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Abstract Objective To evaluate the biomechanical capacity of two forms of fixation for Pipkin type-II fractures, describing the vertical fracture deviation, the maximum and minimum principal stresses, and the Von Mises equivalent stress in the syntheses used. Materials and Methods Two internal fasteners were developed to treat Pipkin type-II fractures through finite elements: a 3.5-mm cortical screw and a Herbert screw. Under the same conditions, the vertical fracture deviation, the maximum and minimum principal stresses, and the Von Mises equivalent stress in the syntheses used were evaluated. Results The vertical displacements evaluated were of 1.5mm and 0.5mm. The maximum principal stress values obtained in the upper region of the femoral neck were of 9.7 KPa and 1.3 Kpa, and the minimum principal stress values obtained in the lower region of the femoral neck were of-8.7 KPa and -9.3 KPa. Finally, the peak values for Von Mises stress were of 7.2 GPa and 2.0 GPa for the fixation models with the use of the 3.5-mm cortical screw and the Herbert screw respectively. Conclusion The fixation system with the Herbert screw generated the best results in terms of reduction of vertical displacement, distribution of the maximum principal stress, and the peak Von Mises equivalent stress, demonstrating mechanical superiority compared to that of the 3.5-mm cortical screw in the treatment of Pipkin type-II fractures.

ABSTRACT Objective: To determine, by biomechanical analysis, safe patellar cut limits in anterior cruciate ligament (ACL) reconstruction that minimize fracture risks. Methods: From three-dimensional reconstruction, triangular cuts were made in the patella, with a depth of 6.5 mm and variable width and length (10 to 20 mm and 8 to 12 mm, respectively, both with an interval of 1 mm). The combinations of cuts constituted 55 models for tests, with five variations in width and 11 variations in length, tested with the finite element method (FEM). Results: The mean of the localized principal maximum (traction force) values was 4.36 Pa (SD 0.87 ± 0.76) and the localized principal minimum (compression force) was −4.33 Pa (SD 1.05 ± 1.11). Comparing width and length to the tension force of the values of the main maximum, we found statistical significance from 11 mm for width and 13 mm for length. Conclusion: In ACL reconstruction, the removal of the patellar bone fragment is safe for fragments smaller than 11 mm in width and 13 mm in length, which corresponds to 24% of the width and 28% of the length of the patella used. Level of Evidence II, Comparative Prospective Study.

ABSTRACT Objective: To compare the application of partial meniscectomy concomitant with primary ACL reconstruction, using the graft from the patellar tendon with individuals who underwent only ACL reconstruction, in clinical functional criteria and degree of osteoarthritis (OA), after 10 years of the surgical process. Methods: This is a retrospective cross-sectional study with 37 patients who underwent ACL reconstruction with a graft from the patellar tendon, associated or not with partial meniscectomy, divided into 2 groups: with meniscal injury (n = 22) and without meniscal injury (n = 15). Anthropometric data and four outcome measures were used to analyze the results: SF-36 questionnaire, arc of motion assessment, Knee injury and Osteoarthritis Outcome Score (KOOS), and Ahlbäck Radiographic Classification. Results: No differences were found for health-related quality of life, arc of motion, functional condition and knee OA severity/grade in patients who underwent partial or no meniscectomy in conjunction with ACL reconstruction (p > 0.05). Conclusion: Participants who underwent partial meniscectomy in conjunction with primary ACL reconstruction with a graft from the patellar tendon, after 10 years of the surgical process, showed no significant differences in the clinical functional criteria and severity of knee OA, compared to individuals who underwent only ACL reconstruction. Level of Evidence II, Prognostic study.

Abstract Objective The present study aims to analyze the intra- and interobserver reproducibility of the Lauge-Hansen, Danis-Weber, and Arbeitsgemeinschaft für Osteosynthesefragen (AO) classifications for ankle fractures, and the influence of evaluators training stage in these assessments. Methods Anteroposterior (AP), lateral and true AP radiographs from 30 patients with ankle fractures were selected. All images were evaluated by 11 evaluators at different stages of professional training (5 residents and 6 orthopedic surgeons), at 2 different times. Intra- and interobserver agreement was analyzed using the weighted Kappa coefficient. Student t-tests for paired samples were applied to detect significant differences in the degree of interobserver agreement between instruments. Results Intraobserver analysis alone had a significant agreement in all classifications. Moderate to excellent interobserver agreement was highly significant (p ≤ 0.0001) for the Danis-Weber classification. The Danis-Weber classification showed, on average, a significantly higher degree of agreement than the remaining classification systems (p ≤ 0.0001). Conclusion The Danis-Weber classification presented the highest reproducibility among instruments and the evaluator's little experience had no negative influence on the reproducibility of ankle fracture classifications. Level of Evidence II, Diagnostic Studies - Investigating a Diagnostic Test.

Abstract Objective The present study aims to identify the energy required for synthetic proximal femoral fracture after removal of three implant types: cannulated screws, dynamic hip screws (DHS), and proximal femoral nail (PFN). Methods Twenty-five synthetic proximal femur bones were used: 10 were kept intact as the control group (CG), 5 were submitted to the placement and removal of 3 cannulated screws in an inverted triangle configuration (CSG), 5 were submitted to the placement and removal of a dynamic compression screw (DHSG), and 5 were submitted to the placement and removal of a proximal femur nail (PFNG). All samples were biomechanically analyzed simulating a fall on the greater trochanter using a servo-hydraulic machine to determine the energy (in Joules [J]) required for fracture. Results All samples presented basicervical fractures. The energy required for fracture was 7.1 J, 6.6 J, 6 J, and 6.7 J for the CG, CSG, DHSG and PFNG, respectively. There was no statistically significant difference (considering a 95% confidence interval) in energy among the study groups (p = 0.34). Conclusion There was no statistically significant difference in the energy required to cause a synthetic proximal femoral fracture after removing all three implant types and simulating a fall over the greater trochanter.

ABSTRACT Objective: This study aims to describe a simple and accurate semiological method executing a specific maneuver with the lower limb to direct the semiological investigation towards the tendinopathies in the gluteus medius and minimus. Methods: Fifty patients participated in the study, with a mean age of 44.1 ± 13 years, with persistent pain on the side of the hip for more than three months. To compare the FABREX (proposed test) and Lequesne semiological tests, in the diagnosis of tendinopathies in the gluteus medius and minimus, Magnetic Resonance Imaging (MRI) was adopted as the gold standard. Results: FABREX presented high sensitivity and moderate specificity for tendinopathy in the gluteus medius and high sensitivity and specificity for tendinopathy in the gluteus minimus. Conclusion: The proposed test, when positive, can be used to determine the diagnosis of gluteal tendinopathies (high specificity). Moreover, it has high sensitivity, excluding the diagnosis when negative. This study represents the initial step for validating the FABREX test, and can therefore be considered a simple and accurate procedure to identify patients with or without gluteal tendinopathies. Level of Evidence III, Case Control Study.

Abstract Background The biomechanical behavior of Pauwels type III fractures should be taken into consideration when performing internal fixation, since this repair should resist the shear force inherent in the vertical fracture line to the greatest extent possible. Recently, the use of a small fragment plate on the medial face of the femoral neck has been proposed by some authors, with satisfactory initial results. In the current study we analyze the mechanical role a medial plate used as a buttress plate for Pauwels type III femoral neck fractures, comparing the resistance of two fixation configurations using three cannulated screws. Methods Pauwels type III fractures were simulated in synthetic bones models and two groups were created, one of those using two parallel screws at the bottom of the femoral neck and the third screw crossing the fracture horizontally (G1), and the other fixed in the same arrangement as G1, but with the addition of a medial side plate at the apex of the fracture (G2). The constructs were subjected to axial loading until catastrophic failure. Results The addition of a medial plate buttressing the femoral neck increased significantly the resistance to maximum loading (p = 0.003). Conclusion Use of a medial buttress plate results in a mechanically superior construction for Pauwels type III fractures fixed with multiple cannulated screws. Lebel of evidence Level IV. Biomechanical comparative study.

ABSTRACT Objective: To evaluate the mechanical behavior of the proximal end of the femur submitted to the X-shaped polymethylmethacrylate (PMMA) reinforcement technique. Methods: Fifteen synthetic femurs, with a Nacional® density of 10 PCF, were divided into two groups: the DX group, with 5 units that were submitted to PMMA reinforcement, and the DP group, with 10 units, which were evaluated intact. The volume of PMMA required, the maximum load, and the absorbed energy to fracture were analyzed by means of a static mechanical bending test simulating a fall on the greater trochanter. Results: A mean of 6 ml of PMMA was used to model the X-reinforcement; it was observed that the DX group presented significantly higher maximum load (median = 1553 N, p = 0.005) and absorbed energy to fracture (median = 9.7 J; p = 0.050) than the DP group (median = 905 N and 6.6 J). Conclusion: X-reinforcement of the proximal end of synthetic femurs showed a statistically significant increase in the maximum load and absorbed energy to fracture in the mechanical assay when compared to the control group. Level of Evidence III, Experimental study.

ABSTRACT Objectives To analyze the results of biomechanical assays of the fixation of Pauwels type II femoral neck fractures in synthetic bones, using two parallel cannulated screws or three cannulated screws in an inverted pyramid formation. Methods Ten Brazilian-made synthetic bones were divided into 2 groups. Groups A and B utilized three and two cannulated screws, respectively, after osteotomy in the middle third of the femur, perpendicular to the axis of the femoral neck, simulating a Pauwels type II femoral neck fracture. The resistance of these fixations was analyzed by compression on the axis of the force resulting from hip compression, simulated with a manual hydraulic press. The T-test and post hoc analysis were used to compare the groups, and the significance criterion adopted was p < 0.05. Results In group A, which used fixation with three screws, synthesis failure was seen at a mean force of 526 N. In group B, which used two screws, the mean force was 466 N. The results presented a statistically significant difference (p = 0.02). Conclusion The osteosynthesis of femoral neck fractures in synthetic bone fixated with two screws presented inferior results to fixation with three screws. Level of Evidence III; Case-control study.

ABSTRACT Objective: To conduct a systematic review of literature about the use of contralateral patellar tendon autograft in anterior cruciate ligament reconstructions and present the results. Methods: The LILACS, MEDLINE, Cochrane, PubMed, Scielo and Google Scholar databases were searched without date restrictions for the keywords “anterior cruciate ligament reconstruction” combined with “contralateral” in the article title. After the studies were identified, two independent evaluators collected the qualitative characteristics of the studies and classified them according to clinical outcomes of these grafts as positive, neutral, or negative. Results: A total of 755 articles were found initially, and after detailed evaluation of all references, followed by a screening process and assessment of quality, a total of 11 studies were determined to be eligible for inclusion in this systematic review. Of these, 72.72% were level II studies, the most common level of evidence among the results. Positive results for this type of graft were found in 63.63% of the studies. Conclusion: Based on the literature review, most of the included articles (63.63%) presented positive results for the use of contralateral patellar tendon grafts. Level of Evidence III; Systematic review.

ABSTRACT Objectives: To compare the results of a simulated fall on the greater trochanter in the proximal portion of a synthetic femur before and after femoral reinforcement with tricalcium phosphate bone cement (TP) and polymethyl methacrylate (PMMA), using finite element analysis (FEA). Methods: Using two synthetic proximal femurs, a FEA simulating a fall on the greater trochanter was performed, using the Bi-directional Evolutionary Structural Optimization (BESO) program. For this analysis, the femurs were filled with TP and PMMA after perforations were created in the trochanteric region and neck. The results were compared with the strength values obtained from testing the control specimen, a synthetic bone without reinforcement. Results: FEA showed a value of 600 N prior to reinforcement. After cementing with PMMA, the load increased by 57.5% (945 N), and by 53% (920 N) after cementing with TP. Conclusion: Synthetic femurs gained resistance to fracture-causing forces in a simulated fall on the trochanter after bone reinforcement with PMMA and TP. Level of Evidence III; Experimental study.

ABSTRACTS The apophyseal fracture or avulsion of the greater trochanter occurs in skeletally immature patients. It has at etiological factors indirect mechanisms (avulsion) and direct mechanisms (trauma on the trochanter), the latter being the most common. The clinical presentation is easily identified and a simple X- ray can confirm the diagnosis. Regardless of the treatment chosen, this pathology has a high correlation with osteonecrosis of the femoral head, even as a rare fact, however with innocent appearance, on this pathology.

Objective:To statistically analyze the results obtained from biomechanical tests on fixation of femoral neck fractures of Pauwels III type, in synthetic bone, using the dynamic hip system with an anti-rotation screw, versus a control group.Methods:Ten synthetic bones from a Brazilian manufacturer (model C1010) were used and divided into two groups: test and control. In the test group, fixation of an osteotomy was performed with 70° of inclination at the level of the femoral neck, using DHS with an anti-rotation screw. The resistance of this fixation was evaluated, along with its rotational deviation at 5 mm of displacement (phase 1) and at 10 mm of displacement (phase 2), which was considered to be failure of synthesis. In the control group, the models were tested in their entirety until femoral neck fracturing occurred.Results:The test values in the test group (samples 1-5) in phase 1 were: 1512N, 1439 N, 1205 N, 1251N and 1273 N, respectively (mean = 1336 N; standard deviation SD] = 132 N). The rotational deviations were: 4.90°, 3.27°, 2.62°, 0.66° and 0.66°, respectively (mean = 2.42°; SD = 1.81°). In phase 2, we obtained: 2064 N, 1895 N, 1682 N, 1713 N and 1354 N, respectively (mean = 1742 N; SD = 265N). The failure loading values in the control group were: 1544 N, 1110 N, 1359 N, 1194 N and 1437 N, respectively (mean = 1329 N; SD = 177N). The statistical analysis using the Mann-Whitney test showed that the test group presented maximum loading at a displacement of 10 mm, i.e. significantly greater than the failure loading of the control group (p = 0.047).Conclusion:The mechanical resistance of the test group was significantly greater than that of the control group.

Objective: To analyze statistically results in biomechanical testing of fixation of femoral neck Pauwels type III fractures, on synthetic bone, with dynamic condylar screw (DCS) and control group.Methods: Ten synthetic bones of a national brand were used. Test Group: fixation was performed after osteotomy at 70o tilt using DCS plate with four holes. We analyzed the resistance of this fixation with 5 mm displacement and rotational deviation (Step 1) and with10 mm (Step 2). Control group: the models were tested in their integrity until the femoral neck fracture occurred.Results: The values of the test group in Step 1 showed a mean of 974N and SD = 114N. In Stage 2, we obtained on average 1335N and SD = 98N. The values in the control group were: 1544N, 1110N, 1359N, 1194N, 1437N, respectively. Statistical analysis using the Mann-Whitney test for comparison of the maximum force (N) between the test group and the control, in Step 2, demonstrated that there is no significant difference between the DCS and control plates (p = 0.91).Conclusion: There is no significant difference between the DCS boards and the control group exposed to full resistance. Level of Evidence III, Case Control.

OBJECTIVE: To analyze the results of biomechanical assays of fixation of Pauwels type III femoral neck fracture in synthetic bone, using 7.5mm cannulated screws in inverted triangle formation, in relation to the control group. METHODS: Ten synthetic bones were used, from a domestic brand, divided into two groups: test and control. In the test group, a 70° tilt osteotomy of the femoral neck was fixated using three cannulated screws in inverted triangle formation. The resistance of this fixation and its rotational deviation were analyzed at 5mm displacement (phase 1) and 10mm displacement (phase 2). The control group was tested in its integrity until the fracture of the femoral neck occurred. The Mann-Whitney test was used for group analysis and comparison. RESULTS: The values in the test group in phase 1, in samples 1-5, showed a mean of 579N and SD =77N. Rotational deviations showed a mean of 3.33°, SD = 2.63°. In phase 2, the mean was 696N and SD =106N. The values of the maximum load in the control group had a mean of 1329N and SD=177N. CONCLUSION: The analysis of mechanical strength between the groups determined a statistically significant lower value in the test group. Level of Evidence III, Control Case.

OBJECTIVE: To analyze statistically results obtained between biomechanical assays on fixation of femoral neck fracture type Pauwels III, on synthetic bone, using 7.5 mm non parallel cannulated screws and control group. METHODS: Ten synthetic bones from a national brand were used. Test group: fixation of 70(o) tilt femoral neck osteotomy was performed using three 7.5 mm non parallel cannulated screws. We analyzed the resistance of this fixation with 5 mm of displacement, and rotational deviation (phase 1) and with 10 mm offset (phase 2). Control group: the models were tested in their integrity until the femoral neck fracture occurred. RESULTS: the values of the test group in phase 1, in sample 1-5 had a mean of 517N and SD = 96N. Rotational deviations showed a mean of 3.79° e SD = 2. 03°. In phase 2, mean was 649N and SD = 94N. The values of the maximum load in the control group were: 1544N, 1110N, 1359N, 1194N, 1437N; respectively. Statistical analysis between the groups showed a statistically significant lower value in the test group. CONCLUSION: the analysis of mechanical resistance between the groups has determined statistically significant value for the test group. Level of Evidence III, Case-control Study.

OBJETIVO: Avaliar in vitro a resistência mecânica do DHS-AF®. MÉTODOS: Foi avaliado in vitro a resistência de um parafuso deslizante modificado pelo acréscimo de um sistema conector, o DHS-AF®. RESULTADOS: A modificação realizada pelos autores permite a troca do parafuso deslizante, sem que obrigatoriamente o cirurgião tenha que retirar a placa e desmontar todo o dispositivo para reposicioná-lo adequadamente. Foi realizado um ensaio de flexão estático para avaliação da força máxima, rigidez e ductilidade deste sistema. O DHS-AF® apresentou características mecânicas satisfatórias quando comparado a outros dispositivos convencionais que utilizam o mesmo princípio. CONCLUSÃO: Baseados nesses resultados, os autores propõem a utilização desse novo implante em futuros estudos in vivo. Nível de Evidência III, Estudo Analítico.

OBJETIVO: Avaliar isolada e comparativamente medidas do conjunto guia excêntrico-placa utilizado no material de 4.5mm e determinar sua influência na força de compressão. MÉTODOS: Foram utilizados quatros guias excêntricos e quatro placas largas de compressão dinâmica (DCP-L) de quatro fabricantes nacionais e um paquímetro digital Vonder®. Criou-se medidas-padrão para os conjuntos, totalizando cinco parâmetros, identificados de A a E. Os conjuntos foram formados por materiais da mesma fábrica e identificados de I a IV. As análises foram feitas com a visualização volar dos guias inseridos nas placas. As placas foram ensaiadas em máquina universal de ensaios. RESULTADOS: Os conjuntos I, II, apresentaram os mesmos valores em todas as medidas. Todos os conjuntos apresentaram os mesmos valores de E = 8.15 e B = 3.60. O conjunto III: A= 8.10mm, C=3.25mm e D= 1.25mm. O conj. IV: A = 7.00mm, C=3.10mm, D = 0.30mm. O conj. I apresentou Força de compressão máxima (F Max.) 80.58 N, conj. II: F Max. 81.63 N, conj. III: F Max. 36.32N, conj. IV: F Max. 37.52N. CONCLUSÃO: As medidas avaliadas nos conjuntos denotam a falta de padronização na fabricação de instrumentais ortopédicos e sua consequência nos valores da força de compressão. Nível de evidência III, estudo analítico.OBJECTIVE: To carry out isolated and comparative evaluations of the measurements of the set eccentric guide plates used in 4.5mm surgical implants, and to determine the effect of these measurements on compression strength. METHODS: Four eccentric guides, (or guide plates?) four large dynamic compression plates (L-DCP) from four local manufacturers, and a Vonder® 200 mm caliper brand were used. Five standard parameter measurements were created for the set eccentric guide-plate, which were identified as A to E. Four sets were made, using materials of the same factory, and identified as groups I to IV. The analyses were performed by measuring all the parameters from a ventral view of the plate, with the eccentric guide placed in the plate hole. RESULTS: Groups I and II showed the same values for all the parameters. All the groups showed the same measurements for E = 8.15 e B = 3.60. Group III: A = 8.10mm, C = 3.25mm, D = 1.25mm. Group IV: A = 7.00mm, C = 3.10mm, D = 0.30mm. Maximum compression force was (F Max.): Group I 80.58 N, Group. II: F Max. 81.63 N, Group. III: F Max. 36.32N, Group. IV: F Max. 37.52N CONCLUSION: The measurements evaluated show a lack of standardization in the manufacture of orthopedic instruments and its effects on the values for compression strength. Level of Evidence: Level III, analytical study.

OBJETIVO: Descrever através de estudo em cadáver a disposição anatômica do terço proximal da artéria cincunflexa femoral medial (ACFM). MÉTODOS: Foi avaliada a disposição anatômica do terço proximal da ACFM, através de dissecção em 12 quadris de cadáver, que após terem sua altura aferida em metros (M), foram determinados alguns parâmetros: Ângulo de lateralização da ACFM (Â), Profundidade da ACFM em relação a origem superomedial do músculo quadrado femoral (P), distância da ACFM em relação a inserção superolateral do músculo quadrado femoral (D). RESULTADOS: Quando comparamos a média dos parâmetros entre os sexos notamos: Masculino Â= 43.6 graus, feminino Â= 38.3 graus. Masculino D= 6mm, feminino D= 9.5mm. Masculino P= 20.8 mm, feminino P= 18.3mm. A média dos parametros  e P são menores no sexo feminino porém o parâmetro D no sexo feminino é maior. CONCLUSÃO: Devemos ter como parâmetro superficial de segurança para o terço proximal da ACFM o ponto de inserção superolateral do músculo quadrado femoral. Que o parâmetro D da ACFM no sexo feminino é maior do que no sexo masculino. Que desinserir o músculo quadrado femoral em sua origem no ísquio pode oferecer maior segurança a ACFM do que faze-lo em sua inserção femural. Nível de evidência IV, série de casos.OBJECTIVE: To describe, in a cadaver study, the anatomical arrangement of the proximal third medial femoral circumflex artery (ACFM). METHODS: We evaluated the anatomic arrangement of the proximal third of the ACFM through dissection in 12 cadaver hips. After measuring their height in meters (M), several parameters were determined: angle of lateralization of ACFM (Â), Depth ACFM in relation to the superomedial origin of the quadratus femoris muscle (P), and distance of ACFM from the superolateral insertion of the muscle quadratus femoris (D). RESULTS: In the comparison of mean parameters between the sexes, it was noted that: Male  = 43.6 degrees, female  = 38.3 degrees. Male D = 6mm, female D = 9.5mm. Male P = 20.8 mm, female P = 18.3mm. The average for parameters A and P were lower in females, but parameter D was higher in females. CONCLUSION: We should use, as the secure surface parameter for the proximal third of the ACFM, the superolateral insertion point of the quadratus femoris muscle. The fact that the parameter D of ACFM is greater in females than in males. Disconnecting the quadratus femoris muscle at its point of origin in the isquio may offer greater security to ACFM than doing it at the point of femoral insertion. Level of Evidence.

OBJETIVO: Apresentar os resultados obtidos em ensaios de aplicabilidade de uma placa do tipo sistema dinâmico do quadril modificado, que permite a manipulação ou troca do parafuso deslizante, sem que haja necessidade da retirada de todo o sistema. MÉTODO: Foram utilizadas cinco placas do tipo sistema dinâmico do quadril modificado (DHS- AFpat.req.), fabricadas por uma empresa nacional, produzidas em aço inoxidável austenítico ASTM F 138, com quatro furos e ângulo de 135o, as quais foram aplicadas a cinco segmentos de osso sintético de fêmur proximal da marca Synbone. Todos os implantes foram fixados ao osso sintético, seguindo as técnicas cirúrgicas descritas pela fundação AO (Arbeitsgemeinschaft für Osteosynthesefragen). RESULTADOS: Todas as placas do sistema dinâmico do quadril modificado (DHS-AF) permitiram facilidade na manipulação e a troca do pino deslizante sem a necessidade de retirada da placa. CONCLUSÃO: Os testes in vitro de aplicabilidade do DHS-AF nos forneceram resultados promissores e nos levaram a acreditar que, após avaliações biomecânicas, para confirmar a sua segurança, podem ser reproduzidos in vivo.OBJECTIVE: This report considers the results of the applicability test of a modified dynamic hip system developed by the authors, which allows either the manipulation or the exchange of the sliding screw, without the need to remove the plate and take all the system apart in order to change its size or position. METHODS: Five modified plates - DHS-AF - manufactured with austenitic stainless steel ASTM F 138, with 4 holes and a 135o angle were inserted in five segments of synthetic bone of proximal femur (Synbone). All implants were fixed to the femur following the surgical techniques described by AO foundation (Arbeitsgemeinschaft für Osteosynthesefragen). RESULTS: The modified dynamic hip system (DHS-AF) allowed ease in handling and exchange of sliding screw without the need for plate removal. CONCLUSION: In vitro test of the applicability of DHS-AF afforded promising results and led us to believe that after biomechanical evaluation to confirm its safety it may be reproduced in vivo.

OBJETIVO: Avaliar comparativamente a força de tração (F) determinada com a utilização de parafuso excêntrico em placas do tipo compressão dinâmica larga (DCP-L). MÉTODOS: Foram utilizadas três placas de tipo DCP-L de quatro fabricantes nacionais, todas em aço inoxidável austenítico ASTM F 138, e instrumentais disponíveis nas caixas de 4.5mm. As placas foram fixadas a dois corpos de prova sintéticos de polietileno e a força de tração foi obtida pela utilização de parafuso de 4.5mm, introduzido em furo excêntrico, realizado com instrumentais específicos de cada fabricante. Os resultados foram obtidos por uma máquina servo-hidráulica BME 2000 160/AT, Brasválvula. Os implantes foram divididos em grupos. (Fab. I, II, III, IV). Os testes foram interrompidos após atingir uma força de aperto do parafuso excêntrico de 5 N. RESULTADOS: O grupo I apresentou média de Força máxima (F Max.) 80.58 N; grupo II: F Max. 81.63 N; Grupo III: F Max. 36.32N; Grupo IV: F Max. 37.52N. Utilizando a Análise de Variância de Krukal-Wallis (ANOVA não paramétrica), sendo p= 0,05 existe diferença significativa na força máxima entre os grupos (p = 0,039). CONCLUSÃO: As placas DCP-L do grupo II apresentaram maior força (N) com fixação da placa utilizando parafuso excêntrico. Nível de Evidência: Nível III, estudo analítico.OBJECTIVE: To comparatively evaluate traction force (F) determined with the use of the eccentric screw in large compression dynamic plates (DCP-L). METHODS: Three DCP-L plates were used, from four national manufacturers, all in austenitic stainless steel ASTM F 138, and instruments available in boxes of 4.5mm. The plates were attached to two specimens of synthetic polyethylene, and traction force was applied using a 4.5mm screw inserted into the eccentric hole, using instruments specific to each manufacturer. The results were obtained by a servo-hydraulic machine BME 2000 160/AT, Brasválvula. The implants were divided into groups. (Fab I, II, III, IV). The tests were stopped after reaching a pinch force of the load screw of 5 N. RESULTS: Group I had a mean peak force (F Max) of 80.58 N; Group II: F Max 81.63 N; Group III: F Max 36.32N; and Group IV: F Max 37.52N. Using Krukal-Wallis Analysis of Variance (ANOVA non-parametric), where p = 0.05, there was a significant difference in maximum strength between the groups (p = 0.039). CONCLUSION: Plates DCP-L of group II showed greater strength (N) with plate fixation using the eccentric screw. Level of Evidence: Level III, analytical study.

OBJETIVO: Avaliar a relação entre lesões abdominais e a introdução de fios guia em ensaios cirúrgicos do quadril, propor um sistema de escorização e conduta médica em função da distância percorrida pelo fio guia a partir da placa quadrilátera e a estrutura anatômica lesionada. MATERIAL E MÉTODOS: Utilizou-se 18 quadris de cadáveres, um fio de Steimann de 3.2 x 300 mm, um perfurador elétrico e um paquímetro. Introduziu-se o fio no centro do colo femoral por via de acesso lateral no quadril sob visualização direta. Por via de acesso abdominal mediana longitudinal estendida à região pélvica, observou-se a placa quadrilátera até o fio a transfixar. A partir deste ponto, prolongou-se a inserção por mais 140 mm, a fim de observar seu trajeto abdominal e descrever as lesões apresentadas em função da distância percorrida. RESULTADOS: Houve cinco (27%) lesões de cólon sigmóide e uma (5%) lesão transfixante do nervo obturador. Artérias e veias ilíacas comuns contra laterais ao quadril fixado não foram lesionadas. CONCLUSÃO: O fio guia não deve ultrapassar a placa quadrilátera. Medidas de prevenção são importantes no pré e intra-operatório e o escore e a conduta médica propostos neste estudo devem ser criteriosamente observados nos casos de lesão comprovada.OBJECTIVES: Evaluate the relationship between abdominal injuries and the introduction of guide wire in experimental hip surgery, to propose a scoring system and a medical management based on the distance traveled by the guide wire from the quadrilateral plate until the damaged anatomical structure. MATERIAL AND METHODS: 18 cadaveric hips, a Steimann pin of 3.2 x 300mm, an electric drill and a caliper were used. The wire was inserted in the center of the femoral neck through a lateral approach in the hip under direct visualization. Via median abdominal extended approach to the pelvic region, the quadrilateral plate was observed until the wire crossed it. From this point the wire was further inserted 140 mm in order to observe its abdominal path and describe the lesions presented based on the distance traveled. RESULTS: There were five lesions (27%) in the sigmoid colon, and one transfixing injury (5%) of the obturator nerve. The common iliac arteries and veins from the contralateral hip were not injured. CONCLUSION: The guide wire must not exceed the quadrilateral plate. Preventive measures are important in the pre- and intra-operatory stages and the score and medical management proposed in this study should be carefully observed in cases of injury.

OBJETIVO: Avaliar isolada e comparativamente placas do tipo sistema dinâmico do quadril (DHS) de dois fabricantes nacionais, analisar estatisticamente seus resultados e demonstrar a falta de determinantes para sua fabricação. MÉTODOS: Foram realizados ensaios estáticos de flexão em cinco placas DHS do fabricante I (grupo I) e em igual quantidade do mesmo modelo do fabricante II (grupo II), sendo todas fabricadas em aço inoxidável austenítico ASTM F 138, com quatro furos e angulação de 135º. Utilizou-se máquina servohidráulica MTS, modelo Test Star II®, com capacidade de carga de 10 toneladas e controle de deslocamento. Foram obtidos dados da carga aplicada (P) em função do deslocamento vertical do pistão (L), cuja velocidade foi 5 mm/min. Os ensaios foram interrompidos após atingir a deflexão vertical máxima especificada pelas normas dos ensaios. RESULTADOS: Grupo I: resistência de flexão, 161,4 ± 17,2 kgf rigidez, 64,5 ± 1,8 kgf/mm, ductilidade, > 25,4 mm. Grupo II: resistência de flexão, 124,7 ± 4,4, rigidez 59,6 ± 2,3, ductilidade > 25,4 mm. Para análise estatística foi adotado o teste de Mann-Whitney e a determinação de significância foi de 5% (pOBJECTIVE: To evaluate, both individually and comparatively, dynamic hip system-type plates marketed by two local manufacturers, to statistically analyze its results and show the lack of parameters for its manufacturing. METHODS: Static tests of flexion were carried out in five DHS plates of the manufacturer I (I group I) and in equal quantity of the same model of the manufacturer II (I group II), being all made in stainless austenitic ASTM F 138 steel, with four holes and a 135º angle. A servo-hydraulic MTS machine, Test Star II model, was used with a load capacity of 10 tons and dislocation control. The data were obtained from the applied load (P) as a function of the vertical dislocation of the piston (L), whose speed was 5mm/min. The tests were shutdown after reaching the maximum vertical flexion specified by the tests' standards. RESULTS: GroupI: flexion resistance, 161,4 ± 17,2 kgf rigidity, 64,5 ± 1,8 kgf/mm, flexibility, > 25,4 mm. Group II: flexion resistance, 124,7 ± 4,4,rigidity 59,6 ± 2,3, flexibility > 25,4 mm. For statistical analysis, the Mann-Whitney test was adopted and the determination of significance was 5 % (p

Abstract Objective To evaluate, through biomechanical testing, the resistance to and energy required for the occurrence of proximal femoral fracture in synthetic bone after removal of a proximal femoral nail model (PFN), comparing the results obtained with a reinforcement technique using polymethylmethacrylate (PMMA). Methods Fifteen synthetic bones were used: five units for the control group (CG), five for the test group without reinforcement (TGNR), and five for the test group with reinforcement (TGR). The biomechanical analysis was performed simulating a fall on the trochanter using a servo-hydraulic machine. In the GC, the assay was performed with the PFN intact. In the TGNR and TGR groups, a model of PFN was introduced and the tests were performed in the TGNR, after simple removal of the synthesis material, and in the TGR, after removal of the same PFN model and filling of the cavity in the femoral neck with PMMA. Results All groups presented a basicervical fracture. The CG presented a mean of 1427.39 Newtons (N) of maximum load and 10.14 Joules (J) of energy for the occurrence of the fracture. The TGNR and TGR presented 892.14 N and 1477.80 N of maximum load, and 6.71 J and 11.99 J of energy, respectively. According to the Kruskal-Wallis ANOVA, there was a significant difference in the maximum load (p = 0.009) and energy (p = 0.007) between these groups. Conclusion The simple removal of a PFN in synthetic bone showed a significant reduction of the maximum load and energy for the occurrence of fracture, which were re-established with a reinforcement technique using PMMA.

Abstract The authors report a single case of complex primary hip total arthroplasty in a 34-yearold female patient with a 5.5 cm lower limb dysmetria, in whom a maximum gluteus tenotomy was performed in order to prevent sciatic nerve injury. The surgery was performed under electroneurophysiological monitoring of the fibular and tibial branches of the sciatic nerve, collecting pretenotomy, posttenotomy, and postarthroplasty reduction data. The findings demonstrate that the maximum gluteus tenotomy improved the motor response of the fibular component of the sciatic nerve.

Abstract Objective This study aims to evaluate, through biomechanical tests, the resistance and energy required for proximal femoral fracture in synthetic bones after removing cannulated screws shaped as an inverted triangle, comparing the obtained results to those of a reinforcement technique with polymethylmethacrylate (PMMA) as bone cement. Methods Twenty synthetic bones were used: 10 units for the control group (CG), 5 units for the test group without reinforcement (TGW/O), and 5 units for the test group using a reinforcement technique with PMMA (TGW). The biomechanical analysis simulated a fall on the large trochanter using a servo-hydraulic machine. Results All TGW/O and CG specimens had a basicervical fracture. Three TGW specimens presented a basicervical fracture, and two suffered a fracture near the fixation point of the device (femoral diaphyseal region), with one of thembeing associated with a femoral neck fracture. A mean PMMA volume of 8.2 mL was used to fill the 3 screw holes in the TGWgroup. According to the one-way analysis of variance (ANOVA) and the Tukey multiple comparisons tests at a 5% level, the TGW presented a statistically significant difference when compared with the other groups in all parameters: maximal load (p = 0.001) and energy until fracture (p = 0.0001). Conclusion The simple removal of the cannulated screws did not reduce significantly the maximum load and energy for fracture occurrence, but the proximal femoral reinforcement with PMMA significantly increased these parameters, modifying the fracture pattern.

Abstract Objective To measure the cost of simultaneous total knee arthroplasty, as well as the costs of total and intensive care unit (ICU) length of stay, perioperative complications and need for blood transfusion compared to the costs of unilateral procedure in a referral hospital, in Federal District, Brazil. Method The present article is a retrospective study analyzing the medical records of patients admitted for unilateral or bilateral total knee arthroplasty, performed between June 2011 and March 2017. Seventy-four medical records were included in the study for evaluation of data such as total cost of the procedure, comorbidities, complications, days of hospitalization, and need for blood transfusion. Results A significantly higher incidence of deep vein thrombosis (DVT) was found in unilateral procedures. Compared to the other data, no statistically significant differences were found in the relative costs or in the need for blood transfusion. Conclusion There was no increase in the cost or in complications when comparing the simultaneous bilateral knee joint replacement procedure with the unilateral procedure, which corroborates most of the literature.