Comparative Functional and Isokinetic Analysis between Implants with Posterior Stabilization and Rotating Hinge Total Knee Arthroplasty.

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.

Comparative Functional and Isokinetic Analysis between Implants with Posterior Stabilization and Rotating Hinge Total Knee Arthroplasty / Análise funcional e isocinética comparativa entre implantes com estabilização posterior e rotatórios constritos (hinge) em artroplastias do joelho

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.

Accuracy of Serological Markers, Synovial Fluid, Microbiological Culture, and Histopathological Examination for Diagnosing Periprosthetic Knee Infection.

Objective This study assessed the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of serological tests, synovial fluid markers, microbiological tissue culture, and histopathological examination of the periprosthetic membrane in diagnosing periprosthetic knee infection. Methods This study is prospective, and it includes patients undergoing total knee arthroplasty revision surgery from November 2019 to December 2021. The analysis consisted of serological tests (erythrocyte sedimentation rate [ESR], C-reactive protein [CRP], and D-dimer), synovial fluid markers (leukocyte and polymorphonuclear cell counts), periprosthetic tissue culture, and histopathological examination of the periprosthetic membrane of all patients. Results Sixty-two patients had periprosthetic joint infection (PJI) according to the 2018 International Consensus Meeting criteria (infection group), while 22 subjects had no infection. ESR sensitivity and specificity were 83.6% and 45.4%, respectively. CRP sensitivity and specificity were 64.5% and 100%, whereas D-dimer sensitivity and specificity were 78.9% and 25%, respectively. Leukocyte count sensitivity and specificity were 75.6% and 100%, polymorphonuclear cell count sensitivity and specificity were 33% and 100%, respectively. Periprosthetic tissue culture sensitivity and specificity culture were, respectively, 77.4% and 100%. Histopathological examination sensitivity and specificity were 43.7% and 100%, respectively. Conclusions In our study, the total blood cell count in synovial fluid and microbiological cultures of periprosthetic tissues were the most accurate tests for PJI diagnosis. In contrast, polymorphonuclear cell percentage was the least accurate test for PJI diagnosis.

Continuous Vertical Inside-Out Versus Traditional Vertical Inside-Out Meniscal Repair: A Biomechanical Comparison.

Background: Biomechanical assessment of meniscal repairs is essential for evaluating different meniscal suturing methods and techniques. The continuous meniscal suture technique is a newer method of meniscal repair that may have biomechanical differences compared with traditional techniques. Purpose: To evaluate the displacement, stiffness after cyclical loading, and load to failure for a continuous vertical inside-out meniscal suture versus a traditional vertical inside-out meniscal suture in a porcine medial meniscus. Study Design: Controlled laboratory study. Methods: A total of 28 porcine knees were acquired and divided into 2 test groups of 14 medial meniscus each. A 2.0-cm longitudinal red-white zone cut was made in the body of the medial meniscus for each knee. The continuous suture (CS) group received 4 vertical stitches performed with a continuous vertical meniscal suture technique, and the inside-out suture (IO) group received a traditional vertical suture with 4 stitches. Two traction tapes were passed between the sutures and positioned in the biomechanical testing fixture device. Each specimen underwent load-to-failure testing at 5 mm/s, and displacement, system stiffness, and maximum load to failure were compared between the groups. Results: The displacement after the cyclic test was 0.53 ± 0.12 and 0.48 ± 0.07 mm for the CS and IO groups, respectively. There was no significant difference between the groups (P = .2792). The stiffness at the ultimate load testing was 36.3 ± 1.9 and 35.3 ± 2.4 N/mm for groups CS and IO, respectively, with no significant difference between the groups (P = .2557). In the load-to-failure test, the ultimate load was 218.2 ± 63.9 and 238.3 ± 71.3 N in the CS and IO groups, respectively, with no significant group differences (P = .3062). Conclusion: A continuous vertical meniscal suture created a configuration for treating longitudinal meniscal lesions that was beneficial and biomechanically similar to a traditional vertical suture technique. Clinical Relevance: The study findings indicate that use of the continuous vertical inside-out meniscal suture technique is a possible therapeutic option.

Microbiological Profile of Periprosthetic Knee Infections in a Brazilian Unified Health System Hospital Specialized in Highly Complex Orthopedic Surgeries.

Objective We studied the microbiological profile of periprosthetic knee infections treated in a Brazilian tertiary hospital. Methods The study included all patients undergoing revision surgery for total knee arthroplasty (RTKA) between November 2019 and December 2021, with a diagnosis of periprosthetic infection confirmed per the 2018 International Consensus Meeting (ICM) criteria. Results Sixty-two patients had a periprosthetic joint infection (PJI) per the 2018 ICM criteria. Cultures were monomicrobial in 79% and polymicrobial in 21% of cases. The most frequent bacterium in microbiological tissue and synovial fluid cultures was Staphylococcus aureus , observed in 26% of PJI patients. Periprosthetic joint infection with negative cultures occurred in 23% of patients. Conclusion Our results show the following: i) a high prevalence of Staphylococcus as an etiological agent for knee PJI; ii) a high incidence of polymicrobial infections in early infections; iii) the occurrence of PJI with negative cultures in approximately one fourth of the subjects.

Microbiological Profi le of Periprosthetic Knee Infections in a Brazilian Unified Health System Hospital Specialized in Highly Complex Orthopedic Surgeries / Perfil microbiológico das infecções periprotéticas do joelho em um hospital do Sistema Único de Saúde especializado em cirurgias ortopédicas de alta complexidade

Abstract Objective We studied the microbiological profile of periprosthetic knee infections treated in a Brazilian tertiary hospital. Methods The study included all patients undergoing revision surgery for total knee arthroplasty (RTKA) between November 2019 and December 2021, with a diagnosis of periprosthetic infection confirmed per the 2018 International Consensus Meeting (ICM) criteria. Results Sixty-two patients had a periprosthetic joint infection (PJI) per the 2018 ICM criteria. Cultures were monomicrobial in 79% and polymicrobial in 21% of cases. The most frequent bacterium in microbiological tissue and synovial fluid cultures was Staphylococcus aureus, observed in 26% of PJI patients. Periprosthetic joint infection with negative cultures occurred in 23% of patients. Conclusion Our results show the following: i) a high prevalence of Staphylococcus as an etiological agent for knee PJI; ii) a high incidence of polymicrobial infections in early infections; iii) the occurrence of PJI with negative cultures in approximately one fourth of the subjects.

Resumo Objetivo Identificar o perfil microbiológico das infecções periprotéticas do joelho tratadas em um hospital terciário brasileiro. Métodos Todos os pacientes submetidos à cirurgia de revisão de artroplastia total do joelho (RATJ), no período compreendido entre novembro de 2019 e dezembro de 2021, e que tiveram o diagnóstico de infecção periprotética confirmado de acordo com critérios do International Consensus Meeting (ICM) 2018, foram incluídos no estudo. Resultados Sessenta e dois pacientes foram diagnosticados com infecção periprotética (IAP) pelos critérios do International Consensus Meeting 2018. Culturas monomicrobianas foram identificadas em 79% e polimicrobianas em 21% dos casos. A bactéria mais frequentemente identificada nas culturas microbiológicas de tecidos e líquido sinovial foi o Staphylococcus aureus, presente em 26% dos pacientes com infecção periprotética. Infecções periprotéticas com culturas negativas ocorreram em 23% dos pacientes. Conclusão Nossos resultados evidenciam: i) alta prevalência de bactérias do gênero Staphylococcus como causadores da IAP do joelho; ii) a alta incidência de infecções polimicrobianas nas infecções precoces e iii) IAP com culturas negativas ocorre em, aproximadamente, um quarto dos pacientes.

Accuracy of Serological Markers, Synovial Fluid, Microbiological Culture, and Histopathological Examination for Diagnosing Periprosthetic Knee Infection / Acurácia dosmarcadores sorológicos, do líquido sinovial, cultura microbiológica e exame histopatológico para o diagnóstico de infecção periprotética do joelho

Abstract Objective This study assessed the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of serological tests, synovial fluid markers, microbiological tissue culture, and histopathological examination of the periprosthetic membrane in diagnosing periprosthetic knee infection. Methods This study is prospective, and it includes patients undergoing total knee arthroplasty revision surgery from November 2019 to December 2021. The analysis consisted of serological tests (erythrocyte sedimentation rate [ESR], C-reactive protein [CRP], and D-dimer), synovial fluid markers (leukocyte and polymorphonuclear cell counts), periprosthetic tissue culture, and histopathological examination of the periprosthetic membrane of all patients. Results Sixty-two patients had periprosthetic joint infection (PJI) according to the 2018 International Consensus Meeting criteria (infection group), while 22 subjects had no infection. ESR sensitivity and specificity were 83.6% and 45.4%, respectively. CRP sensitivity and specificity were 64.5% and 100%, whereas D-dimer sensitivity and specificity were 78.9% and 25%, respectively. Leukocyte count sensitivity and specificity were 75.6% and 100%, polymorphonuclear cell count sensitivity and specificity were 33% and 100%, respectively. Periprosthetic tissue culture sensitivity and specificity culture were, respectively, 77.4% and 100%. Histopathological examination sensitivity and specificity were 43.7% and 100%, respectively. Conclusions In our study, the total blood cell count in synovial fluid and microbiological cultures of periprosthetic tissues were the most accurate tests for PJI diagnosis. In contrast, polymorphonuclear cell percentage was the least accurate test for PJI diagnosis.

Resumo Objetivo avaliar a sensibilidade, especificidade, valor preditivo positivo, valor preditivo negativo e acurácia dos testes sorológicos, dos marcadores do líquido sinovial, da cultura microbiológica de tecidos e do exame histopatológico da membrana periprotética para o diagnóstico de infecção periprotética do joelho. Métodos estudo prospectivo, com pacientes submetidos à cirurgia de revisão de artroplastia total do joelho no período entre novembro de 2019 e dezembro de 2021. Foi realizado análise do marcadores sorológicos (VHS,PCR e D-dímero), do líquido sinovial (contagem de leucócitos e percentual de polimorfonucleares), cultura de tecidos periprotéticos e exame histopatológico da membrana periprotética de todos os pacientes. Resultados 62 pacientes foram diagnosticados com infecção periprotética do joelho, pelos critérios do International Consensus Meeting 2018 (grupo infecção) e 22 pacientes integraram o grupo não infecção. A sensibilidade e especificidade da VHS foram de 83,6% e 45,4%, respectivamente. Os valores de sensibilidade e especificidade da PCR foram de 64,5% e 100% e as do D-dímero foram de 78,9%% e 25%, respectivamente. A sensibilidade e especificidade da contagem de leucócitos foi de 75,6% e 100%, e a do percentual de polimorfonucleares foi de 33% e 100%, respectivamente. A sensibilidade e especificidade das culturas de tecidos periprotéticos foi de, respectivamente, 77,4% e 100% A sensibilidade do exame histopatológico foi de 43,7% e a especificidade de 100%. Conclusões A contagem total de leucócitos no líquido sinovial e as culturas microbiológicas dos tecidos periprotéticos foram os testes de maior acurácia para o diagnóstico de infecção periprotética em nossa série. O percentual de polimorfonucleares foi o teste de menor acurácia, em nosso estudo, para o diagnóstico de infecção periprotética.

Midterm Radiographic Results and Reoperations of Tantalum Trabecular Metal Cones in Knee Arthroplasties.

Objective The management of bone loss represents a challenge in revisions of total knee arthroplasty (rTKA) and in complex primary total knee arthroplasties (TKAs). The purpose of the present study was to evaluate the midterm outcomes (5-year minimum follow-up) of knee reconstructions with tantalum trabecular metal (TM) cones on bone defects Anderson Orthopaedics Research Institute (AORI) 2 and 3. Materials and Methods A retrospective analysis of the medical records of patients operated on between July 2008 and November 2014 was performed, collecting the following data: age, gender, laterality, body mass index, etiology of arthrosis, comorbidities, AORI classification of bone defects, causes for revision, readmissions, reoperations, perioperative and postoperative complications, radiographic signs of osteointegration, and maintenance of the TM support. Results A total of 11 patients with a mean follow-up of 7.28 years (standard deviation [SD] = 1.88; range = 5.12-10 years) was evaluated, with 1 patient operated upon for a primary arthroplasty, 6 for revision arthroplasties, and 4 for a second revision arthroplasty (re-revision). There were complications with the surgical wound, injury to the extensor mechanism and loosening of the femoral component in three of the patients that led to the necessity of four procedures due to complications with the surgical wound, injury to the extensor mechanism and loosening of the femoral component. Radiological signs of osteointegration of the trabecular cones were observed in all patients. We did not observe migration of the TM cones or the prosthetic components in the sample. Conclusion The tantalum metaphyseal cones were able to provide efficient structural support to prosthetic implants with radiographic signs of osteointegration in the medium term.

Midterm Radiographic Results and Reoperations of Tantalum Trabecular Metal Cones in Knee Arthroplasties / Reoperações e resultados radiográficos de médio prazo do uso de cone de metal trabecular de tântalo nas artroplastias do joelho

Abstract Objective The management of bone loss represents a challenge in revisions of total knee arthroplasty (rTKA) and in complex primary total knee arthroplasties (TKAs). The purpose of the present study was to evaluate the midterm outcomes (5-year minimum follow-up) of knee reconstructions with tantalum trabecular metal (TM) cones on bone defects Anderson Orthopaedics Research Institute (AORI) 2 and 3. Materials and MethodsA retrospective analysis of the medical records of patients operated on between July 2008 and November 2014 was performed, collecting the following data: age, gender, laterality, body mass index, etiology of arthrosis, comorbidities, AORI classification of bone defects, causes for revision, readmissions, reoperations, perioperative and postoperative complications, radiographic signs of osteointegration, and maintenance of the TM support. Results A total of 11 patients with a mean follow-up of 7.28 years (standard deviation [SD] = 1.88; range = 5.12-10 years) was evaluated, with 1 patient operated upon for a primary arthroplasty, 6 for revision arthroplasties, and 4 for a second revision arthroplasty (re-revision). There were complications with the surgical wound, injury to the extensor mechanism and loosening of the femoral component in three of the patients that led to the necessity of four procedures due to complications with the surgical wound, injury to the extensor mechanism and loosening of the femoral component. Radiological signs of osteointegration of the trabecular cones were observed in all patients. We did not observe migration of the TM cones or the prosthetic components in the sample. Conclusion The tantalum metaphyseal cones were able to provide efficient structural support to prosthetic implants with radiographic signs of osteointegration in the medium term.

Resumo Objetivo O manejo da perda óssea representa um grande desafio em cirurgias de revisão de artroplastia do joelho (rATJ) e em artroplastias totais do joelho (ATJ) primárias complexas. O objetivo do presente estudo foi avaliar os resultados em médio prazo (seguimento mínimo de 5 anos) das reconstruções de joelho nas quais cones de metal trabecular (MT) de tântalo foram utilizados para tratamento de defeitos ósseos tipos 2 e 3, de acordo com a classificação proposta pela Anderson Orthopaedic Research Institute (AORI). Métodos Feita análise retrospectiva dos prontuários dos pacientes operados entre julho de 2008 e novembro de 2014, coletando-se os seguintes dados: idade, gênero, lateralidade, índice de massa corporal, etiologia da artrose, comorbidade, classificação AORI da falha óssea, causa da revisão da artroplastia total do joelho, reinternações, reoperações, complicações peri- e pós-operatórias, ocorrência de osteointegração radiográfica e manutenção da função de suporte do MT. Resultados Foram avaliados 11 pacientes com tempo médio de seguimento de 7,28 anos (desvio padrão [DP] = 1,88; variação = 5,12-10 anos), sendo que 1 paciente foi submetido a artroplastia primária, 6 a artroplastia de revisão e 4 a segunda revisão de artroplastia (re-revisão). Três pacientes necessitaram de quatro reoperações devido a complicações com a ferida operatória, a lesão do mecanismo extensor e a soltura do componente femoral. Sinais de osteointegração dos cones trabeculados foram observados em todos os pacientes. Não observamos migração do cone de MT ou dos componentes protéticos. Conclusão Os cones metafisários de tântalo foram capazes de prover suporte estrutural eficiente aos implantes protéticos com sinais radiográficos de osteointegração em médio prazo.

EXTENSOR MECHANISM TRANSPLANTATION AFTER KNEE PROSTHESIS: 70-MONTH FOLLOW-UP.

Objective: This article reports the range of motion, failure rate, and complications of patients with extensor mechanism injury after total knee arthroplasty (TKA) treated with extensor mechanism allograft with mid-term follow-up. Methods: Patients undergoing post-ATJ extensor mechanism transplantation from 2009 to 2018 were retrospectively evaluated. Demographics, the reason for transplantation, elapsed time from arthroplasty to transplantation, related surgical factors, immobilization time, range of motion, transplant failure, and complications were collected. The minimum follow-up was 24 months. Results: Twenty patients were evaluated. The mean follow-up was 70.8 +/- 33.6 months. The most common cause of extensor mechanism rupture was traumatic in 10 (50%) cases. Six patients underwent associated surgeries, one case of medial ligament complex reconstruction, and 5 cases of TKA revision. Eleven patients (55%) had transplant-related complications. The most common complication was an infection. Five cases presented transplant failure. Conclusion: Patients who underwent extensor mechanism allograft transplantation after total knee arthroplasty had a 25% failure rate with a mean follow-up of 6 years. Although there was no loss of flexion with the procedure and prolonged immobilization, the complication rate was not low. Level of evidence IV; case series .

Objetivo: O objetivo do estudo foi relatar amplitude de movimento, taxa de falha e complicações de pacientes com lesão do mecanismo extensor após artroplastia total do joelho (ATJ) tratados com aloenxerto do mecanismo extensor com acompanhamento no médio prazo. Métodos: Pacientes submetidos a transplante de mecanismo extensor pós-ATJ de 2009 a 2018 foram avaliados retrospectivamente. Foram avaliados dados demográficos, motivo do transplante, tempo decorrido da artroplastia ao transplante, fatores cirúrgicos relacionados, tempo de imobilização, arco de movimento, falha do transplante e complicações. O acompanhamento mínimo foi de 24 meses. Resultados: Vinte pacientes foram avaliados. O tempo médio de acompanhamento foi de 70,8 +/- 33,6 meses. A causa mais comum de ruptura do mecanismo extensor foi traumática em 10 (50%) casos. Seis pacientes foram submetidos a cirurgias associadas, um caso de reconstrução do complexo ligamentar medial e 5 casos de revisão de ATJ. Onze pacientes (55%) tiveram complicações relacionadas ao transplante. A complicação mais comum foi a infecção. Cinco casos apresentaram falha do transplante. Conclusão: Pacientes submetidos a transplante de aloenxerto de mecanismo extensor após artroplastia total de joelho apresentam taxa de falha de 25% com seguimento médio de 6 anos. Embora não tenha havido perda de flexão com o procedimento e com a imobilização prolongada, o índice de complicações não foi baixo. Nível de evidênvia IV; série de casos .

Pulsed Radiofrequency Rhizotomy of the Genicular Nerves of the Knee Guided by Radioscopy and Ultrasonography: Step-By-Step Technique.

Osteoarthritis (OA) of the knee is highly prevalent and causes pain, stiffness, and harms the quality of life of millions of patients. Scientific evidence about radiofrequency ablation or rhizotomy of genicular nerves has been presented with increasing frequency in the literature for the treatment of chronic pain related to knee OA as an alternative to total knee arthroplasty. The main indication for this procedure is symptomatic OA unresponsive to conservative treatment, regardless of the disease evolution, although more common indications are in Kellgren-Lawrence grade III or IV, in post-total knee arthroplasty residual pain without an identified cause, in patients with comorbidities and high surgical risk, and those who do not want to undergo surgery. The aim of this study is to describe the step-by-step rhizotomy technique with pulsed radiofrequency of the 3 genicular nerves, guided by radioscopy and ultrasonography.

Modified Pulvertaft on Weave Technique Restores Full Active Knee Extension in Patients With Large Chronic Quadriceps Tendon Rupture: A Case Series.

PURPOSE: We aimed to investigate the clinical and functional outcomes, including maximal and explosive strength, after chronic quadriceps tendon rupture repair with Modified Pulvertaft on Weave (MPW) technique METHODS: Knee joint range of motion (ROM), patella height, thigh circumference, and Lysholm and International Knee Documentation Committee (IKDC) scores were assessed preoperatively and postoperatively. The knee extensors maximal (isokinetic peak torque and isometric maximal voluntary contraction (MVC) torque) and explosive strength-rate of torque development (RTD) early [RTD50 and RTD100] and late [RTD250]-were performed. We assessed the thigh circumference and vastus lateralis muscle thickness (MT) as indicators of quadriceps muscle mass, and the voluntary quadriceps activation using surface electromyography (EMG50). RESULTS: Nine patients (mean age: 53 ± 11 years) took part in the study. We observed a significant increase in the knee active ROM and a decreased extension deficit (both, P < .001), but not for pain (P = .07), IKDC (P = .07), and Lysholm (P = .21) after the surgery. We did not observe a difference between involved (n = 8) and uninvolved (n = 10) limbs for ROM, thigh circumference, and MT. We observed differences for extensors peak torque, MVC torque, and late RTD (all, P < .05). However, we did not observe differences for early RTD and EMG50. Significant positive correlations were observed for RTD50 (ρ = .80) and RTD100 (ρ = .81) vs EMG50. Both the IKDC and Lysholm were better correlated with the early than with later RTD. CONCLUSIONS: The MPW reestablished the active knee extension. The same level of quadriceps muscle mass was observed in both limbs, suggesting a lack of hypotrophy due to the injury. Although the involved limb had demonstrated lower knee extensors maximal strength, they demonstrate an equivalent early RTD when compared to the uninvolved limb. The early RTD seems to be better correlated with the patient's functionality than the later RTD and maximal strength. LEVEL OF EVIDENCE: IV, case series.

Extensor mechanism transplantation after knee prosthesis: 70-month follow-up / Transplante de mecanismo extensor após prótese de joelho: seguimento 70 meses

ABSTRACT Objective: This article reports the range of motion, failure rate, and complications of patients with extensor mechanism injury after total knee arthroplasty (TKA) treated with extensor mechanism allograft with mid-term follow-up. Methods: Patients undergoing post-ATJ extensor mechanism transplantation from 2009 to 2018 were retrospectively evaluated. Demographics, the reason for transplantation, elapsed time from arthroplasty to transplantation, related surgical factors, immobilization time, range of motion, transplant failure, and complications were collected. The minimum follow-up was 24 months. Results: Twenty patients were evaluated. The mean follow-up was 70.8 +/- 33.6 months. The most common cause of extensor mechanism rupture was traumatic in 10 (50%) cases. Six patients underwent associated surgeries, one case of medial ligament complex reconstruction, and 5 cases of TKA revision. Eleven patients (55%) had transplant-related complications. The most common complication was an infection. Five cases presented transplant failure. Conclusion: Patients who underwent extensor mechanism allograft transplantation after total knee arthroplasty had a 25% failure rate with a mean follow-up of 6 years. Although there was no loss of flexion with the procedure and prolonged immobilization, the complication rate was not low. Level of evidence IV; case series .

RESUMO Objetivo: O objetivo do estudo foi relatar amplitude de movimento, taxa de falha e complicações de pacientes com lesão do mecanismo extensor após artroplastia total do joelho (ATJ) tratados com aloenxerto do mecanismo extensor com acompanhamento no médio prazo. Métodos: Pacientes submetidos a transplante de mecanismo extensor pós-ATJ de 2009 a 2018 foram avaliados retrospectivamente. Foram avaliados dados demográficos, motivo do transplante, tempo decorrido da artroplastia ao transplante, fatores cirúrgicos relacionados, tempo de imobilização, arco de movimento, falha do transplante e complicações. O acompanhamento mínimo foi de 24 meses. Resultados: Vinte pacientes foram avaliados. O tempo médio de acompanhamento foi de 70,8 +/- 33,6 meses. A causa mais comum de ruptura do mecanismo extensor foi traumática em 10 (50%) casos. Seis pacientes foram submetidos a cirurgias associadas, um caso de reconstrução do complexo ligamentar medial e 5 casos de revisão de ATJ. Onze pacientes (55%) tiveram complicações relacionadas ao transplante. A complicação mais comum foi a infecção. Cinco casos apresentaram falha do transplante. Conclusão: Pacientes submetidos a transplante de aloenxerto de mecanismo extensor após artroplastia total de joelho apresentam taxa de falha de 25% com seguimento médio de 6 anos. Embora não tenha havido perda de flexão com o procedimento e com a imobilização prolongada, o índice de complicações não foi baixo. Nível de evidênvia IV; série de casos .

Infection after primary total knee arthroplasty: a randomized controlled prospective study of the addition of antibiotics to bone cement.

Objective The present prospective, randomized and controlled study was conducted with 286 patients submitted to primary total knee arthroplasty (TKA) with the objective of evaluating the efficacy of the addition of antibiotics to bone cement as a way to prevent post arthroplasty infection (PAI). Methods The patients were randomized into two groups: bone cement without antibiotic (No ATB, n = 158) or cement with antibiotic (ATB, n = 128), in which 2 g of vancomycin was added to 40 g of cement. The patients were followed up for 24 months after surgery. Results Regarding preoperative demographic data, the distribution of patients between groups was homogeneous ( p < 0.05). In the 24-month period, the overall infection rate was of 2.09% (6/286), with no difference (odds ratio [OR] = 1.636; 95% confidence interval [CI]: 0.294-9.080; p = 0.694) between the ATB group (1.56%; 2/128) and the No ATB group (2.53%; 4/158). In the No ATB group, the infection was caused by methicillin-resistant Staphylococcus aureus (MRSA) ( n = 2), methicillin-sensitive S. aureus (MSSA) ( n = 1) and Eschirichia coli ( n = 1). Proteus mirabilis and MSSA were isolated from patients in the ATB group. Among the comorbidities, all patients with PAI were hypertensive and nondiabetic. Two rheumatoid arthritis patients who developed PAI were from the ATB group. Conclusion The use of cement with ATB reduced the absolute number of infections, but without statistical difference between the groups; thus, routine use should not be encouraged.

Predictive Factors for Blood Transfusion after Total Knee Arthroplasty.

Objectives The present paper aims to (1) verify the incidence and volume of blood transfusion among patients undergoing unilateral cemented total knee arthroplasty (TKA) in a single Brazilian reference center; (2) identify pre and perioperative variables to determine subjects with higher risk (i.e., predictive factors) for blood transfusion within 48 hours following surgery; (3) estimate the risk of blood transfusion during the first 48 hours after the procedure. Methods The initial sample consisted of all patients undergoing TKA from August 2010 to August 2013. After applying the exclusion criteria, 234 patients aged 30 to 83 years old and diagnosed with primary or secondary osteoarthritis due to rheumatoid arthritis remained in the study. Results Preoperative hemoglobin levels ≤ 12.3 g/dL and ischemia time ≥ 87 minutes were independent predictors for post-TKA blood transfusion, with a relative risk of 2.48 and 1.78, respectively. Approximately half of the TKA patients (51.3%) presenting these two variables required a blood transfusion. Conclusion The incidence of post-TKA blood transfusion was 33.7%. On average, each transfused patient received 480 mL of packed red blood cells. Preoperative hemoglobin levels ≤ 12.3 g/dL ( p < 0.001) and ischemia time ≥ 87 minutes ( p < 0.047) were independent predictors for blood transfusion in TKA using a pneumatic cuff, with a relative risk of 2.48 and 1.78, respectively. Age, gender, diagnosis, or body mass index were not considered independent predictors for the need for blood transfusion up to 48 hours after the procedure.

Continuous Meniscal Suture in Radial Meniscal Tear: The Hourglass Technique.

The key to preventing early knee osteoarthritis is meniscal preservation. The main functions of the meniscus are impact absorption, mechanical load transmission, lubrication, joint stability, and proprioception. Radial lesions that extend to the joint capsule are called complete radial tears. This type of injury compromises 2 of the main meniscal functions, which are impact absorption and load distribution, which is equivalent, from a biomechanical perspective, to a total meniscectomy. In the recent past, the treatment of choice for this type of injury was partial meniscectomy. However, several studies have observed progressive joint degeneration after this type of treatment. Recently, different types of meniscal sutures involving radial lesions of the meniscus have been developed. It is believed that such repairs may bring a decrease in future osteoarthritis in this patient profile. The purpose of this article is to describe the steps of continuous meniscal suture for the treatment of radial tears of the medial and lateral menisci.

How to Create an Arthroscopy Training Laboratory Using a Bovine Knee Model.

Orthopaedic surgeries by video arthroscopy have become increasingly popular, as they allow joint treatment through small incisions and minimal tissue damage. However, their execution requires specific skills from the surgeon, different from open surgery, which can only be achieved through practical training. These skills would be ideally performed on human cadaveric anatomical pieces which, however, can be difficult to access for different reasons. Animal anatomical models for surgical skills training have been used for years in medicine, and we observed that the bovine knee has anatomical characteristics quite similar to that of the human knee. In this study, we explain, step by step, the installation and creation of an arthroscopy laboratory with a bovine model, in an effort to contribute to several training centers in arthroscopic surgery around the world, assisting and guiding such centers to install arthroscopy laboratories and facilitating the improvement of more surgeons.

Predictive Factors for Blood Transfusion after Total Knee Arthroplasty / Fatores preditivos de hemotransfusão após artroplastia total de joelho

Abstract Objectives The present paper aims to (1) verify the incidence and volume of blood transfusion among patients undergoing unilateral cemented total knee arthroplasty (TKA) in a single Brazilian reference center; (2) identify pre and perioperative variables to determine subjects with higher risk (i.e., predictive factors) for blood transfusion within 48 hours following surgery; (3) estimate the risk of blood transfusion during the first 48 hours after the procedure. Methods The initial sample consisted of all patients undergoing TKA from August 2010 to August 2013. After applying the exclusion criteria, 234 patients aged 30 to 83 years old and diagnosed with primary or secondary osteoarthritis due to rheumatoid arthritis remained in the study. Results Preoperative hemoglobin levels ≤12.3 g/dL and ischemia time ≥87 minutes were independent predictors for post-TKA blood transfusion, with a relative risk of 2.48 and 1.78, respectively. Approximately half of the TKA patients (51.3%) presenting these two variables required a blood transfusion. Conclusion The incidence of post-TKA blood transfusion was 33.7%. On average, each transfused patient received 480 mL of packed red blood cells. Preoperative hemoglobin levels ≤12.3 g/dL (p < 0.001) and ischemia time ≥87 minutes (p < 0.047) were independent predictors for blood transfusion in TKA using a pneumatic cuff, with a relative risk of 2.48 and 1.78, respectively. Age, gender, diagnosis, or body mass index were not considered independent predictors for the need for blood transfusion upto 48 hours after the procedure.

Resumo Objetivos O presente estudo tem como objetivos (1) verificar a incidência e o volume de transfusão sanguínea entre os pacientes submetidos à artroplastia total do joelho (ATJ) unilateral cimentada em um único centro de referência nacional; (2) identificar variáveis pré e perioperatórias que nos permitam identificar os indivíduos sob maior risco (fatores preditores) quanto à necessidade de transfusão sanguínea nas 48 horas subsequentes à realização da cirurgia; (3) estimar o risco de transfusão sanguínea durante as primeiras 48 horas após o procedimento. Métodos A amostra inicial foi constituída por todos os pacientes submetidos à ATJ entre agosto de 2010 e agosto de 2013. Após aplicação dos critérios de exclusão, permaneceram no estudo 234 pacientes com idade entre 30 e 83 anos, portadores de osteaoartrose primária ou secundária a artrite reumatoide. Resultados A análise dos resultados mostrou que valores de hemoglobina préoperatória ≤12,3 g/dL e tempo de isquemia ≥87 minutos são preditores independentes para hemotransfusão após ATJ, com risco relativo de 2,48 e 1,78, respectivamente. Aproximadamente metade dos pacientes (51,3%) submetidos a ATJ com essas duas variáveis necessitaram de hemotransfusão. Conclusão A incidência de transfusão sanguínea após ATJ foi de 33,7%. Em média, cada paciente foi transfundido com 480 mL de concentrado de hemácias. Concentração de hemoglobina pré-operatória ≤12,3 g/dL (p < 0,001) e tempo de isquemia ≥87 minutos (p < 0,047) foram preditores independentes para hemotransfusão em ATJ sob uso de manguito pneumático, com risco relativo de 2,48 e 1,78, respectivamente. A idade, o gênero, diagnóstico ou índice de massa corporal não foram considerados preditores independentes para a necessidade de hemotransfusão até 48 horas após o procedimento de artroplastia.

Posterior Root Repair of Medial Meniscus Combined With Valgus Opening Wedge Tibial Osteotomy.

The medial meniscal root tear, a particular meniscal injury at the level of its posterior bone insertion, leads to a loss of impact absorption and load distribution capacity, similar to total meniscectomy. Therefore, its repair is fundamental for knee joint longevity. This type of injury often occurs in middle-aged patients with lower limbs varus malalignment, which results in mechanical overloading of the medial compartment and induces premature cartilage wear out. The success of meniscal root repair, with meniscal bone reinsertion, depends on the correction and realignment of varus deformities greater than 5° for physiological levels. In this situation, corrective tibial osteotomy combined with meniscal repair is indicated. Our goal is to describe the step-by-step technique of the valgus opening wedge tibial osteotomy combined with the arthroscopic reinsertion of the posterior meniscal root in tibia during the treatment of a patient with varus deformity and medial meniscus root tear.

Bone Defects in Revision Total Knee Arthroplasty.

The increase in the number of revision total knee arthroplasty surgeries has been observed in recent years, worldwide, for several causes. In the United States, a 601% increase in the number of total knee arthroplasties, between 2005 and 2030, is estimated. Among the enormous challenges of this complex surgery, the adequate treatment of bone defects is essential to obtain satisfactory and lasting results. The adequate treatment of bone defects aims to build a stable and lasting support platform for the implantation of the definitive prosthetic components and, if possible, with the reconstruction of bone stock. Concomitantly, it allows the correct alignment of the prosthetic and limb components, as well as restoring the height of the joint interline and, thus, restoring the tension of soft parts and load distribution to the host bone, generating a joint reconstruction with good function, stable, and painless. There are several options for the management of these bone defects, among them: bone cement with or without reinforcement with screws, modular metallic augmentations, impacted bone graft, structural homologous graft and, more recently, metal metaphyseal cones, and metaphyseal sleeves. The objective of the present article was to gather classic information and innovations about the main aspects related to the treatment of bone defects during revision surgeries for total knee arthroplasty.