The effects of drainage tube on pain and functional recovery after unicompartmental knee arthroplasty / Efeitos do tubo de drenagem na dor e recuperação funcional após artroplastia unicompartimental do joelho

ABSTRACT Objective: The objective of this study was to evaluate the impact of drainage tube placement on postoperative pain, recovery, and opioid consumption within a 72-hour period following unicompartmental knee arthroplasty (UKA). Methods: Patients with medial knee osteoarthritis who underwent UKA from January 2019 to August 2020 were enrolled in the study and divided into two groups based on whether they received a drain postoperatively. Results: The drainage group had significantly lower VAS scores on day 1, day 2, and day 3, in addition to significantly smaller changes in the circumference of the knee joint within 3 days postoperatively (P <0.05). The ROM in the drainage group significantly increased at 3 days and 1 month post-surgery, with a statistically significant difference in morphine consumption between the two groups at 3 days (P<0.05). The incidence of postoperative nausea and vomiting (5 cases) and wound bleeding (1 case) was lower in the drainage group compared to the non-drainage group (P<0.05). Conclusions: The placement of a drainage tube in UKA may reduce the swelling of knee joint and pain, which not only reduces the use of Opioid but also facilitates early functional activities of the knee joint. Level of Evidence III; Retrospective Comparative Study.

RESUMO Objetivo: O objetivo deste estudo foi avaliar o impacto da implantação do tubo de drenagem na dor pós-operatória, na recuperação e no consumo de opioides em um período de 72 horas após a artroplastia unicompartimental do joelho (UKA). Métodos: Pacientes com osteoartrite medial do joelho submetidos à UKA de janeiro de 2019 a agosto de 2020 foram incluídos no estudo e divididos em dois grupos com base no fato de terem ou não recebido um dreno no pós-operatório. Resultados: O grupo de drenagem apresentou escores EVA significativamente menores no dia 1, no dia 2 e no dia 3, além de alterações significativamente menores na circunferência da articulação do joelho em 3 dias de pós-operatório (P <0,05). A ADM no grupo de drenagem aumentou significativamente em 3 dias e 1 mês após a cirurgia, com uma diferença estatisticamente significativa no consumo de morfina entre os dois grupos em 3 dias (P<0,05). A incidência de náuseas e vômitos no pós-operatório(5 casos) e sangramento da ferida (1 caso) foi menor no grupo de drenagem em comparação com o grupo sem drenagem (P<0,05). Conclusão: A utilização de tubo de drenagem na UKA pode reduzir o edema articular do joelho e a dor, reduzindo o uso de opioides e facilitando as atividades funcionais iniciais da articulação do joelho. Nível de Evidência III; Estudo Comparativo Retrospectivo.

Knee osteoarthritis and aging: evaluation of the different muscles of thigh / Artrosis de rodilla y envejecimiento: investigación de los diferentes músculos del muslo / Osteoartrite de joelho e envelhecimento: investigação de diferentes músculos da coxa

ABSTRACT Introduction: Osteoarthritis (OA) is a chronic inflammatory degenerative disease, characterized by progressive degeneration of the articular cartilage, affecting mostly the knee joint. The elderly population is the most affected, intensifying the aging process. The concentration of intramuscular adipose tissue in the thigh muscles and knee OA at different ages remains under investigation. Objective: Investigate the cross-sectional area of thigh muscles at different ages with the relationship of the presence of intramuscular fat and knee OA. Methods: 80 participants were paired into 4 groups: Young Osteoarthritis Group and Old Osteoarthritis Group, both sedentary with knee OA diagnosis II or III; Healthy Young Group and Healthy Old Group, both healthy and sedentary. The groups were paired according to gender and body mass index, submitted to physiotherapeutic evaluation, WOMAC questionnaire, knee X-ray and thigh CT scans. Morphometric analysis was performed manually with ITK-SNAP software (version 3.6), by a single evaluator. Statistical analysis used the one-way ANOVA test followed by Bonferroni post-hoc for dependent variables (p≤0.05). Results: Comparison of the cross-sectional area of the rectus femoris, vastus lateralis, semitendinosus, sartorius and gracilis muscles between the groups indicated no significant differences (p>0.05). The study of attenuation for muscle adipose tissue indicated no significant difference in the values of between the OA-Young and Aged-S groups for all the muscles evaluated. Conclusion: Young individuals with knee OA present muscle morphological characteristics similar to those found during the aging process, characterizing early aging of the thigh muscles. Level of Evidence III; Retrospective cross-sectional and observational study.

RESUMEN Introducción: La artrosis (OA) es una enfermedad inflamatoria degenerativa crónica, caracterizada por la degeneración progresiva del cartílago articular, que afecta principalmente a la articulación de la rodilla. La población anciana es la más afectada, intensificándose el proceso de envejecimiento. La concentración de tejido adiposo intramuscular en los músculos del muslo y la OA de rodilla a diferentes edades sigue siendo objeto de investigación. Objetivo: Investigar el área transversal de los músculos del muslo a diferentes edades con la relación de la presencia de grasa intramuscular y la OA de rodilla. Métodos: Se emparejó a 80 participantes en 4 grupos: Grupo de jóvenes con osteoartritis y Grupo de mayores con osteoartritis, ambos sedentarios y con diagnóstico de OA de rodilla II o III; Grupo de jóvenes sanos y Grupo de mayores sanos, ambos sanos y sedentarios. Los grupos fueron emparejados según sexo e índice de masa corporal, sometidos a evaluación fisioterapéutica, cuestionario WOMAC, exámenes radiográficos de las rodillas y tomografía computarizada del muslo. El análisis morfométrico se realizó manualmente con el software ITK-SNAP (versión 3.6), por un único evaluador. En el análisis estadístico se utilizó la prueba ANOVA unidireccional seguida del post-hoc de Bonferroni para las variables dependientes (p≤0,05). Resultados: La comparación del área transversal de los músculos recto femoral, vasto lateral, semitendinoso, sartorio y gracilis entre los grupos no indicó diferencias significativas (p>0,05). El estudio de la atenuación para el tejido adiposo muscular no indicó diferencias significativas en los valores de entre los grupos OA-Young y Aged-S para todos los músculos evaluados. Conclusión: Individuos jóvenes con OA de rodilla presentan características morfológicas musculares similares a las encontradas durante el proceso de envejecimiento, caracterizando el envejecimiento precoz de los músculos del muslo. Nivel de Evidencia III; Estudio transversal y observacional retrospectivo.

RESUMO Introdução: A osteoartrite (OA) é uma doença inflamatória crônico-degenerativa, caracterizada pela degeneração progressiva da cartilagem articular, acometendo em maior parte a articulação do joelho. A população idosa é a mais atingida, intensificando o processo de envelhecimento. A concentração de tecido adiposo intramuscular nos músculos da coxa e a OA de joelho em diferentes idades permanece em investigação. Objetivo: Investigar a área de secção transversa dos músculos da coxa em diferentes idades com a relação da presença de gordura intramuscular e OA de joelho. Métodos: 80 participantes foram pareados em 4 grupos: Grupo Osteoartrite Jovem e Grupo Osteoartrite Idoso, ambos sedentários com diagnóstico de OA de joelho II ou III; Grupo Jovem Saudável e Grupo Idoso Saudável, ambos saudáveis e sedentários. Os grupos foram pareados de acordo com sexo e índice de massa corporal, submetidos à avaliação fisioterapêutica, questionário WOMAC, exames de raio-x dos joelhos e tomografia computadorizada da coxa. A análise morfométrica foi realizada manualmente com software ITK-SNAP (versão 3.6), por um único avaliador. Análise estatística utilizou o teste ANOVA one-way seguido pelo post-hoc de Bonferroni, para variáveis dependentes (p≤0,05). Resultados: A comparação da área de secção transversa dos músculos reto femoral, vasto lateral, semitendinoso, sartório e grácil, entre os grupos, não indicou diferenças significativas (p>0,05). O estudo da atenuação para o tecido adiposo muscular não indicou diferença significativa nos valores de entre os grupos OA-Jovem e Idoso-S para todos os músculos avaliados. Conclusão: Indivíduos jovens com OA de joelho apresentam características morfológicas musculares semelhantes às encontradas durante o processo de envelhecimento, caracterizando um envelhecimento precoce dos músculos da coxa.Nível de Evidência III; Estudo retrospectivo transversal e observacional.

Medial condyle hypoplasia in adolescent and young adult patients with trochlear dysplasia: a retrospective study / Hipoplasia do côndilo medial em pacientes adolescentes e adultos jovens com displasia troclear: estudo retrospectivo

Abstract Objective: To determine the association between medial femoral condyle hypoplasia and trochlear dysplasia by analyzing the knee magnetic resonance imaging scans of young patients with or without trochlear dysplasia. Materials and Methods: This was a retrospective analysis of magnetic resonance imaging scans of the knees of young individuals (16-35 years of age): 30 patients with trochlear dysplasia and 30 individuals with no signs of patellofemoral instability. The ratios between the depth, width, and height of the medial and lateral femoral condyles (dLC/dMC, wLC/wMC, and hLC/hMC, respectively) were calculated, as was the ratio between the width of the medial condyle and the total width of the femur (wMC/FW). All of the values were determined in consensus by two radiologists. Results: We evaluated 60 patients: 30 with trochlear dysplasia and 30 without. The mean dLC/dMC, wLC/wMC, and hLC/hMC ratios were higher in the patients than in the controls (p < 0.05), whereas the mean wMC/FW ratio was lower in the patients (p < 0.05). The optimal cutoff values, obtained by calculating the areas under the receiver operating characteristic curves, were 1.0465 for the dLC/dMC ratio (76% sensitivity and 63.3% specificity), 0.958 for the wLC/wMC ratio (80% sensitivity and 73.3% specificity), and 1.080 for the hLC/hMC ratio (93.3% sensitivity and 93.3% specificity). Conclusion: Our findings confirm our hypothesis that trochlear dysplasia is associated with medial condyle hypoplasia.

Resumo Objetivo: Determinar a associação entre hipoplasia do côndilo femoral medial e displasia troclear mediante análise de ressonância magnética do joelho de pacientes jovens com displasia troclear e sem displasia troclear. Materiais e Métodos: Análise retrospectiva de exames de ressonância magnética de joelhos de indivíduos jovens (16 a 35 anos de idade), sendo 30 pacientes com displasia troclear e 30 indivíduos sem sinais de instabilidade femoropatelar. As razões entre a profundidade, largura e altura dos côndilos femorais mediais e laterais (dLC/dMC, wLC/wMC e hLC/hMC, respectivamente) foram calculadas, assim como a razão entre a largura do côndilo medial e a largura total do fêmur (wMC/FW). Todos os valores foram determinados em consenso por dois radiologistas Resultados: Foram incluídos no estudo 60 adolescentes e adultos jovens, 30 com displasia troclear e 30 sem displasia troclear. A média das razões dLC/dMC, wLC/wMC, hLC/hMC foi maior nos pacientes do que nos controles (p < 0,05), enquanto a média da razão wMC/FW foi menor nos pacientes (p < 0,05). Os valores de corte ótimos obtidos da área sob a curva característica de operação do receptor foram 1,0465 para dLC/dMC (sensibilidade de 76% e especificidade de 63,3%), 0,958 para wLC/wMC (sensibilidade de 80% e especificidade de 73,3%) e 1,080 para hLC/hMC (sensibilidade de 93,3% e especificidade de 93,3%). Conclusão: Nossos resultados confirmam nossa hipótese de que a displasia troclear está associada a hipoplasia do côndilo medial.

Assessment of the relationship between smoking and meniscal injury / Avaliação da relação entre tabagismo e lesão meniscal

Abstract Objective: To determine whether being a smoker and the years of smoking correlate with the presence and degree of meniscal injury. Materials and Methods: Individuals who underwent magnetic resonance imaging of the knee were divided into two groups: smokers and nonsmokers. For each smoker, the total smoking history was calculated by multiplying the daily consumption (packs/day) by the years of smoking, and the result is expressed as pack-years. In the evaluation of meniscal injury, the grade of injury was recorded. The thickness of the subcutaneous adipose tissue, as an indicator of obesity, was measured at the medial knee on axial plane images. The relationships that smoking and obesity had with meniscal injury were analyzed statistically. Results: A total of 156 individuals were included in the study. The smoker group consisted of 48 individuals (30.8%), and the nonsmoker group consisted of 108 (69.2%). The meniscus was normal in one (2.1%) of the smokers and in 32 (29.6%) of the nonsmokers (p < 0.0001). The median subcutaneous adipose tissue thickness was 23 mm and 24 mm in the smokers and nonsmokers, respectively (p = 0.900). A moderate but statistically significant correlation was observed between packs/day and injury grade, as well as between pack-years and injury grade (r = 0.462, p = 0.001 and r = 0.523, p = 0.001, respectively). Smoking and age significantly increased the risk of meniscal injury, by 31.221 times (p = 0.001) and 1.076 times (p < 0.001), respectively. Conclusion: Our findings indicate that current smoking and smoking history correlate significantly with meniscal injury grade.

Resumo Objetivo: Determinar a correlação do tabagismo e do tempo de tabagismo com a presença e o grau de lesão do menisco. Materiais e Métodos: Foram incluídos pacientes submetidos a ressonância magnética do joelho e divididos em dois grupos: fumantes e não fumantes. O consumo total de cigarros dos pacientes foi calculado multiplicando-se a quantidade diária de cigarros (maços/dia) pelo tempo de tabagismo (anos). O grau mais alto de lesão foi registrado na avaliação da lesão meniscal. A espessura do tecido adiposo subcutâneo foi medida com base em imagem do joelho em plano axial, como indicador de obesidade. A relação entre tabagismo, obesidade e lesão meniscal foi analisada estatisticamente. Resultados: Foram incluídos no estudo 156 indivíduos. O grupo de fumantes consistiu de 48 (30,8%) indivíduos e o grupo de não fumantes, de 108 (69,2%) indivíduos. O menisco estava normal em um (2,1%) fumante e em 32 (29,6%) não fumantes (p < 0,0001). A espessura média do tecido adiposo subcutâneo em fumantes foi 23 mm e nos não fumantes foi 24 mm, com valor de p = 0,900. Foi observada correlação moderada e estatisticamente significante entre o grau de lesão por pacote/dia (r = 0,462, p = 0,001) e o grau de lesão por pacote × ano (r = 0,523, p = 0,001). O tabagismo e a idade afetaram significativamente o risco de lesão do menisco (31,221 vezes, p = 0,001 e 1,076 vez, p < 0,001, respectivamente). Conclusão: Foi encontrada correlação significativa entre tabagismo/dia e grau de lesão do menisco e pacote de tabagismo × ano e grau de lesão do menisco.

Risk Factors for Symptomatic Cyclops Lesion Formation after Anterior Cruciate Ligament Reconstruction / Fatores de risco para formação de lesão cyclops sintomática após a reconstrução do ligamento cruzado anterior

Abstract Objective To evaluate the incidence of symptomatic cyclops lesions requiring surgical treatment after anterior cruciate ligament (ACL) reconstruction and to establish possible intraoperative risk factors related to it. Methods Three hundred and eighty-nine patients aged between 18 and 50 years who underwent primary ACL reconstruction were retrospectively evaluated. Patients were divided into groups according to the presence or absence of symptomatic cyclops lesions, and their characteristics were compared. Patients with associated lesions that required additional surgical procedures (except anterolateral extra-articular procedures) were not included. The rate of symptomatic cyclops lesions was recorded and the following parameters were evaluated: age, gender, time from injury to surgery, graft type and diameter, femoral tunnel perforation technique, fixation type, presence of knee hyperextension, preservation of the ACL remnant, associated anterolateral extra-articular procedure, associated meniscal injury and participation in sports. Results 389 patients were evaluated and 26 (6.7%) patients developed cyclops. The patients with and without cyclops lesions did not differ in age, time from injury to surgery, graft type or diameter, surgical technique, femoral fixation method, presence of knee hyperextension, remnant preservation and associated meniscal injury. The group with cyclops lesion had a higher proportion of females (10 (38.4%) vs 68 (18.7%); OR = 2.7; p= 0.015), higher proportion of extra-articular reconstruction (18 (11.8%) vs 8 (3.4%); OR = 3.8; p= 0.001) and higher proportion of sports practice (23 (8.6%) vs 3 (2.5%); OR = 3.6; p= 0.026). Conclusion In our series, 6.7% of the patients required arthroscopic removal of cyclops lesions. Female gender, associated extra-articular reconstruction and sports practice were factors related to this lesion. Remnant preservation had no relationship with cyclops lesion formation.

Resumo Objetivo Avaliar a incidência de lesões cyclops sintomáticas que precisam de tratamento cirúrgico após a reconstrução do ligamento cruzado anterior (LCA) e estabelecer os possíveis fatores de risco intraoperatórios relacionados a elas. Métodos Trezentos e oitenta e nove pacientes com idades entre 18 e 50 anos submetidos à reconstrução primária do LCA foram avaliados de forma retrospectiva. Os pacientes foram divididos em grupos de acordo com a presença ou ausência de lesões cyclops sintomáticas e suas características foram comparadas. Não foram incluídos pacientes com lesões associadas que necessitassem de outros procedimentos cirúrgicos (à exceção de procedimentos extra-articulares ântero-laterais). A taxa de lesões cyclops sintomáticas foi registrada e os seguintes parâmetros foram avaliados: idade, sexo, tempo da lesão à cirurgia, tipo e diâmetro do enxerto, técnica de perfuração do túnel femoral, tipo de fixação, presença de hiperextensão do joelho, preservação do LCA remanescente, associação a procedimento extra-articular ântero-lateral, lesão de menisco associada e participação em esportes. Resultados Dos 389 pacientes avaliados, 26 (6,7%) desenvolveram lesão cyclops. Os pacientes com e sem lesão cyclops não diferiram quanto à idade, tempo da lesão à cirurgia, tipo ou diâmetro do enxerto, técnica cirúrgica, método de fixação femoral, presença de hiperextensão do joelho, preservação do LCA remanescente e lesão de menisco associada. O grupo com lesão cyclops apresentou mais mulheres (10 [38,4%] vs. 68 [18,7%]; razão de probabilidades [OR] = 2,7; p= 0,015), maior proporção de reconstrução extra-articular (18 [11,8%] vs. 8 [3,4 %]; OR = 3,8; p= 0,001) e maior proporção de prática esportiva (23 [8,6%] vs. 3 [2,5%]; OR = 3,6; p= 0,026). Conclusão Em nossa série, 6,7% dos pacientes necessitaram de remoção artroscópica das lesões cyclops. O sexo feminino, a reconstrução extra-articular associada e a prática esportiva foram fatores relacionados a essa lesão. A preservação do menisco remanescente não foi associada à formação de lesões cyclops.

An Unusual Cause of Posterior Knee Pain: Mucoid Degeneration of the Anterior Cruciate Ligament - Case Report / Uma causa incomum de dor posterior no joelho: degeneração mucóide do ligamento cruzado anterior - Relato de caso

Abstract Mucoid degeneration of the anterior cruciate ligament (ACL) is an uncommon cause of pain in the posterior region of the knee, of unknown pathophysiology and underdiagnosed. The best treatment modality is still under discussion. Resection of the lesion with partial ACL debridement has shown good results without the occurrence of instability. The authors present a case of mucoid degeneration of the ACL treated with resection of the mucoid degeneration and partial debridement of the ACL by arthroscopy.

Resumo A degeneração mucoide do ligamento cruzado anterior (LCA) é uma causa pouco frequente de dor na região posterior do joelho, de patofisiologia desconhecida e subdiagnosticada. A melhor modalidade de tratamento ainda está em discussão. A ressecção da lesão com desbridamento parcial do LCA tem apresentado bons resultados, sem a ocorrência de instabilidade. Os autores apresentam um caso de degeneração mucoide do LCA tratado com ressecção da degeneração mucoide e desbridamento parcial do LCA por artroscopia.

Where is tibial edema located in cases of osteomeniscal impingement? / Onde está o edema ósseo tibial em casos de impacto osteomeniscal?

Abstract Objective: To characterize the location of tibial edema related to meniscal degeneration with a flap displaced into the meniscotibial recess (osteomeniscal impingement) on magnetic resonance imaging (MRI). Materials and Methods: We evaluated 40 MRI examinations of patients submitted to surgery due to inferior displacement of a meniscal flap tear into the meniscotibial recess and peripheral bone edema. Tibial edema was quantified in the coronal and axial planes. Results: On coronal MRI sequences, edema started in the tibial periphery and extended for a mean of 5.6 ± 1.4 mm, or 7.4 ± 2.1% of the tibial plateau. In the craniocaudal direction, the mean extension was 8.8 ± 2.9 mm. The mean ratio between the extent of craniocaudal and mediolateral edema was 1.6 ± 0.6. In the axial plane, the edema started in the medial periphery and extended for a mean of 6.2 ± 2.0 mm, or 8.2 ± 2.9% of the tibial plateau. In the anteroposterior measurement, the mean start and end of the edema was 21.4 ± 5.4 mm and 35.7 ± 5.7 mm, respectively, or 43.4 ± 10.2% and 72.8 ± 11.1% of the tibial plateau. Conclusion: Apparently, tibial edema resulting from osteomeniscal impingement always starts in the periphery of the meniscus. In the coronal plane, it appears to be more extensive in the craniocaudal direction than in the mediolateral direction. In the axial plane, we found it to extend, on average, approximately 6.2 mm in the mediolateral direction and to be most commonly located from the center to the posterior region of the medial tibial plateau.

Resumo Objetivo: Caracterizar a localização do edema ósseo tibial relacionado a lesão meniscal degenerativa com fragmento deslocado no recesso meniscotibial (impacto osteomeniscal) por meio de ressonância magnética (RM). Materiais e Métodos: Quarenta RMs de pacientes submetidos a cirurgia por fragmento deslocado do menisco medial no recesso meniscotibial e edema ósseo periférico foram avaliadas. Edema ósseo tibial foi quantificado nos planos coronal e axial. Resultados: No plano coronal, o edema iniciou-se na periferia tibial e estendeu-se por 5,6 ± 1,4 mm, ou 7,4 ± 2,1% do platô. Na direção craniocaudal, o edema estendeu-se em média 8,8 ± 2,9 mm. A média entre a extensão do edema craniocaudal e mediolateral foi 1,6 ± 0,6. No plano axial, o edema iniciou-se na periferia medial e estendeu-se por 6,2 ± 2,0 mm, ou 8,2 ± 2,9% da medida da tíbia. Na medida anteroposterior, o edema iniciou-se em 21,4 ± 5,4 mm e terminou em 35,7 ± 5,7 mm ou iniciou-se em 43,4 ± 10,2% e terminou em 72,8 ± 11,1% do platô tibial. Conclusão: O edema ósseo tibial relacionado aos casos de impacto osteomeniscal sempre se inicia na periferia do menisco. Ele é mais extenso na direção craniocaudal do que mediolateral no plano coronal. No plano axial, ele estende-se por 6,2 mm de medial a lateral e é mais frequentemente localizado no centro da região posterior do platô medial.

Calculation of the Minimal Important Clinical Difference of the Lysholm and IKDC Scores After Anterior Cruciate Ligament Reconstruction / Cálculo da mínima diferença clínica importante dos escores Lysholm e IKDC após reconstrução do ligamento cruzado anterior

Abstract Objective To calculate the minimal important clinical difference (MICD) value for the Lysholm and International Knee Documentation Committee (IKDC) scores in a sample of patients submitted to anterior cruciate ligament reconstruction. Methods Primary, observational, retrospective, analytical study of participants submitted to anterior cruciate ligament reconstruction from March 2019 to December 2020 by the same surgeon, with a minimum follow-up of 6 months, analysis of knee function in the pre- and postoperative period by the Lysholm and IKDC scores, and answer to an anchor question at 6 months postoperatively for the calculation of the MICD of each score. Results A total of 59 patients participated in the study, with a mean age of 27.1 ± 5.7 years old. In the comparison between pre- and postoperative scores of all groups, there was an increase in values with statistical significance after intervention. The MICD was 5.5 for the Lysholm score, and the MICD value for the IKDC score could not be determined. Conclusion For the Lysholm score, the calculation of the MICD value by the anchor question method in the sample evaluated was 5.5. It was not possible to determine the value of the MICD for the IKDC score.

Resumo Objetivo Calcular o valor da mínima diferença clinicamente importante (MDCI) para os escores de Lysholm e International Knee Documentation Commitee (IKDC) na amostra de pacientes submetidos a reconstrução de ligamento cruzado anterior. Métodos Estudo primário, observacional, retrospectivo, analítico, de participantes submetidos a reconstrução do ligamento cruzado anterior no período de março de 2019 a dezembro de 2020, pelo mesmo cirurgião, com seguimento mínimo de 6 meses, análise da função do joelho no período pré e pós-operatório pelos escores de Lysholm e IKDC, e resposta a uma pergunta âncora aos 6 meses de seguimento pós-operatório, para o MDCI de cada escore. Resultados Participaram do estudo 59 pacientes, com média de idade de 27,1 ± 5,7 anos. Na comparação dos escores pré- e pós-operatórios de todos os grupos, observa-se aumento dos valores com significância estatística após a intervenção. A MDCI foi de 5,5 para o escore de Lysholm, não tendo sido possível determinar o valor para o IKDC. Conclusão O cálculo do valor da MDCI pelo método da pergunta âncora, na amostra avaliada, foi de 5,5 para o escore de Lysholm. Não foi possível determinar o valor da MDCI para o IKDC.

Monoaxial Mechanical Tests on Porcino Knee Ligaments / Ensaios mecânicos monoaxiais nos ligamentos do joelho porcino

Abstract The failure of ligament reconstruction has different risk factors, among which we can highlight the period before its incorporation, which is a mechanically vulnerable period. Loss of resistance over time is a characteristic of living tissues. Dissection with bone insertions of the cruciate ligaments of animal models is not described; however, it is essential for monoaxial assays to extract information from tests such as relaxation. The present work describes the dissection used for the generation of a test body for the performance of nondestructive tests to evaluate the mechanical behavior. We performed dissection of four porcino knee ligaments, proposing a dissection technique for the cruciate ligaments with bone inserts for comparison with collateral ligaments. The ligaments were submitted to relaxation tests and had strain gauges placed during the tests. The results showed viscoelastic behavior, validated by strain gauges and with a loss over time; with some ligaments presenting with losses of up to 20%, a factor to be considered in future studies. The present work dissected the four main ligaments of the knee demonstrating the posterior approach that allows maintaining their bone insertions and described the fixation for the monotonic uniaxial trials, besides being able to extract the viscoelastic behavior of the four ligaments of the knee, within the physiological limits of the knee.

Resumo A falha da reconstrução ligamentar tem diferentes fatores de risco, dentre os quais podemos destacar o período antes da sua incorporação, o qual configura um período mecânico vulnerável. A perda de resistência ao longo do tempo é uma característica dos tecidos vivos. A dissecção com as inserções ósseas dos ligamentos cruzados de modelos animais não é descrita; todavia, para os ensaios monoaxiais, é fundamental extrair as informações de ensaios como os de relaxação. O presente trabalho realiza a descrição da dissecção utilizada para a geração de corpo de prova para a realização de ensaios não destrutivos para avaliar o comportamento mecânico. Realizamos dissecção de quatro ligamentos de joelho porcino, propondo uma técnica de dissecção para os ligamentos cruzados com as inserções ósseas para comparação com os colaterais. Os ligamentos foram submetidos a testes de relaxação e foram colocadas strain gauges durante os testes. Os resultados mostraram comportamento viscoelástico, validado pelas strain gauges e com uma perda ao longo do tempo, sendo que, em alguns ligamentos, as perdas chegaram a até 20%, fator este a ser considerado em trabalhos futuros. O presente trabalho dissecou os quatro principais ligamentos do joelho, demonstrando a abordagem posterior que permite manter as suas inserções ósseas e descrevendo a fixação para os ensaios uniaxiais monotônicos, além de ter conseguido extrair o comportamento viscoelástico dos quatro ligamentos do joelho dentro dos limites fisiológicos do joelho.

Anatomy of the perforator propeller flap of superior lateral genicular artery and its clinical application in repair of soft tissue defect of anterolateral knee / 中华显微外科杂志

Objective:To study the anatomy of the perforator propeller flap of superior lateral genicular artery, and to explore a surgical method and clinical application in repair of the soft tissue defect of anterolateral knee with the flap.Methods:From September 2019 to September 2021, 8 knees of 4 chilled fresh specimen of adults were studied. The perforators of the superior lateral genicular artery were observed. The length, outer diameter of the perforators, and the locations of the skin perforation were recorded. The superior lateral genicular artery perforator propeller flaps were then applied clinically to 5 patients(3 males and 2 females) with soft tissue defects of anterolateral knee. Two of the patients had combined ligament injury and(or) bone joint exposure. The age of patients ranged from 25 to 48 years old, at 33.4 years old in average. The sizes of soft tissue defects ranged from 4.0 cm×4.0 cm to 8.0 cm×5.0 cm. The sizes of perforator propeller flaps of superior lateral genicular artery were 10.0 cm×5.0 cm to 13.0 cm×6.0 cm. The superior perforating vessels of the superior lateral genicular artery were found and marked at the points of skin perforation. Preoperative contrast-enhanced ultrasound were performed to confirm the dominant perforating vessels and had the skin perforating points marked. Intraoperative CDU were further performed to confirm the points of dominant perforating vessels. Perforator propeller flaps were designed depending on the size of the anterolateral soft tissue defect, and flaps were prepared and transferred to the defect sites. Postoperative follow-ups were conducted at outpatient clinic. The survival of the flap and knee function were observed according to the Bai-ly knee scoring.Results:The anatomy showed that an average pedicle length of the superior lateral genicular artery perforator was(8.2±0.9) cm, with an average starting outer diameter at(1.1±0.2) mm. All 5 flaps survived during the follow-up that lasted for 10 to 24 months, with an average of 15.3 months. All flaps healed in 2 weeks after surgery without complications such as soft tissue infection, bone and joint infection were observed. At the last follow-up, no obvious bloated appearance of the flaps were observed. The colour and elasticity of the flaps were similar to the surrounding skin. The knee function was assessed: 4 patients were in excellent and 1 in good. The range of knee flexion and extension was from 100° to 150°. The patients were satisfied with the appearance and function of the knees.Conclusion:The size of the perforator of superior lateral genicular artery and the pedicle length are ideal. The propeller flap can be used to repair the soft tissue defect around the anterolateral knee, with satisfactory functional recovery of a knee. It is a good method to repair the soft tissue defect around anterolateral knee.

Progress in extension lag after knee surgery / 中华骨科杂志

Most literature defines knee extension lag as the failure of the knee joint to achieve the passive extension angle, and some literature defines the inability of the knee to complete the last 15° extension as knee extension lag. Extension lag is one of the common complications after knee surgery, which seriously affects the postoperative knee joint function of patients. Disuse atrophy due to prolonged postoperative bed rest, arthrogenic muscle inhibition due to pain and (or) swelling, direct injury to the knee extensor mechanism during surgery and nerve dysfunction of the quadriceps muscle can all contribute to extension lag. While rehabilitation exercises, physical therapy and medication can significantly improve the patient's symptoms, extension lag due to the knee extension device injury requires surgery if necessary to regain normal knee function. As surgical techniques continue to be refined and rehabilitation interventions advance, the prevention of extension lag and the minimization of angle of knee extension lag need to be given adequate attention by patients, physicians, and researchers. This article reviews clinical studies related to extension lag after knee surgery, focusing on etiology, treatment, prevention and prognosis, with the aim of providing a basis and guidance for the current clinical management.

All-inside versus full-tibial tunnel techniques of anterior cruciate ligament reconstruction: a systematic review and meta-analysis / 中华骨科杂志

Objective:To compare the clinical efficacy of arthroscopic all-inside technique versus full-tibial tunnel technique for anterior cruciate ligament (ACL) reconstruction.Methods:Literature on all-inside versus full-tibial tunnel for ACL reconstruction was retrieved from databases including China National Knowledge Infrastructure (CNKI), Wanfang Data, Full-text Database of Chinese Medical Journals, PubMed, Web of Science, and Cochrane Library from their establishment to February 2023. Meta-analysis was performed on the included studies. Random effects model was used if heterogeneity was large, while fixed effects model was used if heterogeneity was small.Results:A total of 13 studies with 511 cases in the all-inside group and 465 cases in the full-tibial tunnel group were included in the meta-analysis, with a mean follow-up of 6-25.8 months. Meta-analysis showed that the graft diameter [ MD=0.42, 95% CI (0.11, 0.73), P=0.007] and International Knee Documentation Committee (IKDC) subjective score [ MD=1.11, 95% CI (0.36, 1.86), P=0.004] of the all-inside group was larger than full-tibial tunnel group, and the tibial tunnel widening of the all-inside group was less than full-tibial tunnel group [ MD=-1.70, 95% CI (-2.38, -1.01), P<0.001]. There were no significant differences in IKDC objective score [ OR=1.09, 95% CI (0.67, 1.78), P=0.730], Lysholm score [ MD=0.99, 95% CI (-0.08, 2.05), P=0.070], Tegner activity score [ MD=-0.01, 95% CI (-0.48, 0.45), P=0.950], bilateral knee anterior laxity difference [ MD=0.32, 95% CI (-0.22, 0.86), P=0.250], negative rate of pivot shift test [ OR=0.80, 95% CI (0.33, 1.91), P=0.610], graft re-rupture rate [ OR=0.76, 95% CI (0.34, 1.74), P=0.524] and return to sport rate [ OR=1.56, 95% CI (0.85, 2.86), P=0.150]. Conclusion:All-inside ACL reconstruction provides satisfactory efficacy. Compared with full-tibial tunnel technique, it has the advantages of larger graft diameter and less tibial tunnel widening, with no difference in joint function within 2 years postoperatively.

Design and clinical application of the distal femur spherical motion axis hinge knee prosthesis / 中华骨科杂志

Objective:To investigate the feasibility and early clinical efficacy of spherical motion axis hinge knee prosthesis to reconstruct distal femoral bone defects.Methods:A retrospective analysis was performed on 16 patients admitted to PLA 960th Hospital and Tianjin Hospital from October 2019 to November 2021, including 8 males and 8 females, with an average age of 43.3±17.8 years (range, 15-71 years). There were 13 patients of primary tumors of the distal femur and 3 patients of postoperative revision of knee joint prostheses. Among the 13 patients with distal femur tumors, there were 6 cases of osteosarcoma, 5 cases of giant cell tumor of bone, 1 case of leiomyosarcoma and 1 case of chondrosarcoma. The reasons for revision after prosthesis replacement in 3 cases were: 2 cases of aseptic loosening after tumor-type prosthesis and 1 case of periphery fracture of surface artificial knee prosthesis. A spherical shaft rotary hinged knee prosthesis was designed and fabricated to reconstruct postoperative femoral defects in 16 patients. Follow up regularly after the operation, recheck the X-ray film to evaluate the lower limb force line, evaluate the quality of life after the operation with the Chinese version of 36-item short-form (SF-36), and evaluate the postoperative limb function with the Musculoskeletal Tumor Society (MSTS) 93 evaluation system.Results:All 16 patients were successfully placed with prostheses, and except for 2 patients undergoing total femoral replacement, the length of bone defects was 18.2±11.7 cm (range, 8.6-47.1 cm) in other 14 patients, and the operation time was 138±19 min (range, 110-170 min), the intraoperative blood loss was 211±118 ml (range, 100-500 ml). The postoperative full length orthostatic X-ray film of the lower limbs showed that the distance between the mechanical axis of the lower limb and the center of the knee joint was 0.1 (0, 0.7) cm in 16 patients, and the hip-knee ankle angle was 179.0°±2.3°(range, 173.3°-182.2°). The patients were followed up for 12-36 months. No prosthesis complications were found in 16 patients. The SF-36 score was 56.7±7.0 (range, 42.7-67.4) for physiological function and 54.1±7.6 (range, 40.5-66.3) for psychological function. The maximum knee flexion angle was 120.0°±15.6° (range, 95°-130°). The MSTS 93 score of 15 patients with tumor was 25.0±1.7 (range, 22-28), including 7 excellent and 8 good. One patient developed liver and lung metastases 10 months after surgery and died 18 months after surgery. The remaining patients, as of the last follow-up, were alive and had no local recurrence or distant metastases. Tumor-free survival time was 25.8±8.4 months (range, 12-36 months).Conclusion:The spherical motion axis hinge knee prosthesis reconstruction for distal femoral bone defects is simple and fast in intraoperative prosthesis installation, and there are no prosthetic related complications during short-term follow-up. The clinical efficacy is satisfactory.

Evaluation of utilizing cement-in-cement technique for endoprosthetic revision surgeries around the knee / 中华骨科杂志

Objective:To investigate the clinical efficacy of cement-in-cement (CiC) technique for endoprosthetic revision surgeries of noninfectious causes around the knee.Methods:All of 128 patients who had received cement-in-cement technique for endoprosthetic revision from February 2002 to August 2020 including 71 males and 57 females, whose mean age was 33.5±15.4 years (range, 8-77 years). 128 patients included 73 cases of osteosarcoma, 38 cases of giant cell tumors, 8 cases of undifferentiated sarcoma, 4 cases of chondrosarcoma, 2 cases of Ewing sarcoma, 2 cases of fibrosarcoma and 1 case of synovial sarcoma, with 105 cases in distal femur and 23 cases in proximal tibia. The failure mode classification included 64 cases of aseptic loosening, 47 cases of structure failure and 17 cases of tumor progression. 16 out of the 19 endoprosthese failure after the first cement-in-cement procedure received a second cement-in-cement procedure. The survival of revised prostheses, duration of the operation, the amount of blood loss, epidemiological data, complications and limb function were enrolled and statistical analyzed.Results:The mean follow-up from CiC revision was 127±33 months (range, 6-326 months). There were 25 (19.5%) complications for the first CiC procedure and 19 (14.8%) of the 25 complications lead to the protheses failure including 5 (3.9%) structure failure, 6 (4.7%) aseptic loosening, 2 (1.6%) tumor recurrence and 6 (4.7%) infection. The other 6 cases included 5 poor superficial wound healing and 1 patellar ligament rupture. All were recovered after debridement and tendon repair. The cumulative survival rates of first CiC procedure were 85.0%, 76.6% and 70.7% at 5, 10 and 15 years, respectively. Limb salvage rate was 97.7%. Sixteen of the 19 cases received a second CiC revision. The mean operative time (206±51 min vs. 258±41 min, t=3.18, P=0.399), blood loss (596±217.99 ml vs. 621±245.84 ml, t=0.30, P=0.926) and the median MSTS 93 score (26.38±2.47 vs. 25.06±2.11, t=1.61, P=0.376) of the first and second CiC procedure for the 16 cases were similar. Conclusion:CiC technique is a repeatable, conservative and viable option for endoprosthetic revision surgeries of noninfectious causes around the knee, with acceptable prosthetic survival rate, complication rate and limb function.

Methods of reducing the "killer turn" effect in the posterior cruciate ligament reconstruction / 中华骨科杂志

The reconstruction of the posterior cruciate ligament (PCL) through the tibial tunnel is the most commonly used reconstruction technique after ligament injury.However, when the graft passes through the tibial tunnel back to the medial condyle of the femur, a sharp angle is formed at the proximal end of the tibia, called the "killer turn". The existence of the "killer turn" can lead to graft wear and expansion of adjacent tibial tunnel after PCL reconstruction, affecting the stability of the posterior knee joint after operation and even leading to the failure of operation. There are several techniques, such as modifified tibial tunnel technique which the proximal exit of tibial tunnel is located in the inferior and lateral aspect of the PCL tibial anatomic insertion site, increasing the angle between the tibial tunnel and the tibial plateau, creating a tibial tunnel from the anterior lateral side of the tibia, remnant preserving as soft tissue cushion, and inlay and onlay techniques for reconstructing PCL without using tibial tunnel reconstruction, can reduce the "killer turn" effect. The above 6 techniques, theoretically, can effectively reduce or eliminate the "killer turn" effect and improve the posterior stability of the knee joint after PCL reconstruction, so as to improve the clinical efficacy of PCL reconstruction. But, the number of cases using these techniques is relatively small, and their effectiveness, reliability, and advantages and disadvantages for patients still need more clinical practice to further explore and verify.

Causes analysis and coping strategies of posterior laxity after posterior cruciate ligament reconstruction / 中华骨科杂志

It is difficult to maintain the initial posterior stability of the knee after posterior cruciate ligament reconstruction. Residual posterior knee laxity after operation is a problem of PCL reconstruction. It not only results in abnormal kinematics of the knee, but also leads to secondary meniscus injury and cartilage degeneration of the affected knee, and eventually leads to knee osteoarthritis, which may especially happen with persistent and severe posterior laxity. The main reasons of residual posterior knee laxity after PCL reconstruction are: improper treatment of the posterolateral corner injury, poor positioning of the femoral tunnel, small tibial slope, and unreasonable postoperative rehabilitation. There are some concepts and technologies, such as using artificial ligaments, tibial tunnel fixation with suspensory device or suspensory device combined with interference screws, enlargement of graft diameter, all-inside reconstruction combined suture augmentation, slow and gradual postoperative rehabilitation, which can eliminate or reduce the postoperative residual laxity, in order to improve clinical outcomes after PCL reconstruction. For the patients with flat tibial slopes, double-bundle PCL reconstruction and concurrent slope-increasing tibial osteotomy is suggested. It can reduce the risk of posterior laxity and improve the stability of the knee after operation.

All-inside anterior cruciate ligament reconstruction: a review of development, evolution and clinical significance / 中华骨科杂志

Rupture of anterior cruciate ligament (ACL) is one of the most common sports injuries of the knee, which may cause limitation of motor function and degeneration of the knee, seriously affecting patients' living quality. Currently, arthroscopic ACL reconstruction (ACLR) has been identified as the gold standard for ACL rupture. In an effort to further increase surgical accuracy and decrease surgical trauma so as to promotes quick recovery, all-inside ACLR has gained increasing attention in recent years. All-inside ACLR is as effective as traditional reconstruction, but it has benefits such as the preservation of tendons, preservation of bone mass, reduction of postoperative pain, prevention of synovial fluid leakage, expansion of the tendon-bone healing area, avoidance of complications related to extrusion screws, and suitability for children and adolescents. However, applying of numerous novel techniques for all-inside ACLR increases the learning curve, operating time, and cost. Besides, improper bone tunnel fabrication and graft fixation may lead to the widening of the bone tunnel, affecting the surgical effect. Therefore, in order to provide a theoretical foundation for further promoting the clinical application of this technique, this article reviews the development, evolution, and clinical outcomes of this technique as well as its advantages and disadvantages.

Evaluation of knee cartilage based on MRI artificial intelligence reconstruction model of knee joint / 中华骨科杂志

Objective:To explore the feasibility of the AI intelligent reconstruction model based on knee joint magnetic resonance data developed by Nuctech Company Limited for evaluating knee cartilage injury.Methods:Thirty-three patients (a total of forty-one knees) who were hospitalized with severe knee osteoarthritis in Beijing Tsinghua Changgung Hospital from May 2021 to April 2022 were selected. All of them were planned to be performed total knee arthroplasty (TKA) for the treatment of knee osteoarthritis. Fifteen males with an average age of 71±5 years old and twenty six females with an average age of 71±9 years old were included in this study. There were 19 cases of left knee and 22 cases of right knee. Thin layer MRI examination on the patients' knee joints was performed before the surgery, and artificial intelligence model based on the thin layer MRI data of the knee joint was reconstructed. The cartilage part of the model was selected and corrected by Principal Component Analysis (PCA) in order to realize model straightening. The tibial plateau cartilage of knee joint which intercepted during operation was classified according to the International Cartilage Repair Society (ICRS). Finally the results were compared with the ICRS classification results of knee artificial intelligence reconstruction model and artificial recognition of knee joint MRI images.Results:Compared with the grade of cartilage injury intercepted during our operation which was according to the ICRS classification, the sensitivity of artificial intelligence reconstruction model for the diagnosis of cartilage injury with ICRS classification grade four was 93.1%. The specificity of artificial intelligence reconstruction model was 91.4%. The positive predictive value (PPV) of artificial intelligence reconstruction model was 92.2%. And the negative predictive value (NPV) of artificial intelligence reconstruction model was 80.3%. The area under ROC curve (AUC) was 0.92. The ICRS classification consistency between artificial intelligence model and physical inspection results was good with kappa value 0.81 ( P<0.001) . In the aspect of artificial recognition of cartilage injury grading in MRI images, the sensitivity of artificial recognition was 92.10% compared with the manual identification of cartilage injury classification in MRI images. The specificity of artificial recognition was 91.60%. The positive predictive value (PPV) of artificial recognition was 97.20% and the negative predictive value (NPV) of artificial recognition was 78.8%. The kappa value of the cartilage injury classification in MRI images consistency between artificial recognition and manual identification was 0.79 ( P<0.001). Conclusion:Based on the evaluation of cartilage injury by AI reconstruction model of knee joint, the sensitivity and specificity of the diagnosis of ICRS grade IV cartilage injury can be acceptable, but still needs to be improved.

Navigation-assisted valgus stress method can avoid over correction of high tibial osteotomy / 中华骨科杂志

Objective:To explore the role of navigation-assisted valgus stress method in avoiding excessive correction of lower limb mechanical axis after high tibial osteotomy (HTO).Methods:A retrospective study was carried out on osteoarthritis (OA) patients who were treated with HTO for medial compartment pain of knee from January 2020 to March 2022 in the Department of Joint Surgery, Shanghai Changhai Hospital, the First Affiliated Hospital of Naval Medical University. According to the different ways of confirming alignment during operation, they were divided into computer navigation assisted valgus stress HTO group (referred to as navigation group) and traditional rod fluoroscopy HTO group (referred to as traditional group). There were 28 patients in the navigation group, 10 males and 18 females, with age of 54.4±9.1 years (range, 41-73 years) and body mass index of 26.1±3.3 kg/m 2 (range, 19.8-35.2 kg/m 2); There were 30 patients in the traditional group, 13 males and 17 females, aged 56.9±8.5 years (range, 40-70 years), with a body mass index of 25.7±4.0 kg/m 2 (range, 19.2-32.9 kg/m 2). Measuring the mechanical femoral tibial angle (mFTA), joint line convergence angle (JLCA), medial proximal tibial angle (MPTA), Lysholm score and Hospital for Special Surgery (HSS) score before operation and at the last follow-up of the two groups, and conduct statistical analysis. Results:Both groups were followed up. The follow-up time of navigation group and traditional group was 21.3±8.7 months and 22.5±7.6 months, respectively, with no significant difference ( t=0.53, P=0.596). There were significant differences between the two groups in the amount of mechanical axis correction (ΔmFTA) and the amount of bone correction (ΔMPTA) ( t=2.09, P=0.041; t=2.58, P=0.012), while there was no significant difference in ΔJLCA ( t=0.32, P=0.753). In the navigation group, there were 9 cases (32%) of undercorrection, 17 cases (61%) with acceptable alignment, and 2 cases (7%) with over correction, while in the traditional group, there were 5 cases (17%) with under correction, 13 cases (43%) with acceptable alignment, and 12 cases (40%) with over correction. There was significant difference in the distribution rate of alignment between the two groups ( P=0.012), and the rate of overcorrection in the navigation group was significantly lower than that in the control group (7% vs. 40%, P=0.005). The intra group correlation coefficient between the navigation correction mechanical axis and ΔmFTA was 0.787. There was no significant difference in Lysholm score and HSS score between the two groups before and after surgery (all P>0.05), and they were significantly improved after operation (all P<0.05). Conclusion:Navigation-assisted valgus stress method HTO is reliable, which can accurately achieve the target alignment, reduce the incidence of over correction, and obtain good clinical results.

Consistency study of FRACTURE sequence and CT in evaluating bone changes of knee and ankle / 中华放射学杂志

Objective:To explore the consistency of MRI fast field echo resembling a CT using restricted echo-spacing (FRACTURE) and CT in the evaluation of knee and ankle bone changes.Methods:From November 2020 to November 2021, seventeen patients who underwent CT and MRI FRACTURE examinations of knee joint or ankle joint in the First Affiliated Hospital of Dalian Medical University were retrospectively collected, including 14 patients with knee joint examinations and 3 patients with ankle joint examinations. According to the number of joint components, 80 components were included, including 14 for femur and patella, 17 for tibia and fibula, and 3 for talus, scaphoid, medial cuneiform, medial cuneiform, lateral cuneiform and calcaneus, respectively. The fracture, hyperosteogeny, and bone destruction of the joint bones were evaluated by two observers using CT and FRACTURE images, respectively. Kappa test was used to analyze the consistency of CT and FRACTURE images between observers in the evaluation of joint bone lesions.Results:The Kappa values (95%CI) of the consistency evaluation of fracture, hyperosteogeny, and bone destruction by CT and FRACTURE images were 0.925 (0.823-1.027), 0.905 (0.799-1.011) and 0.895(0.752-1.038) respectively for observer 1, and were 0.963 (0.892-1.034), 0.933 (0.843-1.023) and 0.886 (0.731-1.041) respectively for observer 2. The Kappa values (95%CI) of the consistency evaluation of fracture, hyperosteogeny, and bone destruction by observers 1 and 2 via CT images were 1.000 (1.000-1.000), 0.937(0.851-1.023) and 0.945 (0.839-1.051) respectively, and that by FRACTURE images were 0.962 (0.888-1.036), 0.966 (0.899-1.033) and 0.836 (0.656-1.016) respectively.Conclusion:For the evaluation of fracture, hyperosteogeny, and bone destruction of knee joint and ankle joint, MRI FRACTURE sequence is highly consistent with CT.