Skip to main content

ORIGINAL RESEARCH article

Front. Bioeng. Biotechnol.
Sec. Biomechanics
Volume 12 - 2024 | doi: 10.3389/fbioe.2024.1439616

Design and Evaluation of a Wedge-shaped Adaptive Knee Orthosis for the Human Lower Limbs

Provisionally accepted
Xin Zhou Xin Zhou 1Xiaoli Liu Xiaoli Liu 2*Jiaxin Hao Jiaxin Hao 1*Yu Liu Yu Liu 3*
  • 1 Xi'an University of Technology, Xi'an, China
  • 2 Xi'an Jiaotong University, Xi'an, China
  • 3 Xi'an Aeronautical University, Xi'an, Shaanxi, China

The final, formatted version of the article will be published soon.

    The incidence of knee osteoarthritis (KOA) is moderately correlated with age and body weight and increases with life span and weight gain, associated with tearing and wearing the knee joints. KOA can adjust the force through the human lower limbs, redistribute the load of the knee joint, reduce the pain, and restore mobility when the arthritis changes are mild. However, most of the existing knee orthosis cannot be adjusted adaptively according to the needs of patients. This study establishes a biomechanical model of the knee joint to analyze the medial and lateral forces acting on the joint. The new adjustable knee orthosis is designed. It applies the principle of four-point bending to apply pressure to both sides of the knee joint, thereby adjusting the varus angle and modifying the medial and lateral forces on the knee joint. Through structural optimization, the prototype of the knee orthosis weighs only 324g. Utilizing three-dimensional scanning technology, discrete point cloud data of the leg surface is obtained, reconstructed, and processed to create a 3D model of the human leg surface. The design ensures a close fit to the human leg surface, offering comfortable wear. A pressure sensing film system is employed to build a pressure sensing test system, where the knee orthosis is worn on a prosthesis for pressure testing to evaluate its ability to adjust knee joint forces. The pressure test results demonstrate that the knee orthosis can stably provide an adjustment angle of 0-7° and sustain a maximum force of 10N on both sides of the knee joint over extended periods. A self-developed 8-channel plantar pressure sensing insole is calibrated against commercial plantar pressure sensors. Human wear tests on 15 subjects show that during the operation of the knee orthosis, it significantly adjusts plantar pressures, reducing lateral foot pressures by 22% overall, with more pronounced corrective effects observed in lighter participants.

    Keywords: KOA, Knee Joint, mechanical design, knee orthosis, Pressure test

    Received: 28 May 2024; Accepted: 15 Aug 2024.

    Copyright: © 2024 Zhou, Liu, Hao and Liu. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

    * Correspondence:
    Xiaoli Liu, Xi'an Jiaotong University, Xi'an, 710049, China
    Jiaxin Hao, Xi'an University of Technology, Xi'an, China
    Yu Liu, Xi'an Aeronautical University, Xi'an, 710077, Shaanxi, China

    Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.