Comparison of Treatment Outcomes of Different Immobilized Finger Positions After Repair of Flexor Tendon Rupture in Zones I and II: A Nonrandomized Controlled Trial With Historical Control Group.

Introduction The position of finger immobilization after flexor tendon rupture repair is changed to the extended position to prevent flexion contracture of the interphalangeal (IP) joint. However, in Strickland's assessment, We believe that a reduction in TAF (total active flexion) affects the outcome and that extension fixation is not necessarily the primary focus. For example, there are management methods that swap the fixed position between day and night. It is assumed that some effect is sought by placing the fingers in the flexed position. That is, the method of fixation is currently selected at individual facilities through twists and turns; however, the indications and criteria for selecting finger fixation positions are ambiguous, and they are apparently subject to the experience of therapists. This study aimed to characterize follow-up outcomes of flexion and extension fixation after zones I and II flexor tendon rupture repair. Methods This nonrandomized controlled trial with historical controls included 25 patients with flexor tendon ruptures of 30 fingers. The flexion fixation group consisted of 12 patients (n=16 fingers) and the extension fixation group consisted of 13 patients (n=14 fingers). The group with flexion fixation comprised patients who slept with their injured fingers in the flexed position (intervention group). The group with extension was retrospectively selected between April 2017 and March 2019, who slept with their injured finger in the extended position (historical control group). Strickland assessments of the range of motion (ROM) of each joint at the conclusion of hand therapy, the ratio of total active motion of the repaired, to the healthy finger (%TAF), and IP joint extension limitation angles were compared using Mann-Whitney U tests. Ratios of excellent and good ratings based on the Strickland assessment were compared using Fisher exact tests. Result The results of the Strickland assessment showed excellent or good outcomes for 22 (73%) of 30 fingers, which was in line with our previous findings. Strickland ratings of excellent were achieved in seven (44%) of 16 fingers and four (28%) of 14 fingers in the groups with flexion and extension fixation, respectively. The outcomes for two (22%) of 16 fingers and seven (78%) of 14 fingers in the groups with flexion and extension fixation were, respectively, rated as good. The proportion of patients rated as excellent was significantly higher in the group with flexion than extension fixation (p=0.040). The %TAF and the active flexion angle of the distal interphalangeal (DIP) joint were higher in the group with flexion than extension fixation (p=0008 and p=0.025, respectively). Furthermore, the total angle of the IP joint limit of extension did not significantly differ between the groups. Conclusion Flexion fixation after flexor tendon rupture achieved an excellent Strickland rating and was more effective than extension fixation, especially in terms of the active flexion ROM of the DIP joint. Flexion fixation might be an alternative to extension fixation because the range of flexion should be greater and might provide a range of finger extension motion equivalent to that of extension fixation.

Comperative evaluation of the current and new design miniplate fixation techniques of the advanced sagittal split ramus osteotomy using three-dimensional finite element analysis

Background: The aim of this study was to evaluate the stress occurring in the fixation systems both developed in various geometric designs for this study and currently used in sagittal split ramus advancement osteotomy using finite element analysis. Material and Methods: The finite element model that imitates three-dimensional sagittal split advancement osteotomy was fixed in 10 different miniplate fixation methods: one miniplate fixed with four monocortical screws in a horizontal and oblique pattern; four-hole two miniplates with eight monocortical screws; five-hole miniplate fixed with four monocortical and one bicortical screws; six-hole straight and curved miniplates fixed with six monocortical screws in different geometric designs. Unilateral masticatory muscle loads that have previously determined in the literature were applied to the model at the anatomical muscle attachment regions and the data obtained from finite element analysis and static linear analysis methods were recorded as Von mises, maximum principle and minimum principle stress values. Results: It was observed from the results that maximum stress occurred in Group 1, which consisted of double backward T-shaped miniplate with 6-holes and, minimum stress occured in group 10, which mimiced hybrid system with one miniplate and four monocortical and one bicortical screws. Conclusions: Based on our results, the stress on the miniplates changes according to the geometric designs and the stress on the miniplate decreases as the numbers of miniplates and bars increase. The hybrid miniplate may be preferred by the surgeon as it will be exposed to less stress in excessive mandibular advancements by using the advantages of both the miniplate and the bicortical screw. (AU)

A practical approach to the sampling, fixation, softening, and sectioning of whole honey bees for histologic evaluation.

The Western honey bee (Apis mellifera) is economically important as the primary managed pollinator of many agricultural crops and for the production of various hive-related commodities. Honey bees are not classically or thoroughly covered in veterinary pathology training programs. Given their unique anatomic and biological differences from the other species more traditionally evaluated by veterinary pathologists, establishing routine and consistent methods for processing samples for histology ensures accurate diagnostic and research conclusions. We developed and tested several field protocols for the sampling of honey bees. We compared the tissue-quality outcomes for worker bees fixed, collected, and/or softened under the following protocols: 1) routine formalin fixation; 2) softening chitin via exposure to Nair for 2 d or 3) 5 d; 4) shortened times between formalin submersion and trimming of body segments to enhance penetration of formalin into internal tissues; 5) ethanol submersion of specimen prior to formalin fixation; 6) indirect dry ice exposure; and 7) prolonged -80°C storage. Routine formalin fixation, exposure to Nair for 2 d, indirect dry ice exposure, and trimming body segments within 2 h of formalin submersion resulted in the highest quality histologic tissue sections. The poorest quality sections resulted from softening of chitin by exposure to Nair for 5 d, submersion in ethanol for 3 d before formalin fixation, and prolonged storage at -80°C. Our results indicate that routine formalin fixation is adequate, and that immobilizing bees with indirect dry ice exposure aids in sample collection without negatively impacting the quality of histologic sections.

Stability of different fixation methods after reduction malarplasty under average and maximum masticatory forces: a finite element analysis.

BACKGROUND: Although titanium plates/screws are effective fixation methods (FM) after L-shaped osteotomy reduction malarplasty (LORM), the ideal FM remains controversial. This first finite element analysis (FEA) aimed to study the effect of various zygomatic body/zygomatic arch FM combinations and their placement vectors on the zygoma complex stability after virtual LORM under the effect of both average (150 N/mm2) and maximum (750 N/mm2) forces and three-dimensional (3D) mapping of stress and strain parameters distribution over the zygomatic bone, fixation methods, and total model. RESULTS: The fixation methods about the short-arm of the L-shaped osteotomy showed lower stress, strain, and displacement values than those across the long-arm osteotomy site. Combined with any zygomatic arch fixation methods (ZAFm), the two bicortical screws group (2LS) on the zygomatic body osteotomy site resulted in smaller displacements and the lowest zygoma bone stress and displacement when combined with Mortice-Tenon structure (MT) as zygomatic arch fixation method. Applied forces caused statistically significant differences in zygomatic bone stress (P < 0.001 and P = 0.001) and displacement (P = 0.001 and P = 0.002). CONCLUSION: All FMs both on the zygomatic body and zygomatic arch provide adequate zygomatic complex stability after LORM. The 2LS group showed better resistance than rectangular plate (RP) and square plate (SP) with lower stress concentrations. The L-shaped plate with short-wing on the maxilla (LPwM) is more stable than having the short-wing on the zygoma bone (LPwZ). Future prospective clinical studies are required to validate the current findings.

Three-dimensional radiographic assessment of different fixation methods stability after l-shaped osteotomy reduction malarplasty: A comparative retrospective study.

BACKGROUND: Reduction malarplasty (RM) is a common facial contouring procedure among Orientals. Currently, fixation methods selection and placement vectors are controversial. Therefore, this study aimed to evaluate the effect of different zygomatic complex fixation methods on surgical outcomes stability after RM. MATERIALS AND METHODS: In this retrospective study, 60 consented patients (120 operated zygoma) who met inclusion criteria were included. ITK-SNAP and 3D Slicer software were used to measure the displacement of the zygomatic complex using postoperative CTs (T1: one week and T2: six months). The region of interest included zygomatic body fixation methods (ZBFm), namely: two bicortical screws (2LS); an l-shaped plate with one bicortical screw (LPLS); an l-shaped plate with short-wing on the zygoma (LPwZ) and on the maxilla (LPwM), combined with zygomatic arch fixation methods (ZAFm), including Mortice-Tenon (MT); 3-hole plate (3HP); and short screw (SS). ANOVA test was used to compare the displacement values among ZBFm/ZAFm combinations. RESULTS: The 2LS and LPLS groups showed lower displacement than the single l-shaped plate (P< 0.001, P = 0.001), which performed better when the short-wing was fixated on the maxilla (0.9 ± 0.4 mm and 1.2 ± 0.6 mm respectively). CONCLUSION: After RM, the two-bridge fixation methods (2LS and LPLS) provide better stability than the single l-shaped plate. All ZAF methods showed similar stability when combined with 2LS or LPLS as zygomatic body fixation methods.

Biomechanical analysis of different fixation methods for Rorabeck II supracondylar femoral fractures after total knee arthroplasty.

BACKGROUND: Locking plate (LP) and retrograde intramedullary nailing (RIMN) are widely used to fix Rorabeck II supracondylar femoral fractures after total knee arthroplasty (TKA). The biomechanical properties of the implant used for treatment influence its longevity. Therefore, we aimed to evaluate the biomechanical stability of different fixations using finite element analysis. METHODS: Seven finite element models (FEMs) were established, including LP groups (short LP, long LP, and double LP), RIMN groups (short RIMN and long RIMN), and mixed groups (long LP with short RIMN and long LP with long RIMN). The stress of the implants around the fracture area was calculated to evaluate the biomechanical stability under loads. RESULTS: Stress was mainly distributed around the fracture area in all models. The stress-shielding phenomenon was most evident in the short LP. The trend in maximum equivalent stress values of implants around the fracture area for the seven internal fixations was: short LP (324.63 MPa) > short RIMN (306.37 MPa) > long LP (275.06 MPa) > long RIMN (262.74 MPa) > double LP (203.19 MPa) > long LP with short RIMN (124.42 MPa) > long LP with long RIMN (112.41 MPa). We found that the double LP can better disperse the stress than a single LP, and a long LP with long RIMN can prevent stress concentration and make the stress distribution more uniform. CONCLUSION: From the perspective of biomechanics, long LP with long RIMN can stabilize fractures and avoid stress concentration in Rorabeck II supracondylar femoral fractures after TKA.

Impact of Sample Preparation Methods on Single-Cell X-ray Microscopy and Light Elemental Analysis Evaluated by Combined Low Energy X-ray Fluorescence, STXM and AFM.

BACKGROUND: Although X-ray fluorescence microscopy is becoming a widely used technique for single-cell analysis, sample preparation for this microscopy remains one of the main challenges in obtaining optimal conditions for the measurements in the X-ray regime. The information available to researchers on sample treatment is inadequate and unclear, sometimes leading to wasted time and jeopardizing the experiment's success. Many cell fixation methods have been described, but none of them have been systematically tested and declared the most suitable for synchrotron X-ray microscopy. METHODS: The HEC-1-A endometrial cells, human spermatozoa, and human embryonic kidney (HEK-293) cells were fixed with organic solvents and cross-linking methods: 70% ethanol, 3.7%, and 2% paraformaldehyde; in addition, HEK-293 cells were subjected to methanol/ C3H6O treatment and cryofixation. Fixation methods were compared by coupling low-energy X-ray fluorescence with scanning transmission X-ray microscopy and atomic force microscopy. RESULTS: Organic solvents lead to greater dehydration of cells, which has the most significant effect on the distribution and depletion of diffusion elements. Paraformaldehyde provides robust and reproducible data. Finally, the cryofixed cells provide the best morphology and element content results. CONCLUSION: Although cryofixation seems to be the most appropriate method as it allows for keeping cells closer to physiological conditions, it has some technical limitations. Paraformaldehyde, when used at the average concentration of 3.7%, is also an excellent alternative for X-ray microscopy.

Optimal mask fixation method for frameless radiosurgery with Leksell Gamma Knife IconTM.

The Leksell Gamma Knife (LGK) IconTM is used for mask-based and frame-based fixation. The mask fixation provides a noninvasive method. However, an optimal mask fixation method is yet to be established. We evaluated the characteristics of three mask fixation methods (Plain, Folded, and Wide) for the LGK IconTM . Force-sensitive resistor sensors were attached to the forehead, supraorbital, zygoma, mandible, and occipital bone of the phantom, and digital humidity and temperature sensors were attached to both temporal lobes. Cone-beam computed tomography (CBCT) and high-definition motion management (HDMM) for each mask fixation method were used to evaluate the phantom motion during the initial application. Subsequently, the mask was removed and reapplied on the second (1st reapplication) and third days (2nd reapplication). In the initial application, forces acting on most portions of the phantom were stabilized within 1.5 h. The largest force acted on the occipital bone for the Plain and Wide methods and on the mandible for the Folded method. The temperature rapidly approaches the initial temperature, whereas the humidity gradually approached the initial humidity in all fixation methods. The Folded method exhibited a significantly lower translation along the Y-axis of the Leksell coordinate system, and rotations along all axes were under 0.5°. The HDMM values remained at 0.1 mm for all fixation methods. In the reapplications, the force acting on the occipital bone was significantly greater than that during the initial application for all mask fixation methods; the temperature and humidity remained unchanged. All mask fixation methods in the 1st reapplication were not significantly different from those in the 2nd reapplication. The Folded method is recommended as an optimal mask fixation for patients who require tight fixation; the Wide method can be considered if patient comfort is a priority.

Sindesmosis tibioperonea: diagnóstico, métodos de fijación y artroscopia

Introducción: Las lesiones de la sindesmosis tibioperonea son frecuentes tanto de forma aislada o asociadas a fracturas del maléolo posterior. El diagnóstico clínico es corroborado mediante estudios imagenológicos. Los métodos de fijación pueden ser rígidos o dinámicos. Objetivo: Actualizar aspectos sobre las lesiones de la sindesmosis tibioperonea en cuanto al diagnóstico, métodos de fijación y el empleo de la vía artroscópica. Método: La búsqueda y análisis de la información se realizó en un periodo de 61 días (1 de octubre al 30 de noviembre de 2022) y se emplearon las siguientes palabras: syndesmosis injury, ankle syndesmosis instability, syndesmosis instability AND tight rope ankle instability, posterior maleolar fracture. A partir de la información obtenida se realizó una revisión bibliográfica de un total de 258 artículos publicados en las bases de datos PubMed, Hinari, SciELO y Medline mediante el gestor de búsqueda y administrador de referencias EndNote. Desarrollo: Se hizo referencia a las maniobras clínicas para el diagnóstico y las clasificaciones tomográficas en caso de fractura asociada del maléolo posterior. Se mencionaron los métodos de fijación rígidos y dinámicos, donde se describieron las características de cada uno basado en varios factores. Se expusieron las ventajas de la vía artroscópica tanto para el diagnóstico como para el tratamiento. Conclusiones: Las lesiones de la sindesmosis tibioperonea distal son frecuentes. Los estudios tomográficos ofrecen ventajas al determinar la extensión de la fractura del maléolo posterior. La vía artroscópica ofrece múltiples ventajas diagnósticas y terapéuticas.

Introduction: Tibioperoneal syndesmosis injuries are frequent both in isolation or associated with posterior malleolus fractures. Clinical diagnosis is confirmed on imaging studies. Fixation methods might be rigid or dynamic as well. Objective: Provide new aspects related to tibioperoneal syndesmosis injuries in terms of diagnosis, fixation methods and the use of arthroscopic procedure. Method: Search and analysis of information needed were carried out in a period of 61 days (from October 1 to November 30, 2022) and the following words were used: syndesmosis injury, ankle syndesmosis instability, syndesmosis instability AND tight rope ankle instability, posterior maleolar fracture. Based on the information obtained, a bibliographic review of the total of 258 articles published in the PubMed, Hinari, SciELO and Medline databases was carried out using the search engine and reference manager EndNote. Development: It was expressed in the study aspects related to clinical management used in diagnostic and classification on the types of CT scan for fracture associated with posterior malleolar fracture. The rigid and dynamic fixation methods and its characteristics were mentioned as well. The arthroscopic approaches and its advantages for both diagnosis and treatment were presented. Conclusions: Distal tibioperoneal syndesmosis injuries are frequent ankle injury. Tomographic studies offer some advantages for determining how large the posterior malleolus fracture is. The arthroscopic approach offers multiple diagnostic and therapeutic advantages too.

Introdução: As lesões da sindesmose tibiofibular são frequentes isoladamente ou associadas a fraturas do maléolo posterior. O diagnóstico clínico é confirmado por exames de imagem. Os métodos de fixação podem ser rígidos ou dinâmicos. Objetivo: Atualizar aspectos das lesões da sindesmose tibiofibular quanto ao diagnóstico, métodos de fixação e uso da abordagem artroscópica. Método: A busca e análise das informações foi realizada em um período de 61 dias (1º de outubro a 30 de novembro de 2022) e foram utilizadas as seguintes palavras: syndesmosis injury, ankle syndesmosis instability, syndesmosis instability AND tight rope ankle instability, posterior maleolar fracture. Com base nas informações obtidas, foi realizada uma revisão bibliográfica de um total de 258 artigos publicados nas bases de dados PubMed, Hinari, SciELO e Medline, utilizando o gerenciador de busca e Gerenciador de referências do EndNote. Desenvolvimento: Foi feita referência a manobras clínicas para diagnóstico e classificações tomográficas em caso de fractura associada do maléolo posterior. Foram citados métodos de fixação rígidos e dinâmicos, onde foram descritas as características de cada um com base em vários fatores. As vantagens da abordagem artroscópica tanto para o diagnóstico quanto para o tratamento foram discutidas. Conclusões: As lesões da sindesmose tibiofibular distal são frequentes. Os estudos tomográficos oferecem vantagens na determinação da extensão da fratura do maléolo posterior. A abordagem artroscópica oferece múltiplas vantagens diagnósticas e terapêuticas.

Comparison of Functional and Radiographic Outcomes Between Two Fixation Methods for Extended Trochanteric Osteotomy in Revision Total Hip Arthroplasty: A Retrospective Cohort Study.

BACKGROUND: To compare the functional and radiographic outcomes between two fixation methods for extended trochanteric osteotomy (ETO) in revision total hip arthroplasty (rTHA). METHODS: Included in this study were 64 patients who underwent ETO in rTHA using either claw-plate fixation (claw-plate group, n = 31) or cable-alone fixation (cable group, n = 33) in our hospital from 2008 to 2020. The functional and radiographic results and complications were compared between the groups during a mean follow-up period of 64 and 78 months. RESULTS: The Harris hip score and visual analogue scale at the last follow-up improved significantly in both groups, showing no significant statistical difference between the two fixation methods. In the cable group, the mean abductor lever arm, the proximal migration, and medial migration in the affected hip were significantly decreased compared to those in the contralateral normal hip (P < .05), whereas in the claw-plate group no significant statistical differences were observed between two sides. No or slight limping occurred in 25 patients (81%) in the claw-plate group and 16 patients (48%) in the cable group (P = .007). A multiple logistic regression demonstrated that claw-plate fixation could reduce the incidence of postoperative moderate-to-severe limping. CONCLUSION: Both claw-plate fixation and cable-alone fixation could improve the functional performance of rTHA with ETO, whereas claw-plate fixation could offer superior biomechanical results and gait improvement as compared with cable-alone fixation.

Differences between Two Methods to Stabilize Supramalleolar Osteotomies in Children-A Retrospective Case Series.

Supramalleolar osteotomy (SMO) in pediatric patients can be fixed in various ways. We analyzed the records of 77 pediatric patients (124 SMOs) aged ≤16 years. In 56 patients (96 SMOs), K-wires were used to stabilize SMOs (WF group), while 21 patients (28 SMOs) were treated with locking compression plates (LCPs; PF group). We recorded time to radiographic consolidation, rate of complications, length of hospital stay (LOS), and time to implant removal. Mean time to radiographic consolidation of SMOs was 7.2 weeks in the WF group and 11.1 weeks in the PF group. Complication rate in the WF group was 10.7%. LOS was similar in the two groups (7.0 days in the WF group vs. 7.3 days in the PF group). K-wire stabilization resulted in a shortened interval until consolidation of osteotomies, but children were required to use a cast. Stabilization of SMOs with LCPs facilitated early mobilization and functional rehabilitation with no need to apply a cast. In conclusion, both methods provided safe fixation of SMOs with a low rate of complications. K-wire stabilization combined with a cast achieves fast consolidation of SMOs. We recommend SMO stabilization with angular stable LCPs in patients with muscular weakness or spasticity in whom early mobilization and physiotherapy are necessary to prevent loss of muscle power, muscle function, and bone mass.

Comparison of Haptic and Biometric Properties, Bacterial Load, and Student Perception of Fixative Solutions: Formaldehyde Versus Chilean Conservative Fixative Solution with and without Formaldehyde in Pig Kidneys.

One of the most widely used solutions to fix and preserve organic tissues is formaldehyde, despite reservations regarding its toxicity and the fact that formaldehyde-embalmed bodies lose their original characteristics. Anatomy laboratories have been replacing formaldehyde with solutions that retain the characteristics of fresh tissue. For this purpose, alternative solutions with a very low concentration of formaldehyde or without any formaldehyde have been analyzed. The objective of this study was to compare biometry, coloration, haptic properties, and bacterial load on animal specimens (pig kidneys) embalmed with formaldehyde, and with Chilean Conservative Fixative Solution with and without formaldehyde (formaldehyde chCFS and formaldehyde-free chCFS). Also, the perception of health and biological science students toward specimens treated with different solutions was assessed. The results indicated that there were no significant differences in specimens' retraction, or bacterial load. Students showed a preference for organs embalmed in formaldehyde chCFS and formaldehyde-free chCFS; indicating that with these treatments they could better visualize structures and that the prosections had greater flexibility and the colors were more similar to those of fresh tissue. Additionally, students recommended the material embalmed in formaldehyde chCFS and formaldehyde-free chCFS for anatomy learning. In contrast, students indicated that formaldehyde-fixation negatively affected their practical experience. In conclusion, embalming with formaldehyde chCFS or formaldehyde-free chCFS provides an advantageous practical experience over the use of formaldehyde and may be an alternative to replace the use of formaldehyde in anatomy laboratories.

Treatment of Pathological Humerus-Shaft Tumoral Fractures with Rigid Static Interlocking Intramedullary Nail-22 Years of Experience.

Objective This was a retrospective observational study in patients submitted to intramedullary nail fixation after established or impeding pathological humerus-shaft tumoral fracture in the context of disseminated tumoral disease along 22 years of experience at the same institution. Methods Sample with 82 patients and 86 humeral fixations with unreamed rigid interlocking static intramedullary nail by the antegrade or retrograde approaches. Results The most prevalent primary tumors were breast carcinoma (30.49%), multiple myeloma (24.39%), lung adenocarcinoma (8.54%), and renal cell carcinoma (6.10%). The average surgical time was 90.16 ± 42.98 minutes (40-135 minutes). All of the patients reported improvement in arm pain and the mean Musculoskeletal Tumor Society (MSTS) score rose from 26% in the preoperative period to 72.6% in the evaluation performed in patients still alive 3 months after the surgery. The overall survival was 69.50% 3 months after the surgery, 56.10% at 6 months, 26.70% at 1 year, and 11.90% at 2 years. No death was related to the surgery or its complications. There were only 4 surgery-related complications, 1 intraoperative and 3 late, corresponding to a 4.65% complication risk. Conclusion Closed unreamed static interlocking intramedullary nailing (both in the antegrade or retrograde approaches) of the humerus is a fast, safe, effective, and low morbidity procedure to treat pathological fractures of the humerus shaft, assuring a stable arm fixation and consequently improving function and quality of life in these patients during their short life expectation.

Treatment of Pathological Humerus-Shaft Tumoral Fractures with Rigid Static Interlocking Intramedullary Nail-22 Years of Experience / Tratamento de fraturas patológicas tumorais diafisárias do úmero com haste intramedular rígida bloqueada estática - Experiência de 22 anos

Abstract Objective This was a retrospective observational study in patients submitted to intramedullary nail fixation after established or impeding pathological humerus-shaft tumoral fracture in the context of disseminated tumoral disease along 22 years of experience at the same institution. Methods Sample with 82 patients and 86 humeral fixations with unreamed rigid interlocking static intramedullary nail by the antegrade or retrograde approaches. Results The most prevalent primary tumors were breast carcinoma (30.49%), multiple myeloma (24.39%), lung adenocarcinoma (8.54%), and renal cell carcinoma (6.10%). The average surgical time was 90.16 ± 42.98 minutes (40-135 minutes). All of the patients reported improvement in arm pain and the mean Musculoskeletal Tumor Society (MSTS) score rose from 26% in the preoperative period to 72.6% in the evaluation performed in patients still alive 3 months after the surgery. The overall survival was 69.50% 3 months after the surgery, 56.10% at 6 months, 26.70% at 1 year, and 11.90% at 2 years. No death was related to the surgery or its complications. There were only 4 surgery-related complications, 1 intraoperative and 3 late, corresponding to a 4.65% complication risk. Conclusion Closed unreamed static interlocking intramedullary nailing (both in the antegrade or retrograde approaches) of the humerus is a fast, safe, effective, and low morbidity procedure to treat pathological fractures of the humerus shaft, assuring a stable arm fixation and consequently improving function and quality of life in these patients during their short life expectation.

Resumo Objetivo Estudo retrospectivo observacional em pacientes submetidos à fixação com haste intramedular de fratura patológica tumoral consumada ou iminente da diáfise do úmero em contexto de doença tumoral disseminada ao longo de 22 anos na mesma instituição. Métodos Amostra com 82 pacientes e 86 fixações do úmero com haste intramedular rígida bloqueada estática não fresada anterógrada ou retrógrada. Resultados Os tumores primários mais prevalentes foram carcinoma da mama (30,49%), mieloma múltiplo (24,39%), adenocarcinoma do pulmão (8,54%) e carcinoma das células renais (6,10%). O tempo médio de intervenção cirúrgica para fixação com haste foi 90,16 ± 42,98 minutos (40-135). Todos os pacientes referiram melhoria das queixas álgicas no nível do braço e velicou-semelhoria do scoreMSTSmédio de 26% no pré-operatório para 72,6% na avaliação efetuada nos pacientes ainda vivos aos três meses de pós-operatório. A taxa de sobrevivência aos três meses após a cirurgia foi de 69,50%, 56,10% aos seis meses, 26,70% em um ano e 11,90% em dois anos. Nenhuma dasmortes decorreu da cirurgia ou de complicações dela. Apenas se registaramquatro complicações relacionadas com a cirurgia, uma intraoperatória e três tardias, corresponderam a risco de complicações de 4,65%. Conclusão O uso de haste intramedular não fresada estática bloqueada (anterógrado ou retrógrado) no úmero é um método rápido, seguro, eficaz e com baixa morbilidade no tratamento das fraturas patológicas da diáfise umeral, garante fixação estável do braço e consequentemente melhora a funcionalidade e a qualidade de vida desses pacientes durante a sua curta expectativa de vida.

Comparative evaluation of three methods of skin graft fixation for split thickness skin graft after release of post burn contracture of the neck.

OBJECTIVES: Split thickness skin graft is an essential component of release of post burn contracture of neck. There are many methods of fixation of skin grafts; however, there is lack of objective comparison between different techniques. This study has been designed to compare three commonly used techniques of split thickness skin graft fixation methods. Surgical time, advantages, cost factor and post-operative outcome have been compared amongst three techniques. METHODS: A randomized interventional comparative study was conducted to compare three methods of skin graft fixation in patients of 10-50 years age group, with contracture of more than 3 month duration having more than 100cm2 skin defects after contracture release. Resurfacing of the defects after contracture release was carried out in all the groups using autologous split skin grafts. Patients were included in three groups; Group 1: tie over method, Group 2: skin stapler fixation and Group 3: Cyanoacrylate glue fixation. RESULTS: Mean duration of fixation procedure was 34min in tie over group, in skin stapler group 7min and in cyanoacrylate group 12min. Mean cost of fixation material was 10.23 USD in tie-over group, 11.23 USD in stapler group and 40.06 USD in cyanoacrylate group. Mean score of pain/discomfort (visual analog score) on dressing removal in tie-over group was 3, for skin stapler group was 2.9 and that for cyanoacrylate glue group was 1.8. mean graft take was found to be 90.1% in tie-over group, 94.1% in skin stapler group & 93.8% in cyanoacrylate glue group. On logistic regression analysis, keeping all the variables constant in the groups the complications as the outcome variable, three groups are comparable. The need for regrafting remains inconclusive. CONCLUSIONS: Skin stapler method for skin graft fixation was least time consuming, affordable and highly reliable when graft take success was considered. Cyanoacrylate glue fixation method was least painful and reliable in terms of graft take success though costlier than other two.

Mid-Term Results of Two Different Fixation Methods for Chevron Osteotomy for Correction of Hallux Valgus.

We compared 2 different fixation methods (bioabsorbable pins and cannulated screws) after chevron osteotomy for the treatment of hallux valgus. We reviewed consecutive proximal chevron osteotomies in 80 patients (100 feet) performed by 2 surgeons. Of the 100 feet (80 patients), 48 feet (40 patients) were stabilized with bioabsorbable pins, and 52 feet (40 patients) were stabilized with cannulated screws. In the pin group, 8 patients were male (20%) and 32 were female (80%). In the screw group, 10 patients were male (25%) and 30 were female (75%). The mean patient age was 43.1 (range 24 to 60) years in the pin group and 43.5 (range 20 to 60) years in the cannulated screw group. The visual analog scale, intermetatarsal angle, and hallux valgus angle decreased significantly and the American Orthopaedic Foot and Ankle Society scores increased significantly in all patients in both groups after surgery (p < .05). No statistically significant differences were found between the 2 groups (p > .05). Both fixation methods were found to be safe and reliable under the appropriate conditions and when performed by an experienced surgeon.

Silicon nanoparticles coated with an epitope-imprinted polymer for fluorometric determination of cytochrome c.

The authors describe a composite consisting of silicon nanoparticles that were first coated with SiO2 and then with a molecularly imprinted polymer (SiNP@SiO2@MIP). The MIP was generated by dual epitope imprinting such that it can recognize cytochrome c (Cyt c). The MIP on the NPs was prepared from the functional monomer zinc(II) acrylate (ZnA), the crosslinker ethylene glycol dimethacrylate and the initiator 2,2'-azoisobutyronitrile. Dual epitope templates for Cyt c included (a) a C-terminal nonapeptide (AYLKKATNE), and (b) an N-terminal nonapeptide (GDVEKGKKI). The chelation between Zn(II) of ZnA and the amino groups or hydroxy groups of the template nonapeptides warrants good recognition and capture of Cyt c. The fluorescence originating from SiNPs has excitation/emission peaks at 360/480 nm and is quenched by Cyt c in the 0.50-40.0 µM concentration range. The correlation coefficient for the calibration plot of the imprinted NPs is 0.9937. The detection limit is 0.32 ± 0.01 µM, the precisions of six replicate detections at levels of 0.5, 20 and 40 µM Cyt c are 3.2, 2.7 and 2.8%, respectively, and the imprinting factor is 2.43. Compared to single epitope template imprinting, dual epitope imprinting results in improved selectivity. The imprinted nanoparticles can discriminate Cyt c even if one amino acid is mismatched. The method was applied to the determination of Cyt c in spiked diluted human serum and gave recoveries between 94.0 and 107.5%. Graphical Abstract A fluorescent material of the architecture silicon nanoparticle@SiO2@molecularly imprinted polymer (SiNP@SiO2@MIP) was fabricated by dual epitope imprinting and a metal-chelating method. The chelation between Zn(II) of the functional monomer zinc(II) acrylate and the amino groups or hydroxy groups of template warrants that the material recognizes and captures cytochrome c well, and this results in fluorescence quenching.

Arthroscopy-assisted versus standard intramedullary nail fixation in diaphyseal fractures of the humerus.

PURPOSE: The aim of this study was to assess applicability of arthroscopic technique in intramedullary nail fixation of humerus shaft fractures and to compare with conventional nailing in terms of its effects on perioperative and postoperative intra-articular complication rates as well as on clinical and functional outcomes. METHODS: This prospective randomized controlled clinical trial included 40 patients (12 females and 28 males) indicated for surgery between either undergo arthroscopy-assisted (Arthroscopy-assisted intramedullary nailing [AIMN]; n = 20) or conventional (Intramedullary nailing [IMN]; n = 20) anterograde intramedullary nailing. Two groups were compared in terms of mean number of fluoroscopic shootings until the guide wire was inserted, time for union, length of hospital stay, and complication rates. Shoulder functions were assessed by Constant and American Shoulder and Elbow Surgeons (ASES) score. RESULTS: Groups did not significantly differ in terms of age, gender, and mechanism of injury, length of hospital stay, union rate, and mean union time ( p > 0.05). Mean ASES and Constant scores were found to be statistically significantly higher in AIMN group than that in IMN group ( p = 0.000 and p = 0.002, respectively). Mean number of fluoroscopic shootings until the guide wire was inserted was 2.15 in AIMN group, which was significantly lower compared to 4.2 of IMN group ( p = 0.000). CONCLUSIONS: Arthroscopy-assisted technique may be an applicable and safe method owing to its cosmetic advantages and more satisfactory postoperative shoulder functions subsequent to less injury to deltoid, rotator cuff, and other soft tissue, as compared to conventional anterograde approach.

Evaluation of four mesh fixation methods in an experimental model of ventral hernia repair.

BACKGROUND: The present animal study was conducted to comparably investigate the performance of four different fixation techniques of intraperitoneally implanted meshes. MATERIALS AND METHODS: Fifteen New Zealand white rabbits were used. In each animal, four abdominal wall defects were created and repaired with four pieces of intraperitoneal mesh (Parietex Composite), fixed with nonabsorbable (titanium) spiral tacks (group A), absorbable (lactic and glycolic acid co-polymer) screw-type tacks (group B), transfascial polypropylene sutures (group C), or fibrin glue (group D). Adhesion formation, mesh shrinkage, tensile strength, and host tissue response were evaluated at 90 d. RESULTS: Adhesions were observed in all groups, and differences were not significant. The percentage of shrinkage was higher in group C (26.91%), lower in group D (12%), whereas in groups A and B, the mean shrinkage was 20.17% and 23.33%, respectively (P = 0.032). The incorporation of mesh fixation element to the abdominal wall was 9.18 ± 3.91 N, 6.96 ± 3.0 N, 13.68 ± 5.38 N, and 2.57 ± 1.29 N, in groups A, B, C, and D, respectively (P < 0.001). Regarding local inflammatory response and foreign body reaction, no difference was observed between groups. However, with respect to fibrous tissue presence, its quantity was clearly less in group D compared with the other groups (P < 0.001). CONCLUSIONS: None of the examined fixation techniques proved to be ideal. Probably, the best way to fixate an intraperitoneally implanted mesh may be achieved using a combination of the studied materials. Prospective randomized trials are needed to confirm the superiority of the combined use of different fixation devices in clinical practice.

Optimization of fixation methods for image analysis of the hepatopancreas in whiteleg shrimp, Penaeus vannamei (Boone).

Pathology in penaeid shrimps relies on histology, which is subjective, time-consuming and difficult to grade in a reproducible manner. Automated image analysis is faster, objective and suitable for routine screening; however, it requires standardized protocols. The first critical step is proper fixation of the target tissue. Bell & Lightner's (A Handbook of Normal Penaeid Shrimp Histology, 1988, The World Aquaculture Society, Baton Rouge) fixation protocol, widely used for routine histology of paraffin sections, is not optimized for image analysis, and no protocol for frozen sections is described in the available literature. Therefore, the aim of this study was to optimize fixation of the hepatopancreas (HP) from whiteleg shrimp (Penaeus vannamei) for both paraffin and frozen sections using a semiquantitative scoring system. For paraffin sections, four injection volumes and three injection methods were compared, for frozen sections, four freezing methods and four fixation methods. For paraffin sections, optimal fixation was achieved by increasing threefold the fixative volume recommended by Bell and Lightner, from 10% to 30% of the shrimp body weight, combined with single injection into the HP. Optimal fixation for frozen sections was achieved by freezing the cephalothorax with liquid nitrogen, followed by fixation of the section with 60% isopropanol. These optimized methods enable the future use of image analysis and improve classical histology.