undergoing posterior lumbar fusion. STUDY DESIGN: This research used a retrospective study design. SETTING: Orthopedic Department of Changhai Hospital,Shanghai, China and Orthopedic and Anesthesia Department of Changzheng Hospital. METHODS: Eighty patients were divided into aspirin-naive and aspirin-treated groups in this study. They had equally undergone lumbar fusion surgery for at least one or more segments between January and June 2018. They matched for age, gender, number of fused segments, and surgical procedures. The coagulation profile, including the reaction time (R), kinetics (K), maximal amplitude (MA), alpha-angle, and coagulation index (CI), platelet inhibition ratio (PIR) was analyzed by thromboelastogram (TEG) prior to operation and on preoperative days 1, 3, and 5. Correlation analysis included parameters such as waiting time, intraoperative blood loss, and postoperative drainage. RESULTS: Perioperatively, the TEG values including R, K, MA, alpha-angle, and CI, PIR, and correlation analysis showed no significant difference between the 2 groups, respectively (P > 0.05). LIMITATIONS: First, the relatively small number of patients recruited limits control over other factors; larger studies may need to confirm our findings. Second, the patients were objectively less healthy with more medication treatment, which may result in a variance in the amount of blood loss. Randomized controlled studies are needed to further confirm these results. CONCLUSIONS: TEG may be a helpful method to monitor perioperative platelet function in aspirin-treated patients undergoing fusion. It may be comparatively safe to relax the restriction of the aspirin-discontinued therapeutic window to approximately 2 to 3 days prior to surgery.

Effect of changes in serum levels of endogenous hydrogen sulfide on fracture healing: Study protocol clinical trial (SPIRIT compliant).

BACKGROUND: Fracture is a common disease; many factors affect fracture healing. Recent studies have confirmed that hydrogen sulfide (H2S) plays an essential role in bone formation, but most of these studies are drawing conclusions based on animal experiment; whether H2S could promote fracture healing in patients is still unclear. We aim to investigate the change of serum H2S in fracture patients, and analyze its effort on fracture healing. METHODS: This is a single-center, prospective cohort study. Patients with spinal or limb fracture will be recruited. Patient's serum and urine will be collected at baseline for examination (serum H2S, ß-CTX, OC, PINP, 25-OH-VitD3, S-CTX, urinary calcium, and urinary creatinine). All patients will be followed-up for 24 months in outpatients settings, the image of X-ray or CT will be reviewed and fracture healing will be judged by 2 experienced orthopedic physicians. The difference in serum parameters especially H2S will be compared between patients with fracture healed within 9 months and those with fracture unhealed at 9 months. DISCUSSION: Results of the trial could provide insight into influence of H2S on fracture healing. ETHICS AND DISSEMINATION: The study was approved by the ethics committee of School of Medicine UESTC & Sichuan Provincial People's Hospital Ethics Committee. All the participants will be asked to provide written informed consent before data collection. The findings of the study will be published in peer-reviewed journals and will be presented at national or international conferences.

Quantum walks on regular uniform hypergraphs.

Quantum walks on graphs have shown prioritized benefits and applications in wide areas. In some scenarios, however, it may be more natural and accurate to mandate high-order relationships for hypergraphs, due to the density of information stored inherently. Therefore, we can explore the potential of quantum walks on hypergraphs. In this paper, by presenting the one-to-one correspondence between regular uniform hypergraphs and bipartite graphs, we construct a model for quantum walks on bipartite graphs of regular uniform hypergraphs with Szegedy's quantum walks, which gives rise to a quadratic speed-up. Furthermore, we deliver spectral properties of the transition matrix, given that the cardinalities of the two disjoint sets are different in the bipartite graph. Our model provides the foundation for building quantum algorithms on the strength of quantum walks on hypergraphs, such as quantum walks search, quantized Google's PageRank, and quantum machine learning.

Controlled Alternate Quantum Walks based Quantum Hash Function.

Through introducing controlled alternate quantum walks, we present controlled alternate quantum walks (CAQW) based quantum hash function. CAQW based quantum hash function have excellent security, outstanding statistical performance and splendid expansibility. Furthermore, due to the structure of alternate quantum walks, implementing CAQW based quantum hash function significantly reduces the resources necessary for its feasible experimental realization than implementing other quantum hash functions.

Age-Related Insulin-Like Growth Factor Binding Protein-4 Overexpression Inhibits Osteogenic Differentiation of Rat Mesenchymal Stem Cells.

BACKGROUND/AIMS: Insulin-like growth factor binding proteins (IGFBP) play important roles in bone metabolism. IGFBP4 is involved in senescent-associated phenomena in mesenchymal stem cells (MSCs). The goal of the present study was to determine whether age-related IGFBP4 overexpression is associated with the impaired osteogenic differentiation potential of aged bone marrow derived MSCs. METHODS: MSCs were isolated from Sprague-Dawley rats aged 3-26 months. The bone morphogenetic protein (BMP)-2-induced osteogenic differentiation of rat MSCs was assessed by analyzing the expression levels of osteoblast marker genes [runt-related transcription factor 2 (RUNX2), alkaline phosphatase (ALP), and osteocalcin (OC)], ALP activity and calcification. RESULTS: Our study showed that IGFBP4 mRNA and protein expression increased with age in parallel with impaired osteogenic differentiation of MSCs cultured in BMP2-containing osteogenic medium, as evidenced by the downregulation of osteoblast marker genes, and decreased ALP activity and calcium deposits. IGFBP4 overexpression impaired BMP2-induced osteogenic differentiation potential of young MSCs, whereas IGFBP4 knockdown restored the osteogenic potency of aged MSCs. Moreover, IGFBP4 knockdown stimulated the activation of Erk and Smad by increasing phosphorylation. CONCLUSION: Collectively, our results demonstrate that IGFBP4 overexpression plays a role in the impairment of MSC differentiation potential via the Erk and Smad pathways, suggesting potential targets to improve MSC function for cell therapy applications.

Celastrol inhibits chondrosarcoma proliferation, migration and invasion through suppression CIP2A/c-MYC signaling pathway.

Chondrosarcomas (CS) is the second most frequent tumors of cartilage origin. A small compound extracted from Thunder God Vine (Tripterygium wilfordii Hook. F.) called celastrol can directly bound CIP2A protein and effectively inhibit cell proliferation and induce apoptosis in several cancer cells. However, little knowledge is concern about the important role of CIP2A in CS patients and the therapeutic value of celastrol on CS. Our results showed that CIP2A and c-MYC were verified to be oncoproteins by detecting their mRNA and protein expression in 10 human CS tissues by qRT-PCR and Western blots. After treatment of celastrol, the proliferation, migration and invasion were significantly inhibited; whereas the apoptosis was largely induced in human CS cell lines. In addition, celastrol inhibited the expression of CIP2A, c-MYC, and suppressed apoptotic proteins BAX and caspase-8 in human CS cells, on the other hand, it induced the expression of antiapoptotic protein Bcl-2. Finally, knockdown of CIP2A also inhibited the migration and invasion and induced apoptosis of human CS cells. To sum up, we found that celastrol had effects on inhibiting proliferation, migration, invasion and inducing apoptosis through suppression CIP2A/c-MYC signaling pathway in vitro, which may provide a new therapeutic regimen for CS.

[Treatment of sternoclavicular joint dislocation with sternoclavicular hook plate fixation].

OBJECTIVE: To evaluate the technique and therapeutic effect of sternoclavicular hook plate fixation in treating sternoclavicular joint (SCJ) dislocation. METHODS: From January 2010 to March 2014,6 patients with SCJ dislocation were treated with sternoclavicular hook plate fixation in our hospital. Among the 6 patients, 5 patients were male and 1 patient was female, and the average age was 34 years, ranging from 26 to 48 years. The course of the disease ranged from 3 to 20 days. All the SCJ dislocations were caused by external injury and accompanied with the symptoms of swelling pain and obvious shoulder joint activity restricted in affected side. All SCJ dislocations were anterior dislocation by the diagnosis of X-ray and CT scan. The postoperative curative effect was evaluated according to Rockwood score. RESULTS: All the patients' operative incision were healed well and in good appearance. X-ray showed that the dislocated SCJ was well reduced and the plate was on right position. All the 6 patients were followed up for 4 to 18 months, with an average of 12 months. The results were evaluated according to Rockwood score, 4 got excellent results, 1 good and 1 fair. No fixation loosening, redislocation or side injury such as vessel, nerve or pleura injury were found. CONCLUSION: With sternoclavicular hook plate fixation, SCJ dislocation could be reduced while keeping its amphiarthrodial function and the completeness of the cartilage surface. Sternoclavicular hook plate fixation has advantages of safety and stabilization in fixation, and patients can begin function exercises earlier.

Atomic resolution tomography reconstruction of tilt series based on a GPU accelerated hybrid input-output algorithm using polar Fourier transform.

Advances in diffraction and transmission electron microscopy (TEM) have greatly improved the prospect of three-dimensional (3D) structure reconstruction from two-dimensional (2D) images or diffraction patterns recorded in a tilt series at atomic resolution. Here, we report a new graphics processing unit (GPU) accelerated iterative transformation algorithm (ITA) based on polar fast Fourier transform for reconstructing 3D structure from 2D diffraction patterns. The algorithm also applies to image tilt series by calculating diffraction patterns from the recorded images using the projection-slice theorem. A gold icosahedral nanoparticle of 309 atoms is used as the model to test the feasibility, performance and robustness of the developed algorithm using simulations. Atomic resolution in 3D is achieved for the 309 atoms Au nanoparticle using 75 diffraction patterns covering 150° rotation. The capability demonstrated here provides an opportunity to uncover the 3D structure of small objects of nanometers in size by electron diffraction.

[Case-control study on hidden blood loss in perioperative period of femoral intertrochanteric fractures in elderly patients treated with intramedullary nailing].

OBJECTIVE: To analyze the neglected hidden blood loss before and after operations in the elderly patients with intertrochanteric fractures and strengthen the treatment and clinical nursing in the perioperative period in order to ensure clinical effects. METHODS: The clinical data of 99 patients with intertrochanteric fracture treated with intramedullary nailing from January 2010 to January 2014 were retrospectively analyzed (47 males and 52 females). Forty-seven cases got blood transfusion supporting and 52 cases were not (blood transfusion group and no-blood transfusion group respectively). According to the Gross equation, the average hemoglobin (Hb) and hematocrit (HCT) were used to analyze blood loss in perioperative period and assess the patients' hidden blood loss situation. RESULTS: There were 22 males and 30 females in blood transfusion group. The average operative time was (62.13±4.01) min; intraoperative visible blood loss and postoperative drainage were 215 ml, totally; preoperative Hb was (103.22±9.01) g/L and postoperative was (81.13±6.20) g/L; preoperative HCT was (96.93±3.38) I/L and postoperative was (308.00±11.81) I/L. There were 25 males and 22 females in no-blood transfusion group. The average operative time was (60.12±3.27) min; intraoperative visible blood loss and postoperative drainage were 196 ml, totally; the average blood transfusion were 621 ml; preoperative Hb was (92.15±5.46) g/L and preoperative was (95.20±8.93) g/L; preoperative HCT was (96.52±3.63) I/L and preoperative was (392.70±14.03) I/L. According to the Gross equation, the blood loss of no-blood transfusion group and blood transfusion group in peroperative period were (937.29±63.04) ml and (706.43±35.02) ml, respectively. The hidden blood loss was dominant. At 1, 3 months after operation, Harris score of blood transfusion group was better than that of no-blood transfusion group, and 12 months after operation, there was no significant difference between two groups. CONCLUSION: The hidden blood loss of intramedullary nailing for intertrochanteric fracture should be emphasized in perioperative period, it can avoid the perioperative complications caused by anemia and affect the prognosis of patients.

[One-stage operation for pelvis and acetabular fractures combined with Morel-Lavallée injury by internal fixation associated with vacuum sealing drainage].

OBJECTIVE: To investigate the methods and effectiveness of one-stage operation for pelvis and acetabular fractures combined with Morel-Lavallée injury by internal fixation associated with vacuum sealing drainage (VSD). METHODS: Between June 2008 and October 2012, 15 cases of pelvis and acetabular fractures combined with Morel-Lavallée injury were treated. There were 5 males and 10 females, aged from 18 to 67 years (mean, 36.8 years). Fractures were caused by traffic accident in 11 cases and crashing injury of heavy object in 4 cases. The time from injury to hospitalization was 3 hours to 9 days (mean, 5.4 days). Morel-Lavallée injury located in the above posterior superior iliac spine in 4 cases, greater trochanter in 7 cases, and anterior proximal thigh in 4 cases. In 10 cases complicated by pelvic fracture, there were 1 case of anteroposterior compression type, 3 cases of lateral compression type, 5 cases of vertical shear type, and 1 case of compound injury type; in 5 cases complicated by acetabular fracture, there were 1 case of transverse fracture, 1 case of posterior wall and posterior column fracture, 1 case of transverse acetabulum plus posterior wall fracture, and 2 cases of both columns fracture. Open reduction and internal fixation were used to treat pelvic and acetabular fractures, and VSD to treat Morel-Lavallée injury. When the drainage volume was less than 20 mL/d, interrupted wound suture or free skin grafting was performed. RESULTS: The hospitalization time was 16-31 days (mean, 20.8 days). Thirteen cases were followed up 4-16 months (mean, 7.8 months). The healing time of Morel-Lavallée injury was 16-36 days after operation (mean, 21.3 days). All the wounds had primary healing, and no infection occurred. The X-ray films showed that all fractures healed, with a mean healing time of 13.6 weeks (range, 11-18 weeks). At 6.5 months after operation, according to Majeed function scoring system in 8 cases of pelvic fracture, the results were excellent in 5 cases, good in 2 cases, and fair in 1 case; according to Harris hip scoring in 4 cases of acetabular fracture, the results were excellent in 2 cases, good in 1 case, and fair in 1 case. CONCLUSION: To pelvis-acetabular fractures combined with Morel-Lavallée injury, internal fixation treatment for fracture and VSD for Morel-Lavallée injury not only can cure merge Morel-Lavallée injury effectively, but also can guarantee the operation timing and incision safty of the pelvis-acetabular fractures.