Relationship between Tibial Baseplate Design and Rotational Alignment Landmarks in Primary Total Knee Arthroplasty

Abstract

This study evaluated the influence of modern tibial baseplate designs when using the anterior tibial cortex as a primary rotational landmark for the tibial baseplate in TKA. Eighty patients undergoing TKA were randomized in two groups. Group 1 included 25 females and 15 males receiving a posterior-stabilized (PS) symmetric tibial baseplate while Group 2 included 24 females and 16 males receiving a PS anatomical tibial component. Identical surgical technique, including the use of the surgical transepicondylar femoral axis (sTEA) and the anterior tibial cortex (“Curve-on-Curve”) as rotational alignment landmarks, was used. All patients underwent CT evaluation performed with the knee in full extension. Three observers independently measured the rotational alignment of the tibial component in relation to the sTEA. The rotational alignment of the symmetric baseplate showed an average external rotation of 1.3° (minimum 5°, maximum −1°): 91% of the knees showed 0 ± 3° with respect to the surgical sTEA, being internally rotated in 20%. The rotational alignment of the anatomical baseplate showed an average external rotation of 4.1° (minimum 0.4°, maximum 8.9°): only 47.5% of the knees showed 0 ± 3°, being externally rotated in 100%. The difference between the two groups was statistically significant. This study confirms the reliability of the “Curve-on-Curve” technique as an adequate rotational alignment anatomical landmark in TKA: the use of an asymmetric tibial baseplate might lead to external rotation of the tibial component when this technique is intraoperatively chosen.

The personalized Berger method is usable to solve the problem of tibial rotation

“…Our results are amongst the best, with similar inter- and intra-observer reliability compared to other authors; for this, we have the following explanations: the reference points were specified in a precise manner and all three of the examiners followed the same protocol [ 6 , 8 , 22 , 23 , 26 , 27 , 29 – 31 , 34 , 35 , 39 , 42 , 44 , 48 ].…”

“…The repeatability and reliability of the classic Berger method and its modifications were examined by several authors. Most of them mention good and excellent intra- and inter-observer intra-class correlation coefficients (ICC) [ 8 , 23 , 26 , 27 , 29 – 31 , 35 , 42 , 44 , 48 ].…”

Medial Pivot in Total Knee Arthroplasty: Literature Review and Our First Experience

“…At this point, the femoral component is fitted according to the femoral cuts, the anatomical tibial plateau is oriented following the medial third of the tibial tubercle, 16 and the MC insert trial is used evaluating the stability of the knee during the all range of motion (ROM) with the patella relocating on the femoral groove. When a wide ROM with a stable knee is restored, the final tibial insert is introduced.…”

Intraoperative load-sensing drives the level of constraint in primary total knee arthroplasty: Surgical technique and review of the literature

“…The rotational alignment of the Persona anatomical tibial component is set according to the medial third of the tibial tubercle. 26 When it is felt that both gaps are balanced using standard instrumentation and with the trial components in place, the CR VERASENSE tibial sensor is inserted (Fig. 2).…”