The axis-board: An alternative to the cable technique for intraoperative assessment of lower limb alignment

Abstract

Introduction:

Accurate intraoperative assessment of lower limb alignment is crucial for the treatment of long bone fractures, implantation of knee arthroplasties and correction of deformities.

Purpose:

The aim of this study is to present a new technique for the intraoperative analysis of the mechanical axis.

Methods:

The axis board is placed under the patient's lower limb. With the centre of the ankle and hip lying on the reference line we can assess the mechanical axis of the lower limb. This technique was used in 38 cases (19 high tibial osteotomies, 13 femoral fractures and 6 tibial fractures).

Results:

Comparing the intraoperative tibiofemoral angles and Mechanical Axis Deviations (MAD) with the results of the postoperative long standing radiographs we showed an accuracy of 1 ± 0.9° and 2.9 ± 2.6 mm respectively.

Conclusion:

The method is a simple and convenient option for intraoperative evaluation of the mechanical axis. However, for complex corrections we still recommend the use of navigation systems.