Malpositioned axis
Common causes for pains in the knee are misalignments of the leg axis. Thus, the leg axis of particularly middle-aged people has to be carefully monitored.So-called knock knees or bandy legs lead to a consistently strong load of the meniscus and cartilage on the out- or inside of the knee. In the course of time this leads to an increased wear of the cartilage and injuries of the meniscus.Via x-rays of the whole leg while standing up the location and extent of the malalignment has to be recorded first of all.An additional MRT shows existing tears of the menisci and damages of the cartilage.Now, one can decide whether, how and where a surgical realignment is possible and makes sense.The realignment of the lower leg in case of bandy legs is most commonly performed.
One possibility of correction is the high tibial osteotomy (HTO) via the so-called opening wedge technique.
That means, that the lower leg bone is sawn and flipped open just below the knee. This way a hinge remains on the outside and the side flipped open is stabilized with a screwed-on titanium plate. For years the Tomofixsystem of the Fa. Synthes has proved particularly reliable. .
This procedure is much gentler and more exact than the closing wedge technique. Another advantage is that damages to the nerves appear less frequently, and furthermore the patients can mostly load again faster than patients having been operated with a different method. Long images of the leg axis are necessary for the exact determination of the axis misalignment and for the planning of the repositioning operation (=corrective osteotomy).