ABSTRACT
Objective : To compare the function and muscle strength of the limb between patients undergoing knee arthroplasties using primary implants with posterior stabilization (control group) and patients with rotating hinge implants (Hinge group). Methods : Function assessment was performed using the Knee Society Score (KSS) and muscle strength using an isokinetic dynamometer using a speed of 60°/s. Results : 43 patients were analyzed, who underwent 51 surgeries, with the Hinge group comprising 25 surgeries and the control group comprising 26 primary surgeries. We did not observe significant differences between the Hinge and control groups in the values of functional KSS (p = 0.54), objective KSS (p = 0.91), peak flexor torque (p = 0.25) and peak extensor torque (p = 0.08). Patients in the Hinge group who underwent primary arthroplasties had a higher peak flexor torque (0.76 Nm/kg) than those who used the implant in revision after septic failure (0.33 Nm/kg) (p < 0.05). The constrained implant was indicated in arthroplasty revision surgeries with severe ligament instability and in cases of complex primary arthroplasties with bone destruction or severe coronal deformity in the coronal plane. Conclusion : The use of constrained implants enables joint function and muscle strength comparable to patients who underwent primary arthroplasty using conventional implants with posterior stabilization. Patients undergoing septic revision with a rotating Hinge prosthesis exhibit lower flexor muscle strength compared to those undergoing primary arthroplasty with a constrained implant.
ABSTRACT
Abstract Objective: To compare the function and muscle strength of the limb between patients undergoing knee arthroplasties using primary implants with posterior stabilization (control group) and patients with rotating hinge implants (Hinge group). Methods: Function assessment was performed using the Knee Society Score (KSS) and muscle strength using an isokinetic dynamometer using a speed of 60°/s. Results: 43 patients were analyzed, who underwent 51 surgeries, with the Hinge group comprising 25 surgeries and the control group comprising 26 primary surgeries. We did not observe significant differences between the Hinge and control groups in the values of functional KSS (p = 0.54), objective KSS (p = 0.91), peak flexor torque (p = 0.25) and peak extensor torque (p = 0.08). Patients in the Hinge group who underwent primary arthroplasties had a higher peak flexor torque (0.76 Nm/kg) than those who used the implant in revision after septic failure (0.33 Nm/kg) (p <0.05). The constrained implant was indicated in arthroplasty revision surgeries with severe ligament instability and in cases of complex primary arthroplasties with bone destruction or severe coronal deformity in the coronal plane. Conclusion: The use of constrained implants enables joint function and muscle strength comparable to patients who underwent primary arthroplasty using conventional implants with posterior stabilization. Patients undergoing septic revision with a rotating Hinge prosthesis exhibit lower flexor muscle strength compared to those undergoing primary arthroplasty with a constrained implant.
Resumo Objetivo: Comparar a função e a força muscular do membro entre pacientes submetidos a artroplastias do joelho que utilizaram implantes primários com estabilização posterior (grupo controle) e pacientes com implantes constritos rotatórios (grupo Hinge). Métodos: A avaliação da função foi feita por meio do Knee Society Score (KSS) e da força muscular por um dinamômetro isocinético utilizando a velocidade de 60°/s. Resultados: Foram analisados 43 pacientes, que realizaram 51 cirurgias, sendo o grupo Hinge composto por 25 cirurgias e o grupo controle por 26 cirurgias primárias. Não observamos diferenças significativas entre os grupos Hinge e controle nos valores do KSS funcional (p = 0,54), KSS objetivo (p = 0,91), pico de torque flexor (p = 0,25) e pico de torque extensor (p =0,08). Os pacientes do grupo Hinge que realizaram artro-plastias primárias apresentaram um pico de torque flexor maior (0,76 Nm/kg) que aqueles que utilizaram o implante em revisão após falha séptica (0,33 Nm/kg) (p < 0,05). O implante constrito foi indicado em cirurgias de revisão de artroplastia com instabilidade ligamentar grave e em casos de artroplastias primárias complexas com destruição óssea ou deformidade coronal grave no plano coronal. Conclusão: O uso de implantes bloqueados possibilita função articular e força muscular comparáveis a dos pacientes que realizaram artroplastia primária utilizando implantes convencionais com estabilização posterior. Pacientes submetidos à revisão séptica com prótese Hinge rotatória apresentam menor força da musculatura flexora em relação àqueles submetidos a artroplastia primária com implante constrito.
