Ensaio biomecânico após retirada de parafusos canulados do fêmur proximal (análise in vitro)

Freitas, Anderson; Ramos, Lucas Sacramento; Dantas, Érgon Lab; Neto, Vincenzo Giordano; Godinho, Patrick F; Shimano, Antonio Carlos

doi:10.1055/s-0039-1693046

Cited by 3 publications

(1 citation statement)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Some researchers conducted mechanical experiments to study the mechanical characteristics after removing hollow screws. In vitro experiments [ 9 ] indicated that removing hollow screws did not alter the maximum load of subsequent femoral neck fractures. Finite element experiments [ 10 ] further demonstrated that retained screws exhibited stress concentration and stress shielding effects.…”

Section: Introductionmentioning

confidence: 99%

Biomechanical changes in the proximal femur before and after removal of femoral neck system

Nan,

Liu,

Zhang

et al. 2024

J Orthop Surg Res

View full text Add to dashboard Cite

Background As an innovative internal fixation system, FNS (femoral neck system) is increasingly being utilized by surgeons for the treatment of femoral neck fractures. At present, there have been numerous finite element analysis experiments studying the immediate stability of FNS and CSS in treating femoral neck fractures. However, there is scarce mechanical analysis available regarding the effects post internal fixation removal. This study aimed to investigate the alterations in mechanical parameters of the proximal femur before and after the removal of FNS (femoral neck system), and to assess potential distinctions in indicators following the extraction of CSS (Cannulated Screws). Methods A proximal femur model was reconstructed using finite element numerical techniques. The models for CSS and FNS were formulated utilizing characteristics and parametric definitions. The internal fixation was combined with a normal proximal femur model to simulate the healing state after fracture surgery. Within the framework of static analysis, consistent stress burdens were applied across the entirety of the models. The total deformation and equivalent stress of the proximal femur were recorded before and after the removal of internal fixation. Results Under the standing condition, the total deformation of the model before and after removing CSS was 0.99 mm and 1.10 mm, respectively, indicating an increase of 12%. The total deformation of the model before and after removing FNS was 0.65 mm and 0.76 mm, respectively, indicating an increase of 17%. The equivalent stress for CSS and FNS were 55.21 MPa and 250.67 MPa, respectively. The average equivalent stress on the cross-section of the femoral neck before and after removal of CSS was 7.76 MPa and 6.11 MPa, respectively. The average equivalent stress on the cross-section of the femoral neck before and after removal of FNS was 9.89 MPa and 8.79 MPa, respectively. Conclusions The retention of internal fixation may contribute to improved stability of the proximal femur. However, there still existed risks of stress concentration in internal fixation and stress shielding in the proximal femur. Compared to CSS, the removal of FNS results in larger bone tunnels and insufficient model stability. Further clinical interventions are recommended to address this issue.

show abstract

Section: Introductionmentioning

confidence: 99%

Biomechanical changes in the proximal femur before and after removal of femoral neck system

Nan,

Liu,

Zhang

et al. 2024

J Orthop Surg Res

View full text Add to dashboard Cite

show abstract

Should cannulated screws be removed after a femoral neck fracture has healed, and how? A finite element analysis of the femur before and after cannulated screw removal

Sun

Fang

et al. 2022

International Orthopaedics (SICOT)

View full text Add to dashboard Cite

Análise mecânica após reforço femoral proximal com polimetilmetacrilato em orifícios duplos alternados

Freitas

Lessa²,

Oliveira³

et al. 2020

Rev Bras Ortop (Sao Paulo)

Self Cite

View full text Add to dashboard Cite

Resumo Objetivo Avaliar, por meio de ensaio biomecânico, a carga máxima, a energia, e o deslocamento necessários para a ocorrência de fratura em modelos sintéticos de fêmures após a retirada de parafusos acanulados e a realização de técnica de reforço com polimetilmetacrilato (PMMA) em diferentes posições combinadas. Métodos Foram utilizados 25 ossos sintéticos divididos em 4 grupos: o grupo controle (GC), com 10 modelos sem perfuração, e os grupos teste (A, B e C), com 5 modelos cada. Os grupos de teste foram fixados com parafusos acanulados pela técnica de Asnis, e tiveram a síntese removida e o preenchimento de dois dos orifícios formados por técnica de reforço com PMMA. A análise biomecânica foi realizada simulando queda sobre o grande trocânter utilizando máquina servo-hidráulica. Resultados Todos os corpos de prova do GC e dos grupos A, B e C apresentaram fratura baso-cervical do colo femoral, exceto um modelo do grupo B, que apresentou fratura longitudinal. Foi utilizada uma média de 5,4 mL de PMMA no reforço dos grupos com preenchimento. Segundo a análise de variância (analysis of variance, ANOVA) e o teste de comparações múltiplas de Tukey, no nível de 5%, observou-se que o GC apresentou diferença significativa em relação aos grupos A e C nos seguintes parâmetros: carga máxima, energia até a fratura, e deslocamento. Conclusão Observou-se que os grupos A e C, quando comparados ao GC, apresentaram diferenças significativas na observação do deslocamento, da carga máxima, e da energia até a fratura.

show abstract

Ensaio biomecânico após retirada de parafusos canulados do fêmur proximal (análise in vitro)

Cited by 3 publications

References 16 publications

Biomechanical changes in the proximal femur before and after removal of femoral neck system

Biomechanical changes in the proximal femur before and after removal of femoral neck system

Should cannulated screws be removed after a femoral neck fracture has healed, and how? A finite element analysis of the femur before and after cannulated screw removal

Análise mecânica após reforço femoral proximal com polimetilmetacrilato em orifícios duplos alternados

Contact Info

Product

Resources

About