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In the chemical-mechanical polishing (CMP) process, the abrasive particles in the polishing slurry tend to agglomerate easily and crystallize on the equipment surfaces during recycling, which can lead to poor wafer processing quality and additional tedious cleaning work. To overcome this issue, a simple and cost-effective self-cleaning surface preparation method has been developed. In this study, elastic and stretchable hydroxyl polydimethylsiloxane (PDMS-OH) was selected as the functional material, it was chelated with pentaerythritol tetra(3-mercapto propionate), and then 2-(perfluorooctyl)ethyl methacrylate was further grafted in situ to the polymer chains via a photoinduced thiol-ene click reaction. Hydrophobically modified micronanoscale silica particles were used to construct robust hierarchical micronanostructures while imparting stable mechanical wear resistance to the coating. The resulting superamphiphobic film exhibits the "lotus effect" and exceptional self-cleaning ability, repelling liquids such as water, hexadecane, and polishing slurry. Furthermore, the coating demonstrated outstanding chemical resistance and antifouling ability. Thus, it provides a feasible solution for preventing abrasive crystallization at critical locations where the polishing slurry flows in the CMP equipment. This work contributes to the enhanced application of superrepellent coatings in the CMP stage of semiconductor material processing.
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OBJECTIVE: To evaluate the efficacy of total elbow arthroplasty in treatment of distal humeral fracture in the elderly. METHODS: A total of 24 elderly patients who were diagnosed of distal humeral fracture and received Coorad-Morry prosthesis arthroplasty were retrospectively selected and analyzed from Beijing Jishuitan Hospital from 2003 to 2009. X ray examination of elbow joint and clinical evaluation were conducted in the follow-up; Mayo Elbow Performance Score (MEPS) was used in the last follow-up to evaluate patients' elbow function. RESULTS: A total of 20 patients with intact follow-up information were included in the final analysis, with mean follow-up length 92 months (65 - 136), mean VAS score 0.8 (0 - 2), extension degree of elbow 25 (0 - 60)degrees, flexion degree 112 (80 - 135)degrees; Mean MEPS was 88.5, with 7 excellent, 8 good, and 1 fair. Two patients had severe heterotopic ossification, 3 patients had ulnar neuropathy, 2 of which were temporary. One patient had superficial infection, and 1 had aseptic loosening in the humeral part, but did not receive revision surgery. CONCLUSION: Total elbow arthroplasty can successfully treat distal humeral fracture in the elderly and achieve satisfactory result which can last for a long time.
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Artroplastia de Substituição do Cotovelo , Fraturas do Úmero/cirurgia , Idoso , Cotovelo/cirurgia , Articulação do Cotovelo/cirurgia , Humanos , Prótese Articular , Amplitude de Movimento Articular , Reoperação , Estudos Retrospectivos , Resultado do TratamentoRESUMO
STUDY DESIGN: A retrospective study. OBJECTIVE: To investigate whether the preoperative classification and changes in the intramedullary increased signal intensity (ISI) on axial T2-weighted magnetic resonance imaging (MRI) reflect the postoperative functional outcome in patients after laminoplasty for cervical spondylotic myelopathy (CSM). SUMMARY OF BACKGROUND DATA: Although patients with CSM exhibit ISI on axial MRI, the association between ISI (preoperative classification and changes) and surgical outcomes has not been investigated. PATIENTS AND METHODS: We retrospectively included patients with CSM who underwent MRI preoperatively and at least 10 years postoperatively after laminoplasty between January 2009 and December 2010. According to axial images for the cervical compressive myelopathy (Ax-CCM) system, the ISI on axial images was classified as follows: type 0, normal; type 1, diffuse; type 2, fuzzy focal; and type 3, discrete focal. Functional outcomes, as measured by the Japanese Orthopaedic Association (JOA) score and JOA recovery rate, were evaluated based on the Ax-CCM classification. RESULTS: Forty-three patients were enrolled. The mean follow-up time was 11.0±1.0 years. At the final follow-up, postoperative changes in the type of ISI were observed in 62.8% of patients. The type of ISI improved in 5 patients (11.6%), remained unchanged in 16 patients (37.2%), and worsened in 22 patients (51.2%). Patients with preoperative type 2 ISI had worse postoperative JOA scores and JOA recovery rates than those with other types. A worse ISI type was related to a lower postoperative JOA score and a lower recovery rate at the final follow-up. CONCLUSIONS: Type 2 ISI was associated with poor postoperative symptoms and low postoperative function improvement. ISI changed after laminoplasty in 27 patients (62.8%), and worsened ISI was related to poor surgical outcomes.
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BACKGROUND: Thoracolumbar burst fractures are a common traumatic vertebral fracture in the spine, and pedicle screw fixation has been widely performed as a safe and effective procedure. However, after the stabilization of the thoracolumbar burst fractures, whether or not to remove the pedicle screw implant remains controversial. This review aimed to assess the benefits and risks of pedicle screw instrument removal after fixation of thoracolumbar burst fractures. METHODS: Data sources, including PubMed, EMBASE, Cochrane Library, Web of Science, Google Scholar, and Clinical trials.gov, were comprehensively searched. All types of human studies that reported the benefits and risks of implant removal after thoracolumbar burst fractures, were selected for inclusion. Clinical outcomes after implant removal were collected for further evaluation. RESULTS: A total of 4051 papers were retrieved, of which 35 studies were eligible for inclusion in the review, including four case reports, four case series, and 27 observational studies. The possible risks of pedicle screw removal after fixation of thoracolumbar burst fractures include the progression of the kyphotic deformity and surgical complications (e.g., surgical site infection, neurovascular injury, worsening pain, revision surgery), while the potential benefits of pedicle screw removal mainly include improved segmental range of motion and alleviated pain and disability. Therefore, the potential benefits and possible risks should be weighed to support patient-specific clinical decision-making about the removal of pedicle screws after the successful fusion of thoracolumbar burst fractures. CONCLUSIONS: There was conflicting evidence regarding the benefits and harms of implant removal after successful fixation of thoracolumbar burst fractures, and the current literature does not support the general recommendation for removal of the pedicle screw instruments, which may expose the patients to unnecessary complications and costs. Both surgeons and patients should be aware of the indications and have appropriate expectations of the benefits and risks of implant removal. The decision to remove the implant or not should be made individually and cautiously by the surgeon in consultation with the patient. Further studies are warranted to clarify this issue. LEVEL OF EVIDENCE: level 1.
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INTRODUCTION: The application of robotic navigation during spine surgery has advanced rapidly over the past two decades, especially in the last 5 years. Robotic systems in spine surgery may offer potential advantages for both patients and surgeons. This article serves as an update to our previous review and explores the current status of spine surgery robots in clinical settings. AREAS COVERED: We evaluated the literature published from 2020 to 2022 on the outcomes of robotics-assisted spine surgery, including accuracy and its influencing factors, radiation exposure, and follow-up results. EXPERT OPINION: The application of robotics in spine surgery has driven spine surgery into a new era of precision treatment through a form of artificial intelligence assistance that compensates for the limitations of human abilities. Modularized robot configurations, intelligent alignment and planning incorporating multimodal images, efficient and simple human - machine interaction, accurate surgical status monitoring, and safe control strategies are the main technical features for the development of orthopedic surgical robots. The use of robotics-assisted decompression, osteotomies, and decision-making warrants further study. Future investigations should focus on patients' needs while continuing to explore in-depth medical - industrial collaborative development innovations that improve the overall utilization of artificial intelligence and sophistication in disease treatment.
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Procedimentos Cirúrgicos Robóticos , Robótica , Cirurgia Assistida por Computador , Humanos , Inteligência Artificial , Procedimentos Cirúrgicos Robóticos/métodos , Coluna Vertebral/cirurgia , Cirurgia Assistida por Computador/métodosRESUMO
OBJECTIVE: To investigate nano-hydroxyapatite (nHA) pellets as carriers for vancomycin in the treatment of chronic osteomyelitis and bone defects due to methicillin-resistant Staphylococcus aureus (MRSA) strains. METHODS: Chronic osteomyelitis was induced in 45 New Zealand white rabbits. After 3 weeks (chronic infection), all animals were treated with debridement. The rabbits were divided into an experimental group (the bone was filled with vancomycin-loaded nHA pellets), a control group (the bone was filled with nHA pellets alone), and a blank group. The drug release profiles were determined in vitro and in vivo. X-rays, bone specimens, and microorganism cultures were used to evaluate the efficacy of the treatments. RESULTS: Following a rapid initial release into the circulation, the drug concentration remained effective in the osseous and soft tissues for 12 weeks after debridement. Within 3 months, all rabbits in the experimental group recovered from osteomyelitis without a recurrence of the infection and the bone defects were partially repaired, whereas the infection and bone defects persisted in the control and blank groups. CONCLUSIONS: The results demonstrate that vancomycin-loaded nHA pellets successfully repair bone defects and control infection in MRSA-induced chronic osteomyelitis. In addition, nHA is an effective and safe controlled-release vancomycin carrier for chronic osteomyelitis with bone defects that is induced by MRSA.
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Antibacterianos/uso terapêutico , Portadores de Fármacos/uso terapêutico , Staphylococcus aureus Resistente à Meticilina , Osteomielite/tratamento farmacológico , Infecções Estafilocócicas/tratamento farmacológico , Vancomicina/uso terapêutico , Animais , Antibacterianos/sangue , Antibacterianos/farmacocinética , Carga Bacteriana , Modelos Animais de Doenças , Implantes de Medicamento/uso terapêutico , Durapatita/uso terapêutico , Nanoestruturas/uso terapêutico , Osteomielite/diagnóstico por imagem , Osteomielite/microbiologia , Osteomielite/patologia , Coelhos , Radiografia , Infecções Estafilocócicas/diagnóstico por imagem , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/patologia , Tíbia/metabolismo , Vancomicina/sangue , Vancomicina/farmacocinéticaRESUMO
STUDY DESIGN: Retrospective study. OBJECTIVE: Our purpose was to evaluate spinal rotation measurement by scoliometer or EOS Imagings with reference to that by CT images, and to clarify their applicability in clinical practice. METHODS: Patients with adolescent idiopathic scoliosis (AIS) who were indicated for surgery were enrolled and the informed consents were obtained. The angle of trunk rotation (ATR) was measured by the scoliometer. Apical vertebral rotation (AVR) was measured with EOS Imaging and CT images. Paired T tests were used to compare the measurements between ATR or AVR-EOS and AVR-CT. Pearson correlation analysis was performed to explore the relationship between ATR or AVR-EOS and AVR-CT. Then subgroup analysis was performed. RESULTS: Forty-seven consecutive AIS patients with 62 curves were identified. In the whole group, the ATR, as well as AVR-EOS, was significantly smaller than the AVR-CT. Both ATR and AVR-EOS correlated with AVR-CT, although AVR-EOS correlated better. In thoracic group, there was no significant difference between ATR and AVR-CT (P = .236). A significant correlation was found between ATR and AVR-CT(r = .574, P < .001). In TL/L group, no significant difference was noted between AVR-EOS and AVR-CT (P = .414), and a significant correlation was found between AVR-EOS and AVR-CT(r = .824, P < .001). CONCLUSION: ATR by scoliometer is numerically similar to AVR by CT and may evaluate the spinal rotation more appropriately in thoracic spine. AVR by EOS is numerically similar to AVR by CT and may be more applicable in TL/L spine. Appropriate methods could be selected according to the location of the curve.
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A structure parameter, Sn = η(c)γ/τ(E), is proposed to represent the increase of effective viscosity due to the introduction of particles into a viscous liquid and to analyze the shear behavior of electrorheological (ER) fluids. Sn can divide the shear curves of ER fluids, τ/E(2) versus Sn, into three regimes, with two critical values Sn(c) of about 10(-4) and 10(-2), respectively. The two critical Sn(c) are applicable to ER fluids with different particle volume fractions φ in a wide range of shear rate γ and electric field E. When Sn < 10(-4), the shear behavior of ER fluids is mainly dominated by E and by shear rate when Sn > 10(-2). The electric current of ER fluids under E varied with shear stress in the same or the opposite trend in different shear rate ranges. Sn(c) also separates the conductivity variation of ER fluids into three regimes, corresponding to different structure evolutions. The change of Sn with particle volume fraction and E has also been discussed. The shear thickening in ER fluids can be characterized by Sn(c)(L) and Sn(c)(H) with a critical value about 10(-6). As an analogy to friction, the correspondence between τ/E(2) and friction coefficient, Sn and bearing numbers, as well as the similarity between the shear curve of ER fluids and the Stribeck curve of friction, indicate a possible friction origin in ER effect.
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BACKGROUND: A uperior adjacent vertebral fracture (SAVF) is a common complication after kyphoplasty. Intra-disc leakage is a significant risk factor of SAVF. However, to date, no studies on the prevention of SAVF after intra-disc leakage have been conducted. This study sought to evaluate the clinical outcome of prophylactic vertebral augmentation in high-risk patients, and explore the other risk factors of SAVF. METHODS: Of 2,571 patients who received kyphoplasty, 82 with intra-disc leakage were retrospectively enrolled in the study, and divided into 2 groups based on whether they had a superior level of prophylactic vertebral augmentation. To ensure that any possible early complications were examined, there was a minimum follow-up period of 12 months. RESULTS: The pre-operation parameters were comparable between the 2 groups. In the non-prophylactic group, 9 of 59 (15.3%) patients had SAVF superior to the level of intra-disc leakage. Of these 9 SAVF cases, 8 fractures (88.9%) occurred within 6 months after surgery. Overall, 14 (23.7%) patients developed a new fracture. In the prophylactic group, no patients had a SAVF (0.0%), but 3 (13.0%) had remote fractures (P=0.047 and 0.284). No complications were associated with vertebral augmentation. Further, the risk factor analysis showed that patients with comorbidities and a history of corticoid use had a higher risk of fracture compared with patients with none of these risk factor [odds ratios: 12.0, 95% confidence interval (CI): 1.0-143, and 34.3, 95% CI: 3.2-364.5, respectively]. CONCLUSIONS: Prophylactic vertebral augmentation can prevent SAVF without complications. Patients with comorbidities and a history of corticoid use had a higher risk of SAVF compared with patients without corticoid use. Thus, we recommend prophylactic vertebral augmentation in the selected high-risk patients.
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Fraturas por Compressão , Cifoplastia , Fraturas da Coluna Vertebral , Cimentos Ósseos , Fraturas por Compressão/cirurgia , Humanos , Cifoplastia/efeitos adversos , Estudos Retrospectivos , Fraturas da Coluna Vertebral/cirurgia , Resultado do TratamentoRESUMO
BACKGROUND: Infection and aseptic loosening are common complications of total elbow arthroplasty (TEA) and often require revision surgery. However, bone defects, along with other complications, bring an extra difficulty to the second surgery, especially for patients with a massive bone defect in the proximal ulna. Several methods including allograft or autograft have been introduced into practice, but none sufficiently solves these problems. METHODS: We conducted a new surgical method for patients with a massive ulnar bone defect needing revision TEA. During revision arthroplasty, the ulnar prosthesis was inserted into the radius as a salvage procedure. Four consecutive patients received revision arthroplasty with this method between 2013 and 2016. Patients' data were collected to evaluate the clinical outcome. RESULTS: All patients had a Grade III ulnar bone defect. At the last follow-up session, all patients reported a painless, functional elbow joint. Three patients suffered from a periprosthetic infection that was completely cured using the two-stage method. No major complications, including infection, aseptic loosening, or wound problems were found. One patient had a transient ulnar neuritis, and another had a transient radial neuritis. Both patients had full recovery at the last follow-up session. CONCLUSIONS: Inserting an ulnar prosthesis into the radius is a novel procedure for patients with a massive bone defect due to infection or aseptic loosening. It is a safe, quick, and effective treatment with a promising short-term outcome. This method should be provided as a salvage procedure for patients with a nonreconstructable ulnar bone defect.
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Próteses e Implantes , Rádio (Anatomia)/cirurgia , Reoperação/métodos , Ulna/cirurgia , Artroplastia de Substituição/métodos , Cotovelo/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Amplitude de Movimento Articular , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Adequate fixation of the opened laminar arch is the key indicator of a successful laminoplasty surgery; poor outcomes, including secondary narrowing of the spinal canal and a high risk of axial neck pain are possible when using a suturing method during conventional laminoplasty. Rigid fixation including spacers or bone struts yields satisfactory clinical outcomes. However, this approach is also associated with a longer surgical time and an increased risk of instrumentation dislodgement. Plate-only fixation with fusion was developed in our hospital to improve conventional laminoplasty; in addition, the supraspinous ligament is preserved in this procedure. We evaluated both the safety and efficacy of the procedure. Twenty-six patients with multilevel cervical degenerative disease were enrolled for selective open-door laminoplasty with miniplate fixation; autologous bone debris was placed on the hinge side to promote fusion, without bone struts on the open side. The Japanese Orthopedic Association (JOA) score, X-ray, three-dimensional CT scan and MRI were used for the pre- and postoperative evaluations. The mean follow-up period was 22 months (range=12-34 months), and all patients achieved osseous fusion within six months of the operation. Patients who underwent open-door laminoplasty showed an improvement in the JOA score of 60.7%; a 23.0% incidence of axial neck pain and a 3.2° loss of range of motion (ROM) were also observed. No instrumentation failure or clinical deterioration was observed in our study. Thus, open-door laminoplasty with miniplate fixation is a safe, simple surgery for multilevel cervical disease that has significant clinical efficacy. This approach can maintain the cervical ROM, reduce the incidence of postoperative axial neck pain, decrease surgical time and cost, and avoid complications related to fusion.
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Laminectomia/instrumentação , Laminectomia/métodos , Doenças Neurodegenerativas/cirurgia , Fusão Vertebral/métodos , Estenose Espinal/cirurgia , Absorciometria de Fóton , Análise de Variância , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia , Feminino , Humanos , Fixadores Internos , Masculino , Doenças Neurodegenerativas/complicações , Doenças Neurodegenerativas/diagnóstico por imagem , Estudos Retrospectivos , Estenose Espinal/complicações , Estenose Espinal/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Resultado do TratamentoRESUMO
By shearing electrorheological (ER) fluids between two concentric cylinders, we show a reversible shear thickening of ER fluids above a low critical shear rate (<1 s(-1)) and a high critical electric field strength (>100 V/mm), which can be characterized by a critical apparent viscosity. Shear thickening and electrostatic particle interaction-induced interparticle friction forces are considered to play an important role in the origin of lateral shear resistance of ER fluids, while the applied electric field controls the extent of shear thickening. The electric-field-controlled reversible shear thickening has implications for high-performance electrorheological-magnetorheological fluid design, clutch fluids with high friction forces triggered by applying a local electric field, other field-responsive materials, and intelligent systems.