La ultrasonografía en el estudio de rodilla dolorosa / Ultrasonography in the study of painful knee

La presencia de dolor y/o tumefacción a nivel de la rodilla es un motivo de consulta frecuente, ya sea en pacientes con enfermedad reumatológica definida o en la población general. Si bien la rodilla es una región accesible para el examen clínico, la ultrasonografía se ha convertido en una herramienta de gran ayuda para el reumatólogo al momento de definir el origen del dolor y/o la tumefacción, ya que permite detectar inclusive mínimas alteraciones morfoestructurales a nivel de las distintas estructuras anatómicas de la rodilla. En la práctica clínica es importante destacar la importancia de la ultrasonografía para la detección de sinovitis y entesopatía subclínicas en las artropatías inflamatorias, así como para demostrar cambios mínimos sugestivos de artropatía degenerativa y microcristalina. Por otra parte, esta técnica es de suma utilidad en la determinación del origen de los distintos síndromes regionales dolorosos y es una herramienta eficaz como guía para el intervencionismo diagnóstico y/o terapéutico. La ultrasonografía cuenta con muchas ventajas, tales como la inocuidad, el bajo costo operativo y la posibilidad de estudiar múltiples regiones en tiempo real y dinámico; sin embargo, en la actualidad, la larga curva de aprendizaje quizás sea una de sus mayores limitaciones.

The presence of knee pain and/or swelling is an important reason of attendance in rheumatologic daily practice. Although knee is an accessible region to be evaluated by the physical examination ultrasonography has been converted in an excellent and helping tool for the rheumatologists in order to establish the origin of the knee pain and/or swelling. Ultrasonography has the ability to detect subclinical synovitis and enthesopathy in patients with inflammatory arthritis and to demonstrate minimal changes indicative of degenerative or mycrocristaline arthropathies. Moreover, ultrasonography can be useful to determinate the cause of the different pain regional syndromes and is a very good option to be used as guide for the interventional arthrocentesis. Ultrasonography has several advantages as safety, low cost and the capability to study many joints in a realtime. However, at the present the large learning curve might be one of the main limitations.

Variability in the cell phenotype of aggregates or "clones" of human osteoarthritic cartilage. A case report

Human samples of articular cartilage from the knee of a clinically classified osteoarthritic patient, assessed by arthroscopy as part of the surgical treatment was studied by light and transmission electron microscopy. This particular case differed from others already reported in the variability of cell phenotype within the aggregates or "clones" frequently present in the osteoarthritic cartilage. The most common morphology of "clonal" cells forming the aggregates were large and rounded with an euchromatic nucleus. The cytoplasm was characterized by the presence of alternately clear and dense sites. At the ultrastructural level it was seen that the clear sites were formed by disrupted intermediates filaments and small particles, and that the dense sites were constituted by the segregation of different organelles of the chondrocytes. In addition, there were atypical aggregates composed only by secretory cells or by degenerating chondrocytes. Furthermore, a complex structure consisting of a very large cell inside a giant lacunae delimited by electron-dense material with small vesicles is described as a novel finding. The variability in the chondrocyte phenotype of the aggregates described here could be an indication of a better prognosis; nevertheless, the follow-up of the evolution of this patient is needed in order to know the final outcome.

Nuevos conceptos en la etiopatogenia de la artrosis / New concepts in the etiopatogenic of the osteoarthritis

Son múltiples los agentes nocivos que pueden desencadenar una lesión artrósica, pero no en forma aislada y sin un terreno que predisponga al paciente. Sin embargo, nuestros estudios estructurales del cartílago indican que el centro de la lesión artrósica es el condrocito, y que independientemente de cuáles sean los factores etiopatogénicos, debe ocurrir una alteración de la interfase hueso-cartílago para que se produzcan daños en este tejido, y se altere, rompiéndose el equilibrio cuya consecuencia son las alteraciones descritas