Development of biomechanical database for osteotomy around the knee

2024 Fiscal Year Final Research Report

• Project/Area Number: 21K16672
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 56020:Orthopedics-related
• Research Institution: Hokkaido University
• Principal Investigator: Iwasaki Koji 北海道大学, 医学研究院, 特任助教 (40771895)
• Project Period (FY): 2021-04-01 – 2025-03-31
• Keywords: 変形性膝関節症 / 膝周囲骨切り術 / バイオメカニクス / 加速度 / 動作解析

Outline of Final Research Achievements

Based on data from patients who underwent three-dimensional gait analysis, we developed a novel parameter(Pelvis-Knee-Ankle angle (PKA)), which demonstrated a stronger correlation with KAM and PROMs before and after open-wedge high tibial osteotomy (OWHTO), compared to HKA. PKA may serve as a biomechanical index for osteotomy around the knee based on load distribution. Additionally, using CT-osteoabsorptiometry, we analyzed regions of high subchondral bone density and found that patients showing an increase in the high-density area in the lateral-most part of the medial compartment, where mechanical stress is predicted to decrease postoperatively, shared a common feature of having MPTA of 94° or greater. These findings provide biomechanical evidence that overcorrection on the tibial side alone may lead to suboptimal surgical outcomes.

Free Research Field

Orthopedic surgery

Academic Significance and Societal Importance of the Research Achievements

膝周囲骨切り術前後の3次元動作解析、加速度解析データ、CT、MRI画像、及び患者立脚型評価のデータを集積を行った。膝周囲骨切り術は下肢アライメントを矯正することで、荷重分布を変化させることで、除痛、機能改善を図る術式であるが、これまで膝荷重分布を基にした膝周囲骨切り術の指標は明らかになっていなかった。今回開発したPKAはOWHTO術後のKAMとの相関が高く、これを発展させることで、膝周囲骨切り術の治療メカニズム、つまり患者の膝の荷重分布に基づいた膝周囲骨切り術の手術を行うことで、治療成績の向上につながる可能性がある。