Computer-assisted techniques in Total Knee Arthroplasty

Computer navigation systems fall broadly into two categories. Image-based, which rely on the data acquired from pre- or intra-operative imaging from modalities such as CT or fluoroscopy; and image-free, which rely on the acquisition of certain specific anatomical points to recreate a patient-specific model of the area of interest. The essence of image-free systems is that they require the intra-operative registration of certain key anatomical points which determine the mechanical alignment of the tibia, the femur and the lower limb, and hence define the site of the bony cuts required for implant placement. Computer-assisted navigation has been reported to improve the accuracy and reproducibility of tibial and femoral component alignment in total knee arthroplasty. Potential disadvantages of the technique include increased operative time, and cost.