J Knee Surg 2020; 33(01): 053-061
DOI: 10.1055/s-0038-1676564
Original Article
Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Effect of Tibial Component Alignment and Posterior Slope on Tibial Coverage in a Chinese Population: A Three-dimensional Anthropometric Study

Long Shao*
1  Department of Orthopaedic Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
,
Ting Wang*
1  Department of Orthopaedic Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
,
Junyi Liao
1  Department of Orthopaedic Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
,
Wei Xu
1  Department of Orthopaedic Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
,
Xi Liang
1  Department of Orthopaedic Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
,
Wei Huang
1  Department of Orthopaedic Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
› Institutsangaben
Funding None.
Weitere Informationen

Publikationsverlauf

24. Juli 2018

28. Oktober 2018

Publikationsdatum:
21. Dezember 2018 (online)

Abstract

The standard for rotational alignment and posterior slope of the tibial component in total knee arthroplasty remains controversial. This study aimed to evaluate the effect of tibial component alignment and posterior slope on tibial coverage. Computer tomographic scans of 101 tibial specimens were used to reconstruct three-dimensional tibia models. A virtual surgery was performed to generate a resection plane with different posterior slopes on the proximal tibia. Symmetrical and anatomical tibial components were placed aligning to the medial one-third of tibial tubercle (Insall) and the medial edge of patella tendon (Akagi), respectively. Differences in coverage and mismatch were evaluated and statistically compared across alignments, slope angles, and genders. The tibial coverage increased from 83.21 to 85.96% for Akagi's alignments and from 85.19 to 87.22% for Insall alignments along with the increasing of posterior slope from 0 to 7 degrees. Regardless of the prosthesis design, there was a significant difference between two rotational alignments as the Insall alignment was significantly higher in tibial coverage. With a slope of 7 degrees, more overhang along with less underhang anteromedially were found in males compared with females. The current anatomical tibial design has a tendency of overhang in the anteromedial zone which does not exist in the symmetrical design. The current tibial baseplate design has better tibial coverage when aligning to the medial third of tibial tuberosity with slopes of 5 and 7 degrees. Gender difference should be taken into account and given priority for prosthesis design.

* Long Shao and Ting Wang contributed equally to this work and should be considered co-first authors.


Supplementary Material