A new fixation material for open-wedge tibial osteotomy for genu varum.

Varus deformity of the knee is a determining factor in the development of osteoarthrosis of the medial compartment. Open wedge osteotomy corrects the deformity and has quickly become popular due to the fact that the surgical technique can be easily reproduced, it spares loss of bone tissue in the metaphysiary region, and it does not require muscle dissection, reducing the risk of lesion of the fibular nerve. The objective of this study was to evaluate the characteristics of a new fixation implant (Anthony-K plate - France Bloc S.A, CE n0499, ISO 9001, EN 46001), in terms of its clinical improvement, correction of the deformity, and slope alteration. Twenty adult patients with varus deformity were evaluated, and submitted to open wedge high tibial osteotomy using the Anthony plate, between October 2004 and November 2006. The varus deformity was corrected in all cases, and there was a significant increase in the Lysholm score. Correlation analysis has shown that the greater the preoperative varus deformity, the larger the opening wedge used. Also, the greater the initial posterior tibial slope, the larger the final posterior tibial slope (p=0.0168). There were no complications. The Anthony plate can be considered an alternative in the treatment of medial osteoarthrosis of the varus knee, enabling the correction of the deformity and improvement of the clinical picture. It occurs an increase in posterior tibial slope, similar to that observed with other fixation materials. More studies with the Anthony plate are necessary, after these encouraging results.