Resumen de Indicación y resultados de la prótesis con estabilidad aumentada en la artroplastia primaria de rodilla. [Constrained prosthesis primary total knee arthroplasty.]

Santiago Vedoya, Germán Garabano, Hernan del Sel

• español

  Introducción:Presentamos los resultados funcionales y criterios de indicación para artroplastía de rodilla con estabilización superior al estabilizado posterior, en la artroplastia de rodilla primaria (ATR).Materiales y métodos:Análisis retrospectivo de 43 ATR en 40 pacientes, con seguimiento promedio de 6,2 años. 38 casos presentaban genu valgo artrósico y 5 genu varo artrósico. La suficiencia de los ligamentos colaterales se definió como suficiente, atenuado o incompetente. Se desarrollo un sistema de clasificación para los genu valgo que relacionara el tipo de rodilla con el implante elegido. ResultadosSe utilizaron 28 prótesis con estabilización posterior plus en pacientes con un deseje coronal promedio de 15.9°, de los cuales 21 presentaron ligamentos suficientes y 5 atenuados.Se utilizo una prótesis constreñida en 7 pacientes con deseje en valgo promedio de 21.6°, 2 con ligamentos suficientes y 5 con ligamentos atenuados.Se utilizaron 8 prótesis abisagradas rotatorias, 5 en pacientes con un genu valgo promedio de 24.6° (3 de ellas asociadas a recurvatum), 4 con ligamentos incompetentes y una con ligamentos atenuados, y tres con genu varo de 16° promedio. Conclusiones:Recomendamos utilizar las prótesis estabilizadas plus en desejes < 20°, con ligamentos colaterales suficientes en ausencia de defectos óseos. Las prótesis constreñidas en pacientes con grandes desejes con ligamentos colaterales que presenten algún grado de suficiencia (a lo sumo atenuados). Las prótesis abisagradas rotatorias las reservamos para rodillas con incompetencia ligamentaria colateral o multidireccional, grandes defectos óseos o deformidades severas en artritis reumatoide o de origen neuropático. AbstractIntroduction: The objective of this retrospective study was to show the functional results and indication criteria for prostheses for primary TKA with more constraint than posterior stabilization.Methods: Forty-three TKA were analyzed in 40 patients, with an average follow-up of 6.2 years. Preoperative diagnoses were valgus osteoarthritis (38 cases) and varus osteoarthritis (5 cases). Sufficiency of the collateral ligaments was classified as sufficient, attenuated or incompetent, through physical examination and X-rays with varus-valgus stress. Functional results were evaluated using the KSS.Results: Posterior-stabilized plus implants were used in 28 cases, with an average alignment of 15.9°: 26 were valgus knees, 21 of which presented sufficient and 5 attenuated ligaments. Constrained prostheses were used in 7 patients with an average valgus alignment of 21.6° (2 with sufficient and 5 with attenuated ligaments). Rotating-hinge prostheses were used in 8 patients, 5 with an average valgus alignment of 24.6° (3 of them associated with recurvatum), 4 with incompetent ligaments and one with attenuated ligaments. The average post-operative KSS was 84 (range 73-94) points. Noinstabilities were detected and prosthetic survival was 100% at the end of the follow-up.Conclusions: We recommend using posterior-stabilized plus implants in deformities <20°, with sufficient collateral ligaments and no bone defects; constrained prosthesis in patients with greater deformity (>20°) and collateral ligaments with some degree of sufficiency (attenuated at the most); and rotating-hinge implants in knees with collateral or multidirectional ligament insufficiency, associated with recurvatum, significant bone defects or severe deformities in rheumatoid arthritis or with neuropathic origin.

• English

  Background:This paper presents the functional results and indication criteria for prostheses for total knee arthroplasty with more constraint than posterior stabilization more constraint than posterior-stabilized.Methods:Retrospective analysis of 43 TKA in 40 patients with an average follow up of 6.2 years. The preoperative diagnoses were valgus osteoarthritis in 38 cases and varus in 5. We classified the sufficiency of the collateral ligaments as sufficient, attenuated  or incompetent. We developed a classification system for the valgus Osteoarthritis, which related the type of knee with the selected prosthesis.Results:Posterior-stabilized plus implants were used in 28 cases, with an average alignment of 15.9°: 26 were valgus knees, 21 of which presented sufficient and 5 attenuated ligaments. Constrained prosthesis were used in 7 patients with an average valgus alignment of 21.6°, (2 with sufficient and 5 with attenuated ligaments.) Rotating-Hinge prosthesis were used in 8 patients, 5 with an average valgus alignment of 24.6 ° (3 of them associated to recurvatum), 4 with incompetent ligaments and one with attenuated ligaments. Conclusions:            We recommend using: Posterior-stabilized plus implants in deformities lower than 20°, with sufficient collateral ligaments and no bone defects; constrained prosthesis in patients with greater deformity (>20°) with collateral ligaments with some degree of sufficiency (attenuated at the most); and rotating-hinge implants in knees with collateral or multidirectional ligament insufficiency, associated with recurvatum, significant bone defects or severe deformities in rheumatoid arthritis or neuropathic origin.