Optical ReLU-like activation function based on a semiconductor laser with optical injection.

Artificial neural networks usually consist of successive linear multiply-accumulate operations and nonlinear activation functions. However, most optical neural networks only achieve the linear operation in the optical domain, while the optical implementation of activation function remains challenging. Here we present an optical ReLU-like activation function (with 180° rotation) based on a semiconductor laser subject to the optical injection in an experiment. The ReLU-like function is achieved in a broad regime above the Hopf bifurcation of the injection-locking diagram and is operated in the continuous-wave mode. In particular, the slope of the activation function is reconfigurable by tuning the frequency difference between the master laser and the slave laser.

Asynchronous photonic time-delay reservoir computing.

Time-delay reservoir computing uses a nonlinear node associated with a feedback loop to construct a large number of virtual neurons in the neural network. The clock cycle of the computing network is usually synchronous with the delay time of the feedback loop, which substantially constrains the flexibility of hardware implementations. This work shows an asynchronous reservoir computing network based on a semiconductor laser with an optical feedback loop, where the clock cycle (20 ns) is considerably different to the delay time (77 ns). The performance of this asynchronous network is experimentally investigated under various operation conditions. It is proved that the asynchronous reservoir computing shows highly competitive performance on the prediction task of Santa Fe chaotic time series, in comparison with the synchronous counterparts.

Diagnostic accuracy and potential covariates of artificial intelligence for diagnosing orthopedic fractures: a systematic literature review and meta-analysis.

OBJECTIVES: To systematically quantify the diagnostic accuracy and identify potential covariates affecting the performance of artificial intelligence (AI) in diagnosing orthopedic fractures. METHODS: PubMed, Embase, Web of Science, and Cochrane Library were systematically searched for studies on AI applications in diagnosing orthopedic fractures from inception to September 29, 2021. Pooled sensitivity and specificity and the area under the receiver operating characteristic curves (AUC) were obtained. This study was registered in the PROSPERO database prior to initiation (CRD 42021254618). RESULTS: Thirty-nine were eligible for quantitative analysis. The overall pooled AUC, sensitivity, and specificity were 0.96 (95% CI 0.94-0.98), 90% (95% CI 87-92%), and 92% (95% CI 90-94%), respectively. In subgroup analyses, multicenter designed studies yielded higher sensitivity (92% vs. 88%) and specificity (94% vs. 91%) than single-center studies. AI demonstrated higher sensitivity with transfer learning (with vs. without: 92% vs. 87%) or data augmentation (with vs. without: 92% vs. 87%), compared to those without. Utilizing plain X-rays as input images for AI achieved results comparable to CT (AUC 0.96 vs. 0.96). Moreover, AI achieved comparable results to humans (AUC 0.97 vs. 0.97) and better results than non-expert human readers (AUC 0.98 vs. 0.96; sensitivity 95% vs. 88%). CONCLUSIONS: AI demonstrated high accuracy in diagnosing orthopedic fractures from medical images. Larger-scale studies with higher design quality are needed to validate our findings. KEY POINTS: • Multicenter study design, application of transfer learning, and data augmentation are closely related to improving the performance of artificial intelligence models in diagnosing orthopedic fractures. • Utilizing plain X-rays as input images for AI to diagnose fractures achieved results comparable to CT (AUC 0.96 vs. 0.96). • AI achieved comparable results to humans (AUC 0.97 vs. 0.97) but was superior to non-expert human readers (AUC 0.98 vs. 0.96, sensitivity 95% vs. 88%) in diagnosing fractures.

Association Between Health Literacy and Enhanced Recovery After Surgery Protocol Adherence and Postoperative Outcomes Among Patients Undergoing Colorectal Cancer Surgery: A Prospective Cohort Study.

BACKGROUND: Low health literacy (HL) adversely affects medical adherence and health outcomes in patients with chronic diseases. However, the association between HL and enhanced recovery after surgery (ERAS) adherence and postoperative outcomes has not been investigated in patients undergoing colorectal surgery. METHODS: The data of all patients from a single academic institution who underwent colorectal surgery on an ERAS pathway from January 2019 to July 2020 were prospectively collected. HL levels were assessed using the Brief Health Literacy Screen (BHLS), a proven tool that was used by surgeons after recruitment. According to the HL score, the participants were categorized into low HL (≤9 points) and high HL (10-15 points) groups. The primary outcome was ERAS adherence. Adherence was measured in 22 perioperative elements, and high adherence was defined as adherence to 17 to 22 elements. Secondary outcomes included postoperative complications, hospital length of stay (LOS), hospital charges, mortality, and readmissions. RESULTS: Of the 865 eligible patients, the high HL group consisted of 329 patients (38.0%), and the low HL group contained 536 patients (62.0%). After propensity score matching (1:1), 240 unique pairs of patients with similar characteristics were selected. Patients with high HL levels had a significantly higher rate of high adherence to ERAS standards than those with low HL levels (55% vs 25.8%; adjusted P < .001). In terms of adherence to each item, high HL levels were significantly associated with higher adherence to preoperative optimization (90.8% vs 71.7%; adjusted P < .001), postoperative gum chewing (59.2% vs 44.6%; adjusted P = .01), early feeding (59.2% vs 31.3%; adjusted P < .001), and early mobilization (56.7% vs 30.4%; adjusted P < .001). In the overall study population, adjusted logistic regression analyses also showed that high HL levels were associated with a significantly increased rate of high adherence when compared with low HL levels (adjusted odds ratio [OR], 3.57; 95% confidence interval (CI), 2.50-5.09; P < .001). In addition, low HL levels were associated with a significantly higher incidence of postoperative complications (32.1% vs 20.8%; P < .01), longer hospital LOS (9 [interquartile range {IQR}, 7-11] vs 7 [IQR, 6-9] d; P < .001), and higher hospital charges (10,489 [IQR, 8995-11942] vs 8466 [IQR, 7733-9384] dollar; P < .001) among propensity-matched patients. However, there were no differences in the mortality and readmission rates between the HL groups. CONCLUSIONS: Low HL levels were associated with lower adherence to ERAS elements among propensity-matched patients undergoing colorectal surgery.

Preliminary results in anterior cervical discectomy and fusion with the uncovertebral joint fusion cage in a goat model.

OBJECTIVE: To preliminarily evaluate the safety and efficacy of the uncovertebral joint fusion cage in a goat model of cervical spine interbody fusion. METHODS: Twenty-four healthy adult goats were randomly assigned to one of the two following groups: Group A, goats were implanted with an uncovertebral joint fusion cage combined with a local autograft and Group B, goats were implanted with a non-profile cage filled with a local autograft. The goats were prospectively evaluated for 24 weeks and then were sacrificed for evaluation. X-rays, CT and micro-CT scanning, and undecalcified bone histological analysis were used for the evaluation of fusion. RESULTS: 75.0% (9/12) of the goats in Group A were evaluated as having fusion at 12 weeks, compared to 41.7% (5/12) in Group B. 83.3% (10/12) of the goats in Group A were evaluated as having fusion at 24 weeks compared to 58.3% (7/12) in Group B. The fusion grading scores in Group A were significantly higher than that in Group B both at 12 weeks and 24 weeks (P < 0.05). Micro-CT scanning and undecalcified bone histological analysis showed that new bone formation can be obviously found in the bilateral uncovertebral joint. The bone volume fraction (BV/ TV) in Group A (23.59 ± 4.43%) was significantly higher than Group B (16.16 ± 4.21%), with P < 0.05. CONCLUSIONS: Preliminary results of this study demonstrated that uncovertebral joint fusion cage is effective for achieving early bone formation and fusion without increase of serious complications.

[Impact of deep slow-wave sleep deprivation on oxidative stress response of the testis tissue in rats].

OBJECTIVE: To investigate the influence of deep slow-wave sleep deprivation on the oxidative stress of testicular tissue in rats. METHODS: Thirty-six 5-week-old male Wistar rats were equally randomized into deep slow-wave sleep deprivation group (SD1), deep slow-wave sleep and duration sleep deprivation group ( SD2), and a cage control group (CC). The rat model of deep slow-wave sleep deprivation was established using the flowerpot technique. The rats in the SD1 group were interfered every 24 minutes and deprived of 12 hours of sleep at night, those in the SD2 group deprived of 8 minutes of sleep at an interval of 24 minutes and 12 hours of sleep at night, and those in the CC group exposed to 12 hours of daylight and 12 hours of darkness. After 28 days, all the rats were executed for measurement of the testis volume and protein content, determination of the methane dicarboxylic aldehyde (MDA) level and activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and observation of the pathological changes in the testicular tissue under the microscope. RESULTS: Compared with the CC group, the rats in the SD1 and SD2 groups showed significantly reduced body weight (ï¼»268.5 ± 1.6ï¼½ vs ï¼»248.1 ± 25.1ï¼½andï¼»232.9 ± 10.1ï¼½g, P<0.05) and increased relative testis mass (ï¼»50.0 ± 1.3ï¼½ vs ï¼»57.9 ± 6.1ï¼½ and ï¼»54.9 ± 3.5ï¼½ ×10⁻², P<0.05). Statistically significant differences were found between the CC and SD2 groups in the contents of protein (ï¼»6.3 ± 1.4ï¼½ vs ï¼»4.5 ± 0.9ï¼½ gpro/L, P<0.05) and MDA (ï¼»1.1 ± 0.1ï¼½ vs ï¼»1.3 ± 0.3ï¼½ nmol/mgpro, P<0.05) and the activities of SOD (ï¼»104.3 ± 33.1ï¼½ vs ï¼»135.2 ± 26.9ï¼½ U/mgpro, P<0.05) and GSH-Px (ï¼»15.6 ± 4.0ï¼½ vs ï¼»21.7 ± 4.3ï¼½ U/mgpro, P<0.05), but not between the CC and SD1 groups (P>0.05). The lumens in the testis were narrowed, with obvious hyperplasia, hyperemia and edema in the peripheral interstitial tissue, but no significant pathologic changes were observed in the testis tissue of the SD1 group. CONCLUSIONS: Long-term deprivation of deep slow-wave sleep impairs the structure of the testis tissue and induces oxidative stress response in rats.

Computer-aided multiview tumor detection for automated whole breast ultrasound.

Automated whole breast ultrasound (ABUS) has become a popular screening tool in recent years. To reduce the review time and misdetection from ABUS images by physicians, a computer-aided detection (CADe) system for ABUS images based on a multiview method is proposed in this study. A total of 58 pathology-proven lesions from 41 patients were used to evaluate the performance of the system. In the proposed CADe system, the fuzzy c-mean clustering method was applied to detect tumor candidates from these ABUS images. Subsequently, the tumor likelihoods of these candidates could be estimated by a logistic linear regression model based on the intensity, morphology, location, and size features in the transverse, longitudinal, and coronal views. Finally, the multiview tumor likelihoods of the tumor candidates could be obtained from the estimated tumor likelihoods of the three views, and the tumor candidates with high multiview tumor likelihoods were regarded as the detected tumors in the proposed system. The sensitivities of the multiview tumor detection for selecting 5, 10, 20, and 30 tumor candidates with the largest multiview tumor likelihoods were 79.31%, 86.21%, 96.55%, and 98.28%, respectively.

The association of cervical sagittal alignment with anterior bone loss following single-level anterior cervical surgery.

Background: Anterior bone loss (ABL) is a common phenomenon after cervical disc replacement (CDR), which can also be observed after anterior cervical discectomy and fusion (ACDF). This study aimed to investigate the incidence and severity of ABL in single-level CDR and ACDF and explore the association of cervical sagittal alignment with ABL. Methods: This is a single-center retrospective cohort study. A total of 113 patients treated with CDR and 99 patients treated with ACDF were retrospectively reviewed from January 2014 to December 2018 in West China Hospital. Radiological data were collected at pre-operation, 1 week, 3 months postoperatively, and the last follow-up. The incidence and severity of ABL after both CDR and ACDF were evaluated. Cervical sagittal alignment parameters, including C0-C2 angle, cervical lordosis (CL), C2-C7 sagittal vertical axis (cSVA), T1 slope, functional spinal unit angle, disc angle, and surgical level slope, were evaluated. Results: ABL was identified in 75 (66.4%) patients in the CDR group and 57 (57.6%) patients in the ACDF group. There were no significant differences in the incidence, severity, and location of ABL between the ACDF and CDR groups. For patients who underwent ACDF, the proportion of females was significantly higher in the ABL group (64.9% vs. 33.3%, P=0.002), whereas the body mass index (BMI) was significantly lower in the ABL group compared to the non-ABL group (22.72±3.09 vs. 24.60±3.04, P=0.002). No effect of ABL on the short-term clinical outcomes of ACDF and CDR was observed. In the ACDF group, patients with ABL had significantly smaller postoperative CL (11.83°±8.24° vs. 15.25°±8.32°, P=0.04) and cSVA (17.77±10.08 vs. 23.35±9.86 mm, P=0.007). In the CDR group, no significant differences were found in the cervical sagittal parameters between patients with and without ABL (CL: 12.58±8.70 vs. 15.46±8.50, P=0.10; cSVA: 20.95±8.54 vs. 19.40±9.43, P=0.38). Conclusions: ABL is common after both CDR and ACDF with comparable incidence and severity. Cervical sagittal alignment was closely related to ABL after ACDF yet had less influence on ABL after CDR.

Effects of propofol on expression of hippocampal neuronal nitric oxide synthase and carboxy-terminal PDZ ligand of neuronal nitric oxide synthase in stressed rats undergoing electroconvulsive shock.

OBJECTIVES: This study aimed at investigating the effects of propofol on the expression of hippocampal neuronal nitric oxide synthase (nNOS) and carboxy-terminal PDZ ligand of nNOS (CAPON) in stressed rats after electroconvulsive shock (ECS). METHODS: Sprague-Dawley rats were stressed repeatedly for 28 days to establish a stressed model. Forty stressed rats were randomly divided into 4 groups (n = 10 for each group): the stressed group (unapplied group), propofol group (applied with intraperitoneal injection of propofol 80 mg/kg for 7 days), ECS group (applied with ECS and intraperitoneal injection of normal saline 8 mL/kg), or propofol + ECS group (applied with ECS and intraperitoneal injection of propofol 80 mg/kg). Sucrose preference test, open-field test, and Morris water maze were used to assess behavioral changes. Immunohistochemistry was carried out to measure the expression of nNOS and CAPON in hippocampal CA1, CA3, and DG areas. RESULTS: Rats in the ECS and propofol + ECS groups had higher sucrose preference percentages and open-field scores when compared with the stressed group. Rats in the ECS group exhibited longer escape latency, shorter space exploration time, up-regulated expression of nNOS, down-regulated expression of CAPON, and increased ratio of nNOS/CAPON in hippocampus. Compared with the ECS group, the propofol + ECS group exhibited shorter escape latency, longer space exploration time, down-regulated expression of nNOS, up-regulated expression of CAPON in hippocampus, and lower nNOS/CAPON values. CONCLUSIONS: Propofol may alleviate ECS-induced impairment of learning and memory in stressed rats by inhibiting excessive expression of nNOS and enhancing the expression of CAPON to maintain the balance between nNOS and CAPON in hippocampus.

Sambucus williamsii Hance maintains bone homeostasis in hyperglycemia-induced osteopenia by reversing oxidative stress via cGMP/PKG signal transduction.

BACKGROUND: Sambucus williamsii Hance (SWH) has effectively been adopted to treat joint and bone disorders. Diabetes-induced osteopenia (DOP) is caused primarily by impaired bone formation as a result of hyperglycemia. We had previously demonstrated that SWH extract accelerated fracture healing and promoted osteoblastic MC3T3-E1 cell proliferation and osteogenic differentiation. This study assessed the impacts of SWH extract on diabetes-induced bone loss and explored the mechanisms underlying its osteoprotective effects. METHODS: This work employed MC3T3-E1 cell line for evaluating how SWH extract affected osteogenesis, oxidative stress (OS), and the underlying mechanism in vitro. Streptozotocin-induced osteopenia mouse model was applied with the purpose of assessing SWH extract's osteoprotection on bone homeostasis in vivo. RESULTS: The increased OS of MC3T3-E1 cells exposed to high glucose (HG) was largely because of the upregulation of pro-oxidant genes and the downregulation of antioxidant genes, whereas SWH extract reduced the OS by modulating NADPH oxidase-4 and thioredoxin-related genes by activating cyclic guanosine monophosphate (cGMP) production and increasing the level of cGMP-mediated protein kinase G type-2 (PKG2). The oral administration of SWH extract maintained bone homeostasis in type 1 diabetes mellitus (T1DM) mice by enhancing osteogenesis while decreasing OS. In bones from hyperglycemia-induced osteopenia mice and HG-treated MC3T3-E1 cells, the SWH extract achieved the osteoprotective effects through activating the cGMP/PKG2 signaling pathway, upregulating the level of antioxidant genes, as well as downregulating the level of pro-oxidant genes. CONCLUSION: SWH extract exerts osteoprotective effects on hyperglycemia-induced osteopenia by reversing OS via cGMP/PKG signal transduction and is a potential therapy for DOP.

Biomechanical performance of the novel assembled uncovertebral joint fusion cage in single-level anterior cervical discectomy and fusion: A finite element analysis.

Introduction: Anterior cervical discectomy and fusion (ACDF) is widely accepted as the gold standard surgical procedure for treating cervical radiculopathy and myelopathy. However, there is concern about the low fusion rate in the early period after ACDF surgery using the Zero-P fusion cage. We creatively designed an assembled uncoupled joint fusion device to improve the fusion rate and solve the implantation difficulties. This study aimed to assess the biomechanical performance of the assembled uncovertebral joint fusion cage in single-level ACDF and compare it with the Zero-P device. Methods: A three-dimensional finite element (FE) of a healthy cervical spine (C2-C7) was constructed and validated. In the one-level surgery model, either an assembled uncovertebral joint fusion cage or a zero-profile device was implanted at the C5-C6 segment of the model. A pure moment of 1.0 Nm combined with a follower load of 75 N was imposed at C2 to determine flexion, extension, lateral bending, and axial rotation. The segmental range of motion (ROM), facet contact force (FCF), maximum intradiscal pressure (IDP), and screw-bone stress were determined and compared with those of the zero-profile device. Results: The results showed that the ROMs of the fused levels in both models were nearly zero, while the motions of the unfused segments were unevenly increased. The FCF at adjacent segments in the assembled uncovertebral joint fusion cage group was less than that that of the Zero-P group. The IDP at the adjacent segments and screw-bone stress were slightly higher in the assembled uncovertebral joint fusion cage group than in those of the Zero-P group. Stress on the cage was mainly concentrated on both sides of the wings, reaching 13.4-20.4 Mpa in the assembled uncovertebral joint fusion cage group. Conclusion: The assembled uncovertebral joint fusion cage provided strong immobilization, similar to the Zero-P device. When compared with the Zero-P group, the assembled uncovertebral joint fusion cage achieved similar resultant values regarding FCF, IDP, and screw-bone stress. Moreover, the assembled uncovertebral joint fusion cage effectively achieved early bone formation and fusion, probably due to proper stress distributions in the wings of both sides.

Exploring Spatio-Spectral Electroencephalogram Modulations of Imbuing Emotional Intent During Active Piano Playing.

Imbuing emotional intent serves as a crucial modulator of music improvisation during active musical instrument playing. However, most improvisation-related neural endeavors have been gained without considering the emotional context. This study attempts to exploit reproducible spatio-spectral electroencephalogram (EEG) oscillations of emotional intent using a data-driven independent component analysis framework in an ecological multiday piano playing experiment. Through the four-day 32-ch EEG dataset of 10 professional players, we showed that EEG patterns were substantially affected by both intra- and inter-individual variability underlying the emotional intent of the dichotomized valence (positive vs. negative) and arousal (high vs. low) categories. Less than half (3-4) of the 10 participants analogously exhibited day-reproducible ( ≥ three days) spectral modulations at the right frontal beta in response to the valence contrast as well as the frontal central gamma and the superior parietal alpha to the arousal counterpart. In particular, the frontal engagement facilitates a better understanding of the frontal cortex (e.g., dorsolateral prefrontal cortex and anterior cingulate cortex) and its role in intervening emotional processes and expressing spectral signatures that are relatively resistant to natural EEG variability. Such ecologically vivid EEG findings may lead to better understanding of the development of a brain-computer music interface infrastructure capable of guiding the training, performance, and appreciation for emotional improvisatory status or actuating music interaction via emotional context.

Clinical Features of Urticaria: Results From a Hospital-Based Multicenter Study in China.

Background: The clinical features of urticaria have not been fully illustrated. Objectives: To demonstrate clinical features of urticaria in different areas of southern and northern China. Methods: In this hospital-based multicenter study, outpatients with urticaria filled in a questionnaire during the initial visit and follow-up (once per week, lasting for a month). Results: Overall, 1,715 outpatients with urticaria with a mean age of 37.86 ± 16.08 years (range = 0.5-87 years) were recruited. The median disease duration was 1.94 ± 4.31 years (range = 0-58 years). More itching was observed in the northern areas higher than that in the southern areas (99.5 vs 94.1%, P < 0.001). The incidence of pain, arthralgia, and family history in southern areas was higher than that in northern areas (5.1 vs 1.1%, 9.6 vs 0, 10.6% vs 3.2%, P < 0.001). The leading subtypes of specified urticaria were chronic spontaneous urticaria (81.4%) and symptomatic dermographism (35.9%). The incidence of symptomatic dermographism and cold urticaria in the southern areas was lower than that in the northern areas (31.8 vs. 50.3%, 4 vs. 8.5%, P < 0.001). Allergic diseases were the most common concomitant disorders of urticaria. More than half of the patients had to avoid certain food, such as fish-prawn-crab (30.7%) and alcohol (20%). Ebastine (41.1%) was the most commonly prescribed drug. The disease duration negatively correlated with the severity of itching and number of wheals (>50/24H) (Spearman's rank correlation test, p < 0.001). Conclusion: This study provides a profile of clinical characteristics of urticaria in China and filled the gap in the field of regional comparative studies on urticaria.

Metastatic Ceruminous Adenoid Cystic Carcinoma of the Lumbar Spine Causing Neurological Compromise: A Case Report.

Background: Ceruminous glands are modified apocrine glands of the external auditory canal (EAC). Malignant tumours within the ceruminous glands are extremely rare, and the most common histological type is adenoid cystic carcinoma (ADCC), which has high recurrence and metastasis risks. Although a few cases of metastatic ADCC from other head and neck glands have been reported, metastatic ADCC originating from the ceruminous gland are extremely rare. Case presentation: We present an unusual case of spinal metastases of ADCC from ceruminous glands. A 61-year-old woman complaining of low back pain and both lower limbs pain was referred to our department. The primary ceruminous tumour was resected 26 years ago and recurred 6 years later, which was treated by radiotherapy. Three years ago, she presented with low back pain and was diagnosed as multiple lungs and bone metastases. The patient underwent tumour excision, decompression and fusion. The biopsy revealed metastatic ADCC. The symptoms were alleviated after surgery. Conclusions: ADCC of EAC is a pernicious malignant tumour that is characterized by slow-growing patterns and a high predisposition to recurrence and metastasis. Differential diagnoses of ADCC and benign tumours in the EAC are challenging, particularly at early stages. We report a rare case of ceruminous ADCC with a prolonged clinical history as well as spinal metastasis and highlight the significance of regular follow-ups for patients undergoing tumour excision in the EAC.

Effect of perioperative steroids application on dysphagia, fusion rate, and visual analogue scale (VAS) following anterior cervical spine surgery: A meta-analysis of 14 randomized controlled trials (RCTs).

Objective: To conduct a high-level meta-analysis of the RCTs to evaluate perioperative steroids use in the management of fusion rate, dysphagia, and VAS following anterior cervical spine surgery for up to 1 year. Methods: We searched the database PubMed, EMBASE, Web of Science, Cochrane Library, Google Scholar, Ovid, and ClinicalTrials.gov without time restriction to identify RCTs that evaluate the effectiveness of perioperative steroids after anterior cervical spine surgery. A subgroup analysis was undertaken to investigate the effects of intravenous and local steroids. This study was registered in the PROSPERO database prior to initiation (CRD42022313444). Results: A total of 14 RCTs were eligible for final inclusion. This meta-analysis showed that steroids could achieve lower dysphagia rate (p < 0.001), severe dysphagia rate within 1 year (p < 0.001), lower VAS scores at both 1 day (p = 0.005), 2 weeks (p < 0.001) and shorter hospital stay (p = 0.014). However, there was no significant difference between the two groups regarding operation time (p = 0.670), fusion rates (p = 0.678), VAS scores at 6 months (p = 0.104) and 1 year (p = 0.062). There was no significant difference between intravenous and local steroid administration regarding dysphagia rates (p = 0.82), fusion rate (p = 1.00), and operative time (p = 0.10). Conclusion: Steroids intravenously or locally following anterior cervical spine surgery can reduce incidence and severity of dysphagia within 1 year, VAS score within 2 weeks, and shorten the length of hospital stay without affecting fusion rates, increasing the operating time, VAS score at 6 months and 1 year.

Biomechanical Evaluation of Intervertebral Fusion Process After Anterior Cervical Discectomy and Fusion: A Finite Element Study.

Introduction: Anterior cervical discectomy and fusion (ACDF) is a widely accepted surgical procedure in the treatment of cervical radiculopathy and myelopathy. A solid interbody fusion is of critical significance in achieving satisfactory outcomes after ACDF. However, the current radiographic techniques to determine the degree of fusion are inaccurate and radiative. Several animal experiments suggested that the mechanical load on the spinal instrumentation could reflect the fusion process and evaluated the stability of implant. This study aims to investigate the biomechanical changes during the fusion process and explore the feasibility of reflecting the fusion status after ACDF through the load changes borne by the interbody fusion cage. Methods: The computed tomography (CT) scans preoperatively, immediately after surgery, at 3 months, and 6 months follow-up of patients who underwent ACDF at C5/6 were used to construct the C2-C7 finite element (FE) models representing different courses of fusion stages. A 75-N follower load with 1.0-Nm moments was applied to the top of C2 vertebra in the models to simulate flexion, extension, lateral bending, and axial rotation with the C7 vertebra fixed. The Von Mises stress at the surfaces of instrumentation and the adjacent intervertebral disc and force at the facet joints were analyzed. Results: The facet contact force at C5/6 suggested a significantly stepwise reduction as the fusion proceeded while the intradiscal pressure and facet contact force of adjacent levels changed slightly. The stress on the surfaces of titanium plate and screws significantly decreased at 3 and 6 months follow-up. A markedly changed stress distribution in extension among three models was noted in different fusion stages. After solid fusion is achieved, the stress was more uniformly distributed interbody fusion in all loading conditions. Conclusions: Through a follow-up study of 6 months, the stress on the surfaces of cervical instrumentation remarkably decreased in all loading conditions. After solid intervertebral fusion formed, the stress distributions on the surfaces of interbody cage and screws were more uniform. The stress distribution in extension altered significantly in different fusion status. Future studies are needed to develop the interbody fusion device with wireless sensors to achieve longitudinal real-time monitoring of the stress distribution during the course of fusion.

Quality of online video resources concerning patient education for neck pain: A YouTube-based quality-control study.

Background: More than 70 percent of the world's population is tortured with neck pain more than once in their vast life, of which 50-85% recur within 1-5 years of the initial episode. With medical resources affected by the epidemic, more and more people seek health-related knowledge via YouTube. This article aims to assess the quality and reliability of the medical information shared on YouTube regarding neck pain. Methods: We searched on YouTube using the keyword "neck pain" to include the top 50 videos by relevance, then divided them into five and seven categories based on their content and source. Each video was quantitatively assessed using the Journal of American Medical Association (JAMA), DISCERN, Global Quality Score (GQS), Neck Pain-Specific Score (NPSS), and video power index (VPI). Spearman correlation analysis was used to evaluate the correlation between JAMA, GQS, DISCERN, NPSS and VPI. A multiple linear regression analysis was applied to identify video features affecting JAMA, GQS, DISCERN, and NPSS. Results: The videos had a mean JAMA score of 2.56 (SD = 0.43), DISCERN of 2.55 (SD = 0.44), GQS of 2.86 (SD = 0.72), and NPSS of 2.90 (SD = 2.23). Classification by video upload source, non-physician videos had the greatest share at 38%, and sorted by video content, exercise training comprised 40% of the videos. Significant differences between the uploading sources were observed for VPI (P = 0.012), JAMA (P < 0.001), DISCERN (P < 0.001), GQS (P = 0.001), and NPSS (P = 0.007). Spearman correlation analysis showed that JAMA, DISCERN, GQS, and NPSS significantly correlated with each other (JAMA vs. DISCERN, p < 0.001, JAMA vs. GQS, p < 0.001, JAMA vs. NPSS, p < 0.001, DISCERN vs. GQS, p < 0.001, DISCERN vs. NPSS, p < 0.001, GQS vs. NPSS, p < 0.001). Multiple linear regression analysis suggested that a higher JAMA score, DISCERN, or GQS score were closely related to a higher probability of an academic, physician, non-physician or medical upload source (P < 0.005), and a higher NPSS score was associated with a higher probability of an academic source (P = 0.001) than of an individual upload source. Conclusions: YouTube videos pertaining to neck pain contain low quality, low reliability, and incomplete information. Patients may be put at risk for health complications due to inaccurate, and incomplete information, particularly during the COVID-19 crisis. Academic groups should be committed to high-quality video production and promotion to YouTube users.

Association of Craniocervical Sagittal Alignment With the Outcomes of Cervical Disc Replacement.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To explore the association between craniocervical sagittal balance and clinical and radiological outcomes of cervical disc replacement (CDR). METHODS: Patients who underwent 1-level and 2-level CDR were retrospectively analyzed. Clinical outcomes were evaluated using scores on the Japanese Orthopaedic Association (JOA), Visual Analogue Scale (VAS), and Neck Disability Index (NDI). The craniocervical sagittal alignment parameters, including the C0-C2 Cobb angle, C2-C7 Cobb angle, C2 slope, T1 slope, C2-C7 sagittal vertical axis (SVA), C1-C7 SVA, the center of gravity of the head (CGH)-C7 SVA, and range of motion (ROM) at the surgical segments were measured. RESULTS: A total of 169 patients were involved. Significantly lower pre- and postoperative C2 slope and CGH-C7 SVA were found in arthroplasty levels with better ROMs. Patients with a higher preoperative C2 slope and CGH-C7 SVA had lower cervical lordosis and ROM after surgery. There were no significant differences in the clinical outcomes between patients with different sagittal balance statuses. C2-C7 SVA and CGH-C7 SVA were significantly associated with radiographic adjacent segment pathology (rASP). CONCLUSION: Craniocervical sagittal balance is associated with cervical lordosis and ROM at the index level after CDR. A higher preoperative SVA is related to the presence and progression of rASP. A relationship between sagittal alignment and clinical outcomes was not observed.

SeUneter: Channel attentive U-Net for instance segmentation of the cervical spine MRI medical image.

In recent years, cervical spondylosis has become one of the most common chronic diseases and has received much attention from the public. Magnetic resonance imaging (MRI) is the most widely used imaging modality for the diagnosis of degenerative cervical spondylosis. The manual identification and segmentation of the cervical spine on MRI makes it a laborious, time-consuming, and error-prone process. In this work, we collected a new dataset of 300 patients with a total of 600 cervical spine images in the MRI T2-weighted (T2W) modality for the first time, which included the cervical spine, intervertebral discs, spinal cord, and spinal canal information. A new instance segmentation approach called SeUneter was proposed for cervical spine segmentation. SeUneter expanded the depth of the network structure based on the original U-Net and added a channel attention module to the double convolution of the feature extraction. SeUneter could enhance the semantic information of the segmentation and weaken the characteristic information of non-segmentation to the screen for important feature channels in double convolution. In the meantime, to alleviate the over-fitting of the model under insufficient samples, the Cutout was used to crop the pixel information in the original image at random positions of a fixed size, and the number of training samples in the original data was increased. Prior knowledge of the data was used to optimize the segmentation results by a post-process to improve the segmentation performance. The mean of Intersection Over Union (mIOU) was calculated for the different categories, while the mean of the Dice similarity coefficient (mDSC) and mIOU were calculated to compare the segmentation results of different deep learning models for all categories. Compared with multiple models under the same experimental settings, our proposed SeUneter's performance was superior to U-Net, AttU-Net, UNet++, DeepLab-v3+, TransUNet, and Swin-Unet on the spinal cord with mIOU of 86.34% and the spinal canal with mIOU of 73.44%. The SeUneter matched or exceeded the performance of the aforementioned segmentation models when segmenting vertebral bodies or intervertebral discs. Among all models, SeUneter achieved the highest mIOU and mDSC of 82.73% and 90.66%, respectively, for the whole cervical spine.