Artroplastia total de rodilla en genu valgo severo: Seguimiento de 5 a 14 años / Total knee arthroplasty in severe genu valgum. Five to 14 years follow-up

RESUMEN

Introducción: El deseje en valgo es una deformidad compleja, con alteracion osea y de partes blandas. Se han descrito numerosas tecnicas quirurgicas que detallan la secuencia de liberacion de las estructuras posterolaterales y la necesidad de utilizar implantes constrenidos. El reemplazo total de rodilla para el genu valgo es un desafio para el ortopedista. Los objetivos fueron evaluar nuestros resultados en el tratamiento quirurgico del genu valgo severo y detallar la tecnica quirurgica empleada. Materiales y Métodos: Se establecio una clasificacion clinico-radiologica y se discriminaron los casos con genu valgo severo. Se evaluaron 42 reemplazos totales de rodilla en 39 pacientes (seguimiento promedio 9.2 anos). Se utilizo el Knee Society Score como parametro de evaluacion clinica. Para la evaluacion radiografica, se conto con la radiografia de mejor calidad del ultimo control. El analisis de supervivencia contemplo la necesidad de revision por cualquier causa y por falla mecanica. Resultados: El Knee Society Score fue, en promedio, de 83,3, con franca mejoria en los parametros dolor y rango de movilidad. Se utilizaron implantes constrenidos en el 16,7% de los casos. El angulo posoperatorio promedio fue de 5,9°. Hubo dos revisiones, con una supervivencia protesica por falla mecanica del 97,6%. No hubo revisiones por causa infecciosa. Conclusiones: Se requiere de un minucioso examen fisico y radiografias preoperatorias. La decision de utilizar implante constrenido se toma durante la cirugia. Es importante la apropiada liberacion de partes blandas. Al margen de la tecnica quirurgica empleada, el requerimiento de protesis constrenida es bajo. Recomendamos nuestra tecnica, pues se trata de un procedimiento poco demandante con resultados alentadores a mediano y largo plazo. Nivel de Evidencia IV

ABSTRACT

Introduction: Valgus malalignment is a complex, multiplanar deformity characterized by bone alterations and soft-tissue abnormalities. Several surgical techniques have been described for valgus knee, and the sequence of tight lateral structure release and the need of constrained prosthesis were addressed. Total knee arthroplasty in valgus deformity remains a surgical challenge for orthopaedic surgeons. The objectives of the study were to evaluate our mid- and long-term results in the surgical treatment of severe valgus disease, and to describe the applied surgical technique. Methods: A clinical-radiological classification was developed, and patients treated for severe genu valgum were discriminated. We retrospectively evaluated 42 total knee arthroplasties in 39 patients, with an average follow-up of 9.2 years. Knee Society Score was used for clinical evaluation, and the last control best quality radiograph was considered for radiographic evaluation. Survival analysis contemplated the need for revision for any reason and for mechanical failure. Results: Postoperative average Knee Society Score was 83.3, with marked improvement in pain and range of motion parameters. Constrained implants were used in 16.7% of cases. Postoperative alignment was on average 5.9°. Two patients underwent revision surgery, having achieved a prosthetic survival for mechanical failure of 97.6%. We did not have any revision due to infection. Conclusions: A meticulous physical examination and proper preoperative radiographs are mandatory. The decision to use a constrained device is taken during surgery. Appropriate soft-tissue release is extremely important. Despite the surgical technique, the use of a constrained prosthesis is limited. We recommend our technique as a low-demanding procedure, with encouraging mid- and long-term results. Level of Evidence IV