The AO Knee Expert Group who met a few years back - Professor Fujisawa is second from left in the front row. He published a paper in 1979 which led to the concept of the 'Fujisawa Point'.
Based on Professor Fujisawa's paper, Frank Noyes came up with the idea of a ‘Fujisawa position’ which was 67.5 percentage from medial to lateral on the tibial plateau, so on the medial side you have zero and going to the lateral side you are at 100, and the Fijisawa position is taken as that.
We are really beginning to tailor our osteotomies now, and with digital planning we can do this. There is a very nice paper from Andreas Imhoff’s group by Matthias Feucht, and this presented this approach of actually tailoring the degree of correction to the patient, which is our philosophy.
This is a video showing how a digital plan is to be made. There is no sound, but it shows the surgeon planning out initially the plots around the femur at the top and then around the knee and tibia, and it allows us to move on and do a ‘virtual osteotomy’ and really plan in great detail where we are going to correct to, and where the new weight-bearing line is going to be. It is this sort of software that has enabled us to get the accuracy that we can currently achieve.
Digital planning has transformed the whole discipline of osteotomy, but these advances always have to begin somewhere!
Front row left to right are:
In these X-rays we can see a pre-operative patient who is very bow-legged. The weight-bearing axis is at 20 percent from the medial side to the lateral side. We want to correct it to 55% - in the middle slide of the osteotomy - and what we have actually achieved is 53.4% and we are very close.
This paper from our own group explores the history of osteotomy from the days of Hippocrates to the modern era of digital planning. It shows how far we have travelled, but much of the progress has been in the last decade.