Arthroscopic Bone Grafting and Robot-assisted Fixation for Scaphoid Nonunion.

OBJECTIVES: Scaphoid nonunion remains a challenging problem to manage with no general consensus on its treatment recommendations. We propose a novel minimally invasive (MIS) technique of arthroscopic bone grafting (ABG) with robot-assisted fixation for the treatment of scaphoid nonunions. METHODS: Patients with radiographically proven scaphoid nonunion treated by this novel surgical technique were included. Following arthroscopic debridement and iliac crest bone grafting, the scaphoid was fixed percutaneously using either multiple Kirschner (K)-wires or a headless compression screw using a robotic navigation system. RESULTS: Six male patients with an average age of 29.2 years were enrolled. Four patients had scaphoid waist fractures, and the other two were proximal pole fractures. During wrist arthroscopy, punctate bleeding of the proximal scaphoid fragment was observed in four out of the six patients. Half of the patients were fixed using a headless compression screw and the other half using multiple K-wires. All the guidewires were placed with a single-attempt using the robotic navigation system. Postoperatively, all the scaphoid fractures had complete radiographic union by 16 weeks. At a mean follow-up of 18.3 months, there were significant improvements in wrist range of motion, grip strength, and patient-rated outcomes. No intraoperative or early postoperative complications were encountered in any of our patients. CONCLUSION: Arthroscopic bone grafting with robot-assisted fixation is a feasible and promising therapeutic option for scaphoid nonunions, regardless of the vascularity of the proximal pole fragment. This novel technique allows for anatomic restoration of the scaphoid alignment and accurate, targeted placement of implants into the scaphoid nonunion site within a single-attempt using a robotic navigation system.

A comparative cadaveric study for percutaneous scaphoid fixation: robotic vs freehand.

PURPOSES: To compare the robotic-assisted and the traditional freehand percutaneous scaphoid fixation in number of guidewire attempts, duration of fluoroscopy time, amount of radiation dose, and screw centrality. METHODS: Twenty cadaveric specimens were randomized into either the robotic or freehand group. The scaphoids in both groups were fixed by either the same attending or resident from our hand surgery department. The operation duration, amount of radiation from intraoperative fluoroscopy, total fluoroscopy time, and the number of guidewire attempts were documented and compared. Postoperatively, all the specimens had a computed tomography (CT) scan performed, and the difference in the final position of the screw and the central axis of the scaphoid was examined. RESULTS: In the robotic group, all the guide wires were satisfactorily positioned within a single attempt, while the median number of attempts in the traditional freehand group was 18 (quaternion 14-65). This also meant that the surgeon in the robotic group experienced significantly lower radiation exposure dose and time as compared to the freehand group. There were no significant differences in the final screw position as compared to the central axis of the scaphoid in both groups. Although there was no difference in surgeon performance in the robotic group, the operative time for the attending was significantly lower as compared to the resident in the freehand group. CONCLUSION: Robotic-assisted surgery for scaphoid fracture fixation is superior to the traditional freehand method as it facilitates accurate screw placement with lower radiation exposure and fewer guide wire attempts.

Quantitative Analysis of Deformity in Digital Model of Congenital Radioulnar Synostosis.

OBJECTIVE: The deformity of congenital radioulnar synostosis is quite complicated and difficult. This study aims to find out the related factors of the "forearm rotation angle" (FR) which relate to the severity of congenital radioulnar synostosis (CRUS), and try to quantify the internal relations of each deformity and help to understand the reconstruction method in surgery treatment of this disease. METHODS: This study is case series research. We established 48 digital three-dimensional forearm bone models of 48 patients with congenital radioulnar synostosis classified as Cleary and Omer type 3. All the patients were treated at our institution from January 2010 to June 2016. In total, 10 independent deformities (the rotation angle of forearm; the internal rotation, radial, and dorsal angulation of radius and ulna; the relative length of osseous fusion at PRUJ; the relative dislocation distance of distal radioulnar joint; the relative area of proximal radial epiphysis) involved in the CRUS complex deformity were measured. Pearson correlation analysis for each deformity which was mentioned above was performed, and multivariate linear regression analysis was also performed with FR as the dependent variable and the other deformities as the influential factors. RESULTS: The "dorsal angle of radius" (DAR, 21.69° ± 21.55°) had the strongest correlation with the FR (79.72° ± 40.39°), the Pearson correlation coefficient was 0.601 (p < 0.01), the internal rotation angle of the radius (IRAR, 82.69° ± 54.98°) had a moderate correlation with FR, the Pearson correlation coefficient was 0.552 (p < 0.01). A forearm deformity equation was established: FR = 35.896 + 0.271 DAR + 0.989 IRAR. CONCLUSION: The dorsal angulation deformity of radius may be the most important deformity that effects the severity of CRUS and should be correct in the first place during reconstruction operation.

A Novel Mini-Invasive Technique of Arthroscopic-Assisted Reduction and Robot-Assisted Fixation for Trans-Scaphoid Perilunate Fracture Dislocations.

OBJECTIVE: Perilunate injuries are rare but devastating carpal injuries. The treatment of perilunate injuries remains challenging and contentious. This study aims to describe a novel mini-invasive surgical technique of arthroscopic-assisted reduction and robot-assisted fixation for the treatment of trans-scaphoid perilunate fracture dislocations (PLFDs). METHODS: We retrospectively reviewed patients with PLFDs after surgical treatment from February 2021 to March 2021. The patients underwent arthroscopic-assisted precise reduction and robot-assisted headless screw fixation. Times of guide wire placement were recorded intraoperatively. Periodic follow-up was performed until union of scaphoid fracture was confirmed. Range of motion of the wrist, grip strength, the Visual Analog Scale (VAS) score, the Mayo Wrist Score, the Quick Disabilities of Arm, Shoulder, and Hand (QuickDASH) score, the Patient-Rated Wrist Evaluation (PRWE), and osteoarthritis were evaluated at the final follow-up. RESULTS: Two male patients presenting with PLFDs with an average age of 24.5 years old (32 and 17 years) were included in this study. Intraoperatively, anatomic reduction of the scaphoid fracture was achieved under arthroscopic guidance. A robotic-assisted single-attempt guidewire insertion was performed for scaphoid fracture and lunotriquetral interval. The CT scans at 8 and 12 weeks showed the union of the scaphoid fracture. At final mean follow-up of 13.5 months, the extension, radial-ulnar deviation, and pronation-supination were consistent with the contralateral side in both patients. One patient experienced mild limited range of motion with the flexion 46° of the injured wrist compared with 81°of the contralateral wrist. The VAS score was 0 and 2. The grip strength was 32 and 26 kg compared with 24 and 42 kg of the contralateral wrist. The PRWE score was 13 and 10 and the QuickDASH score was 2 and 7. The Mayo Wrist Score was 100 and 65. No sign of osteoarthritis was found at the last follow-up. CONCLUSIONS: Arthroscopic-assisted reduction and robot-assisted fixation is a viable and promising alternative for the treatment of perilunate fracture dislocations. This technique allows precise reduction and accurate placement of the K-wires/screws into the carpal bones through the optimal biomechanical paths.

Aloe-emodin targets multiple signaling pathways by blocking ubiquitin-mediated degradation of DUSP1 in nasopharyngeal carcinoma cells.

Aloe-emodin (AE) has been shown to inhibit the proliferation of several cancer cell lines, including human nasopharyngeal carcinoma (NPC) cell lines. In this study, we confirmed that AE inhibited malignant biological behaviors, including cell viability, abnormal proliferation, apoptosis, and migration of NPC cells. Western blotting analysis revealed that AE upregulated the expression of DUSP1, an endogenous inhibitor of multiple cancer-associated signaling pathways, resulting in blockage of the extracellular signal-regulated kinase (ERK)-1/2, protein kinase B (AKT), and p38-mitogen activated protein kinase（p38-MAPK） signaling pathways in NPC cell lines. Moreover, the selective inhibitor of DUSP1, BCI-hydrochloride, partially reversed the AE-induced cytotoxicity and blocked the aforementioned signaling pathways in NPC cells. In addition, the binding between AE and DUSP1 was predicted via molecular docking analysis using AutoDock-Vina software and further verified via a microscale thermophoresis assay. The binding amino acid residues were adjacent to the predicted ubiquitination site (Lys192) of DUSP1. Immunoprecipitation with the ubiquitin antibody, ubiquitinated DUSP1 was shown to be upregulated by AE. Our findings revealed that AE can stabilize DUSP1 by blocking its ubiquitin-proteasome-mediated degradation and proposed an underlying mechanism by which AE-upregulated DUSP1 may potentially target multiple pathways in NPC cells.

Evaluation of a convolutional neural network to identify scaphoid fractures on radiographs.

This study aimed to develop and evaluate a convolutional neural network for identifying scaphoid fractures on radiographs. A dataset of 1918 wrist radiographs (600 patients) was taken from an orthopaedic referral centre between 2010 to 2020. A YOLOv3 and a MobileNetV3 convolutional neural network were trained for scaphoid detection and fracture classification, respectively. The diagnostic performance of the convolutional neural network was compared with the majority decision of four hand surgeons. The convolutional neural network achieved a sensitivity of 82% and specificity of 94%, with an area under the receiver operating characteristic of 92%, whereas the surgeons achieved a sensitivity of 76% and specificity of 96%. The comparison indicated that the convolutional neural network's performance was similar to the majority vote of surgeons. It further revealed that convolutional neural network could be used in identifying scaphoid fractures on radiographs reliably, and has potential to achieve the expert-level performance.Level of evidence: III.

Abnormal MRI signal intensity of the triangular fibrocartilage complex in asymptomatic wrists.

We investigated abnormal MRI findings of the triangular fibrocartilage complex in 154 asymptomatic volunteers (21-79 years). Except prevalence, we focused on the morphological features of abnormal signals in relation to age. The majority of full-thickness tears were located in the articular disc (63 participants). The incidence of disc perforation with characteristics of ulnar impaction syndrome increased significantly with age. Asymptomatic full-thickness tears of the ulnar attachment were found in ten participants (seven over 60 years old). The proximal and distal laminae of the ulnar attachment could not be differentiated in 36 participants. In conclusion, MRI is of limited value for the elderly in diagnosing triangular fibrocartilage disorders. For young subjects, MRI is still valuable, especially in diagnosing ulnar detachment, although the ability to distinguish between proximal and distal laminae remains questionable. Disc perforations in volunteers mimicked ulnar impaction syndrome, therefore age, clinical signs and other factors should also be considered in clinical diagnosis.Level of evidence: III.

[Comparison of screw implantation parameters between two approaches in capitolunate arthrodesis: an imaging analysis based on CT of the normal wrist].

Objective: To compare the parameters of screw implantation in capitolunate arthrodesis between the 2nd and 3rd metacarpal bones and via the distal dorsal capitate bone approach based on CT images of the normal wrist, and provide reference for the selection of surgical approaches and planning of screw insertion trajectory. Methods: CT data of 50 patients who met the criteria between February 2022 and April 2022 were selected as the study objects. There were 30 males and 20 females, and the age ranged from 18 to 69 years (mean, 37 years). The normal wrist alignment was conformed in all CT images. All CT data from the unilateral wrist of the patients was imported into Mimics Medical 20.0 software to construct a three-dimensional plane model, in which a virtual 3.5 mm screw was implanted between the 2nd and 3rd metacarpal bones and via the distal dorsal capitate bone approach. The angle between screw and coronal, sagittal, and transverse planes, the total length of the screw, the length of the screw in the lunate bone and the capitate bone were measured. The ratios of the length of the screw in capitate bone to the length of the long axis of the capitate bone, the length of the screw in lunate bone to the length of the long axis of the lunate bone, and the length of screw in lunate bone to the length of the screw in capitate bone were calculated. Assuming that the result of screw implantation between the 2nd and 3rd metacarpal bones was better than that via the distal dorsal capitate bone approach, the difference in length of the screw in the lunate bone between the two approaches was calculated, and the superiority test was performed. Results: Compared with the distal dorsal capitate bone approach, the total length of the screw increased, the length of the screw in the capitate bone decreased, and the length of the screw in the lunate bone increased, the angle between the screw and coronal plane decreased, the angles between screw and sagittal, transverse planes increased after the screw was implanted between the 2nd and 3rd metacarpal bones. And the ratio of the length of the screw in capitate bone to the length of the long axis of capitate bone decreased, the ratio of the length of the screw in lunate bone to the length of the long axis of lunate bone increased, and the ratio of the length of the screw in lunate bone to the length of the screw in capitate bone also increased. All the differences were significant ( P<0.05). The difference in the length of the screw in the lunate bone between the two approaches was 1.86 mm [95% CI (1.54, 2.18) mm], which was greater than the superiority margin (1.35 mm). The superiority hypothesis was supported. Conclusion: Compared with the distal dorsal capitate bone approach, the screws implanted between the the 2nd and 3rd metacarpal bones in the capitolunate arthrodesis are longer in lunate bone and more vertical to the articular surface of the capitolunate joint. Theoretically, the capitolunate joint are more firmly fixed.

CCR5 as a prognostic biomarker correlated with immune infiltrates in head and neck squamous cell carcinoma by bioinformatic study.

BACKGROUND: C-C chemokine receptor 5 (CCR5) has recently been recognized as an underlying therapeutic target for various malignancies. However, the association of CCR5 with prognosis in the head and neck squamous cell carcinoma (HNSC) patients and tumor-infiltrating lymphocytes (TILs) is unclear. METHODS: In the current experiment, methods such as the Tumor Immune Estimation Resource Analysis (TIMER), Gene Expression Profiling Interactive Analysis (GEPIA), UALCAN, and Kaplan-Meier plotter Analysis were used to comprehensively evaluate the expression of CCR5 in human various malignancies and the clinical prognosis in HNSC patients. Subsequently, we used the TIMER database and the TISIDB platform to investigate the correlation between CCR5 expression levels and immune cell infiltration in the HNSC tumor microenvironment. Furthermore, immunomodulatory and chemokine profiling were performed using the TISIDB platform to analyse the correlation between CCR5 expression levels and immunomodulation in HNSC patients. RESULTS: We found that CCR5 expression in HNSC tumor tissues was significantly upregulated than in normal tissues. In HNSC, patients with high CCR5 expression levels had worse overall survival (OS, HR = 0.59, p = 0.00015) and worse recurrence-free survival (RFS, HR = 3.27, p = 0.00098). Upregulation of CCR5 expression is closely associated with immunomodulators, chemokines, and infiltrating levels of CD4+ T cells, neutrophils, macrophages, and myeloid dendritic cells. Furthermore, upregulated CCR5 was significantly associated with different immune markers in the immune cell subsets of HNSC. CONCLUSIONS: High expression of CCR5 plays an important prognostic role in HNSC patients and may serve as a prognostic biomarker correlated with immune infiltration, and further studies are still needed to investigate therapeutic targeting HNSC patients in the future.

Clinical and Epidemiological Features of Scaphoid Fracture Nonunion: A Hospital-Based Study in Beijing, China.

OBJECTIVE: Studies exploring the epidemiological characteristics of scaphoid fracture nonunion are important to understand the causes and lead to effective prevention strategy. However, such knowledge is limited especially in China. This study aims to reveal the clinical and epidemiological features of scaphoid fracture nonunion in Chinese patients. METHODS: This was a retrospective study, which was based on patients with scaphoid fracture nonunion treated in a Chinese national orthopedic referral center from 1 August 2009 to 1 August 2020. The basic demographic and clinical characteristics, including gender, age at diagnosis of scaphoid fracture nonunion, dominant hand, the location of fracture, the side, the causes of the injury, age of the injury, age of the treatment for scaphoid fracture nonunion, and the delay period, were retrieved from the medical records. The patients were divided into a non-delay group and a delay group based on whether they had visited the doctor within 1 month after the injury. Scaphoid fracture was classified into the proximal, waist, and distal fractures according to the location. The t-test or Mann-Whitney U test was used to compare the difference between groups when the dependent variable is continuous, while a chi-square test was used when the dependent variable is categorical. RESULTS: A total of 363 patients were included in this study. The mean age at the diagnosis of scaphoid fracture nonunion was 32 (ranging from 14 to 78). Waist fracture nonunion (76.5%) was most common. Among the 169 patients who sought medical care within 1 month after the injury (non-delay group), more than half (90 cases) were misdiagnosed. 23 cases could not recall the injury, so the time of delay could not be determined. Among the 171 patients who did not seek medical care for acute injury (delay group), the average time was 52 months between the initial injury and the treatment. The proportion of waist nonunions was higher among patients in the delay group than that in the non-delay group. CONCLUSIONS: Nonunion of scaphoid fracture is caused mainly by delayed treatment and misdiagnosis in China, suggesting that timely treatment and improved diagnosis could lower the prevalence. The fracture location may be a factor contributing to the delaying of seeking medical care.

Frameshift Mutation in a Chinese Patient with Brachydactyly Type C Involving the Third Metacarpal: A Case Report.

Brachydactyly is a common feature of congenital hand anomalies characterized by shortening of the phalanges and/or metacarpals. Mutation of growth differentiation factor-5 (GDF5) may result in loss of appearance and function in brachydactyly type C (BDC). Herein, we describe an 11 year-old Chinese BDC patient with significant shortening of the 1st, 2nd, 3rd, and 5th digits. Notably, according to the analysis of metacarpophalangeal pattern profiles, we do not think the 4th digit appears unaffected as usual. In this patient a novel heterozygous frameshift mutation was identified (c.349delG) causing termination of translation after translating six amino acids from codon 117 (p.A117fs*6). This mutation is located in the propeptide region of GDF5, causing GDF5 haploinsufficiency in BDC. Considering our results expanding the genetic spectrum of BDC-causing mutations, further molecular analysis to diagnose and reclassify isolated brachydactyly on the basis of genotype rather than phenotype is warranted.

Treatment of Congenital Radioulnar Synostosis Using a Free Vascularized Fascia Lata Graft.

OBJECTIVE: To describe the modified mobilization surgery technique that uses a free vascularized fascia lata graft as the interposition graft, and to evaluate the outcome of this procedure in treating congenital radioulnar synostosis (CRUS). METHODS: Eleven patients (eight boys and three girls with an average age of 6.0 years) were treated using this procedure between 2012 and 2017 in our institution. Five bilateral cases (four left forearms and one right forearm were treated), and six unilateral cases (three left forearms and three right forearms) were included. All 11 cases were treated with mobilization procedure with free vascularized fascia lata as the interposition graft, and were followed-up for an average of 2.2 years (range, 2-4 years). The parental satisfaction, postoperative ankylosis at proximal radioulnar joint, and active range of forearm rotation motion (measured by physical examination) were evaluated at the last follow-up. RESULTS: The average preoperative fixed pronation angle was 67.3° (range, 20°-90°). Ipsilateral thumb hypoplasia was noted in one case, and cleft palate and bilateral thumb hypoplasia were noted in one case; none of the patients had a family history of congenital radioulnar synostosis. Pronation and supination splints were used 3 days after the operation and were worn every night for 4-6 months postoperatively. Active and passive rehabilitation for elbow flexion and forearm rotation was initiated 4 weeks postoperatively. All patients were followed up for at least 2 years (average, 26 months; range, 24-48 months). The average forearm pronation range was 39° (range, 20°-60°), and the average forearm supination range was 33.2° (range, 10°-60°) at the latest follow-up. Re-ankylosis occurred in one case. An osseous bridge developed between the radius and ulna at the osteotomy site in one case. Radial nerve paralysis developed in two cases and spontaneously resolved 2 months later. Plate breakage was noted in one case 9 weeks postoperatively; however, union was achieved 7 months later. CONCLUSION: Mobilization of proximal radioulnar synostosis using a free vascularized fascia lata graft as the interposition graft may prevent re-ankylosis and restore the forearm rotation function, making it a good option for the surgical treatment of CRUS.

Clinical features and ultrasound findings of a rare musculoskeletal system disease-neuromuscular choristoma.

BACKGROUND: Neuromuscular choristomas (NMCs), are extremely rare developmental lesions that, have been previously established associated with recurrent fibromatosis after surgery, leading to several operations or even amputation. However, reports on the ultrasound imaging features and clinical conditions of NMCs are rare. The purpose of this study is to describe the ultrasound features and clinical analysis of NMCs to provide suggestions to identify the optimal management strategy. METHODS: From September 2020 to September 2021, 7 patients with a confirmed diagnosis of NMC who underwent ultrasound examination in our department were enrolled in our study. Physical examinations were performed to detect motor deficits, sensory deficits, neuropathic pain, limb undergrowth, muscular atrophy, cavus foot and bone dysplasia. Ultrasound imaging was performed and investigated both in affected nerves and neuromuscular choristomas associated desmoid-type fibromatosis (NMC-DTF). All patients had a definite history and regular follow-up. The clinical course, physical examinations, ultrasound features and pathologic results of NMC patients were analyzed. RESULTS: Seven patients with an average age of 7.0 ± 7.2 years (range: 2-22 years) were enrolled in our study. The affected nerves included the sciatic nerve (6 cases) and the brachial plexus (1 case). Six patients (85.7%) presented with limb undergrowth, 6 (85.7%) with muscular atrophy, and 5 (71.4%) with cavus foot deformity. Based on ultrasound findings, all the visibly affected nerve segments presented with hypoechoic and fusiform enlargement with intraneural skeletal muscle elements. Five patients (71.4%) had NMC-DTFs at the site of the affected nerve. All NMC-DTFs were shown as hypoechoic solid lesions adjacent to the nerve and were well circumscribed. In the subset of the surgery group, all 5 patients presented with progression to NMC-DTFs at the site of the NMCs. No fibromatosis was detected in the other two nonsurgical patients. CONCLUSIONS: Understanding the typical ultrasound features and clinically associated conditions would support the early diagnosis of this rare disease. When a potential diagnosis is determined, an invasive procedure such as biopsy or resection might not be a good choice given the frequent occurrence of complications such as aggressive recurrence.

The Influence of Personality and Demographic Characteristics on Aggressive Driving Behaviors in Eastern Chinese Drivers.

PURPOSE: Road safety research is important due to the large number of road traffic fatalities globally. This study investigated the influences of age, driving experience and other covariates on aggressive driving behavior. METHODS: A cross-sectional survey was conducted in Yixing City, Wuxi City, Jiangsu Province, China. Regression analysis was applied to explore the influences of age and driving experience and their interactions with other covariates on aggressive driving behavior. Two analyses methodologies were used to assess the simple effect of the interactions. Firstly, the Jamovi automatic analysis classification program was used to calculate the simple slope test. Second, the SPSS macro program was also used to calculate the simple slope test also. RESULTS: A total of 570 drivers (247 males, 282 females) participated in the survey. A negative correlation was found between age and aggressive driving behaviors, and a positive correlation was found between neuroticism and aggressive driving behaviors in the multiple regression analysis. Significant associations were also found between age, driving experience, and depression, as well as age, driving experience, and neuroticism. Simple slope tests showed that depressive symptoms could increase aggressive behaviors in the elderly and experienced drivers. When experiencing neuroticism, individuals with higher driving experience were more aggressive in driving than shorter experienced drivers. CONCLUSION: Age and neuroticism influenced aggressive driving behaviors. Veteran drivers could be aggressive drivers when experiencing depressive symptoms or neuroticism. Mobile intervention could be sent to the potentially risky drivers, which would be safe and broadly feasible to prevent aggressive driving behavior in the background of COVID-19.

MECOM-related disorder: Radioulnar synostosis without hematological aberration due to unique variants.

PURPOSE: The etiology for a considerable proportion of patients with congenital radioulnar synostosis (RUS) remains unclear. This study aimed to investigate the genetic cause of RUS without a known cause. METHODS: Patients with RUS were investigated. Exome sequencing and/or Sanger sequencing was performed. Bioinformatics analysis was also performed. Pathogenicity was evaluated for variants of interest. RESULTS: We identified unique missense variants in MECOM (encodes EVI1) associated with RUS in 8 families. Of them, 6 families had variants in residue R781, including 3 families with R781C (c.2341C>T), 2 families with R781H (c.2342G>A), and 1 family with R781L (c.2342G>T). Another 2 variants included I783T (c.2348T>C) in 1 family and Q777E (c.2329C>G) in 1 family. All these variants were clustered within the ninth zinc finger motif of EVI1. Phenotype evaluation identified that most of these patients with RUS harboring mutant MECOM had finger malformations, but none of them had identifiable hematological abnormalities. Functional experiments showed that MECOM R781C led to alterations in TGF-ß-mediated transcriptional responses. CONCLUSION: This study examined MECOM variants by focusing on RUS instead of hematological abnormalities. The R781 residue in EVI1 is a hotspot for human RUS variants. Mutant MECOM is the second most common cause for familial RUS.

A genotype and phenotype analysis of SMAD6 mutant patients with radioulnar synostosis.

BACKGROUND: SMAD6 variants have been reported in patients with radioulnar synostosis (RUS). This study aimed to investigate the genotypes and phenotypes for a large cohort of patients with RUS having mutant SMAD6. METHODS: Genomic DNA samples were isolated from 251 RUS sporadic patients (with their parents) and 27 RUS pedigrees. Sanger sequencing was performed for the SMAD6 coding regions. For positive probands, co-segregation and parental-origin analysis of SMAD6 variants and phenotypic re-evaluation were performed for their family members. RESULTS: We identified 50 RUS probands with SMAD6 variants (13 co-segregated with RUS in pedigrees and 37 in RUS-sporadic patients). Based on the new and previous data, we identified SMAD6 mutated in 16/38 RUS pedigrees and 61/393 RUS sporadic patients, respectively. Overall, 93 SMAD6 mutant patients with RUS were identified, among which 29 patients had unilateral RUS, where the left side was more involved than the right side (left:right = 20:9). Female protective effects and non-full penetrance were observed, in which only 6.90% mothers (vs. ~50% fathers) of SMAD6 mutant RUS probands had RUS. Pleiotropy was observed as a re-evaluation of SMAD6 mutant families identified: (a) three families had axial skeletal malformations; (b) two families had polydactyly; and (c) eight families had other known malformations. CONCLUSION: SMAD6 was mutated in 42.11% RUS pedigrees and 15.52% RUS sporadic patients. The RUS patients with SMAD6 variants exhibit both non-full-penetrance, variable expressivity, pleiotropy, female protective effects, and the left side is more susceptible than the right side.

Safety and efficacy of a nerve matrix membrane as a collagen nerve wrapping: a randomized, single-blind, multicenter clinical trial.

A new nerve matrix membrane derived from decellularized porcine nerves has been shown to retain the major extracellular matrix components, and to be effective in preventing adhesion between the nerve anastomosis sites and the surrounding tissues in a rat sciatic nerve transection model, thereby enhancing regeneration of the nerve. The effectiveness of the membrane may be attributed to its various bioactive components. In this prospective, randomized, single-blind, parallel-controlled multicenter clinical trial, we compared the safety and efficacy of the new nerve matrix membrane with a previously approved bovine tendon-derived type I collagen nerve wrapping. A total of 120 patients with peripheral nerve injury were recruited from Beijing Jishuitan Hospital, The First Bethune Hospital of Jilin University, and Yantai Yuhuangding Hospital, China. The patients were randomly assigned to undergo end-to-end and tension-free neurorrhaphy with nerve matrix membrane (n = 60, 52 male, 8 female, mean age 41.34 years, experimental group) or tendon-derived collagen nerve wrapping (n = 60, 42 male, 18 female, mean age 40.17 years, control group). Patients were followed-up at 14 ± 5, 30 ± 7, 90 ± 10 and 180 ± 20 days after the operation. Safety evaluation included analyses of local and systemic reactions, related laboratory tests, and adverse reactions. Efficacy evaluation included a static 2-point discrimination test, a moving 2-point discrimination test, and a Semmes-Weinstein monofilament examination. Sensory nerve function was evaluated with the British Medical Research Council Scale and Semmes-Weinstein monofilament examination. The ratio (percentage) of patients with excellent to good results in sensory nerve recovery 180 ± 20 days after the treatment was used as the primary effectiveness index. The percentages of patients with excellent to good results in the experimental and control groups were 98.00% and 94.44%, respectively, with no significant difference between the two groups. There were no significant differences in the results of routine blood tests, liver and renal function tests, coagulation function tests, or immunoglobulin tests at 14 and 180 days postoperatively between the two groups. These findings suggest that the novel nerve matrix membrane is similar in efficacy to the commercially-available bovine-derived collagen membrane in the repair of peripheral nerve injury, and it may therefore serve as an alternative in the clinical setting. The clinical trial was approved by the Institutional Ethics Committee of Beijing Jishuitan Hospital, China (approval No. 20160902) on October 8, 2016, the Institutional Ethics Committee of the First Bethune Hospital of Jilin University, China (approval No. 160518-088) on December 14, 2016, and the Institutional Ethics Committee of Yantai Yuhuangding Hospital, China (approval No. 2016-10-01) on December 9, 2016. The clinical trial was registered with the Chinese Clinical Trial Registry (registration number: ChiCTR2000033324) on May 28, 2020.

Accuracy of fluoroscopic examination in the treatment of Bennett's fracture.

BACKGROUND: Restoration of joint congruity is an important factor for the prevention of subsequent arthritis in patients with Bennett's fracture. Surgical treatment of Bennett's fracture is thus generally recommended for displaced intra-articular fractures to the proximal aspect of the thumb metacarpal. Fluoroscopic examination is used to evaluate the adequacy of closed reduction after pinning of Bennett's fracture. The purpose of this study was to determine the accuracy of fluoroscopy to determine the reduction of Bennett's fractures. METHODS: A model was created, to mimic a Bennett's fracture utilizing ten fresh-frozen cadaveric hands. An oblique cut was made in the proximal aspect of the thumb metacarpal using an oscillating saw. The small oblique fragment involved 1/4-1/3 of the joint surface was then shifted in position creating a step-off or gap at the fracture site. An anatomical reduction model, gap models (1 mm, 2 mm, 3 mm), and step-off models (1 mm, 2 mm, 3 mm) were created using percutaneous fixation with two 1.0 mm Kirschner wires for each cadaveric hand. Fluoroscopic assessment then took place and was reviewed by 2 attending hand surgeons blinded to the actual position. Their estimated fluoroscopic position was then compared to the actual displacement. RESULTS: The step-off and gap on fluoroscopic examination showed a significant difference compared to the step-off and gap from direct visualization. The frequency of underestimation for the 3 mm displacement models from the fluoroscopic examination was 60%. The frequency for overestimated was 9% for the models in which displacement was within 2 mm (0, 1, 2 mm). CONCLUSIONS: The assessment of articular gap and step-off using PA (postero-anterior), AP (antero-posterior), and lateral view of fluoroscopic examination is not accurate as compared to the examination by direct visualization. Surgeons need to be aware that PA, AP and lateral view of fluoroscopic examination alone may not be sufficient to judge the final position of a reduced Bennett's fracture. Other methods such as live fluoroscopy in multiple different planes, 3-dimensional fluoroscopy or arthroscopic examination should be considered.