LIVRE JDG 2010

INTRODUCTION

The change in leg length after correcting the

deformity of the leg axis has been discussed

previously but the existing articles refer to cor-

rections after osteotomy [1-4]. We also per-

form a correction of the axis if needed while

performing a TKA. How is the change in leg

length after this procedure? How much leng-

thening is due to correction of the axis [5] and

how much is due to implantation of the pros-

thesis? In the following pilot-study we tried to

find a method which allows us to measure the

lengthening in AP long-leg weight-bearing

radiographs pre-and postoperative [6] and to

also compare these measurements with results

calculated from the difference between the

femoral-tibial mechanical angle (AFTm) pre

and postoperative. The AFTm is the angle bet-

ween the mechanical femoral axis and the

mechanical tibial axis measured on the medial

side of the knee. It will show us the varus or

valgus deformity of the leg (fig. 1).

CHANGES IN LENGTHAFTER TKA:

ACCURACY OFAPREDICTIVE METHOD

J. BRUDERER, S. LUSTIG, G. DEMEY, E. SERVIEN, PH. NEYRET

Fig. 1 : Measurements performed on every

preoperative and postoperative radiograph.