A two-step neural network-based guiding system for obtaining reliable radiographs for critical shoulder angle measurement.

Background: The critical shoulder angle (CSA) has been reported to be highly associated with rotator cuff tears (RCTs) and an increased risk of RCT re-tears. However, the measurement of the CSA is greatly affected by the malpositioning of the shoulder. To address this issue, a two-step neural network-based guiding system was developed to obtain reliable CSA radiographs, and its feasibility and accuracy was evaluated. Methods: A total of 1,754 shoulder anteroposterior (AP) radiographs were retrospectively acquired to train and validate a two-step neural network-based guiding system to obtain reliable CSA radiographs. The study included patients aged 18 years or older who underwent X-rays and/or computed tomography (CT) scans of the shoulder. Patients who had undergone shoulder surgery, had a confirmed fracture, or were diagnosed with a musculoskeletal tumor or glenoid defect were excluded from the study. The system consisted of a two-step neural network that in the first step, localized the region of interest of the shoulder, and in the second step, classified the radiography according to type [i.e., 'forward' when the non-overlapping coracoid process is above the glenoid rim, 'backward' when the non-overlapping coracoid process is below or aligned with the glenoid rim, a ratio of the transverse to longitudinal diameter of the glenoid projection (RTL) ≤0.25, or a RTL >0.25]. The performance of the model was assessed in an offline, prospective manner, focusing on the sensitivity and specificity for the forward, backward, RTL ≤0.25, or RTL >0.25 types (denoted as SensF, B, -, + and SpecF, B, -, +, respectively), and Cohen's kappa was also reported. Results: Of 273 cases in the offline prospective test, the SensF, SensB, Sens-, and Sens+ were 88.88% [95% confidence interval (CI): 50.67-99.41%], 94.11% (95% CI: 82.77-98.47%), 96.96% (95% CI: 91.94-99.02%), and 95.06% (95% CI: 87.15-98.40%), respectively. The SpecF, SpecB, Spec-, and Spec+ were 98.48% (95% CI: 95.90-99.51%), 99.55% (95% CI: 97.12-99.97%), 95.04% (95% CI: 89.65-97.81%), and 97.39% (93.69-99.03%), respectively. A high classification rate (93.41%; 95% CI: 89.14-96.24%) and almost perfect agreement (Cohen's kappa: 0.903, 95% CI: 0.86-0.95) were achieved. Conclusions: The guiding system can rapidly and accurately classify the types of AP shoulder radiography, thereby guiding the adjustment of patient positioning. This will facilitate the rapid obtainment of reliable CSA radiography to measure the CSA on proper AP radiographs.

Enhancing prediction of supraspinatus/infraspinatus tendon complex injuries through integration of deep visual features and clinical information: a multicenter two-round assessment study.

OBJECTIVE: Develop and evaluate an ensemble clinical machine learning-deep learning (CML-DL) model integrating deep visual features and clinical data to improve the prediction of supraspinatus/infraspinatus tendon complex (SITC) injuries. METHODS: Patients with suspected SITC injuries were retrospectively recruited from two hospitals, with clinical data and shoulder x-ray radiographs collected. An ensemble CML-DL model was developed for diagnosing normal or insignificant rotator cuff abnormality (NIRCA) and significant rotator cuff tear (SRCT). All patients suspected with SRCT were confirmed by arthroscopy examination. The model's performance was evaluated using sensitivity, specificity, accuracy, and area under the curve (AUC) metrics, and a two-round assessment was conducted to authenticate its clinical applicability. RESULTS: A total of 974 patients were divided into three cohorts: the training cohort (n = 828), the internal validation cohort (n = 89), and the external validation cohort (n = 57). The CML-DL model, which integrates clinical and deep visual features, demonstrated superior performance compared to individual models of either type. The model's sensitivity, specificity, accuracy, and area under curve (95% confidence interval) were 0.880, 0.812, 0.836, and 0.902 (0.858-0.947), respectively. The CML-DL model exhibited higher sensitivity and specificity compared to or on par with the physicians in all validation cohorts. Furthermore, the assistance of the ensemble CML-DL model resulted in a significant improvement in sensitivity for junior physicians in all validation cohorts, without any reduction in specificity. CONCLUSIONS: The ensembled CML-DL model provides a solution to help physicians improve the diagnosis performance of SITC injury, especially for junior physicians with limited expertise. CRITICAL RELEVANCE STATEMENT: The ensembled clinical machine learning-deep learning (CML-DL) model integrating deep visual features and clinical data provides a superior performance in the diagnosis of supraspinatus/infraspinatus tendon complex (SITC) injuries, particularly for junior physicians with limited expertise. KEY POINTS: 1. Integrating clinical and deep visual features improves diagnosing SITC injuries. 2. Ensemble CML-DL model validated for clinical use in two-round assessment. 3. Ensemble model boosts sensitivity in SITC injury diagnosis for junior physicians.

Deep learning for automated measurement of CSA related acromion morphological parameters on anteroposterior radiographs.

BACKGROUND: The Critical Shoulder Angle Related Acromion Morphological Parameter (CSA- RAMP) is a valuable tool in the analyzing the etiology of the rotator cuff tears (RCTs). However, its clinical application has been limited by the time-consuming and prone to inter- and intra-user variability of the measurement process. OBJECTIVES: To develop and validate a deep learning algorithm for fully automated assessment of shoulder anteroposterior radiographs associated with RCTs and calculation of CSA-RAMP. METHODS: Retrospective analysis was conducted on radiographs obtained from computed tomography (CT) scans and X-rays performed between 2018 and 2020 at our institution. The development of the system involved the utilization of digitally reconstructed radiographs (DRRs) generated from each CT scan. The system's performance was evaluated by comparing it with manual and semiautomated measurements on two separate test datasets: dataset I (DRRs) and dataset II (X-rays). Standard metrics, including mean average precision (AP), were utilized to assess the segmentation performance. Additionally, the consistency among fully automated, semiautomated, and manual measurements was comprehensively evaluated using the Pearson correlation coefficient and Bland-Altman analysis. RESULTS: A total of 1080 DRRs generated from 120 consecutive CT scans and 159 X-ray films were included in the study. The algorithm demonstrated excellent segmentation performance, with a mean AP of 57.67 and an AP50 of 94.31. Strong inter-group correlations were observed for all CSA-RAMP measurements in both test datasets I (automated versus manual, automated versus semiautomated, and semiautomated versus manual; r = [0.990---0.997], P < 0.001) and dataset II (r = [0.984---0.995], P < 0.001). Bland-Altman analysis revealed low bias for all CSA-RAMP measurements in both test datasets I and II, except for CD (with a maximum bias of 2.49%). CONCLUSIONS: We have successfully developed a fully automated algorithm capable of rapidly and accurately measuring CSA-RAMP on shoulder anteroposterior radiographs. A consistent automated CSA- RAMP measurement system may accelerate powerful and precise studies of disease biology in future large cohorts of RCTs patients.

Machine learning model successfully identifies important clinical features for predicting outpatients with rotator cuff tears.

PURPOSE: The aim of this study is to develop a machine learning model to identify important clinical features related to rotator cuff tears (RCTs) using explainable artificial intelligence (XAI) for efficiently predicting outpatients with RCTs. METHODS: A retrospective review of a local clinical registry dataset was performed to include patients with shoulder pain and dysfunction who underwent questionnaires and physical examinations between 2019 and 2022. RCTs were diagnosed by shoulder arthroscopy. Six machine-learning algorithms (Stacking, Gradient Boosting Machine, Bagging, Random Forest, Extreme Gradient Boost (XGBoost), and Adaptive Boosting) were developed for the prediction. The performance of the models was assessed by the area under the receiver operating characteristic curve (AUC), Brier scores, and Decision curve. The interpretability of the predicted outcomes was evaluated using Shapley additive explanation (SHAP) values. RESULTS: A total of 1684 patients who completed questionnaires and clinical tests were included, and 417 patients with RCTs underwent shoulder arthroscopy. In six machining learning algorithms for predicting RCTs, the accuracy, AUC values, and Brier scores were in the range of 0.81-0.86, 0.75-0.92, and 0.15-0.19, respectively. The XGBoost model showed superior performance with accuracy, AUC, and Brier scores of 0.85(95% confidence interval, 0.82-0.87), 0.92 (95% confidence interval,0.90-0.94), and 0.15 (95% confidence interval,0.14-0.16), respectively. The Shapley plot showed the impact of the clinical features on predicting RCTs. The most important variables were Jobe test, Bear hug test, and age for prediction, with mean SHAP values of 1.458, 0.950, and 0.790, respectively. CONCLUSION: The machine learning model successfully identified important clinical variables for predicting patients with RCTs. In addition, the best algorithm was also integrated into a digital application to provide predictions in outpatient settings. This tool may assist patients in reducing their pain experience and providing prompt treatments. LEVEL OF EVIDENCE: Level III.

The Application of H-Loop in Arthroscopic Knotless Double-Row Rotator Cuff Repairs.

OBJECTIVE: To determine the functional outcomes after a novel method of H-loop knotless double-row technique in patients with rotator cuff tears. METHOD: From June 2020 to September 2020, a total of six patients (five women, one man) with arthroscopic rotator cuff repair using the H-loop knotless double-row technique were enrolled in our study. The average age is 54 years (range: 50-61 years). The preoperative and final follow-up clinical outcome were evaluated using the American Shoulder and Elbow Surgeons (ASES) score, visual analog scale (VAS), University of California Los Angeles (UCLA) score, and Constant-Murley score. The active shoulder range of motion (ROM) was also collected preoperatively and postoperatively at the final follow-up (forward flexion and abduction). Accordingly, intraoperative and postoperative complications were observed as well. RESULT: There were six patients that underwent arthroscopic rotator cuff repair using the H-loop knotless double-row technique. The average follow-up period was 7.52 ± 0.70 months. The VAS, UCLA, ASES, and Constant-Murley scores improved from 5 ± 2.45, 15.67 ± 3.44, 47.67 ± 17.41 and 49.17 ± 8.98 preoperatively, to 0.83 ± 0.75, 36.27 ± 3.83, 91.67 ± 10.76 and 85.83 ± 4.31 at the final follow-up, with statistical significances of P = 0.009, P < 0.001, P = 0.006, and P = 0.001, respectively. Meanwhile, the active shoulder ROM (forward flexion and abduction) improved from 135.00 ± 46.80 and 125 ± 56.48 preoperatively, to 173.67 ± 4.13 and 172 ± 3.27 at final follow-up, respectively (P = 0.082, P = 0.088). During the follow-up, there were no postoperative complications such as wound-site infection, nerve or vessel damage, subcutaneous hematoma, and suture anchor problems. CONCLUSION: With the benefit of reducing the possibility of strangulation and blood supply affection for the rotator cuff, The H-loop knotless double row technique may be an alternative method to significantly improve subjective functional outcomes and increase the healing rate of medium-sized rotator cuff tears with degeneration issues and poor tissue quality.

Young's Modulus of Bilateral Infraspinatus Tendon Measured in Different Postures by Shear Wave Elastography Before and After Exercise.

OBJECTIVE: To investigate the Young's modulus value of infraspinatus tendons using shear wave elastography (SWE) technique in normal adults, and to analyze the influence of gender, postures, exercise, and dominant side on Young's modulus of infraspinatus tendons. METHODS: This is a prospective cross-sectional study. From January 2019 to July 2020, 14 healthy subjects were identified, including seven males and seven females aged between 24 to 34, with a mean age of 27.67 ± 3.08 years. The Young's modulus of their infraspinatus tendons was measured by two operators using SWE in neutral and maximum external rotation positions of both sides before exercise and the dominant side after exercise. The Young's modulus values in different sexes, different postures, before vs after exercise, and dominant vs non-dominant side were statistically analyzed. RESULTS: All 14 subjects completed the data collection process. The mean Young's modulus values of infraspinatus tendon for dominant sides in neutral position were 33.04 ± 3.01 kPa for males and 28.76 ± 3.09 kPa for females. And for non-dominant sides in the neutral position, the values were 33.02 ± 2.38 kPa for males and 28.86 ± 2.47 kPa for females. In the maximum external rotation position, the values for dominant sides were 50.19 ± 4.86 kPa for males and 42.79 ± 4.44 kPa for females, and for non-dominant sides were 50.95 ± 3.24 kPa for males and 42.42 ± 3.66 kPa for females. After exercise, the mean Young's modulus values of infraspinatus tendon for dominant sides in neutral position were 54.56 ± 3.76 kPa for males and 46.66 ± 5.99 kPa for females. And for the maximum external rotation position, the values were 59.13 ± 3.78 kPa for males and 54.49 ± 5.67 kPa for females. The Young's modulus of infraspinatus tendon in the neutral and maximum external rotation positions showed statistically significant differences in males and females, as well as before and after exercise (P < 0.05). However, the difference in Young's modulus between the dominant and non-dominant sides was not statistically significant (P > 0.05). Intergroup reliability between both operators was excellent (ICC > 0.85). CONCLUSION: There are gender-related differences and post-exercise increase in Young's modulus, yet such a difference cannot be witnessed between the dominant and non-dominant sides.

Arthroscopic Superior Capsule Reconstruction and Rotator Cuff Repair to Restore Static and Dynamic Stability of the Shoulder.

OBJECTIVE: Treatment of massive irreparable rotator cuff tears (RCT) has shown limited clinical success and a variety of subsequent complications. Superior capsule reconstruction (SCR) has been proved to reestablish superior stability but does not restore the dynamic force or shoulder kinematics. There are numerous reports of the short-term failure of SCR grafts at the glenoid side, which relate to the non-biological healing of grafts. To restore both dynamic and static stability and to provide biologic augmentation, an integrated procedure for massive irreparable RCT using an Achilles tendon-bone allograft (ATBA) was developed. METHOD: This was a retrospect study completed between October 2019 and April 2020. A 71-year-old woman with massive and irreparable rotator cuff tears was enrolled in our study. The ATBA was folded into a double-layer structure. The superior layer (proximal portion) served as a bridge patch to dynamic the glenohumeral joint, while the inferior layer (distal portion) served as the superior capsule to restore static stability of glenohumeral joint. To enhance biologic healing on the glenoid side, we fixed the calcaneus of the graft on the superior-posterior side of the superior glenoid rim. The recovery of shoulder function (including strength, range of motion, acromiohumeral interval, and fatty infiltration) was assessed at 6 months postoperation. RESULT: At 6-month follow-up, the patient's strength had improved significantly (from abduction of grade 3 preoperatively to grade 4 at 6 months). Radiographic analysis showed an increase in the acromiohumeral interval from 3 to 7 mm. Magnetic resonance imaging revealed an intact graft, with the thickness of the ligament part maintained (at 6-7 mm). Most importantly, recovery of atrophy and fatty infiltration of the supraspinatus were observed. No graft tears were observed on the glenoid side. CONCLUSION: This technique could provide a preferable treatment option by restoring shoulder kinematics and augmentating biological healing for patients with massive irreparable RCT.

Validation of a Mobile Version of the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form: An Observational Randomized Crossover Trial.

BACKGROUND: The American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) questionnaire is an effective tool for evaluating shoulder joint function. The development and usage of a mobile version of the ASES questionnaire has the potential to save time, money, and effort. OBJECTIVE: The aim of this study is to assess the equivalence between the paper and mobile versions of the ASES questionnaire and their acceptability among patients. METHODS: The paper and mobile versions of the ASES questionnaire were used to evaluate the shoulder joint function of 50 patients with shoulder pain. This study included patients from the shoulder clinic of Sun Yat-sen Memorial Hospital. The intraclass correlation coefficient (ICC) and Bland-Altman method were used to evaluate the agreement (reliability) of the scores obtained by the two methods (paper versus mobile). RESULTS: Of the 50 patients recruited from March 2018 to May 2019, 46 (92%) completed the study. There was a high agreement between the paper and mobile versions of the ASES questionnaire (ICC=0.979, 95% CI 0.943-0.987; P<.001). The mean difference between the scores of the mobile and paper versions was 1.0, and only 1/46 (2%) had a difference greater than the minimal clinically important difference of 12 points. About 75% of patients preferred the mobile version to the paper version. CONCLUSIONS: Our study shows that the mobile version of the ASES questionnaire is comparable to the paper version, and has a higher patient preference. This could prove to be a useful tool for epidemiological studies and patient follow-up over longer periods of time.

Preparation of Multiwall Carbon Nanotubes Embedded Electroconductive Multi-Microchannel Scaffolds for Neuron Growth under Electrical Stimulation.

OBJECTIVES: To prepare the conductive MWCNT (multiwall carbon nanotube)-agarose scaffolds with multi-microchannel for neuron growth under electrical stimulation. METHODS: The scaffolds were produced by gradient freeze and lyophilization methods. The synthesized materials were characterized by SEM and near-infrared spectroscopy, and their microstructure, swelling-deswelling, conductivity, biocompatibility, and shape memory behavior were measured. A three-dimensional culture model by implanting cells into scaffolds was built, and the behaviors of RSC96 cells on scaffolds under electrical stimulation were evaluated. RESULTS: The addition of MWCNT did not affect the pore composition ratio and shape memory of agarose scaffolds, but 0.025% wt MWCNT in scaffolds improved the swelling ratio and water retention at the swelling equilibrium state. Though MWCNTs in high concentration had slight effect on proliferation of RSC96 cells and PC12 cells, there was no difference that the expressions of neurofilament of RSC96 cells on scaffolds with MWCNTs of different concentration. RSC96 cells arranged better along the longitudinal axis of scaffolds and showed better adhesion on both 0.025% MWCNT-agarose scaffolds and 0.05% MWCNT-agarose scaffolds compared to other scaffolds. CONCLUSIONS: Agarose scaffolds with MWCNTs possessed promising applicable prospect in peripheral nerve defects.

Bifocal or Trifocal (Double-Level) Bone Transport Using Unilateral Rail System in the Treatment of Large Tibial Defects Caused by Infection: A Retrospective Study.

OBJECTIVE: The aim of this study is to assess the clinical results of bifocal or trifocal bone transport using unilateral rail system in the treatment of large tibial defects caused by infection. METHODS: There were a total of 37 eligible patients with an average age of 40.11 ± 10.32 years (range, 18-57 years; 28 males and nine females) with large tibial defects due to infection who were admitted to our hospital from June 2006 to June 2016. Among the patients, 21 underwent bifocal bone transport (BF group), and the remaining 16 were treated with trifocal bone transport (TF group). The demographic data (age, sex, interval duration before bone transport, previous operation time), intraoperative outcomes (size and location of the defect, size of soft tissue defect), postoperative variables (lengthening speed, external fixation index, duration of regenerate consolidation and docking union), postoperative bone and functional outcomes evaluated by Association for the Study and Application of the Method of Ilizarov (ASAMI) scoring system, and postoperative complications evaluated by Paley classification (muscle contraction, axial deviation, delayed consolidation, pin problems, repeated fracture, joint stiffness and others) of the two groups were recorded and compared at a minimum follow-up of 24 months. RESULTS: The mean duration of follow-up after removal of fixator was 29.49 ± 4.34 months (range, 24-38 months). There was no statistically significant difference in the demographic data, intraoperative outcomes including size and location of the defect, size of soft tissue defect, as well as postoperative complications. However, postoperative functional result in the TF group were superior to those in the BF group at a minimum follow-up of 24 months, and lengthening speed, external fixation index (EFI), duration of regenerate consolidation and docking union were significantly reduced in the TF group when compared with the BF group. CONCLUSIONS: Treatment of large tibial defects caused by infection with trifocal bone transport using unilateral rail system could significantly improve postoperative functional recovery and reduce duration of regenerate consolidation and docking union. The present study provides novel insight for the treatment of large tibial defects caused by infection.

Outcomes of revision neurolysis of the ulnar nerve and ulnar groove plasty for persistent and recurrent cubital tunnel syndrome-A retrospective study of 21 cases.

BACKGROUND: Patients undergoing revision surgical treatment of the ulnar nerve at the elbow for cubital tunnel syndrome (CuTS) will have worse results compared to patients successfully treated with primary surgery. OBJECTIVE: The purpose of this study is to evaluated clinical outcomes of revision neurolysis and ulnar groove plasty for recurrent and persistent cubital tunnel syndrome after failed surgical treatment. METHODS: This retrospective investigation included patients presented with recurrent and persistent CuTS who were treated surgically with combination of revision neurolysis and ulnar groove plasty at a single institution from May 2006 to Oct 2016 with postoperative follow-up more than 24 months. Demographic data of all patients including age, sex, months to revision surgery, presenting symptoms after index surgery, previous surgical procedure and intraoperative findings were all recorded and pre-operative and post-operative data were compared. McGowen grading was used to evaluated functional impairment before and after revision surgery. RESULTS: There were 28 patients were identified with recurrent and persistent CuTS after primary surgery and 21 patients (75%) were completed in this study with an average age was 56 years, mean duration of symptoms was 17.24 months, and mean postoperative follow-up was 35.38 months. 17 patients had McGowan stage III and 4 had stage II preoperatively. The most common cause of recurrent and persistent CuTS was perineural fibrosis with or without kink which accounts for 86.36% according to intraoperative findings. McGowan grading improved after revision neurolysis and ulnar groove plasty is 80.95%. Improvement of Visual Analogue Scale (VAS) and 2-point discrimination test were 81.25% and 85.71%, respectively. Patients satisfaction after revision neurolysis and ulnar groove plasty was 95.24%. CONCLUSION: The favorable results of this study demonstrated that revision neurolysis and ulnar groove plasty as the treatment of choice for recurrent or persistent cubital tunnel syndrome.

IL-21 gene rs6822844 polymorphism and rheumatoid arthritis susceptibility.

Interleukin-21 (IL-21) is a cytokine that plays a crucial role in pathogenesis and activity of the rheumatoid arthritis (RA). Meanwhile, genetic polymorphisms in the IL-21 gene may alter its expression. Previous studies have reported conflicting results assessing the association between the IL-21 rs6822844 G/T polymorphism and RA risk. Thus, it's necessary to perform a meta-analysis to definite above relationship. PubMed database was searched for all papers published until October 20, 2019. Nine case-control studies with 9998 cases and 10742 controls were retrieved based on the search criteria at last. Odds ratio (95% confidence interval) was used to calculate the strength of this association. Publication bias was detected using both Begg's and Egger's tests. Overall, the IL-21 rs6822844 G/T polymorphism was found to be significantly associated with decreased RA risk (e.g. T-allele versus G-allele: OR = 0.81, 95% CI = 0.72-0.91, P < 0.001). In addition, decreased RA risk was also detected both in Asians (eg: TT+TG versus GG: OR = 0.42, 95% CI = 0.31-0.56, P < 0.001) and Caucasians (eg: TT+TG versus GG: OR = 0.85, 95% CI = 0.80-0.91, P < 0.001). A similar trend in association was found in the source of the control and genotype method subgroups. Furthermore, subgroup analysis of rheumatoid factor status revealed a protective relationship between the IL-21 rs6822844 G/T polymorphism and RF+/RF- RA risk. A similar relationship was noted in the anti-citrullinated protein antibody status subgroup. The results of the present study suggest that the IL-21 rs6822844 G/T polymorphism was significantly associated with decreased RA susceptibility.

Precise Resection of Macrodactyly Under Assistance of Three-Dimensional Reconstruction Technology: A Case Report.

Macrodactyly of the foot is an extremely rare congenital malformation characterized by an increase in the size of all the elements or structures of a digit or digits. Most sources indicate that macrodactyly affects the hand more often than the foot. This rare medical condition usually requires surgical intervention with a precise preoperative plan and postoperative rehabilitation. We present a case of macrodactyly of the right foot in which surgical reduction of the foot under assistance of 3-dimensional image technology was performed with satisfying cosmetic and functional outcomes.

Application of custom anatomy-based nerve conduits on rabbit sciatic nerve defects: in vitro and in vivo evaluations.

The intermingling of regenerated nerve fibers inside nerve grafts is the main reason for mismatched nerve fibers. This is one of the key factors affecting limb function recovery after nerve injury. Previous research has shown that the accuracy of axon regeneration can be improved by a bionic structural implant. To this aim, iodine and freeze-drying high-resolution micro-computed tomography was performed to visualize the 3D topography of the New Zealand rabbit sciatic nerve (25 mm). A series of 1-, 2-, 3-, and 4-custom anatomy-based nerve conduits (CANCs) were fabricated based on the anatomical structure of the nerve fascicle. The match index, luminal surface, and mechanical properties of CANCs were evaluated before implanting in a 10-mm gap of the sciatic nerve. Recovery was evaluated by histomorphometric analyses, electrophysiological study, gastrocnemius muscle weight recovery ratio, and behavioral assessments at 12 and 24 weeks postoperatively. The accuracy of nerve regeneration was determined by changes in fluorescence-labeled profile number during simultaneous retrograde tracing. Our results showed that the optimal preprocessing condition for high-resolution micro-computed tomography visualization was treatment of the sciatic nerve with 40% Lugol's solution for 3 days followed by lyophilization for 2 days. In vitro experiments demonstrated that the match index was highest in the 3-CANC group, followed by the 2-, 1-, and 4-CANC groups. The luminal surface was lowest in the 1-CANC group. Mechanical properties (transverse compressive and bending properties) were higher in the 3- and 4-CANC groups than in the 1-CANC group. In vivo experiments demonstrated that the recovery (morphology of regenerated fibers, compound muscle action potential, gastrocnemius muscle weight recovery ratio, pain-related autotomy behaviors, and range of motion) in the 3-CANC group was superior to the other CANC groups, and achieved the same therapeutic effect as the autograft. The simultaneous retrograde tracing results showed that the percentages of double-labeled profiles of the 2-, 3-, and 4-CANC groups were comparatively lower than that of the 1-CANC group, which indicates that regenerated nerve fascicles were less intermingled in the 2-, 3-, and 4-CANC groups. These findings demonstrate that the visualization of the rabbit sciatic nerve can be achieved by iodine and freeze-drying high-resolution micro-computed tomography, and that this method can be used to design CANCs with different channels that are based on the anatomical structure of the nerve. Compared with the 1-CANC, 3-CANC had a higher match index and luminal surface, and improved the accuracy of nerve regeneration by limiting the intermingling of the regenerated fascicles. All procedures were approved by the Animal Care and Use Committee, Xinjiang Medical University, China on April 4, 2017 (ethics approval No. IACUC20170315-02).

Clinical outcomes of contralateral 7th cervical nerve transfer in the treatment of total brachial plexus root avulsion in Xinjiang Autonomous Region / 中华显微外科杂志

Objective To evaluate the long-term functional recovery after contralateral 7th cervical nerve(C7) transfer with brachial plexus root avulsion and the effect on the contralateral limbs after operation. Methods A total of 83 patients with injory of brachial plexus avulsion were underwent contralateral C7 transfer from September, 2004 to December, 2014.Among them, contralateral C7 were transferred to the median nerve in 33 cases, to radial nerve in 14 cases, to musculocutaneous nerve in 22 cases, and simultaneous transfer to median and musculocutaneous nerve in 14 cases.The followed-up contents included recovery of muscular strength and sensory innervated by the recipient nerve, bilateral limbs synergistic activity and the effect on the contralateral limbs after the surgery. Results All 83 cases were successfully followed-up for 3.2-6.2 years (average, 4.5 years), and found no significant effect on function of the contralateral limbs. In the group of C7 transferred to the median nerve group, 10 cases had muscle strength recov鄄ered≥M3, and 26 cases had sensory recovered≥S3; In the group of C7 transferred to the radial nerve, 6 cases had muscle strength recovered≥M3, and 9 cases had sensory recovered ≥S3; In the group of C7 transferred to the muscu鄄locutaneous nerve, 12 cases had muscle strength recovered≥M3, and 17 cases had sensory recovered≥S3.In the group of C7 simultaneous transferred to the median and musculocutaneous nerve, 6 cases had muscle strength of wrist and digital flexion recovered≥M3, 5 cases had elbow flexion recovered≥M3, 9 and 10 cases had sensory of innervated area and lateral forearm region recovered≥S3, respectively. Conclusion Contralateral C7 transfer is an ideal procedure for the treatment of total brachial plexus root avulsion with definitive clinical outcomes.

Clinical outcomes of contralateral 7th cervical nerve transfer in the treatment of total brachial plexus root avulsion in Xinjiang Autonomous Region / 中华显微外科杂志

Objective@#To evaluate the long-term functional recovery after contralateral 7th cervical nerve(C7) transfer with brachial plexus root avulsion and the effect on the contralateral limbs after operation.@*Methods@#A total of 83 patients with injory of brachial plexus avulsion were underwent contralateral C7 transfer from September, 2004 to December, 2014. Among them, contralateral C7 were transferred to the median nerve in 33 cases, to radial nerve in 14 cases, to musculocutaneous nerve in 22 cases, and simultaneous transfer to median and musculocutaneous nerve in 14 cases. The followed-up contents included recovery of muscular strength and sensory innervated by the recipient nerve, bilateral limbs synergistic activity and the effect on the contralateral limbs after the surgery.@*Results@#All 83 cases were successfully followed-up for 3.2-6.2 years (average, 4.5 years), and found no significant effect on function of the contralateral limbs. In the group of C7 transferred to the median nerve group, 10 cases had muscle strength recovered≥M3, and 26 cases had sensory recovered≥S3; In the group of C7 transferred to the radial nerve, 6 cases had muscle strength recovered≥M3, and 9 cases had sensory recovered ≥S3; In the group of C7 transferred to the musculocutaneous nerve, 12 cases had muscle strength recovered≥M3, and 17 cases had sensory recovered≥S3. In the group of C7 simultaneous transferred to the median and musculocutaneous nerve, 6 cases had muscle strength of wrist and digital flexion recovered≥M3, 5 cases had elbow flexion recovered≥M3, 9 and 10 cases had sensory of innervated area and lateral forearm region recovered≥S3, respectively.@*Conclusion@#Contralateral C7 transfer is an ideal procedure for the treatment of total brachial plexus root avulsion with definitive clinical outcomes.

Application of the bionic multi-channel nerve conduit in the rabbit sciatic nerve defect by reducing mismatch of regenerated nerve fibers / 中华显微外科杂志

To investigate the role of the bionic multi-channel nerve conduit by reducing mis-match of regenerated nerve fibers in the rabbit sciatic nerve defect. Methods The experiment was conducted from July, 2017 to February, 2019. A total of 55 New Zealand white rabbits were randomly divided into two groups (First group, n=30 and Second group, n=25).There were 5 subgroups (n=6) in the first group, which were autograft and cus-tom-anatomic nerve conduits (CANC) with different channel (1-CANC, 2-CANC, 3-CANC, 4-CANC) that implanted to repair the rabbit sciatic nerve defect (10 mm). The electrophysiological, triceps muscle wet weight recovery rate, histological study and ankle index analysis were used to evaluate the treatment of each group at 12 and 24 weeks postoperatively. There were 5 subgroups (n=5) in the second group. The simultaneous retrograde tracing method was applied to compare with the number of mismatched nerve fibers at 24 weeks postoperatively. All data were recorded and analyzed by One-way ANOVA method, the Turkey’s method was used to compare the differences between each subgroup. The difference was considered to be statistically significant if P＜0.05. Results The autograft group showed the best recovery in the electrophysiology, histology study and ankle index at 12 and 24 weeks postoperatively (P＜0.05).Histology results showed that the same number of myelinated nerve fibers in all CANC group (P＞0.05), but di-ameters of nerve fiber and myelin thickness were higher in 2-CANC and 3-CANC [(10.67±0.56) μm,(10.65±0.53) μm, respectively] compared with 1-CANC and 4-CANC groups [(8.43±0.63) μm, (9.03±0.55) μm, respectively].The differ-ences were similar in electrophysiological, wet weight recovery rate of triceps muscle, histological study and ankle index analysis.Simultaneous retrograde tracing showed that the autograft group had highest total number of labeled profiles, but no significant difference of the total number of labeled profile was showed among the CANC groups. However, the 1-CANC group[(7.1±2.4) %] showed highest percentage of the FB-NY-neurons than other CANC groups[(2.7±1.9)% in 2-CANC, (2.5±2.3) % in 3-CANC, and (2.2±1.2)% in 4-CANC](P＜0.05). Conclusion The autograft group showed the best results among all groups.Compared with the 1-CANC group, the 2-CANC and 3-CANC group obtained more mature regenerated nerve fibers and with a fewer mismatch rate.Moreover, that did not affect the number of regenerated fibers.

The psychological impact of external fixation using the Ilizarov or Orthofix LRS method to treat tibial osteomyelitis with a bone defect.

OBJECTIVE: To examine the psychological impact of external fixation for a tibial bone defect due to osteomyelitis, and to compare the Orthofix limb reconstruction system (LRS) with the Ilizarov external fixator. MATERIALS AND METHODS: The SCL-90-R questionnaire was administered at four different time points (before surgery, while patients wore the external fixation device, when the device was removed, and two to three months after). The scores at the four time points were compared, as were the two different methods of external fixation (Orthofix LRS vs. Ilizarov). RESULTS: The patients experienced a significant adverse impact on their mental health, with the worst outcomes at Time 2 (while wearing the external fixator), but with some negative effects still present even several months after removal of the fixation device. Although the Orthofix LRS and Ilizarov groups showed similar mental health scores at Time 1 (preoperatively) and Time 3 (upon removal of the fixation device), the Orthofix LRS was associated with better scores, specifically in the Hostility (Time 2), Phobic Anxiety (Time 2), Psychoticism (Times 2 and 4), and Other (Time 2) sub-scores, as well as the total score (Times 2 and 4). CONCLUSIONS: Although both Ilizarov and Orthofix LRS fixation resolved the bone defects, external fixation had a negative impact on the patients' mental health, which persisted even after removal of the devices. Although both methods led to negative effects on the patients' mental, the impact of the Orthofix LRS was less severe.

NRSN2 promotes osteosarcoma cell proliferation and growth through PI3K/Akt/MTOR and Wnt/ß-catenin signaling.

Osteosarcoma is the most common bone cancer in children and adults. However, its pathogenesis, especially molecular mechanisms remain elusive. In current study, we screened GEO Database and found a poorly studied protein Neurensin-2 (NRSN2), which is highly expressed in osteosarcoma tissues. Neurensin-2 (NRSN2) is a small neuronal membrane protein and localized in small vesicles in neural cells, previous study found that it has been implicated in hepatocellular carcinoma (HCC) and non-small cell lung cancer (NSCLC). We here report that the expression of NRSN2 is more commonlyelevated in 18 fresh osteosarcoma tissues. Furthermore, both loss- and gain-functions assays revealed that NRSN2 could promote osteosarcoma cell proliferation and growth both in vitro and in vivo. In addition, we further found that those effects on osteosarcoma by NRSN2 are associated with the dysregulated PI3K/AKT/mTOR signaling and Wnt/ß-catenin signaling. In conclusion, our study found a novel oncogenic protein, NRSN2, which promotes osteosarcoma cell proliferation and as a membrane protein, NRSN2 also could be a potential treatment target for osteosarcoma.

Post-traumatic osteomyelitis treat with trifocal bone transportations: a case report and review of lecture / 中华显微外科杂志

Objective To explore the possibility of reduce the treatment cycle of post-traumatic osteomyelitis patients treat with bone transportations. Methods In February, 2017, a patient was diagnosis as left tibial os-teomyelitis with soft tissue defects and treated. Before start trifocal bone transportation with Orthofix external fixator, we did preoperative practice with computer and model. Except this case we also had some article review in this report. Results This case not only finished 12.5 cm bone transportation in 45 days but also treated soft tissue defect before bone transportations. In this method we save almost 2/3 time to compare with monofocal bone transportations, and frame time were also faster than previous method. But because of some mishaps when we follow-up, the gap was occurred in docking side after 140 days follow-up that may need bone transplants. After 140 days of operation, the gap was disap-peared. Conclusion A new type bone transportations in this study and it may reduce treatment time of osteomyelitis.