ACCURACY AND REPEATABILITY OF AXES FOR FEMORAL COMPONENT ROTATION IN TOTAL KNEE ARTHROPLASTY: A CADAVERIC STUDY

This study measured the three bony axes usually used for femoral component rotation in total knee arthroplasty and compared the accuracy and repeatability of different measurement techniques.Fresh cadaveric limbs (n=6) were used. Three observers (student, trainee and consultant) identified the posterior condylar (PCA), anteroposterior (AP) and the transepicondylar (TEA) axes, using a computer navigation system to record measurements. The AP axis was measured before and after being identified with an ink line. The TEA was measured by palpation of the epicondyles both before and after an incision was made in the medial and lateral gutters at the level of the epicondyles, allowing the index finger to be passed behind the gutters. In addition the true TEA was identified after dissection of all the soft tissues. Each measurement was repeated three times. For all axes and each observer the repeatability coefficient was calculated.The identification of the PCA was the most reliable (repeatability coefficient: 1....