Restoration of the Mechanical Axis in Total Knee Artrhoplasty Using Patient-Matched Technology Cutting Blocks. A Retrospective Study of 132 Cases

Document Type : RESEARCH PAPER


1 Minimal Invasive Hip and Knee Fellow, Sky Ridge Medical Center, 10101 Ridgegate, Lone Tree, Colorado, USA

2 Orthopedic and Trauma Surgeon, Sky Ridge Medical Center, 10101 Ridgegate, Lone Tree, Colorado, USA


Background: The aim of this study is to evaluate the accuracy of bone cuts and the resultant alignment, using the
MyKnee patient specific cutting blocks.
Methods: We retrospectively reviewed 132 patients undergoing primary TKR for osteoarthritis by one single surgeon.
The operative time, the preoperative Hip-Knee-Ankle (HKA) axis based on the CT-scan, the postoperative HKA axis
based on long axis standing x-rays, the planned and the actual size of the femoral and the tibial components, and the
number of the recuts which has been made intraoperative were measured.
Results: The average preoperative HKA axis was 177.50 (range 163.50 to 1940), whereas the average postoperative
HKA axis was 179.40 (range 177.10 to 182.70). No outliers were reported in the study (0%). Intraoperatively, 4 femoral
components (3.03%), and 7 tibial components (5.30%) applied to the patients were different than the planned size.
There was no need of recuts in any of our cases intraoperatively.
Conclusion: The MyKnee system evaluated in this study was shown to be remarkable reliable in the coronal plane
alignment, and the prediction of the component size. However, further studies are needed to determine whether there
are any clinically important improvements in outcomes or patient satisfaction when using patient-specific cutting blocks
for TKA.


Main Subjects

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