A functional comparison of conventional knee–ankle–foot orthoses and a microprocessor-controlled leg orthosis system based on biomechanical parameters

2014 ◽  
Vol 40 (2) ◽  
pp. 277-286 ◽  
Author(s):  
Thomas Schmalz ◽  
Eva Pröbsting ◽  
Roland Auberger ◽  
Gordon Siewert
Keyword(s):  
Knee Flexion ◽  
Weight Bearing ◽  
Swing Phase ◽  
Flexion Angle ◽  
Foot Orthoses ◽  
Joint Moments ◽  
Level Walking ◽  
Stance Control ◽  
Ankle Foot Orthoses ◽  
Biomechanical Parameters

Background: The microprocessor-controlled leg orthosis C-Brace enables patients with paretic or paralysed lower limb muscles to use dampened knee flexion under weight-bearing and speed-adapted control of the swing phase. Objectives: The objective of the present study was to investigate the new technical functions of the C-Brace orthosis, based on biomechanical parameters. Study design: The study enrolled six patients. The C-Brace orthosis is compared with conventional leg orthoses (four stance control orthoses, two locked knee–ankle–foot orthoses) using biomechanical parameters of level walking, descending ramps and descending stairs. Methods: Ground reaction forces, joint moments and kinematic parameters were measured for level walking as well as ascending and descending ramps and stairs. Results: With the C-Brace, a nearly natural stance phase knee flexion was measured during level walking (mean value 11° ± 5.6°). The maximum swing phase knee flexion angle of the C-Brace approached the normal value of 65° more closely than the stance control orthoses (66° ± 8.5° vs 74° ± 6.4°). No significant differences in the joint moments were found between the C-Brace and stance control orthosis conditions. In contrast to the conventional orthoses, all patients were able to ambulate ramps and stairs using a step-over-step technique with C-Brace (flexion angle 64.6° ± 8.2° and 70.5° ± 12.4°). Conclusion: The results show that the functions of the C-Brace for situation-dependent knee flexion under weight bearing have been used by patients with a high level of confidence. Clinical relevance The functional benefits of the C-Brace in comparison with the conventional orthotic mechanisms could be demonstrated most clearly for descending ramps and stairs. The C-Brace orthosis is able to combine improved orthotic function with sustained orthotic safety.

scholarly journals The Effect of Stance Control Orthoses on Gait Characteristics and Energy Expenditure in Knee-Ankle-Foot Orthosis Users

2010 ◽  
Vol 34 (2) ◽  
pp. 206-215 ◽  
Author(s):  
Priya Chantal Davis ◽  
Timothy Michael Bach ◽  
Darren Mark Pereira
Keyword(s):  
Energy Expenditure ◽  
Knee Joint ◽  
Knee Flexion ◽  
Foot Orthoses ◽  
Gait Characteristics ◽  
Stance Control ◽  
Ankle Foot Orthoses ◽  
Locked Knee ◽  
Control Knee ◽  
Walking Velocity

Stance Control knee-ankle foot orthoses (SCO) differ from their traditional locked knee counterparts by allowing free knee flexion during swing while providing stability during stance. It is widely accepted that free knee flexion during swing normalizes gait and therefore improves walking speed and reduces the energy requirements of walking. Limited research has been carried out to evaluate the benefits of SCOs when compared to locked knee-ankle foot orthoses (KAFOs). The purpose of this study was to evaluate the effectiveness of SCOs used for patients with lower limb pathology. Energy expenditure and walking velocity were measured in 10 subjects using an orthosis incorporating a Horton Stance Control knee joint. A GAITRite walkway was used to measure temporospatial gait characteristics. A Cosmed K4b2 portable metabolic system was used to measure energy expenditure and heart rate during walking. Two conditions were tested: Walking with stance control active (stance control) and walking with the knee joint locked. Ten subjects completed the GAITRite testing; nine subjects completed the Cosmed testing. Walking velocity was significantly increased in the stance control condition ( p < 0.001). There was no difference in the energy cost of walking ( p = 0.515) or physiological cost index (PCI) ( p = 0.093) between conditions. This study supports previous evidence that stance control knee-ankle foot orthoses increase walking velocity compared to locked knee devices. Contrary to expectation, the stance control condition did not decrease energy expenditure during walking.

scholarly journals PERFORMANCE, PATIENT BENEFITS AND ACCEPTANCE OF A NEW GENERATION OF MICROPROCESSOR-CONTROLLED STANCE AND SWING CONTROL ORTHOSIS

2018 ◽  
Author(s):  
Nadine Wismer ◽  
OA Alexander Krebs ◽  
Frank Braatz ◽  
Thomas Schmalz ◽  
Andreas Kranzl ◽  
...  
Keyword(s):  
Knee Flexion ◽  
Weight Bearing ◽  
Swing Phase ◽  
Anatomic Structure ◽  
National Assembly ◽  
Ankle Foot Orthosis ◽  
Stance Control ◽  
Locked Knee ◽  
Physiological Values ◽  
New Generation

INTRODUCTION By enabling users to flex the orthotic leg during swing phase and safely lock it during stance phase, stance control orthosis (SCO) offers clear benefits compared to locked knee-ankle-foot-orthosis (KAFO)1. Since such orthoses do not offer dampened knee flexion in the weight-bearing condition, this represents a limitation in everyday activities such as ramp and stair descent. C-Brace, a microprocessor controlled stance and swing orthosis (SSCO), overcomes many of those problems. Maximum knee flexion angle in stance and swing phase during level walking are closer to physiological values with C-Brace compared to conventional KAFOs2. The patients are with C-Brace able to descend stairs and ramps reciprocally2. Furthermore, patients report of safer and easier ability to perform activities of daily living3. The main aim of next generation C-Brace is a reduction in size and an increase of adaptability to the patient’s anatomic structure. Due to technological changes, improvements especially for difficult ADLs (e.g. walking on uneven ground) are expected. Abstract PDF  Link: https://jps.library.utoronto.ca/index.php/cpoj/article/view/32020/24438 How to cite: Wismer N, Krebs A, Braatz F, Schmalz T, Kranzl A, Breuer C. PERFORMANCE, PATIENT BENEFITS AND ACCEPTANCE OF A NEW GENERATION OF MICROPROCESSOR-CONTROLLED STANCE AND SWING CONTROL ORTHOSIS. CANADIAN PROSTHETICS & ORTHOTICS JOURNAL, VOLUME 1, ISSUE 2, 2018; ABSTRACT, POSTER PRESENTATION AT THE AOPA’S 101ST NATIONAL ASSEMBLY, SEPT. 26-29, VANCOUVER, CANADA, 2018.DOI: https://doi.org/10.33137/cpoj.v1i2.32020 Abstracts were Peer-reviewed by the American Orthotic Prosthetic Association (AOPA) 101st National Assembly Scientific Committee.  http://www.aopanet.org/

scholarly journals Relationship between Quadriceps Tendon Young’s Modulus and Maximum Knee Flexion Angle in the Swing Phase of Gait in Patients with Severe Knee Osteoarthritis

Medicina ◽  
2020 ◽  
Vol 56 (9) ◽  
pp. 437
Author(s):  
Bungo Ebihara ◽  
Takashi Fukaya ◽  
Hirotaka Mutsuzaki
Keyword(s):  
Young’S Modulus ◽  
Gait Speed ◽  
Knee Flexion ◽  
Young's Modulus ◽  
Quadriceps Tendon ◽  
Swing Phase ◽  
Flexion Angle ◽  
Knee Flexion Angle ◽  
Knee Oa ◽  
Analysis System

Background and objectives: Decreased knee flexion in the swing phase of gait can be one of the causes of falls in severe knee osteoarthritis (OA). The quadriceps tendon is one of the causes of knee flexion limitation; however, it is unclear whether the stiffness of the quadriceps tendon affects the maximum knee flexion angle in the swing phase. The purpose of this study was to clarify the relationship between quadriceps tendon stiffness and maximum knee flexion angle in the swing phase of gait in patients with severe knee OA. Materials and Methods: This study was conducted from August 2018 to January 2020. Thirty patients with severe knee OA (median age 75.0 (interquartile range 67.5–76.0) years, Kellgren–Lawrence grade: 3 or 4) were evaluated. Quadriceps tendon stiffness was measured using Young’s modulus by ShearWave Elastography. The measurements were taken with the patient in the supine position with the knee bent at 60° in a relaxed state. A three-dimensional motion analysis system measured the maximum knee flexion angle in the swing phase. The measurements were taken at a self-selected gait speed. The motion analysis system also measured gait speed, step length, and cadence. Multiple regression analysis by the stepwise method was performed with maximum knee flexion angle in the swing phase as the dependent variable. Results: Multiple regression analysis identified quadriceps tendon Young’s modulus (standardized partial regression coefficients [β] = −0.410; p = 0.013) and gait speed (β = 0.433; p = 0.009) as independent variables for maximum knee flexion angle in the swing phase (adjusted coefficient of determination = 0.509; p < 0.001). Conclusions: Quadriceps tendon Young’s modulus is a predictor of the maximum knee flexion angle. Clinically, decreasing Young’s modulus may help to increase the maximum knee flexion angle in the swing phase in those with severe knee OA.

Effects of Ankle-Foot Orthoses for Children with Hemiplegia on Weight-Bearing and Functional Ability

2009 ◽  
Vol 21 (3) ◽  
pp. 225-234 ◽  
Author(s):  
Tara O’Reilly ◽  
Adrienne Hunt ◽  
Bronwyn Thomas ◽  
Lynne Harris ◽  
Joshua Burns
Keyword(s):  
Functional Ability ◽  
Weight Bearing ◽  
Foot Orthoses ◽  
Ankle Foot Orthoses

Investigating the Effect of Real-Time Center of Pressure (CoP) Feedback Training on the Swing Phase of Lower Limb Kinematics in Transfemoral Prostheses with SACH foot

2021 ◽  
Author(s):  
Ashutosh Tiwari ◽  
Abhijeet Kujur ◽  
Jyoti Kumar ◽  
Deepak Joshi
Keyword(s):  
Real Time ◽  
Lower Limb ◽  
Knee Flexion ◽  
Center Of Pressure ◽  
Feedback System ◽  
Swing Phase ◽  
Flexion Angle ◽  
Heel Strike ◽  
Knee Flexion Angle ◽  
Joint Angles

Abstract Transfemoral amputee often encounters reduced toe clearance resulting in trip-related falls. Swing phase joint angles have been shown to influence the toe clearance therefore, training intervention that targets shaping the swing phase joint angles can potentially enhance toe clearance. The focus of this study was to investigate the effect of the shift in the location of the center of pressure (CoP) during heel strike on modulation of the swing phase joint angles in able-bodied participants (n=6) and transfemoral amputees (n=3). We first developed a real-time CoP-based visual feedback system such that participants could shift the CoP during treadmill walking. Next, the kinematic data were collected during two different walking sessions- baseline (without feedback) and feedback (shifting the CoP anteriorly/posteriorly at heel strike to match the target CoP location). Primary swing phase joint angle adaptations were observed with feedback such that during the mid-swing phase, posterior CoP shift feedback significantly increases (p&lt;0.05) the average hip and knee flexion angle by 11.55 degrees and 11.86 degrees respectively in amputees, whereas a significant increase (p&lt;0.05) in ankle dorsiflexion, hip and knee flexion angle by 3.60 degrees, 3.22 degrees, and 1.27 degrees respectively compared to baseline was observed in able-bodied participants. Moreover, an opposite kinematic adaptation was seen during anterior CoP shift feedback. Overall, results confirm a direct correlation between the CoP shift and the modulation in the swing phase lower limb joint angles.

scholarly journals Forces and moments in knee–ankle–foot orthoses while walking on irregular surfaces: A case series study

2013 ◽  
Vol 38 (2) ◽  
pp. 104-113 ◽  
Author(s):  
Jan Andrysek ◽  
Susan Klejman ◽  
John Kooy
Keyword(s):  
Knee Flexion ◽  
Real Life ◽  
Case Series ◽  
Assistive Devices ◽  
Foot Orthoses ◽  
Irregular Surfaces ◽  
Case Series Study ◽  
Peak Knee ◽  
Ankle Foot Orthoses ◽  
Series Study

Background: Kinetic data provide important information about the mobility performance of individuals with lower limb impairments and their assistive devices; however, there is limited understanding of this in real-life environments. Objective: To evaluate the effect of real-life irregular surfaces on forces and moments in knee–ankle–foot orthoses. Methods: In this case series study, a load cell was used to measure the forces and moments at the knee joint of knee–ankle–foot orthoses of individuals with unilateral muscle weakness as a result of poliomyelitis while walking on different ground surfaces and at different speeds. Results: Significantly higher shear forces and external peak knee flexion moments were found when walking on irregular surfaces. In individual cases, certain irregular ground conditions elicited large increases in peak flexion moments (>50%) when compared to walking on smooth level ground. Forces and moments were significantly higher at faster walking speeds. Conclusions: Higher external peak knee flexion moments during the stance phase suggest that greater demands for support and stability are placed on individuals and their assistive devices when negotiating real-life ground surfaces. Clinical relevance This study demonstrates that walking on irregular surfaces alters the loads placed on knee–ankle–foot orthoses and that the requirements for knee stabilization increase. This has important clinical implications on the design, prescription, and use of such devices given the structural and functional demands placed on them.

scholarly journals Weight-Bearing Knee Flexion Angle Better Correlates with Patient-Reported Outcome Measures Than Non-Weight-Bearing Condition in Total Knee Arthroplasty: A Three-Dimensional Analysis Study

2021 ◽  
Author(s):  
Tomofumi Kage ◽  
Hiroshi Inui ◽  
Tetsuya Tomita ◽  
Takaharu Yamazaki ◽  
Shuji Taketomi ◽  
...  
Keyword(s):  
Knee Flexion ◽  
Weight Bearing ◽  
Three Dimensional ◽  
Patient Reported Outcome Measures ◽  
Flexion Angle ◽  
3D Analysis ◽  
Knee Flexion Angle ◽  
Angular Difference ◽  
Functional Activities ◽  
Patient Reported

Abstract Background: This study aims to elucidate and compare the relationship between the knee flexion angle and patient-reported outcome measures (PROM) in both non-weight-bearing (NWB) and weight-bearing (WB) conditions. Methods: This retrospective cohort study included 61 knees (47 patients) who underwent total knee arthroplasty. The knee flexion angle was measured by three conditions: NWB in manual goniometer, NWB in fluoroscopic three-dimensional (3D) analysis and WB in the fluoroscopic 3D analysis. The PROM was evaluated by postoperative 2011 Knee Society Score (2011 KSS) and Knee injury and Osteoarthritis Outcome Score (KOOS). Correlations between the knee flexion angle and PROM was analyzed using Spearman’s correlation coefficient. Additionally, whether the angular difference between NWB and WB correlated with the PROM or not was evaluated. Results: The NWB knee flexion angle in a goniometer, NWB in 3D analysis, and WB in 3D analysis were 124.6° ± 8.4°, 118.0° ± 10.5°, and 109.5° ± 13.3°, respectively. The angular difference was 8.5° ± 12.8°. No PROM correlation existed in NWB using a goniometer. Moreover, significant positive correlations in 2011 KSS symptoms (r = 0.35) and 2011 KSS functional activities (r = 0.27) were noted in NWB using 3D analysis. Significant positive correlations existed in 2011 KSS symptoms (r = 0.32), 2011 KSS functional activities (r = 0.57), KOOS pain (r = 0.37), KOOS activity of daily living (ADL; r = 0.45), KOOS sports (r = 0.42), and KOOS quality of life (r = 0.36) in WB using 3D analysis. Significant negative correlations were noted in 2011 KSS functional activities (r = −0.45), KOOS ADL (r = −0.30), and KOOS sports (r = −0.38) in angular difference. Conclusions: The WB knee flexion angle better correlated with PROM compared with NWB by evaluation of 3D analysis. The larger the angular difference existed between NWB and WB, the lower the PROM score.

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