CALCULATION AND CONTROL OF BIOMECHANICAL AXIS

CALCULATION AND CONTROL OF BIOMECHANICAL AXIS
OF THE LOWER LIMBS IN FRONTAL PLANE AT ITS CORRECTION 
ACCORDING TO ILIZAROV 
O.V. Klimov (Kurgan, Russia) 
The purpose of this study was development of applied technique of preoperative 
planning and control of the obtained treatment result at correction of shape of the lower 
extremities in transosseous osteosynthesis conditions considering possible lengthening of the 
lower limb extremity segments. This work is based on the treatment results of 80 orthopaedic 
cases from different nosological groups. The surgical leg shape correction by medical or 
esthetic indications was made in these groups. In some cases, the surgical leg shape 
correction was accompanied by lengthening of lower extrimity segments. Modelling of the 
axis of the lower extremities was performed by correction of femorotibial angle.
The examination of the orthopaedic status of the patients in the framework of this study 
indicated the dependence of the normal values of the femorotibial angle from the individual 
anthropometric indices. These indices are defined by the pelvis width and length of the lower 
extrimities. Based on obtained characteristics, we proposed the scheme of trigonometric 
constructions and calculation of correction parameters considering the amount of possible 
lengthening of femur and (or) tibia during treatment. We also offered esthetic clinical and 
biomechanical criteria to determine admissible amounts of the shape correction of the lower 
extremities. In general, the study indicated the multi-factor correlation and interdependence 
of anthropometric indicators in operative leg shape correction combined with lengthening. 
This includes pre-operative planning. The practical use of the work outlined in this 
instructional techniques assessment, calculation and control treatment results have shown 
their relevance and simplicity in the practical application. Analysis of treatment results 
showed that in the 88.75% of the cases (71 patients) compliance of the design and the 
clinical outcome of treatment was archieved and in almost 100% cases achieved results were 
in range between maximum and minimum values of correction parameters. The practical 
application of the methodical techniques of evaluation, calculations, and control of treatment 
results showed their adequacy and simplicity for practical application. 
Key words: leg shape correction, height increase, Ilizarov method, cosmetic orthopaedics, 
biomechanics of the lower extremities. 
Получено 4 августа 2013