Método fácil para la medición de las deformidades angulares de la rodilla / Easy method to measure angular knee deformities

RESUMEN Fundamento: las deformidades angulares de la rodilla son muy frecuentes en pacientes con artrosis, existen varios métodos de medición clínicos y radiográficos, con características propias. Objetivo: proponer un método de medición para la desviación angular de la rodilla que sea fácil y rápido. Métodos: la búsqueda y revisión de la información se realizó en un periodo de cuatro meses (primero de abril de 2018 al 30 de junio de 2018) y se emplearon las siguientes palabras: knee angular deformities, measurement of knee deformities, measures and knee angular deformities, a partir de la información obtenida se realizó una revisión bibliográfica de un total de 213 artículos publicados en las bases de datos PubMed, Hinari, SciELO y Medline mediante el gestor de búsqueda y administrador de referencias EndNote, de ellos se utilizaron 32 citas seleccionadas para realizar la revisión, 29 de los últimos cinco años. Desarrollo: se describen las características clínicas y radiográficas de los pacientes con desviación angular de la rodilla. En caso de las radiografías se hace referencia a la vista específica para la medición de esta deformidad. Se mencionan las ventajas y desventajas de los métodos de medición del eje mecánico y anatómico. Basados en la revisión de este tema, se propone un método de medición que puede ser llevado a cabo en radiografías digitales y películas. Conclusiones: el método propuesto es aplicable a nuestro medio y puede ser llevado a cabo en radiografías digitales y películas radiográficas.

ABSTRACT Background: knee angular deformities are common in patients suffering from osteoarthritis. There are many clinic and radiographic methods to measure knee deformities, each one has its own features. Objective: to propose an easy and quick method to measure angular knee deformities. Methods: a four month research was conducted from April 1st, 2018 to June 30th, 2018. It was included 213 articles published in PubMed, Hinari, SciELO and Medline databases using EndNote. The words used were knee angular deformities, measurement of knee deformities, measures and knee angular deformities. Thirty two citations were selected for the review, of them twenty nine within the last five years. Development: clinical and radiographic features in patients with angular deformities were described. Specific X-ray view features were pointed out to measure deformity. Advantages and disadvantages about mechanic and anatomic axis measures were mentioned. Based on literature review a new method is proposed to be used in digital and plain radiographic slides. Conclusions: the proposed measure method can be used in digital and plain radiographic slides at our health institutions.

MR Findings of Bland and Proliferative Joint Effusion in Knee Joint

PURPOSE: To determine the MR imaging criteria by which bland and proliferative effusion of the knee may be differentiated. MATERIALS AND METHODS: We retrospectively reviewed the MR images of 64 patients (65cases), in whom T2-weighted sagittal scans revealed anteroposterior distension of the suprapatellar bursa of at least 0.5cm. The patients were divided into two groups: bland effusion (n=36) , and proliferative effusion [(n=29); pigmented villonodular synovitis (n=5), rheumatoid arthritis (n=6), septic arthritis (n=6), chronic synovitis (n=5), gouty arthritis (n=3), tuberculous arthritis (n=2), and lipoma arborescens (n=2)]. All conditions were diagnosed on the basis of operative data or clinical criteria. The knee joint space was divided into four compartments: the suprapatellar pouch, central zone, posterior femoral recess, and subpopliteal recess, and the amount and distribution of effusion was then compared between the two groups. The ratios of the width and the length of the lateral recess of the suprapatellar bursa to those of its medial recess were deter mined, and the findings for the two groups were compared. Abnormality of the intracapular fat pads (prefemoral fat, Hoffa 's fat, and quadriceps fat sign) as seen on sagittal scans, is a predictor proliferative effusion, and any such abnormality was evaluated. The synovium was classified as either thin or thick, and as having either a smooth or an irregular margin, as seen on Gadolinium-enhanced T1W1 images. RESULTS: As compared with bland effusion, proliferative effusion involved more prominent joint effusion in the suprapatellar pouch and posterior femoral recess, and in the suprapatellar bursa, the ratio of the width of the lateral recess to that of the medial recess was greater. When comparing the ratio of the length of the lateral recess to that of the medial recess, however, no significant statistical difference was noted. Sensitivity: specificity for proliferative effusion was 58%: 86% on coronal scan and 64%: 93% on axial scan at a threshold value of 0.7 (the ratio of the width). The prefemoral fat pad sign was 41% sensitive and 100% specific, while Hoffa 's fat pad sign had a sensitivity of 32% and a specificity of 95%. The corresponding figures for the quadriceps fat pad sign were 14% and 100%. The pattern of the synovium in bland effusion was thin and smooth in two, thick and smooth in one, and thin and irregular in one. In proliferative effusion, the pattern was thick and smooth in 11 cases, thin and irregular in four, and thick and irregular in 14. CONCLUSION: In proliferative effusion, the synovium tended to be thick and irregular. Proliferative effusion demonstrated greater predilection for the suprapatellar pouch, especially the lateral recess, and posterior femoral recess, than did bland effusion. Difference in the distribution of joint effusion effectively predict both proliferative effusion as well as intracapsular fat pad signs.

Analysis of MR Imaging with FSE and DESS for the Diagnosis of Meniscal Tears in 316 Patients

PURPOSE: To evaluate the accuracy of a magnetic resonance(MR) imaging strategy that primarily uses fast spinecho(SE) sequences for the diagnosis of meniscal tears. MATERIALS AND METHODS: The original clinical interpretations of MR images in 316 patients who underwent imaging for suspected internal derangement of a knee joint were correlated with results from subsequent arthroscopy (mean interval : 48.9 days). In all patients, MR examinations included double-echo fast SE T2- weighted sagittal and coronal imaging and double-echo steady state (DESS) sequence sagittal imaging. In 199 patients fat-suppressed conventional SE T1-weighted sagittal imaging was used. In cases in which interpretation was erroneous, imaging findings and arthroscopy reports were reviewed. RESULTS: For ISO confirmed tears of the medial meniscus, sensitivity, specificity, and accuracy were 94 %, 93 %, and 94 %, respectively, while respective values for 147 confirmed tears of the lateral meniscus were 85%, 97 %, and 91%. These values are within the ranges recently reported for imaging strategies relying predominantly on conventional SE sequences. Of the 12 false-positive tears of the medial meniscus, five menisci showed a high signal contacting the surface on only one image and seven, that in all cases were located in the periphery of the posterior horn, showed such signal on more than one image. Of the six false-positive tears of the lateral meniscus, three menisci showed a high signal contacting the surface on only one image. Of the nine false-negative tears of the medial meniscus, eight menisci showed an abnormal signal that did not demonstrate definitive contact with the surface. Of the 22 false-negative tears of the lateral meniscus, 18 menisci showed this same type of signal. CONCLUSION: Fast SE imaging of the knee can be an alternative to conventional SE imaging for the detection of meniscal tears. Most errors in our series were due to either an abnormal signal that failed to show definitive contact with the surface, a high signal which contacted the surface on only one image, or a signal of this type that was located in peripheral posterior horn of the medial meniscus, on more than one image.

MR Findings of Chondromalacia Patella: Correlation of the Grade and Associated Lesions with ArthroscopicFindings

PURPOSE: To assess the MR findings of chondromalacia patella and correlate the grade and associated lesionswith the arthroscopic findings. MATERIALS AND METHODS: Twenty-five patients with pain in the anterior part of theknee underwent fat-suppressed axial and coronal T2-weighted, dual echo sagittal proton density-weighted andT2-weighted, and in some cases, T1-weighted and T2*-weighted imaging, using a 10-cm field of view, and a 5-inchgeneral purpose coil. We retrospectively assessed these find dings, and the locations, grades and associatedlesions, and correlated these with the arthroscopic findings. RESULTS: Fourteen cases(56%) of chondromalaciapatellae were arthroscopic grade I / II, nine(36%) were grade III, and two(8%) were grade IV; associated lesionswere medial synovial plicae (16 cases, 64%), meniscus tear (10 ; 40%), cruciate ligament injury (two ; 8%),complete or incomplete discoid meniscus (four ; 16%), bipartite patella (one ; 4%) and Osgood-Schlatter disease(one ; 4%). In 24 cases, MR imaging indicated chondromalacia patella ; 17 cases were grade I / II, five were gradeIII, and two were grade IV. the location of chondromalacia patella was the medial facet (five cases ; 20%), lateralfacet (three ; 12%), junction of the medial and odd facet (13 ; 52%), and diffuse involvement (four ; 16%). Thesensivity and specificity of MR imaging were 72% and 96% respectively. CONCLUSION: We evaluated the exact locationand grade of chondromalacia patella and associated lesions, as seen on MR images. These and the arthroscopicfindings showed close correlation, and in cases involving this condition, MRI is thus a useful indicator of anappropriate surgical method and plan.