Influence of Human Bone Marrow Mesenchymal Stem Cells Secretome from Acute Myeloid Leukemia Patients on the Proliferation and Death of K562 and K562-Lucena Leukemia Cell Lineages.

Leukemias are among the most prevalent types of cancer worldwide. Bone marrow mesenchymal stem cells (MSCs) participate in the development of a suitable niche for hematopoietic stem cells, and are involved in the development of diseases such as leukemias, to a yet unknown extent. Here we described the effect of secretome of bone marrow MSCs obtained from healthy donors and from patients with acute myeloid leukemia (AML) on leukemic cell lineages, sensitive (K562) or resistant (K562-Lucena) to chemotherapy drugs. Cell proliferation, viability and death were evaluated, together with cell cycle, cytokine production and gene expression of ABC transporters and cyclins. The secretome of healthy MSCs decreased proliferation and viability of both K562 and K562-Lucena cells; moreover, an increase in apoptosis and necrosis rates was observed, together with the activation of caspase 3/7, cell cycle arrest in G0/G1 phase and changes in expression of several ABC proteins and cyclins D1 and D2. These effects were not observed using the secretome of MSCs derived from AML patients. In conclusion, the secretome of healthy MSCs have the capacity to inhibit the development of leukemia cells, at least in the studied conditions. However, MSCs from AML patients seem to have lost this capacity, and could therefore contribute to the development of leukemia.

Hyperbaric oxygen therapy enhances graft healing and mechanical properties after anterior cruciate ligament reconstruction: An experimental study in rabbits.

Hyperbaric oxygen therapy (HBOT) has proven successful in wound healing. However, its potential effects on anterior cruciate ligament (ACL) injuries remain uncertain. This study aimed to investigate the impact of HBOT on graft healing following ACL reconstruction in rabbits. Male New Zealand rabbits underwent ACL reconstruction and were randomly divided into two groups: the HBOT group and the ambient air group. The HBOT group received 100% oxygen at 2.5 atmospheres absolute for 2 h daily for 5 consecutive days, starting from the first day after surgery. The ambient air group was maintained in normal room air throughout the entire period. After 12 weeks following the surgery, animals were euthanized, and their knees were harvested for analysis. The HBOT group demonstrated superior graft maturation and integration in comparison to the ambient air group, as evidenced by lower graft signal intensity on magnetic resonance imaging, decreased femoral and tibial tunnel size, and higher bone mineral density values on high-resolution peripheral quantitative computed tomography scans. Additionally, biomechanical testing indicated that the HBOT group had greater load to failure and stiffness values than the ambient air group. In conclusion, the adjuvant use of HBOT improved ACL graft maturation and integration, reduced tunnel widening, and enhanced the biomechanical properties of the graft. These results may provide important insights into the potential clinical application of HBOT as a therapeutic intervention to enhance graft healing after ACL reconstruction, paving the way for further research in this area.

Muscle function, Lysholm score and hop performance in individuals with clinical indications for the combined reconstruction of the anterior cruciate and the anterolateral ligaments of the knee: A cross-sectional study.

OBJECTIVE: To evaluate hip and knee muscular function, knee patient-reported outcome measures and hop performance in patients with a clinical indication for combined ACL+ALL reconstruction surgery compared to patients with an isolated ACL reconstruction surgery indication (preoperative phase) and to a control group. DESIGN: Cross-sectional study. METHODS: The sample was composed of male individuals, aged between 18 and 59 years, divided into three groups (ACL, ACL+ALL and Control). Isokinetic dynamometry was performed for the flexor and extensor knee muscles and for the hip abductors and adductors. SLHT, COHT and the Lysholm score were performed. Pain, swelling, and thigh trophism were also measured. RESULTS: The study participants were 89 male individuals: 63 in the injury group and 26 in the control group. After applying the criteria for an ALL reconstruction indication, 33 patients were assigned to the ACL Group and 30 patients to the ACL+ALL Group. Regarding knee and hip muscle function, both groups presented worse results when compared to the control group, however, did not show significant differences compared to each other. Regarding the functional variables, the ACL+ALL group showed a significantly shorter distance achieved in the Crossover Hop Test than the other groups, as well as more pain during the tests. CONCLUSION: Knee and hip muscular functions are impaired after an ACL injury and do not seem to be influenced or worsened in individuals with greater rotational instability with clinical indications for combined reconstruction of the anterior cruciate and the anterolateral ligaments of the knee.

Extensor mechanism injury, infection, and an extended time between trauma and surgical approach are related to the need for total knee arthroplasty removal after traumatic dehiscence.

BACKGROUND: Surgical wound-related traumatic complications are rarely reported in the literature. Traumatic dehiscence is unpredictable because of the trauma magnitude and the potential of associated injuries. This study aims to report the clinical outcomes and complications of a case series due to traumatic dehiscence after total knee arthroplasty (TKA) and establish possible criteria for prognosis for maintaining the implant. METHODS: Patients admitted to an emergency room due to traumatic dehiscence after TKA were retrospectively evaluated. Patient data was analyzed and patients who maintained or not the arthroplasty were compared to establish prognosis factors. RESULTS: Thirty-two patients with traumatic dehiscence after TKA were evaluated. The trauma occurred on a mean of 14.3 +/- 25.0 days after the surgical procedure, and debridement in the operating room was performed on a mean of 6.2 +/- 4.9 hours after the trauma. Twenty patients maintained the arthroplasty until the end of follow-up and did not require revision. Factors related to arthroplasty removal were associated extensor mechanism injury (p = 0.026), time from trauma to surgical debridement (p = 0.035), and infection (p = 0.0001) CONCLUSION: Traumatic dehiscence after total knee arthroplasty is an event with a high rate of complications. Extensor mechanism Injury, infection, and extended time between trauma and surgical intervention were poor prognostic factors for arthroplasty maintenance.

Revisiting the role of hyperbaric oxygen therapy in knee injuries: Potential benefits and mechanisms.

Knee injury negatively impacts routine activities and quality of life of millions of people every year. Disruption of tendons, ligaments, and articular cartilage are major causes of knee lesions, leading to social and economic losses. Besides the attempts for an optimal recovery of knee function after surgery, the joint healing process is not always adequate given the nature of intra-articular environment. Based on that, different therapeutic methods attempt to improve healing capacity. Hyperbaric oxygen therapy (HBOT) is an innovative biophysical approach that can be used as an adjuvant treatment post-knee surgery, to potentially prevent chronic disorders that commonly follows knee injuries. Given the well-recognized role of HBOT in improving wound healing, further research is necessary to clarify the benefits of HBOT in damaged musculoskeletal tissues, especially knee disorders. Here, we review important mechanisms of action for HBOT-induced healing including the induction of angiogenesis, modulation of inflammation and extracellular matrix components, and activation of parenchyma cells-key events to restore knee function after injury. This review discusses the basic science of the healing process in knee injuries, the role of oxygen during cicatrization, and shed light on the promising actions of HBOT in treating knee disorders, such as tendon, ligament, and cartilage injuries.

Muscle function, Lysholm score and hop performance in individuals with clinical indications for the combined reconstruction of the anterior cruciate and the anterolateral ligaments of the knee: A cross-sectional study

Abstract Objective To evaluate hip and knee muscular function, knee patient-reported outcome measures and hop performance in patients with a clinical indication for combined ACL+ALL reconstruction surgery compared to patients with an isolated ACL reconstruction surgery indication (preoperative phase) and to a control group. Design Cross-sectional study. Methods The sample was composed of male individuals, aged between 18 and 59 years, divided into three groups (ACL, ACL+ALL and Control). Isokinetic dynamometry was performed for the flexor and extensor knee muscles and for the hip abductors and adductors. SLHT, COHT and the Lysholm score were performed. Pain, swelling, and thigh trophism were also measured. Results The study participants were 89 male individuals: 63 in the injury group and 26 in the control group. After applying the criteria for an ALL reconstruction indication, 33 patients were assigned to the ACL Group and 30 patients to the ACL+ALL Group. Regarding knee and hip muscle function, both groups presented worse results when compared to the control group, however, did not show significant differences compared to each other. Regarding the functional variables, the ACL+ALL group showed a significantly shorter distance achieved in the Crossover Hop Test than the other groups, as well as more pain during the tests. Conclusion Knee and hip muscular functions are impaired after an ACL injury and do not seem to be influenced or worsened in individuals with greater rotational instability with clinical indications for combined reconstruction of the anterior cruciate and the anterolateral ligaments of the knee.

Thromboprophylaxis with unilateral pneumatic device led to less edema and blood loss compared to enoxaparin after knee arthroplasty: randomized trial.

BACKGROUND: Pharmacological and mechanical thromboprophylaxis are frequently used together after total knee arthroplasty (TKA). Most studies in this context compare anticoagulants versus a combination of these drugs with an intermittent pneumatic compression device (IPCD). However, there is uncertainty about the need for the combination of both and whether a unilateral IPCD would alone affect other important clinical outcomes: edema and blood loss. We compared the effects of enoxaparin versus unilateral portable IPCD after TKA on edema and blood loss. We hypothesised that unilateral IPCD would cause the same level of edema and the same blood loss as enoxaparin. METHODS: In this open, randomized trial (1:1), adults with no history of coagulation disorders, anticoagulant use, venous thromboembolism, liver or malignant diseases underwent TKA. For 10 days, participants received the IPCD, used 24 h/day on the operated leg from the end of surgery, or 40 mg of enoxaparin, starting 12 h after surgery. All underwent the same rehabilitation and were encouraged to walk on the same day of surgery. We measured edema (thigh, leg and ankle circumference) before and on the third postoperative day. Blood loss (volume accumulated in the suction drain and drop of hemoglobin and hematocrit in 48 h) was a secondary outcome. RESULTS: We randomized 150 patients and lost 3 to follow-up with enoxaparin and 2 with IPCD. There was no case of symptomatic venous thromboembolism. Four patients needed transfusions (three receiving enoxaparin), one had infection and one hemarthrosis (both in the enoxaparin group). Leg circumference increased by approximately 2 cm for enoxaparin group and 1.5 cm in IPCD (p <  0.001). The increase in ankle circumference was about 1.5 cm in the enoxaparin group (p <  0.001), and almost zero in IPCD (p = 0.447). Enoxaparin group lost 566.1 ml (standard deviation, SD, 174.5) of blood in the first 48 h, versus 420.8 ml (SD 142.5) in the IPCD. CONCLUSIONS: Exclusively mechanical prophylaxis after TKA with portable IPCD only on the operated leg reduces leg and ankle swelling and post-operative blood loss compared to exclusively pharmacological prophylaxis with enoxaparin. Portable devices that can prevent deep vein thrombosis and pulmonary embolism without increasing blood loss or other risks should be further investigated. TRIAL REGISTRATION: REBEC RBR-8k2vpx. Registration date: 06/04/2019.

Preferences and Practices of Brazilian Orthopedists for Thromboprophylaxis Techniques in Total Knee Arthroplasty: Survey Among Members of the Brazilian Society of Knee Surgery (SBCJ).

Objective The present study describes the preferences and current practices of a sample of knee surgeons in Brazil regarding thromboprophylaxis in total knee arthroplasty (TKA). Method In the present internet survey, surgeons from the Brazilian Knee Surgery Society (SBCJ, in the Portuguese acronym) voluntarily answered an anonymous questionnaire including time of personal surgical experience, perceptions about the best thromboprophylaxis options, and actual practices in their work environment. Results From December 2020 to January 2021, 243 participants answered the questionnaire. All, except for 3 (1.2%), reported using thromboprophylaxis, and most (76%) combined pharmacological and mechanical techniques. The most prescribed drug was enoxaparin (87%), which changed to rivaroxaban (65%) after discharge. The time of thromboprophylaxis initiation varied according to the length of training of the knee surgeon ( p ≤ 0.03), and their preferences and practices differed according to the Brazilian region ( p < 0.05) and the health system in which the surgeons work (public or private sector; p = 0.024). The option for mechanical thromboprophylaxis also depended on the training time of the surgeon. Conclusion Thromboprophylaxis preferences and practices in TKA are diverse across Brazilian regions and health systems (public or private sectors). Given the lack of a national clinical guideline, most orthopedists follow either their hospital guidelines or none. The mechanical prophylaxis method and the little use of aspirin are the points that most diverge from international guidelines and practices.

Preferences and Practices of Brazilian Orthopedists for Thromboprophylaxis Techniques in Total Knee Arthroplasty: Survey Among Members of the Brazilian Society of Knee Surgery (SBCJ) / Preferências e práticas de ortopedistas brasileiros por técnicas de tromboprofilaxia na artroplastia total do joelho: Levantamento entre membros da Sociedade Brasileira de Cirurgia do Joelho (SBCJ)

Abstract Objective The present study describes the preferences and current practices of a sample of knee surgeons in Brazil regarding thromboprophylaxis in total knee arthroplasty (TKA). Method In the present internet survey, surgeons from the Brazilian Knee Surgery Society (SBCJ, in the Portuguese acronym) voluntarily answered an anonymous questionnaire including time of personal surgical experience, perceptions about the best thromboprophylaxis options, and actual practices in their work environment. Results From December 2020 to January 2021, 243 participants answered the questionnaire. All, except for 3 (1.2%), reported using thromboprophylaxis, and most (76%) combined pharmacological and mechanical techniques. The most prescribed drug was enoxaparin (87%), which changed to rivaroxaban (65%) after discharge. The time of thromboprophylaxis initiation varied according to the length of training of the knee surgeon (p ≤ 0.03), and their preferences and practices differed according to the Brazilian region (p< 0.05) and the health system in which the surgeons work (public or private sector; p= 0.024). The option for mechanical thromboprophylaxis also depended on the training time of the surgeon. Conclusion Thromboprophylaxis preferences and practices in TKA are diverse across Brazilian regions and health systems (public or private sectors). Given the lack of a national clinical guideline, most orthopedists follow either their hospital guidelines or none. The mechanical prophylaxis method and the little use of aspirin are the points that most diverge from international guidelines and practices.

Resumo Objetivo Descrever as preferências e práticas atuais de uma amostra de cirurgiões de joelho do Brasil quanto à forma de tromboprofilaxia na artroplastia total do joelho (ATJ). Método presente pesquisa realizada pela internet, cirurgiões associados à Sociedade Brasileira de Cirurgia do Joelho (SBCJ) foram convidados a responder voluntariamente a um questionário anônimo incluindo o tempo de experiência cirúrgica pessoal, percepções sobre as melhores opções de tromboprofilaxia e as reais práticas no ambiente onde trabalham. Resultados Entre dezembro de 2020 e janeiro de 2021, 243 participantes responderam ao questionário completo. Exceto por 3 (1,2%) participantes, todos declararam praticar tromboprofilaxia, a maioria (76%) combinando as formas farmacológica e mecânica. A droga mais prescrita é a enoxaparina (87%), com modificação para rivaroxabana (65%) após a alta. O momento de início da tromboprofilaxia variou conforme o tempo de formação do cirurgião de joelho (p ≤ 0,03) e as preferências e práticas variaram conforme a região do país (p< 0,05) e o sistema de saúde no qual trabalham os cirurgiões (público ou privado; p= 0,024). A opção por tromboprofilaxia mecânica também dependeu do tempo de formação do cirurgião. Conclusão As preferências e práticas de tromboprofilaxia na ATJ são diversas nas regiões do Brasil e sistemas de saúde (público ou privado). Dada a inexistência de uma diretriz clínica nacional, a maior parte dos ortopedistas segue ou a diretriz de seu próprio hospital ou nenhuma. O método de profilaxia mecânica e a pouca utilização do ácido acetilsalicílico são os pontos que mais destoam das diretrizes e práticas internacionais.

Quantitative alpha-defensin testing: Is synovial fluid dilution important?

BACKGROUND: Alpha-defensin has been widely studied for the diagnosis of periprosthetic joint infection (PJI). However, there is a lack of detailed information regarding the proper laboratory technique of the enzyme-linked immunosorbent assay (ELISA) method, such as sample dilution. AIM: To assess the influence of dilution in the synovial fluid during ELISA for the diagnosis of knee PJI; and determine which dilution presents a better performance. METHODS: Forty samples of synovial fluid from arthroplasty knees were included, 17 in the infected group and 23 in the aseptic group, according to Musculoskeletal Infection Society criteria. Initially, five synovial fluid samples from each group were assessed for quantitative analysis of alpha-defensin using ELISA. Different dilution ratios (1:10, 1:100, 1:500, 1:1000 and 1:5000) were tested based on the predetermined cutoff value of 5.2 mg/L. The dilutions that performed better were used to compare the results of all samples. RESULTS: For infected cases, a gradual increase in the dilution of synovial fluid samples led to an equivalent increase in alpha-defensin level. The same was not observed in the aseptic cases. Both 1:1000 and 1:5000 dilutions presented satisfactory results to differentiate infected and aseptic cases. Further analyses were performed using 1:1000 and 1:5000 for all 40 samples. The 1:1000 dilution resulted in a sensitivity of 88.2% (95%CI, 66%-98%) and specificity of 95.7% (95%CI, 79%-99%), whereas the 1:5000 dilution presented a sensitivity of 94.1% (95%CI, 73%-99%) and a specificity of 100% (95%CI, 86%-100%). CONCLUSION: The synovial fluid dilution had an important influence on the alpha-defensin ELISA results. Dilutions of 1:5000 showed the best performance for the diagnosis of knee PJI. The results of this study set the basis for a more reliable and reproducible alpha-defensin ELISA during the investigation of PJI, contributing to the expansion of this technique in different treatment centers worldwide.

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 .

Use of small animal PET-CT imaging for in vivo assessment of tendon-to-bone healing: A pilot study.

BACKGROUND: The availability of non-invasive means to evaluate and monitor tendon-bone healing processes in-vivo is limited. Micro Positron-Emission-Tomography (µPET) using 18F-Fluoride is a minimally invasive imaging modality, with which osteoblast activity and bone turnover can be assessed. The aim of this study was to investigate the use of serial in-vivo µPET/CT scans to evaluate bone turnover along the graft-tunnel interface in a rat ACL (anterior cruciate ligament) reconstruction model. METHODS: Unilateral autograft ACL reconstruction was performed in six rats. µPET/CT-scans using 18F-Fluoride were performed 7, 14, 21, and 28 days postoperatively. Standard uptake values (SUV) were calculated for three tunnel regions (intraarticular aperture (IAA), mid-tunnel, and extraarticular aperture (EAA)) of the proximal tibia. Animals were sacrificed at 28 days and evaluated with µCT and histological analysis. RESULTS: SUVs in both bone tunnels showed an increased 18F-Fluoride uptake at 7 days when compared to 14, 21, and 28 days. SUVs showed a gradient on the tibial side, with most bone turnover in the IAA and least in the EAA. At 7, 14, 21, and 28 days, there were significantly higher SUV values in the IAA compared to the EAA (p = .01, < .01, < .01, < .01). SUVs positively correlated with new bone volumetric density obtained with µCT (r = 0.449, p = .013). Volumetric density of newly formed bone detected on µCT correlated with osteoblast numbers observed along the tunnels in histological sections (r = 0.452, p < .016). CONCLUSIONS: Serial in-vivo µPET/CT-scanning has the potential to provide insight into bone turnover and therefore osteoblastic activity during the healing process. As a result, it allows us to directly measure the effect of interventional strategies in tendon-bone healing.

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 .

Performance of alpha-defensin lateral flow test after synovial fluid centrifugation for diagnosis of periprosthetic knee infection.

BACKGROUND: The quantitative alpha-defensin enzyme-linked immunosorbent assay (ELISA) demands a prior synovial fluid centrifugation, whereas this processing is not routinely required prior to the alpha-defensin lateral flow test. AIM: To evaluate whether a prior synovial fluid centrifugation could lead the lateral flow performance to achieve comparable results to ELISA during periprosthetic joint infection (PJI) diagnosis. METHODS: Fifty-three cases were included in this study: 22 classified as PJI and 31 classified as aseptic cases, according to Musculoskeletal Infection Society 2013 criteria. Synovial fluid samples were submitted to centrifugation, and the supernatant was evaluated by ELISA and lateral flow tests. The sensitivity (SE), specificity (SP) and accuracy of each method were calculated as well as the agreement between those two methods. RESULTS: In all of the 31 samples from aseptic patients, alpha-defensin ELISA and lateral flow tests showed negative results for infection. Regarding the 22 infected patients, the lateral flow test was positive in 19 cases (86.4%) and the ELISA was positive in 21 (95.5%). Sensibility, SP and accuracy were, respectively, 86.4% (95%CI: 65.1%-97.1%), 100% (95%CI: 88.8%-100%) and 93.2% (95%CI: 82.8%-98.3%) for the lateral flow test and 95.5% (95%CI: 77.2%-99.9%), 100% (95%CI: 88.8%-100%) and 98.1% (95%CI: 89.9%-100%) for ELISA. An agreement of 96.2% between those methods were observed. No statistical difference was found between them (P = 0.48). CONCLUSION: Alpha-defensin lateral flow test showed high SE, SP and accuracy after a prior synovial fluid centrifugation, achieving comparable results to ELISA. Considering the lower complexity of the lateral flow and its equivalent performance obtained in this condition, a prior centrifugation might be added as a valuable step to enhance the PJI diagnosis.

Lever sign test for chronic acl injury: a comparison with lachman and anterior drawer tests / Teste da alavanca para lesão crônica do lca: comparação com os testes de lachman e gaveta anterior

ABSTRACT Objective: This study aims to evaluate the sensitivity and specificity of the lever sign test in patients with and without chronic Anterior Cruciate Ligament (ACL) injuries in an outpatient setting and the inter-examiner agreement of surgeons with different levels of experience. Methods: 72 consecutive patients with a history of previous knee sprains were included. The Lachman, anterior drawer, and Lever Sign tests were performed for all subjects in a randomized order by three blinded raters with different levels of experience. Sensitivity, specificity, positive predictive value, negative predictive value, and inter-rater agreement were estimated for all tests. Results: Among the 72 patients, the prevalence of ACL injuries was 54%. The lever test showed sensitivity of 64.1% (95% CI 0.47-0.78) and specificity of 100% (95% CI 0.87-1.00) for the senior examiner. For the less experienced examiner the sensitivity was 51.8% and the specificity was 93.7%. Positive predictive values (PPV) and negative predictive values (NPV) were 100% and 70.2%, respectively. Conclusion: Lever Sign test shows to be a maneuver of easy execution, with 100% specificity and 100% PPV. Moderate agreement between experienced examiners and low agreement among experienced and inexperienced examiners was found. This test may play a role as an auxiliary maneuver. Level of Evidence I, Diagnostic Studies - Investigating a Diagnostic Test.

RESUMO Objetivo: O objetivo deste estudo foi avaliar a sensibilidade e a especificidade do teste da alavanca em pacientes ambulatoriais com e sem lesões crônicas do LCA e a concordância entre examinadores com diferentes níveis de experiência. Métodos: Setenta e dois pacientes consecutivos com histórico de entorse de joelho foram incluídos. O teste de lachman, gaveta anterior e teste de alavanca foram realizados para todos os indivíduos em ordem randomizada por 3 examinadores cegados com diferentes níveis de experiência. Sensibilidade, especificidade, valor preditivo positivo, valor preditivo negativo e concordância interavaliadores foram calculados para todos os testes. Resultados: Entre os 72 pacientes, a prevalência de lesões do LCA foi de 54%. O teste da alavanca mostrou sensibilidade de 64,1% (IC95% 0,47-0,78) e especificidade de 100% (IC95% 0,87-1,00) para o examinador sênior. Para o examinador menos experiente, a sensibilidade foi de 51,8% e a especificidade, de 93,7%. Valores preditivos positivos (VPP) e valores preditivos negativos (VPN) foram de 100% e 70,2%, respectivamente. Conclusão: O teste da alavanca mostra ser uma manobra de fácil execução, com 100% de especificidade e 100% de PPV. Foi encontrada concordância moderada entre examinadores experientes e baixa concordância entre examinadores experientes e inexperientes. Este teste pode desempenhar um papel como uma manobra adjuvante. Nível de Evidência I, Estudos Diagnósticos - Investigação de um Exame para Diagnóstico.

LEVER SIGN TEST FOR CHRONIC ACL INJURY: A COMPARISON WITH LACHMAN AND ANTERIOR DRAWER TESTS.

OBJECTIVE: This study aims to evaluate the sensitivity and specificity of the lever sign test in patients with and without chronic Anterior Cruciate Ligament (ACL) injuries in an outpatient setting and the inter-examiner agreement of surgeons with different levels of experience. METHODS: 72 consecutive patients with a history of previous knee sprains were included. The Lachman, anterior drawer, and Lever Sign tests were performed for all subjects in a randomized order by three blinded raters with different levels of experience. Sensitivity, specificity, positive predictive value, negative predictive value, and inter-rater agreement were estimated for all tests. RESULTS: Among the 72 patients, the prevalence of ACL injuries was 54%. The lever test showed sensitivity of 64.1% (95% CI 0.47-0.78) and specificity of 100% (95% CI 0.87-1.00) for the senior examiner. For the less experienced examiner the sensitivity was 51.8% and the specificity was 93.7%. Positive predictive values (PPV) and negative predictive values (NPV) were 100% and 70.2%, respectively. CONCLUSION: Lever Sign test shows to be a maneuver of easy execution, with 100% specificity and 100% PPV. Moderate agreement between experienced examiners and low agreement among experienced and inexperienced examiners was found. This test may play a role as an auxiliary maneuver. Level of Evidence I, Diagnostic Studies - Investigating a Diagnostic Test.

OBJETIVO: O objetivo deste estudo foi avaliar a sensibilidade e a especificidade do teste da alavanca em pacientes ambulatoriais com e sem lesões crônicas do LCA e a concordância entre examinadores com diferentes níveis de experiência. MÉTODOS: Setenta e dois pacientes consecutivos com histórico de entorse de joelho foram incluídos. O teste de lachman, gaveta anterior e teste de alavanca foram realizados para todos os indivíduos em ordem randomizada por 3 examinadores cegados com diferentes níveis de experiência. Sensibilidade, especificidade, valor preditivo positivo, valor preditivo negativo e concordância interavaliadores foram calculados para todos os testes. RESULTADOS: Entre os 72 pacientes, a prevalência de lesões do LCA foi de 54%. O teste da alavanca mostrou sensibilidade de 64,1% (IC95% 0,47-0,78) e especificidade de 100% (IC95% 0,87-1,00) para o examinador sênior. Para o examinador menos experiente, a sensibilidade foi de 51,8% e a especificidade, de 93,7%. Valores preditivos positivos (VPP) e valores preditivos negativos (VPN) foram de 100% e 70,2%, respectivamente. CONCLUSÃO: O teste da alavanca mostra ser uma manobra de fácil execução, com 100% de especificidade e 100% de PPV. Foi encontrada concordância moderada entre examinadores experientes e baixa concordância entre examinadores experientes e inexperientes. Este teste pode desempenhar um papel como uma manobra adjuvante. Nível de Evidência I, Estudos Diagnósticos - Investigação de um Exame para Diagnóstico.

Comparative CT with stress manoeuvres for diagnosing distal isolated tibiofibular syndesmotic injury in acute ankle sprain: a protocol for an accuracy- test prospective study.

INTRODUCTION: Although several imaging options are available for diagnosing syndesmotic injury, a fundamental question that guides treatment remains unanswered. Syndesmotic instability is still challenging to diagnose correctly, and syndesmotic disruption and true syndesmotic instability should be differentiated. Currently, imaging tests quickly diagnose severe syndesmotic instability but have difficulty in diagnosing mild and moderate cases. This study aims to investigate which strategy among an existing CT index test and two new add-on CT index tests with stress manoeuvres more accurately diagnoses syndesmotic instability. The secondary objective is to investigate the participants' disability outcomes by applying the Foot and Ankle Ability Measure questionnaire. METHODS AND ANALYSES: This study of a diagnostic accuracy test will consecutively select individuals older than 18 years with a clinical diagnosis of a suspected acute syndesmotic injury. Three strategies of the CT index test (one in the neutral position and two with stress) will examine the accuracy using MRI as the reference standard. The external rotation and dorsiflexion of the ankle will guide the stress manoeuvres. A comparison of measurements between the injured syndesmosis and the uninjured contralateral side of the same individual will investigate the syndesmotic instability, by evaluating the rotational and translational relationships between the fibula and tibia. Sensitivity, specificity, area under the receiver operating characteristic curve and likelihood analyses will compare the diagnostic accuracies of the strategies. ETHICS AND DISSEMINATION: The Internal Review Board and the Einstein Ethics Committee approved this study (registered number 62100016.5.0000.0071). All participants will receive an oral description of the study's aim, and the choice to participate will be free and voluntary. Participants will be enrolled after they sign the written informed consent form, including the terms of confidentiality. The results will be presented at national and international conferences and published in peer-reviewed journals and social media. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registry (NCT04095598; preresults).

The use of negative-pressure wound therapy after total knee arthroplasty is effective for reducing complications and the need for reintervention.

BACKGROUND: Wound healing complications are causal factors of prosthesis infection and poor postoperative evolution of patients after total knee arthroplasty (TKA). Negative-pressure wound therapy (NPWT) can be an option to minimize these complications. The aim of this study is to compare the complications of patients undergoing TKA who used a portable NPWT device in the immediate postoperative period with those of a control group. METHODS: A total of 296 patients were evaluated. Patients were divided into two groups: those who used NPWT for seven days in the postoperative period (Group 1 - prospective evaluated) and those who used conventional dressings (Group 2 - historical control group). Epidemiological data, comorbidities, local parameters related to the surgical wound and complications were evaluated. RESULTS: The groups did not differ in regard to sex, age and clinical comorbidities. Overall, 153 (51.7%) patients had at least one risk factor for wound complications. Patients who used NPWT had a lower rate of complications (28.5% vs. 45.7%, p = 0.001) and a lower rate of reintervention in the operating room (2% vs. 8.5%, p = 0.001). Patients in group 1 had a lower incidence of hyperaemia (14.7% vs. 40.2%, p = 0.01), skin necrosis (2.1% vs. 8.5%, p = 0.04) and wound dehiscence (3.1% vs 10.1%, p = 0.03). The use of NPWT was a protective factor for the presence of complications, with an odds ratio of 0.36 (95% CI 0.206-0.629). CONCLUSION: The number of complications related to the wound after TKA is high; however, most of them are minor and have no impact on the treatment and clinical evolution of patients. The use of NPWT decreased the number of surgical wound complications, especially hyperaemia, dehiscence and necrosis, and reduced the need for reintervention.