Determining the rotational alignment of the tibial component at total knee replacement

Abstract

We prospectively assessed the benefits of using either a range-of-movement technique or an anatomical landmark method to determine the rotational alignment of the tibial component during total knee replacement. We analysed the cut proximal tibia intraoperatively, determining anteroposterior axes by the range-of-movement technique and comparing them with the anatomical anteroposterior axis. We found that the range-of-movement technique tended to leave the tibial component more internally rotated than when anatomical landmarks were used. In addition, it gave widely variable results (mean 7.5 degrees ; 2 degrees to 17 degrees ), determined to some extent by which posterior reference point was used. Because of the wide variability and the possibilities for error, we consider that it is inappropriate to use the range-of-movement technique as the sole method of determining alignment of the tibial component during total knee replacement.

Is There a Gold Standard for TKA Tibial Component Rotational Alignment?

“…Currently, many anatomic landmarks are used to align the tibial component, including the projected femoral TEA [1,2,20,24], medial border of the tibial tubercle [17,18,22,47], medial 1/3 of the tibial tubercle [17,20,47], PCL attachment [1,2,23,47], transverse axis of the tibia [18,20,47], posterior condylar line of the tibia [18,20,23], midsulcus of the tibial spine [17], malleolar axis [1,18], patellar tendon [1,2,23,24], and axis of the second metatarsal [1]. This lack of a gold standard for tibial component alignment, combined with the difficulty in identifying anatomic landmarks during surgery and variations in anatomy between knees, may lead to variations in the surgeons' ability to locate tibial component alignment axes as large as 44°internal rotation to 46°external rotation [47].…”

Rotational Position of Femoral and Tibial Components in TKA Using the Femoral Transepicondylar Axis

“…Comparative studies [7] demonstrate the difficulties in achieving the desired rotation, relative to the TEA, typically showing outliers with abnormal external or internal rotation. Recently, Ikeuchi et al [13] reported a greater likelihood of tibial component internal rotation when using the selfaligning method. A rotational mismatch with TEA of more than 10°was found by Uehara et al [24] using different methods on postoperative computed tomography (CT) scans in 12% of the cases.…”

Biomechanical effects of total knee arthroplasty component malrotation: A computational simulation

“…[9][10][11] Siston et al 11 found rotational alignment errors ranging from 138 internal rotation to 168 external rotation. Errors can often occur in tibial component rotational alignment in the transverse plane, [12][13][14] ranging from 448 internal rotation to 468 external rotation. 14 The large variability may be due to the fact that small linear errors in identifying anatomic landmarks translate into large rotational errors.…”