Finite element analysis of the stability of Mason type Ⅲ radial head fracture fixed with three cross-bridge headless compression screw and locking plate / 中国骨伤

OBJECTIVE@#To compare the biomechanical stability of three cross-bridge headless compression screws and locking plates in the fixation of Mason type Ⅲ radial head fractures by finite element method.@*METHODS@#Using reverse modeling technology, the radial CT data and internal fixation data of a healthy 25-year-old male were imported into the relevant software. Three-dimensional finite element model of 3 cross-bridge headless compression screws and locking plates for MasonⅢ radial head fractures were established, and the radial head was loaded with 100 N axial loading. The maximum displacement, maximum Von Mises stress and stress distribution of the two groups were compared.@*RESULTS@#The maximum displacements of the three cross-bridge screws group and locking plate group were 0.069 mm and 0.087 mm respectively, and the Von Mises stress peaks were 18.59 MPa and 31.85 MPa respectively. The stress distribution of the three screws group was more uniform.@*CONCLUSION@#Both internal fixation methods can provide good fixation effect. CoMPared with the locking plate fixation method, the 3 cross-bridge headless compression screws fixation is more stable and the stress distribution is more uniform.

Single Kocher-Langenbeck approach combined with anterograde channel screw technique in treatment of acetabular transverse and posterior wall fractures / 中国修复重建外科杂志

OBJECTIVE@#To assess the effectiveness of the single Kocher-Langenbeck approach combined with anterograde channel screw technique for the treatment of acetabular transverse and posterior wall fractures.@*METHODS@#Between March 2020 and October 2022, 17 cases of acetabular transverse and posterior wall fractures were treated with the single Kocher-Langenbeck approach combined with anterograde channel screw technique. There were 11 males and 6 females, with an average age of 53.6 years (range, 42-64 years). Causes of injury included traffic accident in 12 cases, and falling from height in 5 cases. The time from injury to operation ranged from 4 to 16 days with an average of 8.8 days. The operation time, intraoperative blood loss, and fluoroscopy frequency were recorded; X-ray films were reviewed regularly after operation to observe the fracture healing, and postoperative complications were recorded. At last follow-up, Matta score was used to evaluate the reduction of fracture, Harris score and modified Merle D'Aubigné-Postel scores system were used to evaluate the hip joint function.@*RESULTS@#The operation time was 150-230 minutes (mean, 185.9 minutes), the intraoperative blood loss was 385-520 mL (mean, 446.2 mL), and the fluoroscopy frequency was 18-34 times (mean, 27.5 times). Postoperative fat liquefaction occurred in 1 case and the other incisions healed by first intention; 3 cases had limb numbness after operation, and the symptoms disappeared after active symptomatic treatment; no urogenital system and intestinal injury occurred. All patients were followed up 12-28 months (mean, 19.9 months). Bone union was achieved in all cases with an average healing time of 10.8 weeks (range, 8-14 weeks). There was no complication such as loosening and breakage of internal fixators. At last follow-up, according to Matta score, 12 cases achieved anatomic reduction, 3 satisfactory reduction, and 2 fair reduction, the satisfactory rate was 88.2%; according to Harris hip function score, 12 cases were excellent, 3 good, and 2 fair, the excellent and good rate was 88.2%; according to the modified Merle D'Aubign Aubigné-Postel scoring system, the results were excellent in 11 cases, good in 3 cases, and fair in 3 cases, with an excellent and good rate of 82.4%.@*CONCLUSION@#The single Kocher-Langenbeck approach combined with anterograde channel screw technique is a minimally invasive method for the treatment of acetabular transverse and posterior wall fractures with less complications, simple operation, and satisfactory effectiveness.

O-arm navigation versus C-arm navigation for guiding percutaneous long sacroiliac screws placement in treatment of Denis type Ⅱ sacral fractures / 中国修复重建外科杂志

OBJECTIVE@#To compare the effectiveness of O-arm navigation and C-arm navigation for guiding percutaneous long sacroiliac screws in treatment of Denis type Ⅱ sacral fractures.@*METHODS@#A retrospective study was conducted on clinical data of the 46 patients with Denis type Ⅱ sacral fractures between April 2021 and October 2022. Among them, 19 patients underwent O-arm navigation assisted percutaneous long sacroiliac screw fixation (O-arm navigation group), and 27 patients underwent C-arm navigation assisted percutaneous long sacroiliac screw fixation (C-arm navigation group). There was no significant difference in gender, age, causes of injuries, Tile classification of pelvic fractures, combined injury, the interval from injury to operation between the two groups ( P>0.05). The intraoperative preparation time, the placement time of each screw, the fluoroscopy time of each screw during placement, screw position accuracy, the quality of fracture reduction, and fracture healing time were recorded and compared, postoperative complications were observed. Pelvic function was evaluated by Majeed score at last follow-up.@*RESULTS@#All operations were completed successfully, and all incisions healed by first intention. Compared to the C-arm navigation group, the O-arm navigation group had shorter intraoperative preparation time, placement time of each screw, and fluoroscopy time, with significant differences ( P<0.05). There was no significant difference in screw position accuracy and the quality of fracture reduction ( P>0.05). There was no nerve or vascular injury during screw placed in the two groups. All patients in both groups were followed up, with the follow-up time of 6-21 months (mean, 12.0 months). Imaging re-examination showed that both groups achieved bony healing, and there was no significant difference in fracture healing time between the two groups ( P>0.05). During follow-up, there was no postoperative complications, such as screw loosening and breaking or loss of fracture reduction. At last follow-up, there was no significant difference in pelvic function between the two groups ( P>0.05).@*CONCLUSION@#Compared with the C-arm navigation, the O-arm navigation assisted percutaneous long sacroiliac screws for the treatment of Denis typeⅡsacral fractures can significantly shorten the intraoperative preparation time, screw placement time, and fluoroscopy time, improve the accuracy of screw placement, and obtain clearer navigation images.

Comparative Assessment of Contact Osteogenesis at the Titanium Implant-Bone Junction in Male Rabbits with Dissimilar Femoral Defects / Evaluación Comparativa de la Osteogénesis de Contacto en la Unión entre el Hueso y el Implante de Titanio en Conejos Macho con Defectos Femorales Diferentes

SUMMARY: Traumatized bone tissue has the capacity to repair itself so that it eventually regains its almost original form, even in the case of artificially inserted implants. The process that stays at the base of the regeneration is represented by osteogenesis or remote osteogenesis. The major difference between the two types of bone formation is the location of the cement line, which is located on the surface of the implant for contact osteogenesis and on the surface of the bone defect for remote osteogenesis. The aim of the present study was to assess the contact osteogenesis in the case of inserted titanium screws in holes with diameters of 1.8 mm and 1 mm respectively. The obtained results show, in the case of the groove with 1.8 mm that the newly proliferated bone represents 73.85 % of the total area, while in the case of the groove with 1 mm in diameter the value of the newly proliferated bone is 26.15 %. In conclusion, the insertion of titanium screws by self-tapping into the hole smaller than the core of the screw is accompanied by bone proliferation by contact osteogenesis much more modest than in the case of insertion into the hole larger than the core of the screw.

El tejido óseo traumatizado tiene la capacidad de reparar en forma espontánea, de modo que eventualmente recupera su forma casi original, incluso en el caso de implantes insertados artificialmente. El proceso que queda en la base de la regeneración está representado por la osteogénesis u osteogénesis a distancia. La principal diferencia entre los dos tipos de formación ósea es la ubicación de la línea de cemento, que se encuentra en la superficie del implante para la osteogénesis de contacto y en la superficie del defecto óseo para la osteogénesis remota. El objetivo del presente estudio fue evaluar la osteogénesis de contacto en el caso de tornillos de titanio insertados en forámenes con diámetros de 1,8 mm y 1 mm respectivamente. Los resultados obtenidos muestran, en el caso del surco de 1,8 mm que el hueso neoproliferado representa el 73,85 % del área total, mientras que en el caso del surco de 1 mm de diámetro el valor del hueso neoproliferado es del 26,15 %. En conclusión, la inserción de tornillos de titanio por autorroscantes en el foramen menor que el núcleo del tornillo se acompaña de una proliferación ósea por osteogénesis de contacto mucho más modesta que en el caso de la inserción en el foramen mayor que el núcleo del tornillo.

Analysis of the Mechanical Behavior of Porcine Graft Fixation in a Polyurethane Block Using a 3D-printed PLA Interference Screw / Análise do comportamento mecânico da fixação do enxerto suíno em um bloco de poliuretano usando um parafuso de interferência PLA impresso em 3D

Abstract Objective The interest in using 3D printing in the healthcare field has grown over the years, given its advantages and potential in the rapid manufacturing of personalized devices and implants with complex geometries. Thus, the aim of the present study was to compare the mechanical fixation behavior of a 3D-printed interference screw, produced by fused deposition modeling of polylactic acid (PLA) filament, with that of a titanium interference screw. Methods Eight deep flexor porcine tendons, approximately 8 mm wide and 9 cm long, were used as graft and fixed to a 40 pounds-per-cubic-foot (PCF) polyurethane block at each of its extremities. One group was fixed only with titanium interference screws (group 1) and the other only with 3D-printed PLA screws (BR 20 2021 018283-6 U2) (group 2). The tests were conducted using an EMIC DL 10000 electromechanical universal testing machine in axial traction mode. Results Group 1 (titanium) obtained peak force of 200 ± 7 N, with mean graft deformation of 8 ± 2 mm, and group 2 (PLA) obtained peak force of 300 ± 30 N, and mean graft deformation of 7 ± 3 mm. Both the titanium and PLA screws provided good graft fixation in the polyurethane block, with no slippage or apparent deformation. In all the samples, the test culminated in graft rupture, with around 20 mm of deformation in relation to the initial length. Conclusion The 3D-printed PLA screw provided good fixation, similar to that of its titanium counterpart, producing satisfactory and promising results.

Resumo Objetivo O interesse em utilizar a impressão 3D na área da saúde tem crescido ao longo dos anos, dadas as suas vantagens e o seu potencial na rápida fabricação de dispositivos e implantes personalizados com geometrias complexas. Assim, o objetivo do presente estudo foi comparar o comportamento de fixação mecânica de um parafuso de interferência impresso em 3D, produzido pela modelagem fundida de deposição do filamento de ácido polilático (PLA), com o de um parafuso de interferência de titânio. Métodos Oito tendões suínos flexores profundos, de aproximadamente 8 mm de largura e 9 cm de comprimento, foram utilizados como enxerto e fixados em um bloco de poliuretano de 40 PCF em cada uma de suas extremidades. Um grupo foi fixado apenas com parafusos de interferência de titânio (grupo 1) e o outro apenas com parafusos PLA impressos em 3D (BR 20 2021 018283-6 U2) (grupo 2). Os testes foram realizados utilizando uma máquina de teste universal eletromecânica EMIC DL 10.000 no modo de tração axial. Resultados O grupo 1 (titânio) obteve força máxima de 200 ± 7 N com deformação média do enxerto de 8 ± 2 mm, e a força máxima do grupo 2 (PLA) foi de 300 ± 30 N e deformação média do enxerto de 7 ± 3 mm. Ambos os parafusos de titânio e PLA forneceram boa fixação de enxerto no bloco de poliuretano, sem deslizamento ou deformação aparente. Em todas as amostras o teste culminou na ruptura do enxerto, com cerca de 20 mm de deformação em relação ao comprimento inicial. Conclusão O parafuso PLA impresso em 3D proporcionou boa fixação, semelhante à de sua contraparte de titânio, produzindo resultados satisfatórios e promissores.

Pipkin Type-II Femoral Head Fracture: A Biomechanical Evaluation by the Finite-Element Method / Fratura da cabeça femoral de tipo II de Pipkin: Avaliação biomecánica pelo método de elementos finitos

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.

Resumo Objetivo Avaliar a capacidade biomecánica de duas formas de fixação de fraturas tipo II de Pipkin descrevendo o desvio da fratura no sentido vertical, as tensões máxima e mínima principais, e a tensão equivalente de Von Mises nas sínteses utilizadas. Materiais e Métodos Dois fixadores internos foram desenvolvidos para tratar a fratura tipo II de Pipkin por meio de elementos finitos: parafuso cortical de 3,5 mm e parafuso de Herbert. Sob as mesmas condições, foram avaliados o desvio da fratura no sentido vertical, as tensões máxima e mínima principais, e a tensão equivalente de Von Mises nas sínteses utilizadas. Resultados Os deslocamentos verticais avaliados foram de 1,5 mm e 0,5 mm. Os valores de tensão máxima obtidos na região superior do colo femoral foram de 9,7 KPa e 1,3 KPa, e os valores de tensão mínima obtidos na região inferior do colo femoral foram de -8,7KPa e -9,3 KPa. Por fim, os valores de pico da tensão equivalente de Von Misesforam de 7,2 GPa e2,0 GPa paraosmodelos de fixação com o uso do parafuso cortical de 3,5 mm e do parafuso de Herbert, respectivamente. Conclusão Osistema de fixação com parafuso de Herbert gerou os melhores resultados em termos de redução do deslocamento vertical, distribuição da tensão máxima e do pico da tensão equivalente de Von Mises, o que demonstra sua superioridade mecânica comparada à do parafuso cortical de 3,5 mm no tratamento da fratura tipo II de Pipkin.

Is there a Difference in Interfragmentary Compression Strength Between Fully or Partially Threaded Screws? Results of an Experimental Biomechanical Pilot Study / Há diferença na força de compressão interfragmentar entre parafusos com rosca total ou parcial? Resultados de um estudo biomecânico experimental piloto

Abstract Objective This study assessed differences between fully- and partially-threaded screws in the initial interfragmentary compression strength. Our hypothesis was that there would be an increased loss in initial compression strength with the partially-threaded screw. Methods A 45-degree oblique fracture line was created in artificial bone samples. The first group (FULL, n = 6) was fixed using a 3.5-mm fully-threaded lag screw, while the second group (PARTIAL, n = 6) used a 3.5-mm partially-threaded lag screw. Torsional stiffness for both rotational directions were evaluated. The groups were compared based on biomechanical parameters: angle-moment-stiffness, time-moment-stiffness, maximal torsional moment (failure load), and calibrated compression force based on pressure sensor measurement. Results After loss of one PARTIAL sample, no statistically significant differences in calibrated compression force measurement were observed between both groups: [median (interquartile range)] FULL: 112.6 (10.5) N versus PARTIAL: 106.9 (7.1) N, Mann-Whitney U-test: p = 0.8). In addition, after exclusion of 3 samples for mechanical testing (FULL n = 5, PARTIAL n = 4), no statistically significant differences were observed between FULL and PARTIAL constructs in angle-moment-stiffness, time-moment-stiffness, nor maximum torsional moment (failure load). Conclusion There is no apparent difference in the initial compression strength (compression force or construct stiffness or failure load) achieved using either fully-or partially-threaded screws in this biomechanical model in high-density artificial bone. Fully-threaded screws could, therefore, be more useful in diaphyseal fracture treatment. Further research on the impact in softer osteoporotic, or metaphyseal bone models, and to evaluate the clinical significance is required.

Resumo Objetivo Este estudo avaliou diferenças entre parafusos com rosca total ou parcial na resistência à compressão interfragmentar inicial. Nossa hipótese era de que haveria maior perda de resistência à compressão inicial com o parafuso de rosca parcial. Métodos Uma linha de fratura oblíqua de 45 graus foi criada em amostras de osso artificial. O primeiro grupo (TOTAL, n = 6) foi fixado com um parafuso de 3,5 mm de rosca total, enquanto o segundo grupo (PARCIAL, n = 6) usou um parafuso de 3,5 mm de rosca parcial. Avaliamos a rigidez à torção em ambas as direções de rotação. Os grupos foram comparados com base nos seguintes parâmetros biomecânicos: momento de rigidez-ângulo, momento de rigidez-tempo, momento de torção máxima (carga de falha) e força de compressão calibrada com base na medida do sensor de pressão. Resultados Depois da perda de uma amostra PARCIAL, não foram observadas diferenças estatisticamente significativas na força de compressão calibrada entre os 2 grupos [mediana (intervalo interquartil)]: TOTAL: 112,6 (10,5) N e PARCIAL: 106,9 (7,1) N, com p = 0,8 segundo o teste U de Mann-Whitney). Além disso, após a exclusão de 3 amostras para testes mecânicos (TOTAL, n = 5, PARCIAL, n = 4), não foram observadas diferenças estatisticamente significativas entre os construtos TOTAL e PARCIAL quanto ao momento de rigidez-ângulo, momento de rigidez-tempo ou momento de torção máxima (carga de falha). Conclusão Não há diferença aparente na força de compressão inicial (força de compressão ou rigidez do construto ou carga de falha) com o uso de parafusos de rosca total ou parcial neste modelo biomecânico em osso artificial de alta densidade. Parafusos de rosca total podem, portanto, ser mais úteis no tratamento de fraturas diafisárias. Mais pesquisas são necessárias sobre o impacto em modelos ósseos osteoporóticos ou metafisários de menor densidade e avaliação do significado clínico.

Posterior Atlantoaxial Screw Placement in a Portuguese Population: A Morphometric Analysis Based on Computed Tomography Scan Measurements / Colocação de parafusos atlantoaxiais posteriores em uma população portuguesa: Uma análise morfométrica baseada em medidas de tomografia computadorizada

Abstract Objective The present study aims to evaluate the screw length and trajectory angles for posterior atlantoaxial fixation in a Portuguese population, through the study of cervical computed tomography (CT) scans. Methods Cervical CT scans of 50 adults were measured according to predefined screw trajectories of C1-C2 transarticular (C1C2TA), C1 lateral mass (C1LM), C2 pedicle (C2P), C2 pars and C2 laminar (C2L) screws. For each of these trajectories, screw length and angles were measured and compared between males and females. Results For the C1C2TA screw trajectory, the mean length, medial, and cranial angles were 34.12 ± 3.19 mm, 6.24° ± 3.06, and 59.25° ± 5.68, respectively, and for the C1LM screw trajectory, they were 27.12 ± 2.15 mm, 15.82° ± 5.07, and 13.53° ± 4.80, respectively. The mean length, medial, and cranial angles for the C2P screw trajectory were 23.44 ± 2.49 mm, 27.40° ± 4.88, and 30.41° ± 7.27, respectively; and for the C2 pars screw trajectory, they were 16.84 ± 2.08 mm, 20.09° ± 6.83, and 47.53° ± 6,97. The mean length, lateral, and cranial angles for the C2L screw trajectory were 29.10 ± 2.48 mm, 49.80° ± 4.71, and 21.56° ± 7.76, respectively. There were no gender differences except for the lengths of the C1C2TA (p= 0,020) and C2L (p= 0,001) screws, which were greater in males than in females. Conclusion The present study provides anatomical references for the posterior atlantoaxial fixation in a Portuguese population. These detailed data are essential to aid spine surgeons to achieve safe and effective screw placement.

Resumo Objetivo O presente estudo tem como objetivo avaliar o comprimento e os ângulos de trajetória do parafuso para fixação atlantoaxial posterior em uma população portuguesa por meio do estudo de tomografia computadorizada (TC) cervical. Métodos Tomografias computadorizadas cervicais de 50 adultos foram analisadas quanto às trajetórias pré-definidas dos parafusos transarticulares C1-C2 (C1C2TA), na massa lateral de C1 (C1LM), no pedículo de C2 (C2P) e na pars de C2 e C2 laminar (C2L). O comprimento e os ângulos dos parafusos em cada uma destas trajetórias foram medidos e comparados entre homens e mulheres. Resultados O comprimento médio e ângulos medial e cranial da trajetória do parafuso C1C2TA foram de 34,12 ± 3,19 mm, 6,24° ± 3,06 e 59,25° ± 5,68, respectivamente; as medidas da trajetória do parafuso C1LM foram 27,12 ± 2,15 mm, 15,82° ± 5,07 e 13,53° ± 4,80. O comprimento médio e os ângulos medial e cranial da trajetória do parafuso C2P foram de 23,44 ± 2,49 mm, 27,40° ± 4,88 e 30,41° ± 7,27, respectivamente; as medidas da trajetória do parafuso da pars de C2 foram 16,84 ± 2,08 mm, 20,09° ± 6,83 e 47,53° ± 6,97. O comprimento médio e ângulos lateral e cranial da trajetória do parafuso C2L foram de 29,10 ± 2,48 mm, 49,80° ± 4,71 e 21,56° ± 7,76, respectivamente. Não houve diferenças entre os gêneros, à exceção do comprimento dos parafusos C1C2TA (p= 0,020) e C2L (p= 0,001), que foi maior no sexo masculino do que no feminino. Conclusão O presente estudo fornece referências anatômicas para a fixação atlantoaxial posterior em uma população portuguesa. Estes dados detalhados são essenciais para ajudar os cirurgiões de coluna a colocar os parafusos de maneira segura e eficaz.

Comparison between Fixation with Smooth Kirschner Wire and Cannulated Screws in Displaced Fractures of the Lateral Humeral Condyle in Children / Comparação entre fixação de fio de Kirschner liso e de parafusos canulados em fraturas deslocadas do côndilo lateral do úmero em crianças

Abstract Objective To compare the use of cannulated screws and smooth Kirschner wires in terms of reducing the presence of exuberant callus and complications in pediatric displaced fractures of the lateral humeral condyle. Methods An analytical cross-sectional study of consecutive cases was conducted from May to October 2021 with 30 children with displaced external humeral condyle fractures. The functional results regarding pain and range of motion were stratified using the Dhillon grading system. Results A total of 19 patients underwent Kirschner wire fixation, and 11 underwent cannulated screw fixation. Closed fixation was performed in 14 cases (47%), and open fixation, in 16 (53%). Of the cases included, there was no loss to follow-up. Te sample was composed of 21 (70%) male patients, and the age ranged from 5 to 15 years, with a mean of 6.96 years. The most frequent cause of fracture was fall from height (50%), which was related to greater displacement on baseline radiographs. Complications that were not related to the reduction approach or the implant used were observed in 12 (40%) cases. Conclusion The present study shows no benefits in relation to the use of smooth pins or cannulated screws to reduce the presence of exuberant callus in the consolidation of the fracture. We see that the complications that arise are related to the severity of the injury, and benefits cannot be identified in the choice of one implant over another. We could see that the Weiss classification helps to define the behavior in favor of open or closed reduction without interfering in kindness of the smooth pin or the cannulated screw for fracture fixation.

Resumo Objetivo Comparar o uso de parafusos canulados e de fios de Kirschner lisos em termos da redução da presença de calo exuberante e de complicações em fraturas pediátricas deslocadas do côndilo lateral do úmero. Métodos Um estudo analítico transversal de casos consecutivos foi realizado de maio a outubro de 2021 com 30 crianças com fraturas deslocadas de côndilo umeral externo. Os resultados funcionais para dor e amplitude de movimento foram estratificados utilizando o sistema de classificação Dhillon. Resultados Ao todo, 19 pacientes foram submetidos à fixação de fio Kirschner, e 11 à fixação de parafusos canulados. A fixação realizada foi fechada em 14 casos (47%) e aberta em 16 (53%). Dos casos incluídos, não houve perda no acompanhamento. A amostra continha 21 (70%) pacientes do sexo masculino, e a idade variou de 5 a 15 anos, com média de 6,96 anos. A causa mais frequente de fratura foi queda de altura (50%), e esteve relacionada ao maior deslocamento nas radiografias da linha de base. Complicações que não estavam relacionadas à abordagem de redução ou ao implante utilizado foram observadas em 12 (40%) casos. Conclusão Este estudo não mostra benefícios em relação ao uso de pinos lisos ou de parafusos canulados para reduzir a presença de calo exuberante na consolidação da fratura. Vemos que as complicações que surgem estão relacionadas à gravidade da lesão, e não é possível identificar benefícios na escolha de um implante ou outro. Pudemos ver que a classificação de Weiss ajuda a definir o comportamento em favor da redução aberta ou fechada sem dar preferência ao pino liso ou ao parafuso canulado para a fixação da fratura.

Evaluation of Screws Positioning in Latarjet Surgery: Is There a Correlation between Parallelism to Glenoid and Radiographic Complications? / Avaliação do posicionamento dos parafusos na cirurgia de Latarjet: Existe correlação entre paralelismo à glenoide e complicações radiográficas?

Abstract Objective To evaluate whether the parallelism of screws with glenoid in Latarjet surgery interferes in the positioning of the graft and to verify the reproducibility of a method of measuring screws positioning. Methods Retrospective, multicenter study, of patients with anterior shoulder instability submitted to modified Latarjet surgery and at least one year of postoperative follow-up. Two radiologists analyzed the postoperative tomographic images, acquired in a database, to evaluate the positioning of screws and radiographic complications. Results We evaluated 34 patients, aged between 21 and 60 years, one of them with bilateral shoulder involvement, totaling 35 shoulders evaluated. The tomographic evaluation of the inclination angles of the screws showed no difference between the observers. There was intra- and interobserver agreement to evaluate the following surgical parameters: graft position, presence or not of radiographic complications. Conclusion The technique described for measuring the parallelism of screws in Latarjet surgery presented a very good and excellent intra-observer agreement, respectively. Screw parallelism with glenoid is recommended; however, it is not a mandatory and unique condition to avoid radiographic complications.

Resumo Objetivo Avaliar se o paralelismo dos parafusos com a glenoide na cirurgia de Latarjet interfere no posicionamento do enxerto e verificar a reprodutibilidade de um método de mensuração da posição dos parafusos. Métodos Estudo retrospectivo, multicêntrico, de pacientes com instabilidade anterior do ombro submetidos à cirurgia de Latarjet modificada e no mínimo 1 ano de seguimento pós-operatório. Dois médicos radiologistas analisaram as imagens tomográficas pós-operatórias, adquiridas em um banco de dados, para avaliação do posicionamento dos parafusos e das complicações radiográficas. Resultados Foram avaliados 34 pacientes, com idades entre 21 e 60 anos, sendo que um deles tinha acometimento bilateral dos ombros, totalizando 35 ombros avaliados. A avaliação tomográfica dos ângulos de inclinação dos parafusos não apresentou diferença entre os observadores. Houve concordância intra e interobservador para avaliação dos seguintes parâmetros cirúrgicos: posição do enxerto, presença ou não de complicações radiográficas. Conclusão A técnica descrita para mensuração do paralelismo dos parafusos na cirurgia de Latarjet apresentou uma concordância intra e inter observador muito boa e excelente, respectivamente. O paralelismo do parafuso com a glenoide é recomendado; no entanto, não é condição obrigatória e única para se evitar as complicações radiográficas.

Feasibility analysis and nail planning ofS2 iliac crest screw placement in children / 中国骨伤

OBJECTIVE@#To evaluate the feasibility of S2 alar iliac screw insertion in Chinese children using computerized three-dimension reconstruction and simulated screw placement technique, and to optimize the measurement of screw parameters.@*METHODS@#A total of 83 pelvic CT data of children who underwent pelvic CT scan December 2018 to December 2020 were retrospectively analyzed, excluding fractures, deformities, and tumors. There were 44 boys and 39 girls, with an average age of (10.66±3.52) years, and were divided into 4 groups based on age (group A:5 to 7 years old;group B:8 to 10 years old;group C:11-13 years old;group D:14 to 16 years old). The original CT data obtained were imported into Mimics software, and the bony structure of the pelvis was reconstructed, and the maximum and minimum cranial angles of the screws were simulated in the three-dimensional view with the placement of 6.5 mm diameter S2 alar iliac screws. Subsequently, the coronal angle, sagittal angle, transverse angle, total length of the screw, length of the screw in the sacrum, width of the iliac, and distance of the entry point from the skin were measured in 3-Matic software at the maximum and minimum head tilt angles, respectively. The differences among the screw parameters of S2 alar iliac screws in children of different ages and the differences between gender and side were compared and analyzed.@*RESULTS@#In all 83 children, 6.5 mm diameter S2 iliac screws could be placed. There was no significant difference between the side of each screw placement parameter. The 5 to 7 years old children had a significantly smaller screw coronal angle than other age groups, but in the screw sagittal angle, the difference was more mixed. The 5 to 7 years old children could obtain a larger angle at the maximum head tilt angle of the screw, but at the minimum cranial angle, the larger angle was obtained in the age group of 11 to 13 years old. There were no significant differences among the age groups. The coronal angle and sagittal angle under maximum cephalic angle and minimum cranial angle of 5 to 7 years old male were (40.91±2.91)° and (51.85±3.75)° respectively, which were significantly greater than in female. The coronal angle under minimum cranial angle was significantly greater in girls aged 8-10 years old than in boys. For the remaining screw placement angle parameters, there were no significant differences between gender. The differences in the minimum iliac width, the screw length, and the length of the sacral screws showed an increasing trend with age in all age groups. The distance from the screw entry point to the skin in boys were significantly smaller than that of girls. The minimum width of the iliac in boys at 14 to 16 years of age were significantly wider than that in girls at the same stage. In contrast, in girls aged 5 to 7 years and 11 to 13 years, the screw length was significantly longer than that of boys at the same stage.@*CONCLUSION@#The pelvis of children aged 5 to 16 years can safely accommodate the placement of 6.5 mm diameter S2 alar iliac screws, but the bony structures of the pelvis are developing and growing in children, precise assessment is needed to plan a reasonable screw trajectory and select the appropriate screw length.

Effect of lag screw and support plate through axillary approach for the treatment of Ideberg typeⅡscapular pelvis fracture / 中国骨伤

OBJECTIVE@#To analyze the effect of lag screw and support plate through axillary approach for the treatment of Ideberg typeⅡscapular pelvis fracture.@*METHODS@#From January 2016 to June 2021, 26 patients with Ideberg typeⅡglenoid fractures were treated with trans-axillary lag screw combined with supporting plate, including 15 males and 11 females. The age ranged from 21 to 75 years, with an average of (43.12±6.56) years old. The Constant-Murley Shoulder joint Scale and University of California at Los Angeles (UCLA) score were used to evaluate the function and clinical efficacy of shoulder joint.@*RESULTS@#All patients were followed up, and the duration ranged from 19 to 42 months, with an average of (30.6±10.5) months. One year after surgery, the Constant-Murley score increased from preoperative 34.9±2.5(ranged, from 28 to 47) to 87.2±6.8(ranged, from 70 to 95). The UCLA score improved from preoperative 17.9±1.7(9 to 25) to 33.1±2.3(29 to 35). Seventeen patients got an excellent result, with 7 good, and 2 fair. None of the patients had infection, screw, and plate loosening, fracture, and other complications after surgery. Two patients had different degrees of Chronic pain in the shoulder during the follow-up period.@*CONCLUSION@#The treatment of Ideberg typeⅡscapular glenoid fractures through axillary approach with lag screws and supporting steel plates has the advantages of convenient exposure, direct visual restoration of the normal anatomical shape of the scapular glenoid, selection of suitable positions for screw and steel plate placement, achieving better treatment results, and fewer complications. It is an effective and reliable surgical method.

Modified application of interface screw in femoral side during anterior cruciate ligament reconstruction / 中国骨伤

OBJECTIVE@#To compare clinical effects of the improved interface screw fixation of femoral end of anterior cruciate ligament with classic femoral lateral loop plate fixation.@*METHODS@#A retrospective analysis of 65 patients who underwent arthroscopic anterior cruciate ligament reconstruction from January 2019 to September 2021 were performed. According to the different fixation methods of the femoral side, 35 patients were divided into loop plate fixation(loop plate group), including 27 males and 8 females, aged from 18 to 50 years old with an average of (35.00±7.60) years old;30 patients in interface screw fixation(interface screw group), including 20 males and 10 females, aged from 18 to 50 years old with an average of (32.00±8.50) years old. Hospital stay, hospital expenses, operation time, complications, C-reactive protein at 1, 3, 6 days after operation, and postoperative Lysholm score and International Knee Documentation Committee(IKDC) score at 18 months were compared between two groups.@*RESULTS@#All patients were successfully operated, and obtained follow-up from 18 to 36 months with an average of (25.16±4.50) months. Anterior drawer test and Lachman test of all patients turned to negative. There were no statistical differences in hospital stay, hospital expenses and complications between two groups(P>0.05);operation time in loop plate group was (74.00±6.84) min, and (91.67±6.34) min in interface screw group, and had difference between two groups(P<0.05). C-reactive protein on the 1st and 3rd day after operation was (40.00±10.10), (20.00±8.23) mg·L-1 in loop plate group, and (60.00±8.93), (30.00±8.66) mg·L-1 in interface nail group, had statistical difference between two groups (P<0.05);while there was no difference in C-reactive protein on the 6th day after operation(P>0.05). At 18 months after operation, Lysholm and IKDC scores showed no significant difference between two groups (P>0.05). In loop plate group, medullary enlargement on coronal and sagittal views were (2.75±0.19) mm, (1.55±0.25) mm, and (2.81±0.22) mm, (1.61±0.20) mm in interface screw group, and had statistical difference between two groups(P<0.05).@*CONCLUSION@#In the reconstruction of anterior cruciate ligament, the common interface screw on the femoral side is changed to the sheath interface screw, and intramedullary screw is changed to the compression and fixation of tendon from outside to inside of joint. Although the operation procedure is relatively complicated and operation time is slightly longer, it has advantages of no residual metal foreign body after operation, and clinical effect is no different from classical loop plate suspension fixation, which is still a good choice.

Clinical study on the subchondral screw compression technique assisted reduction of residual or secondary collapse of lateral tibial plateau / 中国修复重建外科杂志

OBJECTIVE@#To explore the reduction and support effect of the subchondral screw compression technique for residual or secondary collapse of the lateral tibial plateau during operation.@*METHODS@#Between January 2020 and June 2021, 11 patients with residual or secondary collapse of the lateral tibial plateau during operation were treated with the subchondral screw compression technique. There were 6 males and 5 females, aged 52.3 years old (range, 27-64 years). The fractures were caused by traffic accident in 10 cases and falling from height in 1 case and located at the left knee in 6 cases and the right knee in 5 cases. According to Schatzker classification, there were 5 cases of type Ⅱ fractures, 4 cases of type Ⅲ fractures, and 2 cases of type Ⅴfractures. According to the three columns classification, there were 5 cases of lateral column, 4 cases of lateral column and posterior column, and 2 cases of three columns. The time from injury to operation was 4.5 days (range, 3-7 days). During the follow-up, X-ray films were obtained and the Rasmussen standard was used to evaluate the quality of fracture reduction, meanwhile fracture healing was observed. The medial proximal tibial angle (mPTA), posterior tibial slope angle (pTSA), and articular surface collapse were measured at immediate and 12 months after operation. The knee joint range of motion was evaluated at last follow-up, and the knee joint function was evaluated using the Hospital for Special Surgery (HSS) score.@*RESULTS@#All operations were successfully completed, with a mean operation time of 71.4 minutes (range, 55-120 minutes), and a mean hospital stay of 8.0 days (range, 5-13 days). The incisions all healed by first intention, without complications such as infection, flap necrosis, or vascular and nerve injury. All patients were followed up 16.5 months on average (range, 12-24 months). X-ray films showed that the fracture reduction score was 14-18 (mean, 16.7) according to Rasmussen score criteria; and 5 cases were rated as excellent and 6 as good. All fractures healed clinically with a mean clinical healing time of 14.9 weeks (range, 12-16 weeks), and there was no complications such as plate or screw loosening. At 12 months after operation, the mPTA and pTSA were (87.5±1.7)° and (6.2±3.1)°, respectively; there was no significant difference when compared to the values at immediate after operation [(87.6±1.8)° and (6.5±3.1)°] ( P>0.05). The articular surface of the tibial plateaus was effectively supported, and it collapsed again by 0-1.0 mm at 12 months, with an average of 0.4 mm. At last follow-up, the knee joint range of motion was 115°-135° (mean, 126.8°) and the HSS score for knee joint function was 87-98 (mean, 93.9). Five patients underwent secondary operation to remove the internal fixator at 12-18 months after operation.@*CONCLUSION@#The subchondral screw compression technique is helpful for the reduction of residual or secondary collapse of the lateral tibial plateau during operation, and can provide good support for osteochondral blocks.

Arthroscopic treatment of scaphoid fracture nonunion with bone graft and Kirschner wire combined with screw fixation / 中国修复重建外科杂志

OBJECTIVE@#To explore the effectiveness of arthroscopic treatment of scaphoid fracture nonunion with bone graft and Kirschner wire combined with screw fixation.@*METHODS@#The clinical data of 14 patients with scaphoid fracture nonunion who met the selection criteria between February 2021 and September 2022 were retrospectively analyzed. There were 13 males and 1 female with an average age of 32 years ranging from 17 to 54 years. The time from injury to operation ranged from 6 to 15 months, with an average of 9.6 months. According to the Slade-Geissler classification of scaphoid fracture nonunion, there were 3 cases of grade Ⅲ, 8 cases of grade Ⅳ, and 3 cases of grade Ⅴ. The preoperative visual analogue scale (VAS) score was 5.9±1.0, and the modified Mayo wrist score was 53.2±9.1. There were 2 cases of scaphoid nonunion advanced collapse, both of which were stage Ⅰ. All patients were treated with arthroscopic bone graft and Kirschner wire combined with screw fixation, and the fracture healing was observed by X-ray film monthly after operation, and the effectiveness was evaluated by VAS score and modified Mayo wrist score before and after operation.@*RESULTS@#All patients were followed up 6-14 months, with an average of 8.4 months. All fractures healed in 4-8 months, with an average of 6.3 months. The postoperative pain symptoms and wrist function of the patients significantly improved when compared with those before operation, and the VAS score at last follow-up was 2.4±1.3, and the modified Mayo wrist score was 87.1±6.7, which were significantly different from those before operation ( t=12.851, P<0.001; t=-14.410, P<0.001). According to the modified Mayo wrist evaluation, 9 cases were excellent, 3 cases were good, and 2 cases were fair.@*CONCLUSION@#Arthroscopic bone graft and Kirschner wire combined with screw fixation is an effective surgical method for the treatment of scaphoid fracture nonunion.

Treatment of Ideberg type Ⅱ scapular glenoid fracture with compression screw combined with Buttress plate through direct axillary approach / 中国修复重建外科杂志

OBJECTIVE@#To investigate the effectiveness of compression screw combined with Buttress plate through direct axillary approach for Ideberg typeⅡ scapular glenoid fractures.@*METHODS@#A retrospective analysis was conducted on 11 patients with Ideberg type Ⅱ scapular glenoid fractures treated with compression screws combined with Buttress plate fixation through the direct axillary approach between January 2014 and June 2022. There were 7 males and 4 females, aged from 34 to 75 years, with an average of 56.0 years. The causes of injury included 4 cases of falling from height injury, 4 cases of heavy object injury, and 3 cases of traffic accident injury. The time from injury to operation was 2-5 days, with an average of 3.8 days. The operation time, intraoperative blood loss, hospital stay, complications, and fracture healing time were recorded. The Constant-Murley score, American Society of Shoulder and Elbow Surgeons (ASES) score, and shoulder joint flexion, abduction, external rotation (neutral position), and internal rotation (neutral position) range of motion were used to evaluate shoulder joint pain and function.@*RESULTS@#The operation time was 45-105 minutes, with an average of 79.0 minutes; the intraoperative blood loss was 80-200 mL, with an average of 99.2 mL; the hospital stay was 3-8 days, with an average of 5.8 days. One patient had poor wound healing after operation, and the wound healed after strengthening dressing change; the rest wounds had primary healing, and no axillary nerve paralysis occurred. Except for 1 patient lost follow-up, the remaining 10 patients were followed up 10-54 months, with an average of 26.4 months. The postoperative X-ray film examination showed that the fractures healed well within 8-15 weeks, with an average of 11.0 weeks. There was no complication such as fracture displacement, internal fixator failure or fracture during follow-up. At last follow-up, the patient's shoulder joint flexion, abduction, external rotation (neutral position), and internal rotation (neutral position) range of motion, Constant-Murley score, and ASES score significantly improved when compared with those before operation ( P<0.05).@*CONCLUSION@#Compression screw combined with Buttress plate through direct axillary approach is an effective way to treat Ideberg typeⅡ scapular glenoid fracture, with advantages of small trauma, concealed incision, and good effectiveness.

Effectiveness analysis of percutaneous parallel screw fixation via posterolateral "safe zone" for Hawkins type Ⅰ- Ⅲ talar neck fractures / 中国修复重建外科杂志

OBJECTIVE@#To explore the effectiveness of the percutaneous parallel screw fixation via the posterolateral "safe zone" for Hawkins type Ⅰ-Ⅲ talar neck fractures.@*METHODS@#A retrospective analysis was conducted on the clinical data from 35 patients who met the selection criteria of talar neck fractures between January 2019 and June 2021. According to the surgical method, they were divided into a study group (14 cases, using percutaneous posterolateral "safe zone" parallel screw fixation) and a control group (21 cases, using traditional open reduction and anterior cross screw internal fixation). There was no significant difference in gender, age, affected side, Hawkins classification, and time from injury to operation between the two groups ( P>0.05). The operation time, bone healing time, complications, and Hawkins sign were recorded, and the improvement of pain and ankle-foot function were evaluated by visual analogue scale (VAS) score and American Orthopaedic Foot and Ankle Society (AOFAS) ankle and hindfoot score at last follow-up. The overall quality of life was assessed by the short form of 12-item health survey (SF-12), which was divided into physical and psychological scores; and the satisfaction of patients was evaluated by the 5-point Likert scale.@*RESULTS@#The operation time in the study group was significantly shorter than that in the control group ( P<0.05). All patients werefollowed up 13-35 months, with an average of 20.6 months; there was no significant difference in the follow-up time between the two groups ( P>0.05). The time of bone healing in the study group was shorter than that in the control group, and the positive rate of Hawkins sign (83.33%) was higher than that in the control group (33.33%), and the differences were significant ( P<0.05). In the control group, there were 2 cases of incision delayed healing, 7 cases of avascular necrosis of bone, 3 cases of joint degeneration, 1 case of bone nonunion, and 3 cases of internal fixation irritation; while in the study group, there were only 2 cases of joint degeneration, and there was a significant difference in the incidence of complications between the two groups ( P<0.05). At last follow-up, there was no significant difference in VAS score between the two groups ( P>0.05), but the SF-12 physical and psychological scores, AOFAS ankle and hindfoot scores, and patients' satisfaction in the study group were significantly better than those in the control group ( P<0.05).@*CONCLUSION@#The treatment of Hawkins type Ⅰ-Ⅲ talar neck fractures with percutaneous parallel screw fixation via the posterolateral "safe zone" can achieve better effectiveness than traditional open surgery, with the advantages of less trauma, fewer complications, faster recovery, and higher patient satisfaction.

Research progress of tibial-graft fixation methods on anterior cruciate ligament reconstruction / 中国修复重建外科杂志

OBJECTIVE@#To review the studies about the tibial-graft fixation methods on anterior cruciate ligament (ACL) reconstruction, in order to provide clinical reference.@*METHODS@#The literature about the tibial-graft fixation methods on ACL reconstruction at home and abroad was extensively reviewed, and the factors that affect the selection of fixation methods were summarized.@*RESULTS@#The knee flexion angle, graft tension, and graft fixation device are mainly considered when the tibial-graft was fixed on ACL reconstruction. At present, the graft is mainly fixed at 0°/30° of knee flexion. The study shows that the knee joint is more stable after fixed at 30°, while the incidence of knee extension limitation decrease after fixed at 0°. In terms of graft tension, a good effectiveness can be obtained when the tension level is close to 90 N or the knee flexion is 30° to recover the affected knee over-restrained 2 mm relative to the healthy knee. In terms of the graft device, the interference screw is still the most commonly used method of tibial-graft fixation, with the development of all-inside ACL reconstruction in recent years, the cortical button fixation may become the mainstream.@*CONCLUSION@#Arthroscopic reconstruction is the main treatment of ACL rupture at present. However, there is no optimal fixation method for the tibial-graft, the advantages and disadvantages of each fixation methods need to be further studied.

Outcome of buttress plate-nail construct used for reconstruction of broken lateral wall in intertrochanteric fractures / 中华创伤杂志(英文版)

PURPOSE@#Intramedullary implants are well accepted fixation of all types of intertrochanteric (IT) fractures, both stable and unstable types. Intramedullary nails have an ability to effectively support the posteromedial part, but fail to buttress the broken lateral wall requiring lateral augmentation. The aim of this study was to evaluate the outcome of proximal femoral nail augmented with trochanteric buttress plate for broken lateral wall with IT fractures, which was fixed to the femur through hip screw and anti-rotation screw nail.@*METHODS@#Of 30 patients, 20 had Jensen-Evan type III and 10 had type V fractures. Patients with IT fracture of broken lateral wall and aged more than 18 years, in whom satisfactory reduction was achieved by closed methods, were included in the study. Patients with pathologic or open fractures, polytrauma, prior hip surgery, non-ambulatory prior to surgery, and those who refused to participate were excluded. The operative time, blood loss, radiation exposure, quality of reduction, functional outcome, and union time were evaluated. All data were coded and recorded in Microsoft Excel spread sheet program. SPSS 20.0 was used for data analysis and normality of the continuous data was checked using Kolmogorv Smirnov test.@*RESULTS@#The mean age of patients in the study was 60.3 years. The mean duration of surgery (min), mean intra-operative blood loss (mL) and mean number of exposures were 91.86 ± 12.8 (range 70 - 122), 144.8 ± 3.6 (range 116 - 208), and 56.6 (range 38 - 112), respectively. The mean union time was 11.6 weeks and the mean Harris hip score was 94.1.@*CONCLUSION@#Lateral trochanteric wall in IT fractures is significantly important, and needs to be reconstructed adequately. Nail-plate construct of trochanteric buttress plate fixed with hip screw and anti-rotation screw of proximal femoral nail can be successfully used to augment, fix or buttress the lateral trochanteric wall giving excellent to good results of early union and reduction.

Meta-analysis of the effect of hollow nail and bone plate on Lisfranc injury / 中国骨伤

OBJECTIVE@#To compare the clinical efficacy of screw and bone plate internal fixation in the treatment of Lisfranc injury.@*METHODS@#The databases of Wanfang, CNKI, Pubmed, EMBASE, VIP, BIOSIS and other databases were retrieved by computer, and the clinical trial literature from January 1, 2000 to August 1, 2021 was retrieved, the methodological quality of the included studies was strictly evaluated and the data were extracted, and the obtained data were meta-analyzed by Revman 5.4 software.@*RESULTS@#Nine randomized controlled trial literature and 10 retrospective cohort studies were included, of which 416 patients in the experimental group were treated with screw internal fixation, and 435 patients in the control group were treated with bone plate internal fixation. Meta-analysis showed that the surgical time of the bone plate internal fixation group was longer than that of the screw internal fixation group [MD=-14.40, 95%CI(-17.21, -11.60), P<0.000 01], the postoperative X-ray anatomical reduction of the bone plate internal fixation group [MD=0.47, 95%CI(0.25, 0.86), P=0.01], the excellent and good rate of postoperative American orthopedic foot and ankle society(AOFAS) foot function score[MD=0.25, 95%CI(0.15, 0.42), P<0.000 01], postoperative AOFAS foot function score [MD=-5.51, 95%CI(-10.10, -0.92), P=0.02] of the bone plate fixation group was better than those of the screw internal fixation group. Two kinds of operation method had no statistical different for postoperative fracture healing time[MD=1.91, 95%CI(-1.36, 5.18), P=0.25], postoperative visual analgue scale(VAS)[MD=0.38, 95%CI(0.09, 0.86), P=0.11], postoperative complications [MD=1.32, 95%CI(0.73, 2.40), P=0.36], the postoperative infection [MD=0.84, 95%CI(0.48, 1.46), P=0.53], the postoperative fracture internal fixation loosening [MD=1.25, 95% CI(0.61, 2.53), P=0.54], the postoperative incidence of traumatic arthritis [MD=1.80, 95%CI(0.83, 3.91), P=0.14].@*CONCLUSION@#Bone plate fixation has better short-term and medium-term results and lower reoperation rate in the treatment of Lisfranc injury, so it is recommended to use bone plate fixation in the treatment of Lisfranc injury.