Sixu Zhou , Hanjun Kim , Jairo Maldonado-Contreras , Atli Örn Sverrisson , David Langlois , Kinsey Herrin , Aaron Young
{"title":"Biomechanical and energetic effects of knee flexion control during incline walking for users of the Power Knee","authors":"Sixu Zhou , Hanjun Kim , Jairo Maldonado-Contreras , Atli Örn Sverrisson , David Langlois , Kinsey Herrin , Aaron Young","doi":"10.1016/j.clinbiomech.2025.106499","DOIUrl":null,"url":null,"abstract":"<div><h3>Background</h3><div>Individuals with transfemoral amputation often report difficulty with ambulating on inclined surfaces. Conventional prosthetic control strategies typically apply a level walking controller in incline walking modes, which may not be biomechanically optimal. Able-bodied individuals modulate knee stance pre-flexion substantially during incline walking, which is absent in most prosthetic level walking controllers. However, the biomechanical effects of stance pre-flexion for users with robotic microprocessor-controlled knees are not well-explored during inclines.</div></div><div><h3>Methods</h3><div>In this study (<em>n</em> = 10), we investigated the joint kinematics/kinetics/power, biological joint level work and metabolic energy cost to evaluate the biomechanical effects of stance pre-flexion on a 7.5<sup>o</sup> incline walking using a commercially available robotic prosthetic knee, the Össur Power Knee, and a passive foot, the Össur Pro-Flex LP. We ran a Bradley-Terry model to rank user preferences on stance pre-flexion conditions.</div></div><div><h3>Findings</h3><div>We found that a 16.7 % reduction on the contralateral biological ankle joint positive work during stance phase when stance pre-flexion increased (<em>p</em> < 0.01). However, there was no significant difference in metabolic energy cost. Survey data revealed participants preferred higher stance pre-flexion angles (12<sup>o</sup> -18<sup>o</sup>) compared to lower angles (0<sup>o</sup> - 6<sup>o</sup>), indicating consistent preference towards increased stance pre-flexion on inclines.</div></div><div><h3>Interpretation</h3><div>Our results indicate that reduction in biological joint work associated with stance pre-flexion emphasizes the need to implement stance pre-flexion adjustments in prosthesis controllers, as opposed to using a level-walking controller.</div></div>","PeriodicalId":50992,"journal":{"name":"Clinical Biomechanics","volume":"124 ","pages":"Article 106499"},"PeriodicalIF":1.4000,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Clinical Biomechanics","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0268003325000725","RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"ENGINEERING, BIOMEDICAL","Score":null,"Total":0}
引用次数: 0
Abstract
Background
Individuals with transfemoral amputation often report difficulty with ambulating on inclined surfaces. Conventional prosthetic control strategies typically apply a level walking controller in incline walking modes, which may not be biomechanically optimal. Able-bodied individuals modulate knee stance pre-flexion substantially during incline walking, which is absent in most prosthetic level walking controllers. However, the biomechanical effects of stance pre-flexion for users with robotic microprocessor-controlled knees are not well-explored during inclines.
Methods
In this study (n = 10), we investigated the joint kinematics/kinetics/power, biological joint level work and metabolic energy cost to evaluate the biomechanical effects of stance pre-flexion on a 7.5o incline walking using a commercially available robotic prosthetic knee, the Össur Power Knee, and a passive foot, the Össur Pro-Flex LP. We ran a Bradley-Terry model to rank user preferences on stance pre-flexion conditions.
Findings
We found that a 16.7 % reduction on the contralateral biological ankle joint positive work during stance phase when stance pre-flexion increased (p < 0.01). However, there was no significant difference in metabolic energy cost. Survey data revealed participants preferred higher stance pre-flexion angles (12o -18o) compared to lower angles (0o - 6o), indicating consistent preference towards increased stance pre-flexion on inclines.
Interpretation
Our results indicate that reduction in biological joint work associated with stance pre-flexion emphasizes the need to implement stance pre-flexion adjustments in prosthesis controllers, as opposed to using a level-walking controller.
期刊介绍:
Clinical Biomechanics is an international multidisciplinary journal of biomechanics with a focus on medical and clinical applications of new knowledge in the field.
The science of biomechanics helps explain the causes of cell, tissue, organ and body system disorders, and supports clinicians in the diagnosis, prognosis and evaluation of treatment methods and technologies. Clinical Biomechanics aims to strengthen the links between laboratory and clinic by publishing cutting-edge biomechanics research which helps to explain the causes of injury and disease, and which provides evidence contributing to improved clinical management.
A rigorous peer review system is employed and every attempt is made to process and publish top-quality papers promptly.
Clinical Biomechanics explores all facets of body system, organ, tissue and cell biomechanics, with an emphasis on medical and clinical applications of the basic science aspects. The role of basic science is therefore recognized in a medical or clinical context. The readership of the journal closely reflects its multi-disciplinary contents, being a balance of scientists, engineers and clinicians.
The contents are in the form of research papers, brief reports, review papers and correspondence, whilst special interest issues and supplements are published from time to time.
Disciplines covered include biomechanics and mechanobiology at all scales, bioengineering and use of tissue engineering and biomaterials for clinical applications, biophysics, as well as biomechanical aspects of medical robotics, ergonomics, physical and occupational therapeutics and rehabilitation.