Diagnostic value of curved planar reformation of MRI for lumbosacral nerve roots in the localization of nerve roots for adult lumbar degenerative scoliosis.

PURPOSE: To compare the diagnostic value of curved planar reformation of MRI (MRI-CPR) and 2D MRI in determining the responsible nerve in patients with adult lumbar degenerative scoliosis (ALDS). METHOD: A total of 45 patients diagnosed with ALDS were included in the study. All patients underwent MRI-CPR and 2D MRI and subsequently received surgery. These two diagnostic methods were compared with the results of surgical exploration to assess nerve root compression. RESULTS: The sensitivity and accuracy of MRI-CPR are higher than 2D MRI (93.8% vs 80.0%; 92.8% vs 77.7%, respectively). And the specificity of MRI-CPR is higher than 2D MRI (87.5% vs 68.8%). Besides, the PPV and NPV of MRI-CPR are higher than 2D MRI (96.8% vs 91.2%; 7.8.% vs 45.8%). The area (AUC) under the receiver operating characteristic curve (ROC) for MRI-CPR and 2D MRI was 0.74 and 0.91, respectively. The judgement was made by two independent radiologists, while the consistency tests for 2D MRI and MRI-CPR with Kappa values were 90.6% and 82.2%, respectively. CONCLUSIONS: The clinical diagnostic value of MRI-CPR was better than 2D MRI in the determination of the responsible nerve root. Moreover, MRI-CPR sequence images can clearly show the route of lumbosacral nerve roots and their relationship with adjacent tissues. Therefore, MRI-CPR can be an important complement to conventional 2D MRI in the diagnosis of responsible nerve roots in patients with ALDS.

Immune-based prognostic biomarkers associated with metastasis of osteosarcoma.

This study aimed to identify immune-based prognostic biomarkers associated with metastasis of osteosarcoma. Based on the GEO and TCGA databases, 437 differentially expressed genes were screened between primary and metastatic osteosarcoma. Weighted gene co-expression network analysis (WGCNA) revealed 496 genes in turquoise module which had the highest correlation with osteosarcoma metastasis. Within these two group genes, 122 common genes involved in osteosarcoma metastasis were identified. These genes were enriched in chemokine activity, chemokine receptor binding, TNF signaling pathway, etc. Survival analysis revealed 8 prognostic genes (ANK3, EGR1, FBP1, FOS, KIFC3, MAOB, ISLR and MFAP4) from the 122 genes. RT-qPCR showed that all of these eight genes were differentially expressed between 143B and MNNG/HOS Cl cells. Various infiltrating immune cells showed significant differences between primary and metastatic osteosarcoma. Expression of all the 8 prognostic genes was correlated with infiltration abundance of multiple immune cells, such as follicular helper T cells, activated dendritic cells. In addition, 10 microRNAs and 7 transcription factors that targeted these prognostic genes were predicted. In conclusion, 8 immune-based prognostic genes associated with osteosarcoma metastasis were identified.

Osteostatin improves the Osteogenic differentiation of mesenchymal stem cells and enhances angiogenesis through HIF-1α under hypoxia conditions in vitro.

BACKGROUND: Hypoxia conditions induced by bone defects would prolong the duration of bone regeneration. The effect of osteostatin (OST) on the osteogenic differentiation of mesenchymal stem cells (MSCs) and angiogenesis under hypoxia conditions remain unexplored. METHODS: SPF mice were obtained, and MSCs were isolated from bone marrow. MSCs were treated with 1% oxygen for hypoxia induction, and 200 nM of OST was used to treat cells under nomorxia or hypoxia conditions. Cell proliferation was evaluated using CCK8 assay, and trypan blue staining was implemented for determining cell death ratio. Alkaline phosphatase activity and alizarin redS staining was conducted to histologically evaluated osteogenic differentiation. Flow cytometry was used for the detection of CD31hiEmcnhi cells (Type H ECs), whose migration was detected by Transwell assay and angiogenesis was measured by tube formation assay. Protein level was measured by western blotting and mRNA level was monitored via RT-qPCR. RESULTS: The MSC proliferation was enhanced by OST under hypoxia conditions. The osteogenic differentiation of MSCs was decreased under hypoxia conditions, and treatment of OST significantly reversed its inhibitory effect. The hypoxia treated culture medium of MSCs promoted the proliferation, migration, and angiogenesis of type H ECs, while the effects were further strengthened by OST addition. HIF-1α was found to be upregulated in hypoxia treated MSCs, whereas silencing of HIF-1α had reversed effects on the angiogenic capacity of Type H ECs. CONCLUSION: OST improved the proliferation and osteogenic differentiation of MSCs and further promoted angiogenesis of type H ECs through upregulating HIF-1α expression.

Study on Multi-GNSS Precise Point Positioning Performance with Adverse Effects of Satellite Signals on Android Smartphone.

The emergence of dual frequency global navigation satellite system (GNSS) chip actively promotes the progress of precise point positioning (PPP) technology in Android smartphones. However, some characteristics of GNSS signals on current smartphones still adversely affect the positioning accuracy of multi-GNSS PPP. In order to reduce the adverse effects on positioning, this paper takes Huawei Mate30 as the experimental object and presents the analysis of multi-GNSS observations from the aspects of carrier-to-noise ratio, cycle slip, gradual accumulation of phase error, and pseudorange residual. Accordingly, we establish a multi-GNSS PPP mathematical model that is more suitable for GNSS observations from a smartphone. The stochastic model is composed of GNSS step function variances depending on carrier-to-noise ratio, and the robust Kalman filter is applied to parameter estimation. The multi-GNSS experimental results show that the proposed PPP method can significantly reduce the effect of poor satellite signal quality on positioning accuracy. Compared with the conventional PPP model, the root mean square (RMS) of GPS/BeiDou (BDS)/GLONASS static PPP horizontal and vertical errors in the initial 10 min decreased by 23.71% and 62.06%, respectively, and the horizontal positioning accuracy reached 10 cm within 100 min. Meanwhile, the kinematic PPP maximum three-dimensional positioning error of GPS/BDS/GLONASS decreased from 16.543 to 10.317 m.

miRNA-20a upregulates TAK1 and increases proliferation in osteosarcoma cells.

AIM: The aim of this study is to explore the function of miR-20a in osteosarcoma. MATERIALS & METHODS: miR-20a expression was measured by real-time PCR. miR-20a mimics, inhibitor and scramble siRNA were transfected into osteosarcoma cells to observe effects on colony formation and tumor growth. Moreover, relationships of miR-20a with TAK1 were investigated by western blot and luciferase activity. RESULTS: We found that miR-20a was downregulated in osteosarcoma, and overexpression of miR-20a reduced colony formation and tumor growth. Furthermore, the data revealed that the function of miR-20a was probably exerted via targeting the TAK1 expression. Overexpression of miR-20a sensitizes the osteosarcoma cells to chemotherapeutic drugs. CONCLUSION: Our data identify the role of miR-20a in osteosarcoma growth, indicating its potential application in chemotherapy.

Heading Estimation for Pedestrian Dead Reckoning Based on Robust Adaptive Kalman Filtering.

Pedestrian dead reckoning (PDR) using smart phone-embedded micro-electro-mechanical system (MEMS) sensors plays a key role in ubiquitous localization indoors and outdoors. However, as a relative localization method, it suffers from the problem of error accumulation which prevents it from long term independent running. Heading estimation error is one of the main location error sources, and therefore, in order to improve the location tracking performance of the PDR method in complex environments, an approach based on robust adaptive Kalman filtering (RAKF) for estimating accurate headings is proposed. In our approach, outputs from gyroscope, accelerometer, and magnetometer sensors are fused using the solution of Kalman filtering (KF) that the heading measurements derived from accelerations and magnetic field data are used to correct the states integrated from angular rates. In order to identify and control measurement outliers, a maximum likelihood-type estimator (M-estimator)-based model is used. Moreover, an adaptive factor is applied to resist the negative effects of state model disturbances. Extensive experiments under static and dynamic conditions were conducted in indoor environments. The experimental results demonstrate the proposed approach provides more accurate heading estimates and supports more robust and dynamic adaptive location tracking, compared with methods based on conventional KF.

Reference Device-Assisted Adaptive Location Fingerprinting.

Location fingerprinting suffers in dynamic environments and needs recalibration from time to time to maintain system performance. This paper proposes an adaptive approach for location fingerprinting. Based on real-time received signal strength indicator (RSSI) samples measured by a group of reference devices, the approach applies a modified Universal Kriging (UK) interpolant to estimate adaptive temporal and environmental radio maps. The modified UK can take the spatial distribution characteristics of RSSI into account. In addition, the issue of device heterogeneity caused by multiple reference devices is further addressed. To compensate the measuring differences of heterogeneous reference devices, differential RSSI metric is employed. Extensive experiments were conducted in an indoor field and the results demonstrate that the proposed approach not only adapts to dynamic environments and the situation of changing APs' positions, but it is also robust toward measuring differences of heterogeneous reference devices.

N6-methyladenosine modification of B7-H3 mRNA promotes the development and progression of colorectal cancer.

B7-H3 is a common oncogene found in various cancer types. However, the molecular mechanisms underlying abnormal B7-H3 expression and colorectal cancer (CRC) progression need to be extensively explored. B7-H3 was upregulated in human CRC tissues and its abnormal expression was correlated with a poor prognosis in CRC patients. Notably, gain- and loss-of-function experiments revealed that B7-H3 knockdown substantially inhibited cell proliferation, migration, and invasion in vitro, whereas exogenous B7-H3 expression yielded contrasting results. In addition, silencing of B7-H3 inhibited tumor growth in a xenograft mouse model. Mechanistically, our study demonstrated that the N6-methyladenosine (m6A) binding protein YTHDF1 augmented B7-H3 expression in an m6A-dependent manner. Furthermore, rescue experiments demonstrated that reintroduction of B7-H3 considerably abolished the inhibitory effects on cell proliferation and invasion induced by silencing YTHDF1. Our results suggest that the YTHDF1-m6A-B7-H3 axis is crucial for CRC development and progression and may represent a potential therapeutic target for CRC treatment.

How to Apply Intraoperative Ultrasound when Spinal Trauma Surgery Is Performed in the Lateral Decubitus Position?

OBJECTIVE: At present, intraoperative ultrasound was widely used in spinal surgery. But there have been no reports on the use of intraoperative ultrasound in lateral decubitus position spinal surgery. The authors' research objective was to describe the applications of intraoperative ultrasound in spinal trauma surgery when performed in the lateral decubitus position. METHODS: Six patients with polytrauma who underwent surgery for spinal trauma between June 2020 and March 2022 and could not be operated on using a posterior approach in the prone position. All six patients underwent surgery in the lateral decubitus position. During surgery, a capsular bag had been designed and surgical field can be filled with normal saline for acoustic coupling, and then ultrasound was used to observe and guide decompression, and assess injuries of the neural elements such as the spinal cord. The data of preoperative and postoperative (12 months) American Spinal Injury Association impairment scale (AIS), follow-up time, operation time, blood loss, ultrasound signal change of spinal cord, ultrasound guide decompression, internal fixation (12 months), and fracture healing(12 months) were collected. RESULTS: The study included four males and two females whose ages ranged from 19 to 56 years old (41.5 ± 13.06 years old). Follow-up times ranged from 12 to 20 months (14.33 ± 2.75 months). The operation times ranged from 195 to 248 mins (222.16 ± 16.86 mins). The estimated volume of blood loss ranged from 280 to 450 mL (383.33 ± 55.58 mL). The six cases' AIS (preoperative vs. postoperative) were A versus A, C versus D, A versus B, B versus B, B versus C, and B versus C. Intraoperative ultrasound was performed successfully in all patients using our designed method. Intraoperative ultrasound observation revealed varying degrees of changes in spinal cord echo in all patients. Intraoperative ultrasound provided excellent assistance in spinal cord decompression during surgery. The surgery was completed successfully with no surgery-related complications till the last follow-up. At the time of last follow-up (median time of 12 months) satisfactory fracture reduction and good internal fixation was confirmed on postoperative computed tomography scans and radiographs. CONCLUSIONS: The authors represented the technology of intraoperative ultrasound in spinal trauma surgery when performed in the lateral decubitus position. This technology solves how to apply intraoperative ultrasound in lateral decubitus position.

Protocol for the Chinese Real-World Evidence for Acute Spinal Cord Injury (ChiRES) study: a prospective, observational, multicentre cohort study of acute spinal cord injury.

INTRODUCTION: Spinal cord injury (SCI) is a catastrophic event with devastating physical, social and occupational consequences for patients and their families. The number of patients with acute SCI in China continues to grow rapidly, but there have been no large prospective cohort studies of patients with acute SCI. This proposed study aims to establish a multicentre, extensive sample cohort of clinical data and biological samples of patients in China, which would aid the systematisation and standardisation of clinical research and treatment of acute SCI, thus reducing the heavy burden of acute SCI on patients and society. METHODS AND ANALYSIS: The Chinese Real-World Evidence for Acute Spinal Cord Injury (ChiRES) study is an observational, multicentre cohort study of patients with acute SCI admitted to the Qilu Hospital of Shandong University and other participating centres with prospective collection of their clinical data and biological samples. We aim to recruit 2097 patients in this study. Demographics, disease history, emergency intervention information, motor and sensory examinations, surgical information, medication information and rehabilitation evaluation will be recorded. This will facilitate the development of a prediction model for complications and prognosis of patients with acute SCI and an evaluation of the current management of acute SCI. Among these variables, detailed information on surgical treatment will also be used to assess procedures for acute SCI treatment. Outcome measurements, including the International Standard for Neurological Classification of Spinal Cord Injury examinations, the occurrence of complications and death, will be performed repeatedly during follow-up. We will analyse imaging data and blood samples to develop SCI imaging markers and biomarkers. ETHICS AND DISSEMINATION: This study protocol has been approved by the Medical Ethics Committee of the Qilu Hospital of Shandong University and all other participating centres. The findings will be disseminated in peer-reviewed journals and academic conferences.

Safety and Efficacy of Cortical Bone Trajectory Screw Fixation Combined with Facet Fusion for the Treatment of Lumbar Degenerative Disease.

OBJECTIVE: The mainstream lumbar fusion surgeries have various shortcomings, such as complex operation, much invasion, and loss of lumbar function. How to minimize the surgical injury and to achieve better therapeutic effects has become the goal pursued by spine surgeons. This study introduces a cortical bone trajectory (CBT) screw fixation combined with facet fusion (FF), evaluates its safety and efficacy, and explores its advantages, in order to provide a reference for treatment of patients with single-level lumbar stenosis or grade I degenerative spondylolisthesis. METHODS: We retrospectively analyzed the clinical, radiological, and operative data of 167 patients with single-level lumbar stenosis or grade I degenerative spondylolisthesis who underwent FF or transforaminal lumbar interbody fusion (TLIF) from January 2013 to September 2019 in the spine surgery department of the Second Hospital of Shandong University. Patients were divided into four groups according to surgical method: group CBT-FF, CBT screw combined with FF; group PS-FF, pedicle screw (PS) combined with FF; group CBT-TLIF, CBT screw combined with TLIF; and group PS-TLIF, PS combined with TLIF. The operation time, estimated intraoperative blood loss, complications after surgery, visual analog scale (VAS), and Oswestry disability index (ODI) of the four groups were compared. The fusion was evaluated by anteroposterior and lateral X-ray, CT scan, and three-dimensional reconstruction. RESULTS: Twelve months after surgery, the fusion rate of four groups had no significantly statistical differences (p = 0.914). VAS and ODI scores were lower after surgery than before. Low back pain VAS scores 1 week after surgery in group CBT-FF and group CBT-TLIF were significantly lower than those in group PS-FF and group PS-TLIF (pCF/PF = 0.001, pCF/PT = 0.000, pPF/CT = 0.049, pCT/PT = 0.000). Low back pain VAS score 3 months after surgery was significantly lower in group CBT-FF than group PS-FF and group PS-TLIF (pCF/PF = 0.045, pCF/PT = 0.008). ODI score 1 week after surgery was significantly lower in group CBT-FF than group PS-FF, group CBT-TLIF, and group PS-TLIF (pCF/PF = 0.000, pCF/CT = 0.005, pCF/PT = 0.000, pCT/PT = 0.015). ODI score 3 months after surgery was significantly lower in group CBT-FF than group PS-FF, group CBT-TLIF, and group PS-TLIF (pCF/PF = 0.001, pCF/CT = 0.002, pCF/PT = 0.000). Incidence of complications did not significantly differ among the groups. CONCLUSION: CBT screw fixation combined with FF is a safe and efficacious procedure for patients with single-level lumbar stenosis or grade I degenerative spondylolisthesis. This minimally invasive approach of lumbar fusion can be simply and easily performed. Patients who undergo CBT screw fixation combined with FF recovered faster than TLIF.

[Promoting of angiogenesis and osteogenesis in radial critical bone defect regions of rabbits with nano-hydroxyapatite/collagen/PLA scaffolds plus endothelial progenitor cells].

OBJECTIVE: To explore the roles of nano-hydroxyapatite/collagen/PLA (nHAC/PLA) plus endothelial progenitor cells (EPCs) in repairing segmental bone defects of rabbit radius and enhancing angiogenesis and new bone formation. METHODS: EPCs isolated from New Zealand white rabbit bone marrow were cultured, identified and seeded into nHAC/PLA scaffolds. And the growth of EPCs in scaffolds was observed under scanning electron microscopy (SEM). Thirty-six were randomly divided into 3 groups to establish segmental bone defect models in radii. Two groups were implanted with EPCs/scaffolds constructs (group A, n = 16) and scaffolds alone (group B, n = 16) respectively. The remaining four rabbits were used as negative control (group C) and nothing was implanted. Animals were sacrificed at different timepoints and radii harvested to undergo radiological examination, histological examination and microvessle density test. RESULTS: These cells isolated from bone marrow were confirmed as EPCs. SEM showed that EPCs attached to the nHAC/PLA scaffolds, grew and proliferated well. Animal experiments revealed that radiological scores (5w: 2.25 ± 0.50 vs 1.00 ± 0.00; 10w: 2.75 ± 0.50 vs 1.75 ± 0.50; 15w: 4.25 ± 0.50 vs 3.0 ± 0.0; each P < 0.05), percentage of new bone formation area in bone defect regions (5w: 29.0% ± 3.5% vs 8.1% ± 0.8%; 10w: 63.4% ± 5.5% vs 16.6% ± 1.3%; 15w: 96.0% ± 4.3% vs 34.0% ± 6.6%; each P < 0.05) and microvessel density (2w: 13.5 ± 0.9 vs 4.3 ± 1.0; 5w:9.8 ± 0.7 vs 4.8 ± 0.3; 10w: 7.0 ± 0.4 vs 4.5 ± 0.4; each P < 0.05) in group A were significantly higher than those in group B. No new bone formation occurred in group C. CONCLUSION: The composite structure of EPCs-nHAC/PLA can enhance angiogenesis and new bone formation in segmental bone defects in rabbit radii. It may become a potential candidate of promoting revascularization of tissue engineering bone and repairing large bone defects.

Adverse outcomes of artificial pneumothorax under right bronchial occlusion for patients with thoracoscopic-assisted oesophagectomy in the prone position versus the semiprone position.

Background: There are few studies on the impact of body position on variations in circulation and breathing, and it has not been confirmed whether body position changes can reduce the pulmonary complications of thoracoscopic-assisted oesophagectomy. Methods: A single-center retrospective study included patients undergoing thoracoscopic-assisted oesophagectomy in the prone position or semiprone position between 1 July 2020, and 30 June 2021, at the Shanghai Chest Hospital. There were 103 patients with thoracoscopic-assisted oesophagectomy in the final analysis, including 43 patients undergoing thoracoscopic-assisted oesophagectomy in the prone position. Postoperative pulmonary complication (PPC) incidence was the primary endpoint. The incidence of cardiovascular and other complications was the secondary endpoint. Chest tube duration, patient-controlled anaesthesia (PCA) pressing frequency within 24 h, ICU stay, and the postoperative hospital length of stay (LOS) were also collected. Results: Compared with the semiprone position, the prone position decreased the incidence of atelectasis (12% vs. 30%, P = 0.032). Nevertheless, there were no considerable differences in the rates of cardiovascular and other complications, ICU stay, or LOS (P >0.05). Multivariable logistic regression analysis showed that the prone position (OR = 0.196, P = 0.011), no smoking (OR = 0.103, P <0.001), preoperative DLCO% ≥90% (OR = 0.230, P = 0.003), and an operative time <180 min (OR = 0.268, P = 0.006) were associated with less atelectasis. Conclusions: Our study shows that artificial pneumothorax under right bronchial occlusion one-lung ventilation for patients with thoracoscopic-assisted oesophagectomy in the prone position can decrease postoperative atelectasis compared with the semiprone position.

A comparison of neuromuscular blockade and reversal using cisatricurium and neostigmine with rocuronium and sugamadex on the quality of recovery from general anaesthesia for percutaneous closure of left atria appendage.

BACKGROUND: There is a growing interest in minimally invasive left atrial appendage closure therapies. However, for successful catheter surgery, it is necessary to achieve high-quality postoperative recovery. The aim of the study is to comparison of neuromuscular blockade and reversal using cisatricurium and neostigmine with rocuronium and sugamadex on the quality of recovery from general anaesthesia for percutaneous closure of left atria appendage. METHODS: Eighty-four patients who received percutaneous LAAC were randomly placed into two groups, general anesthesia and endotracheal intubation with either propofol-remifentanil-cisatracurium-neostigmine (group C) or propofol-remifentanil-rocuronium-sugammadex (group S). The QoR-40 questionnaire was used to assess recovery quality 6 h after surgery, and the time of spontaneous respiration, the time of consciousness recovery, the time of extubation, the duration in the postanaesthesia care unit (PACU), and the adverse events after awakening were collected. RESULTS: Compared with the group C, the group S demonstrated significantly higher individual QoR-40 dimension scores, a significantly shorter recovery time for spontaneous respiration and consciousness, time of extubation, and duration in the PACU, and a lower incidence of transient hypoxemia, agitation, nausea and vomiting and urinary retention. There was a non-significant trend for the length of stay in the hospital in both groups. CONCLUSIONS: General anesthesia and endotracheal intubation with propofol-remifentanil-rocuronium-sugammadex provided better quality of recovery, shorter anaesthesia duration, and lower incidence of hypoxemia and agitation. Neuromuscular blockade and reversal using rocuronium and sugamadex is better than with cisatricurium and neostigmine on the quality of recovery from general anaesthesia for percutaneous closure of left atria appendage. TRIAL REGISTRATION: chictr.org, ChiCTR2000031857. Registered on April 12, 2020.

The influence of carotid atherosclerosis on surgical outcomes of patients with cervical spondylotic myelopathy: A retrospective study.

ABSTRACT: The appearance of atherosclerosis in the carotid artery may be suggest the possibility of atherosclerosis in the spinal cord artery, which can cause spinal cord ischemia and further lead to neural element damage.According to the inclusion and exclude standard, there are 137 patients with cervical spondylotic myelopathy (CSM) incorporating retrospective analysis. These patients were consecutively admitted into The Second Hospital- Cheeloo College of Medicine-Shandong University from January 2016 to December 2018 and have accepted surgical treatment. All patients were examined by color Doppler ultrasound to detect carotid atherosclerosis before surgery. All patients were divided into 2 groups according to the presence or absence of carotid atherosclerosis: carotid atherosclerosis group (n = 88) and noncarotid atherosclerosis group (n = 49). All patients were followed up for at least 12 months after surgery. Demographic and surgery-related data were collected and analyzed to identify potential factors that affect the surgical outcomes in CSM.The average age of carotid atherosclerosis group (51 males and 37 females), and noncarotid atherosclerosis group (24 males and 25 females) were 62.02 ±â€Š10.34 years (range, 38-85 years) and 49.61 ±â€Š10.28 years (range, 26-67 years), respectively.In carotid atherosclerosis group: pre and postoperative modify Japanese Orthopedic Association Scores (mJOA score) were 11.58 ±â€Š1.82 and 14.36 ±â€Š1.64; the recovery rate of mJOA score was 45.57% ±â€Š13.28%. In noncarotid atherosclerosis group: pre and postoperative mJOA score were 12.00 ±â€Š2.11 and 15.04 ±â€Š1.70; the recovery rate of mJOA score was 53.90% ±â€Š13.22%. Univariate logistic regression analysis demonstrated that gender (P = .004), age ≥65 years (P = .001), duration of symptoms ≥12 months (P = .040), smoking history (P < .001), preoperative mJOA score ≤11 (P = .007) and carotid atherosclerosis (P = .004) were related to poor surgical outcomes. Multivariate logistic regression analysis showed significant correlations between poor surgical outcomes and age ≥65 years (P = .047), smoking history (P = .010), preoperative mJOA score ≤11 (P = .008) or carotid atherosclerosis (P = .047).Carotid atherosclerosis may be a risk factor for poor surgical outcomes in CSM.

[Influence of minor back trauma on surgical outcomes in patients with thoracic ossification of ligamentum flavum].

OBJECTIVE: To retrospectively explore the influences of minor back trauma on surgical outcomes in patients with thoracic ossification of ligamentum flavum (TOLF) and preliminarily detect its possible causes. METHODS: A total of 94 TOLF patients were divided into two groups according to the absence or presence of minor back trauma: MT (minor trauma, n = 16) and NT (no trauma, n = 78). They were compared in terms of gender, age, duration of symptoms, levels of involvement, numbers of involved segments, ratio of intramedullary signal changes (IMSC), pre- & post-operative JOA (Japanese Orthopedic Association) score, recovery rate (RR) at the final follow-up. Multiple regression analysis was employed to elucidate the causes related with the surgical outcomes. The MT group was further divided into two subgroups according to the intervals between trauma and surgery to clarify the influences of surgical timing on the efficacies. RESULTS: The JOA scores were 4.0 ± 1.4 and 8.4 ± 1.7 respectively in MT and NT groups at the final follow-up. The neurological status of patients improved in both groups (MT: P = 0.009, NT: P = 0.000). The patients were younger in MT groups (50 ± 11 years) than those in NT groups (58 ± 8 years) (P = 0.046). The ratio of IMSC was higher in MT groups (75.0%) than that in NT groups (25.6%) (P = 0.000). The pre- & post-operative JOA scores were lower in MT groups than those in NT groups (both P = 0.000). Multiple regression analysis revealed that the postoperative JOA score at the final follow-up was positively related with the preoperative JOA score (r = 0.60, P = 0.000) and negatively with trauma and IMSC (r = -1.82 and r = -1.87, P = 0.000) while the final postoperative RR were negatively related with trauma and IMSC (r = -26.26 and r = -33.70, P = 0.000). The surgical timing after trauma did not influence the efficacies (P = 0.147). CONCLUSION: The TOLF patients with minor back trauma have a worse post-operative recovery. A minor trauma might be a risk factor of adverse surgical outcomes.

Attitude and Heading Estimation for Indoor Positioning Based on the Adaptive Cubature Kalman Filter.

The demands for indoor positioning in location-based services (LBS) and applications grow rapidly. It is beneficial for indoor positioning to combine attitude and heading information. Accurate attitude and heading estimation based on magnetic, angular rate, and gravity (MARG) sensors of micro-electro-mechanical systems (MEMS) has received increasing attention due to its high availability and independence. This paper proposes a quaternion-based adaptive cubature Kalman filter (ACKF) algorithm to estimate the attitude and heading based on smart phone-embedded MARG sensors. In this algorithm, the fading memory weighted method and the limited memory weighted method are used to adaptively correct the statistical characteristics of the nonlinear system and reduce the estimation bias of the filter. The latest step data is used as the memory window data of the limited memory weighted method. Moreover, for restraining the divergence, the filter innovation sequence is used to rectify the noise covariance measurements and system. Besides, an adaptive factor based on prediction residual construction is used to overcome the filter model error and the influence of abnormal disturbance. In the static test, compared with the Sage-Husa cubature Kalman filter (SHCKF), cubature Kalman filter (CKF), and extended Kalman filter (EKF), the mean absolute errors (MAE) of the heading pitch and roll calculated by the proposed algorithm decreased by 4-18%, 14-29%, and 61-77% respectively. In the dynamic test, compared with the above three filters, the MAE of the heading reduced by 1-8%, 2-18%, and 2-21%, and the mean of location errors decreased by 9-22%, 19-31%, and 32-54% respectively by using the proposed algorithm for three participants. Generally, the proposed algorithm can effectively improve the accuracy of heading. Moreover, it can also improve the accuracy of attitude under quasistatic conditions.

Cryogel biocomposite containing chitosan-gelatin/cerium-zinc doped hydroxyapatite for bone tissue engineering.

The present examination includes manufacture and portrayal of cryogel bio-composite implants containing chitosan-gelatin (CS-GT), cerium-zinc doped hydroxyapatite (CS-GT/Ce-Zn-HA) by cryogelation technique. The prepared cryogel biocomposites (CS-GT/HA and CS-GT/Ce-Zn-HA) were described by scanning electron microscope (SEM) and X-Ray diffraction (XRD) contemplates. The expansion of Ce-Zn in the CS-GT implants essentially expanded growing, diminished swelling, expanded protein sorption, and expanded bactericidal movement. The CS-GT/Ce-Zn-HA biocomposite had non-toxic towards rodent osteoblast cells. So the created CS-GT/Ce-Zn-HA biocomposite has favorable and potential applications over the CS-GT/HA platforms for bone tissue engineering.

Percutaneous Vertebroplasty with Side-Opening Cannula or Front-Opening Cannula in the Treatment of Kummell Disease?

OBJECTIVE: To explore the effect of bone cement distribution, cement leakage, and clinical outcomes with side-opening cannula for bone cement injection in percutaneous vertebroplasty (PVP) in treatment of Kummell disease. METHODS: A prospective study of patients with Kummell disease undergoing PVP was conducted from April 2012 to September 2017. In total, 43 patients (11 males, 32 females) with Kummell disease who received bilateral PVP were included in the study. The patients were divided into front-opening cannulas (FOC) group with front-opening cannulas and side-opening cannulas (SOC) group with side-opening cannulas. All patients were followed up for 6 months. The patient general information such as gender, age, bone density, compression ratio, operative time, and location of fracture vertebrae were recorded. Visual analogue scale (VAS), Oswestry Disability Index (ODI), bone cement distribution, radiation exposure time, bone cement leakage rate and vertebral height, and kyphosis angle were measured and compared for two groups before surgery, 1 day and 6 months after surgery. RESULTS: A total of 43 patients were enrolled, including 11 males and 32 females, aged 61-84 years. The bone density (T value) was 2.5 ± 0.6 in FOC group and 2.4 ± 0.6 in SOC group (P > 0.05). The compression ratio and operative time were 36.1% ± 13.0%, 39.3 ± 7.9 min in FOC group and 35.2% ± 13.7%, 40.0 ± 10.7 min in SOC group (P > 0.05). There was no significance between FOC and SOC groups in the location of fracture vertebrae. All patients underwent at least 6 months of follow-up. At 6 months postoperatively, the VAS and ODI were significantly higher in the FOC group (3.0 ± 0.8, 35.7% ± 2.1%) than in the SOC group (1.3 ± 0.4, 18.6% ± 2.4%) (P < 0.05). The cement leakage rate of the SOC group was 4.8%, which was lower than that of the FOC group (31.8%, P < 0.05), and the bone cement distribution ratio was higher than that of the FOC group (63.1% ± 7.9% vs 40.5% ± 8.6%, P < 0.05). At 6 months after operation, the height of the anterior and posterior vertebral bodies of the patients in the SOC group restored better than the FOC group (anterior SOC: FOC 5.1 ± 0.5 mm vs 4.5 ± 0.5 mm; posterior SOC: FOC 0.6 ± 0.1 mm vs 0.3 ± 0.1 mm, P < 0.05), and the kyphosis correction was more obvious than patients in FOC group (SOC: FOC 8.5° ± 1.4° vs 4.6° ± 0.8°, P < 0.05). CONCLUSION: Percutaneous vertebroplasty with side-opening cannula is safe and effective in avoiding bone cement leakage, improving bone cement distribution, and restoring vertebral height.

The effect of bone marrow mesenchymal stem cell and nano-hydroxyapatite/collagen I/poly-L-lactic acid scaffold implantation on the treatment of avascular necrosis of the femoral head in rabbits.

For avascular necrosis of the femoral head (ANFH), repair and regeneration are difficult because of the edema and high pressure caused by continuous ischemia and hypoxia. Core decompression (CD) is a classic method for treating early ANFH before the collapse of the femoral head; however, its effect is still controversial. To improve the therapeutic effect of CD on ANFH, a novel tissue-engineered bone (TEB) was constructed by combining bone marrow mesenchymal stem cells (BMSCs) with nano-hydroxyapatite/collagen I/poly-L-lactic acid (nHAC/PLA) scaffolds and implanting the TEB into the bone tunnel of CD. Cell attachment was observed by scanning electron microscopy and hematoxylin and eosin staining. The authors' previous studies confirmed that nHAC/PLA is an excellent scaffold material with favorable biocompatibility and no cytotoxicity. A total of 24 New Zealand rabbits with ANFH were randomly divided into three groups, as follows: Group A (n=8), pure CD; group B (n=8), CD+nHAC/PLA; and group C (n=8), CD+BMSCs-nHAC/PLA. The favorable effect of BMSCs-nHAC/PLA on angiogenesis and bone formation in necrotic areas was further evaluated via radiographic and histological analyses. Computerized tomography (CT) scanning and H&E staining showed more capillaries and new osteoid tissue in group C compared with in groups B and A. Micro-CT showed that the new bone coverage rate and implanted material degradation degree were each increased in group C compared with in group B. These results indicate that BMSCs-nHAC/PLA scaffolds may improve the curative effect of CD and provide a strategy for treating ANFH.