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In Vitro Application of a Wireless Sensor in Flexion-Extension Gap Balance of Unicompartmental Knee Arthroplasty
Published on: May 5, 2023
979
New method for acquiring the expected extension gap in total knee arthroplasty
Hitoshi Sekiya1, Kenzo Takatoku2, Yuji Kanaya2
1Department of Orthopaedic Surgery, Shin-Kaminokawa Hospital, 2360 Kaminokawa, Kawachi-gun, Tochigi, 3290611, Japan. hsekiya@jichi.ac.jp.
Summary
A new proximal tibial cutting method improves total knee arthroplasty (TKA) outcomes by achieving the desired tibial gap. This technique enhances surgical precision, leading to better implant fit and potentially better patient results in TKA procedures.
Area of Science:
- Orthopedic Surgery
- Biomedical Engineering
- Arthroplasty Research
Background:
- Achieving optimal soft-tissue balance is critical for successful total knee arthroplasty (TKA).
- Conventional gap techniques can sometimes fail to achieve the desired tibial gap, impacting implant fit and patient outcomes.
- Accurate tibial gap management is essential for proper alignment and function post-TKA.
Purpose of the Study:
- To introduce and evaluate a novel proximal tibial cutting technique designed to achieve the expected tibial gap during TKA.
- To assess the efficacy of this new method in facilitating the insertion of an appropriately sized tibial liner.
- To compare the precision of the new technique against conventional methods in managing the tibial gap.
Main Methods:
- A case-control study involving 128 patients undergoing medial pivot-type TKA for varus knee osteoarthritis.
- A 'pre-gap' measurement was taken using a trial femoral component under valgus stress before proximal tibial cutting in the experimental group (n=64).
- The primary outcome measure was Δgap, the difference between expected and final tibial liner thickness, compared between the pre-gap group and a control group (n=64) using conventional cutting.
Main Results:
- The pre-gap group achieved an ideal tibial cut (Δgap=0) in 82% of cases, compared to 61% in the control group.
- The frequency of significant outliers (Δgap ≥ 2 mm) was lower in the pre-gap group (4%) versus the control group (18%).
- The correct tibial liner size was selected more often in the pre-gap group, indicating improved gap prediction.
Conclusions:
- The developed proximal tibial cutting method, utilizing pre-gap measurement, is effective in achieving the target tibial gap during TKA.
- This technique helps avoid inadequate gaps in extension, contributing to more predictable surgical outcomes.
- The findings suggest this novel approach enhances precision in TKA surgery, potentially improving functional results.
