The Effects of Knee Orthosis with Two Degrees of Freedom Joint Design on Gait and Sit-to-Stand Task in Patients with Medial Knee Osteoarthritis

Objectives: Knee bracing as a conservative treatment option for patients with medial knee osteoarthritis (KOA) is of great interest to health practitioners and patients alike. Optimal orthotic knee joint structure is essential to achieve biomechanical and clinical effectiveness. Therefore, this study aimed to identify the effects of a knee orthosis with a new two-degrees-of-freedom (DOF) joint design on selected gait parameters and in a sit-to-stand task in patients with mild-to-moderate medial KOA. Methods: This study was conducted both at the Physical Medicine and Rehabilitation Clinic in Shahid Modarres Academic Hospital and the Biomechanical Laboratory of Rehabilitation Faculty of Iran University of medical Sciences in Tehran, Iran from September 2015 to October 2017. The gait performance of 16 patients was assessed without an orthosis, using a common one-DOF (DOF) knee orthosis and using the same knee orthosis with a two-DOF orthotic joint design. The interactive shearing force between limb and brace in the shell area during a sit-to-stand test was also identified. Repeated measures analysis of variance was used to analyse the data. Results: Compared with walking with no orthosis, both orthosis conditions reduced the external knee adduction moment significantly (P ≤0.05). A significant increase between the one-DOF and two-DOF conditions in terms of walking speed (P = 0.041 and P = 0.009, respectively) and stride length (P = 0.028 and P = 0.038, respectively) was observed. In a sit-to-stand test, wearing the orthosis significantly decreased knee transverse plane range of motion (P ≤0.05). There was a 41.31 ± 8.34 Newtons reduction in knee flexion constraint force. Conclusion: The two-DOF knee orthosis was more comfortable compared to the one-DOF knee orthosis during deep knee flexion. Otherwise, the one- DOF- and two-DOF-braces performed similarly. Keywords: Knee Osteoarthritis; Orthosis; Braces; Gait Analysis; Rotations; Kinematics; Kinetics; Patient Comfort.

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Design, Implementation and Testing of a Novel Prototype Orthotic Knee Joint with Two Degrees of Freedom in a Patient with Medial Knee Osteoarthritis

Sultan Qaboos University Medical Journal [SQUMJ] ◽

10.18295/squmj.2018.18.04.016 ◽

2019 ◽

Vol 18 (4) ◽

pp. 524

Author(s):

Siamak Aghajani-Fesharaki ◽

Farzam Farahmand ◽

Hassan Saeedi ◽

Ehsan Abdollahy

Keyword(s):

Knee Joint ◽

Knee Osteoarthritis ◽

Degrees Of Freedom ◽

Interaction Force ◽

Transverse Plane ◽

Materials Testing ◽

Keywords Knee ◽

Two Degrees Of Freedom ◽

Keywords Knee Joint ◽

The One

Knee braces are a conservative treatment option for patients with knee osteoarthritis (KOA). However, no commercially available orthotic knee joint currently reflects natural knee movements. A prototype orthotic knee joint with two degrees of freedom (DOF) in the sagittal and transverse planes was developed to more closely simulate the natural motion of the knee joint. The prototype was tested on a male subject with medial KOA during a sit-to-stand task. The efficacy of the transverse plane DOF was assessed by comparing the limb-orthosis interaction force when the transverse plane was locked to mimic a one-DOF setting versus when it was unlocked. Unlocking the transverse plane eliminated the 45-Newton shearing force produced with the one-DOF setting at wide angles of flexion. The two-DOF orthotic knee joint prototype demonstrated greater conformity to natural knee movements, allowing the wearer to better tolerate bracing-related difficulties. Keywords: Knee Joint; Knee Osteoarthritis; Orthotic Devices; Braces; Rotation; Movement; Materials Testing.

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Clinimetric properties of the one‐leg sit‐to‐stand test in examining unilateral lower limb muscle strength among young adults

International Journal of Clinical Practice ◽

10.1111/ijcp.13556 ◽

2020 ◽

Vol 74 (9) ◽

Author(s):

Surachart Thongchoomsin ◽

Sunee Bovonsunthonchai ◽

Leonard Joseph ◽

Samatchai Chamnongkich

Keyword(s):

Young Adults ◽

Muscle Strength ◽

Lower Limb ◽

Lower Limb Muscle ◽

Limb Muscle ◽

Stand Test ◽

Sit To Stand ◽

The One

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Biomechanics performance in 30-s chair stand test in patients with medial knee osteoarthritis

International Journal of Human Factors and Ergonomics ◽

10.1504/ijhfe.2019.10026995 ◽

2019 ◽

Vol 6 (4) ◽

pp. 319

Author(s):

Francisco Xará Leite ◽

Paulo Roriz ◽

Leandro Machado ◽

Adélio Vilaça ◽

Vitor Ferreira

Keyword(s):

Knee Osteoarthritis ◽

Medial Knee ◽

Chair Stand ◽

Stand Test ◽

Medial Knee Osteoarthritis ◽

Chair Stand Test

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Transient Growth Before Coupled-Mode Flutter

Journal of Applied Mechanics ◽

10.1115/1.1631591 ◽

2003 ◽

Vol 70 (6) ◽

pp. 894-901 ◽

Cited By ~ 14

Author(s):

P. J. Schmid ◽

E. de Langre

Keyword(s):

Degrees Of Freedom ◽

Mechanical Energy ◽

Linear Stability Theory ◽

Transient Growth ◽

Significant Discrepancy ◽

Two Degrees Of Freedom ◽

Coupled Mode ◽

Flow Induced Vibrations ◽

The One ◽

Analytical Approaches

Transient growth of energy is known to occur even in stable dynamical systems due to the non-normality of the underlying linear operator. This has been the object of growing attention in the field of hydrodynamic stability, where linearly stable flows may be found to be strongly nonlinearly unstable as a consequence of transient growth. We apply these concepts to the generic case of coupled-mode flutter, which is a mechanism with important applications in the field of fluid-structure interactions. Using numerical and analytical approaches on a simple system with two degrees-of-freedom and antisymmetric coupling we show that the energy of such a system may grow by a factor of more than 10, before the threshold of coupled-mode flutter is crossed. This growth is a simple consequence of the nonorthogonality of modes arising from the nonconservative forces. These general results are then applied to three cases in the field of flow-induced vibrations: (a) panel flutter (two-degrees-of-freedom model, as used by Dowell) (b) follower force (two-degrees-of-freedom model, as used by Bamberger) and (c) fluid-conveying pipes (two-degree-of-freedom model, as used by Benjamin and Pai¨doussis) for different mass ratios. For these three cases we show that the magnitude of transient growth of mechanical energy before the onset of coupled-mode flutter is substantial enough to cause a significant discrepancy between the apparent threshold of instability and the one predicted by linear stability theory.

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5 TIMES SIT-TO-STAND TEST PERFORMANCE IN DIFFERENT CATEGORY OF UNILATERAL AND BILATERAL KNEE OSTEOARTHRITIS PATIENTS

GFNPSS-International Journal of Multidisciplinary Research ◽

10.46376/ijmr/1.1.2020.15-25 ◽

2020 ◽

Vol 1 (1) ◽

pp. 15

Author(s):

Manoj kumar ◽

Dipti Padole ◽

Chaitany Patel ◽

Arjun Panchal ◽

Nisarg Raval

Keyword(s):

Knee Osteoarthritis ◽

Test Performance ◽

Stand Test ◽

Bilateral Knee ◽

Sit To Stand

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Decreased Balance Function in School-Aged Children with Behavioral Problems

Brain Sciences ◽

10.3390/brainsci12010117 ◽

2022 ◽

Vol 12 (1) ◽

pp. 117

Author(s):

Naomichi Matsunaga ◽

Tadashi Ito ◽

Yuji Ito ◽

Jun Mizusawa ◽

Yingzhi Gu ◽

...

Keyword(s):

Behavioral Problems ◽

Step Test ◽

Balance Function ◽

Test Results ◽

Emotional Symptoms ◽

Stand Test ◽

School Aged Children ◽

Sit To Stand ◽

The One ◽

Balance Functions

Children with behavioral problems have a high risk of impaired motor performance. However, the characteristics of balance functions and their associations with behavioral traits are unclear in this population. This study aimed to evaluate balance functions and their relationships with the degree of behavioral problems in school-aged children. A total of 209 children, aged 6–10 years, were divided into two groups, those with and those without behavioral problems, using the Strengths and Difficulties Questionnaire (SDQ). Physical assessments included the one-leg standing test (OLST), the two-step test, and the five-times-sit-to-stand test. We compared the data between groups and assessed for correlations in terms of total difficulties and the SDQ subscale scores. Children with behavioral problems showed significantly reduced the OLST results (p < 0.001) and the two-step test results (p = 0.008). The five-times-sit-to-stand test results did not show significant differences between groups. The OLST results were significantly correlated with emotional symptoms (r = −0.22, p < 0.001), hyperactivity/inattention (r = −0.29, p < 0.001), peer relationship problems (r = −0.22, p < 0.001), and total difficulties (r = −0.32, p < 0.001). Meanwhile, the two-step test results showed no significant correlation with the SDQ scores. Children with behavioral problems have poor balance function, thereby increasing the risk for instability. This suggests that the balance function of children with behavioral problems needs to be considered.

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