scholarly journals Design Evaluation of a Novel Multicompartment Unloader Knee Brace

2019 ◽  
Vol 142 (1) ◽  
Author(s):  
Aleksandra R. Budarick ◽  
Bradley E. MacKeil ◽  
Stephen Fitzgerald ◽  
Christopher D. Cowper-Smith
Keyword(s):  
Weight Loss ◽  
Knee Joint ◽  
Weight Bearing ◽  
Knee Extension ◽  
Force Output ◽  
Knee Brace ◽  
Knee Oa ◽  
Joint Forces ◽  
Knee Joint Surgery ◽  
Knee Braces

Abstract Knee osteoarthritis (OA) is a significant problem in the aging population, causing pain, impaired mobility, and decreased quality of life. Conservative treatment methods are necessary to reduce rapidly increasing rates of knee joint surgery. Recommended strategies include weight loss and knee bracing to unload knee joint forces. Although weight loss can be beneficial for joint unloading, knee OA patients often find it difficult to lose weight or begin exercise due to knee pain, and not all patients are overweight. Unicompartment offloader knee braces can redistribute joint forces away from one tibiofemoral (TF) compartment; however, <5% of patients have unicompartmental tibiofemoral osteoarthritis (TFOA), while patients with isolated patellofemoral or multicompartmental OA are much more common. By absorbing body weight (BW) and assisting the knee extension moment using a spring-loaded hinge, sufficiently powerful knee-extension-assist (KEA) braces could be useful for unloading the whole knee. This paper (1) describes the design of a spring-loaded tricompartment unloader (TCU) knee brace intended to provide unloading in all three compartments of the knee while weight-bearing, (2) measures and compares the force output of the TCU against the only published and commercially available KEA brace, and (3) calculates the static unloading capacity of each device. The TCU and KEA braces delivered maximum assistive moments equivalent to reducing BW by approximately 45 and 6 lbs, respectively. The paper concludes that sufficiently powerful spring-loaded knee braces show promise in a new class of multicompartment unloader knee orthoses, capable of providing a clinically meaningful unloading effect across all three knee compartments.

Estimation of In-Vivo Quadriceps Forces of the Knee: A Combined In-Vivo Patellofemoral Joint Kinematics Measurement and Finite Element Prediction

2011 ◽  
Author(s):  
Koichi Kobayashi ◽  
Guoan Li
Keyword(s):  
Knee Joint ◽  
Load Transfer ◽  
Weight Bearing ◽  
Knee Oa ◽  
Moment Arms ◽  
Joint Reaction Forces ◽  
Joint Contact ◽  
Reaction Forces ◽  
Knee Pathology

The load transfer mechanics across the patellofemoral (PF) joint during weight-bearing conditions is important for treatment of the knee pathology, such as knee OA, ACL deficiency as well as TKA. Many studies have characterized the PF joint reaction forces using equilibriums of the quadriceps and ground reaction forces at the knee joint [1,2,3]. However, this simplification does not consider other muscle function as well as 3D knee joint contact location when calculate moment arms of the involved forces.

scholarly journals Effects of a Single Session of Floss Band Intervention on Flexibility of Thigh, Knee Joint Proprioception, Muscle Force Output, and Dynamic Balance in Young Adults

2021 ◽  
Vol 11 (24) ◽  
pp. 12052
Author(s):  
Nai-Jen Chang ◽  
Wei-Chun Hung ◽  
Chia-Lun Lee ◽  
Wen-Dien Chang ◽  
Bo-Han Wu
Keyword(s):  
Young Adults ◽  
Knee Joint ◽  
Muscle Force ◽  
Dynamic Balance ◽  
Quadriceps Muscle ◽  
Knee Extension ◽  
Force Output ◽  
Significant Difference ◽  
Hamstring Flexibility ◽  
Knee Muscle

The floss band (FB) has been correlated with increases in the joint range of motion (ROM). However, the literature on FB effectiveness in knee joint ROM and athletic performance remains sparse. This study investigated the effects of FB on the flexibility of the quadriceps and hamstrings, knee joint proprioception, muscle force output, and dynamic balance in men. Thirty recreationally active men without musculoskeletal disorders were randomized to receive FB (Lime Green; Sanctband flossband) and elastic bandage (EB) intervention on the dominant knee joint. Participants received two interventions on two occasions with 2 days of rest between interventions. The primary outcome was the flexibility of the quadriceps and hamstrings; the secondary outcomes were knee proprioception (joint reposition angle error), knee muscle force output, and dynamic balance. Preintervention and postintervention (immediately following band removal and 20 min later) measurements were obtained. After FB intervention, hamstring flexibility (immediately: p < 0.001; 20 min later: p < 0.001) and quadriceps flexibility (immediately: p < 0.001; 20 min later: p < 0.001), quadriceps muscle force output (immediately: p = 0.007; 20 min later: p < 0.001), and dynamic balance (both immediately and 20 min later, p < 0.001) were significantly improved. Compared with EB intervention, FB intervention significantly improved knee extension ROM (immediately and 20 min later, both p < 0.001), knee flexion ROM (immediately, p = 0.01; 20 min later, p = 0.03), hamstrings muscle force output (20 min later, p = 0.022) and dynamic balance (immediately, p = 0.016; 20 min later, p = 0.004). Regarding proprioception, no significant difference among time points and conditions was observed. In conclusion, FB intervention can significantly improve the flexibility of the quadriceps and hamstrings, quadriceps muscle force output, and dynamic balance without impeding knee proprioception. Physiotherapists or athletic professionals may consider FB intervention as a potential tool as a warmup to enhance the flexibility of the quadriceps and hamstrings, quadriceps muscle force output, and dynamic balance in young adults.

Effects of Prophylactic Knee Bracing on Lower Limb Kinematics, Kinetics, and Energetics During Double-Leg Drop Landing at 2 Heights

2016 ◽  
Vol 44 (7) ◽  
pp. 1753-1761 ◽  
Author(s):  
Katie A. Ewing ◽  
Rezaul K. Begg ◽  
Mary P. Galea ◽  
Peter V.S. Lee
Keyword(s):  
Knee Flexion ◽  
Knee Extension ◽  
Flexion Angle ◽  
Initial Contact ◽  
Knee Brace ◽  
Acl Injuries ◽  
Negative Power ◽  
Peak Knee ◽  
Knee Braces ◽  
Biomechanical Factors

Background: Anterior cruciate ligament (ACL) injuries commonly occur during landing maneuvers. Prophylactic knee braces were introduced to reduce the risk of ACL injuries, but their effectiveness is debated. Hypotheses: We hypothesized that bracing would improve biomechanical factors previously related to the risk of ACL injuries, such as increased hip and knee flexion angles at initial contact and at peak vertical ground-reaction force (GRF), increased ankle plantar flexion angles at initial contact, decreased peak GRFs, and decreased peak knee extension moment. We also hypothesized that bracing would increase the negative power and work of the hip joint and would decrease the negative power and work of the knee and ankle joints. Study Design: Controlled laboratory study. Methods: Three-dimensional motion and force plate data were collected from 8 female and 7 male recreational athletes performing double-leg drop landings from 0.30 m and 0.60 m with and without a prophylactic knee brace. GRFs, joint angles, moments, power, and work were calculated for each athlete with and without a knee brace. Results: Prophylactic knee bracing increased the hip flexion angle at peak GRF by 5.56° ( P < .001), knee flexion angle at peak GRF by 4.75° ( P = .001), and peak hip extension moment by 0.44 N·m/kg ( P < .001). Bracing also increased the peak hip negative power by 4.89 W/kg ( P = .002) and hip negative work by 0.14 J/kg ( P = .001) but did not result in significant differences in the energetics of the knee and ankle. No differences in peak GRFs and peak knee extension moment were observed with bracing. Conclusion: The application of a prophylactic knee brace resulted in improvements in important biomechanical factors associated with the risk of ACL injuries. Clinical Relevance: Prophylactic knee braces may help reduce the risk of noncontact knee injuries in recreational and professional athletes while playing sports. Further studies should investigate different types of prophylactic knee braces in conjunction with existing training interventions so that the sports medicine community can better assess the effectiveness of prophylactic knee bracing.

scholarly journals Tibial Condyle Valgus Osteotomy for Ipsilateral Knee Osteoarthritis after Hip Arthrodesis

2021 ◽  
Vol 2021 ◽  
pp. 1-5
Author(s):  
Daisuke Fukuhara ◽  
Hiroaki Inoue ◽  
Shuji Nakagawa ◽  
Yuji Arai ◽  
Kenji Takahashi
Keyword(s):  
Knee Joint ◽  
Knee Osteoarthritis ◽  
Mechanical Load ◽  
Weight Bearing ◽  
Valgus Osteotomy ◽  
Hip Arthrodesis ◽  
Knee Oa ◽  
Early Loosening ◽  
Tibial Condyle ◽  
End Stage

We report a case of tibial condylar valgus osteotomy (TCVO) for ipsilateral knee osteoarthritis (OA) after hip arthrodesis. A 58-year-old woman developed right purulent hip arthritis at one month of age and underwent right hip fusion at 16 years old. She visited our department at the age of 57 because her right knee joint pain worsened. The range of motion for her right knee was 80° and -5° of flexion and extension, respectively, and she experienced medial weight-bearing pain. A plain X-ray image showed that the right knee joint had end-stage knee OA with a bone defect inside the tibia, and the tibial plateau shape was the pagoda type. There was a marked instability in her right knee with a valgus of 9° and varus of 7° on stress photography. She underwent TCVO on her right knee and was allowed full load four weeks after surgery. Computed tomography imaging showed bone union nine months after surgery. Two years after the operation, there was no correction loss, and she could walk independently without pain. In general, total knee arthroplasty (TKA) is indicated for end-stage knee OA; however, there are problems, such as early loosening due to the increased mechanical load on the knee after hip OA. In this case, since a good course was obtained, TCVO is considered a treatment option for terminal knee OA after hip arthrodesis.

Investigating the Ability of Knee OA Patients to Maintain Targeted Knee Flexion Angles for Weight Bearing MRI

2011 ◽  
Author(s):  
Venkata Gade ◽  
Jerome Allen ◽  
Jeffrey L. Cole ◽  
Peter J. Barrance
Keyword(s):  
Knee Joint ◽  
Precise Measurement ◽  
Signal To Noise Ratio ◽  
Weight Bearing ◽  
Mr Images ◽  
Knee Oa ◽  
Symptomatic Knee ◽  
Measurement Tools ◽  
The Us ◽  
Common Clinical Presentation

Knee osteoarthritis (OA) is the most common clinical presentation of osteoarthritis, and has been estimated to affect 12–16% of the population older than 60 years in the US [1]. A biomechanical risk factor that has been linked to knee OA is the changes in the local loading and the contact area between the cartilage surfaces [2]. Investigation of such factors requires precise measurement tools to determine knee joint positioning and contact areas. Clinically, MR images of the knee are most frequently acquired in the supine position; such images are not representative of the loading conditions experienced functionally in the weight bearing knee joint. With the advent of vertically open MRI (e.g. Upright MRI, Fonar Corporation, Melville, NY), it is now possible to scan the knee in fully upright weight bearing conditions representing truly functional positions. To measure sensitive variables such as joint positioning and cartilage contact, it is important to minimize subject movement in order to obtain high quality images. In MRI, increased scan times allow for data of improved signal to noise ratio and resolution; however, long scanning durations without subject movement are not feasible, particularly in individuals with symptomatic knee OA.

Effect of verbal encouragement on quadriceps and knee joint function during three sets of knee extension exercise

2020 ◽  
pp. 1-7
Author(s):  
Hyunwook Lee ◽  
Jaeyoon Shin ◽  
Daeho Kim ◽  
Jihong Park
Keyword(s):  
Knee Joint ◽  
Knee Flexion ◽  
Knee Extension ◽  
Quadriceps Strength ◽  
Contributing Factors ◽  
Force Output ◽  
Joint Function ◽  
Central Activation ◽  
Verbal Encouragement ◽  
Knee Extension Exercise

BACKGROUND: Although the common practice of verbal encouragement is scientifically supported, its effect on the maintenance of force output in fatiguing exertions is unknown. OBJECTIVE: To examine the effects of verbal encouragement on exercise-induced quadriceps and knee joint function during three sets of knee extension exercise. METHODS: Sixty-five healthy males (23.3 years, 175.8 cm, 75.3 kg) underwent testing using the administration of verbal encouragement (n= 32) or not (n= 33) during assessment of quadriceps and knee joint function. Assessments were performed at baseline and times 1, 2, and 3. The knee concentric isokinetic extension at 60∘/s, was performed between the time points. For quadriceps function, maximal isometric strength and activation (central activation ratio) were recorded. Absolute error values on knee flexion replications at 15∘ or 45∘ were recorded for knee joint function. RESULTS: There was no verbal encouragement effect over three sets of exercise in quadriceps strength (condition × time: F3,189= 1.71, p= 0.17) and knee flexion replication (condition × time for 15∘: F3,189= 0.11, p= 0.96; 45∘: F3,189= 0.63, p= 0.6). However, subjects who had received verbal encouragement maintained quadriceps activation (condition × time: F3,189= 5.49, p= 0.001). Specifically, quadriceps activation in the verbal condition was 3.0% higher at time 2 (p= 0.01) and 4.7% higher at time 3 (p= 0.0003) versus in the non-verbal condition. CONCLUSIONS: Verbal encouragement appears to be effective in maintaining central activation, but is insufficient for promoting strength. This supports the idea that peripheral contributing factors play a larger role in force production when performing multiple sets of exercises.

scholarly journals Closing the Wearable Gap—Part VIII: A Validation Study for a Smart Knee Brace to Capture Knee Joint Kinematics

Biomechanics ◽  
2021 ◽  
Vol 1 (1) ◽  
pp. 152-162
Author(s):  
Alana J. Turner ◽  
Will Carroll ◽  
Sachini N. K. Kodithuwakku Arachchige ◽  
David Saucier ◽  
Reuben F. Burch V ◽  
...  
Keyword(s):  
Knee Joint ◽  
Motion Capture ◽  
Knee Flexion ◽  
Goodness Of Fit ◽  
Weight Bearing ◽  
Critical Role ◽  
Joint Kinematics ◽  
Knee Brace ◽  
Flexion Extension ◽  
Knee Joint Kinematics

Background: Wearable technology is used by clinicians and researchers and play a critical role in biomechanical assessments and rehabilitation. Objective: The purpose of this research is to validate a soft robotic stretch (SRS) sensor embedded in a compression knee brace (smart knee brace) against a motion capture system focusing on knee joint kinematics. Methods: Sixteen participants donned the smart knee brace and completed three separate tasks: non-weight bearing knee flexion/extension, bodyweight air squats, and gait trials. Adjusted R2 for goodness of fit (R2), root mean square error (RMSE), and mean absolute error (MAE) between the SRS sensor and motion capture kinematic data for all three tasks were assessed. Results: For knee flexion/extension: R2 = 0.799, RMSE = 5.470, MAE = 4.560; for bodyweight air squats: R2 = 0.957, RMSE = 8.127, MAE = 6.870; and for gait trials: R2 = 0.565, RMSE = 9.190, MAE = 7.530 were observed. Conclusions: The smart knee brace demonstrated a higher goodness of fit and accuracy during weight-bearing air squats followed by non-weight bearing knee flexion/extension and a lower goodness of fit and accuracy during gait, which can be attributed to the SRS sensor position and orientation, rather than range of motion achieved in each task.

Functional Knee Brace Alters Predicted Knee Muscle and Joint Forces in People with ACL Reconstruction during Walking

2001 ◽  
Vol 17 (4) ◽  
pp. 297-311 ◽  
Author(s):  
Paul DeVita ◽  
Tibor Hortobagyi
Keyword(s):  
Knee Joint ◽  
Lower Extremity ◽  
Acl Reconstruction ◽  
Shear Force ◽  
Stance Phase ◽  
Sagittal Plane ◽  
Healthy People ◽  
Healthy Individuals ◽  
Knee Brace ◽  
Knee Braces

Functional knee braces used during rehabilitation from injury and surgery to the anterior cruciate ligament (ACL) have been reported to provide a strain-shielding effect on the ACL in healthy people while standing, reduce quadriceps electromyoraphy in ACL-deficient individuals, and alter joint torque patterns in people with ACL reconstruction during walking. These results led to the hypothesis that functional knee braces protect a reconstructed ACL during dynamic activity by reducing the anterior shear load applied to the knee. This hypothesis was tested by investigating the effects of a functional knee brace on lower extremity muscle forces and the anteroposterior shear force at the knee joint during the stance phase of walking in people with ACL reconstruction. Ground reactions and sagittal plane video were recorded from 9 ACL-reconstructed individuals as they walked with and without a functional knee brace, and from 10 healthy people without the functional knee brace. Inverse dynamics were used to calculate the net joint torques in the lower extremity during the stance phase. Hamstrings, quadriceps, and gastrocnemius muscle and knee anteroposterior shear force were then predicted with a sagittal-plane mathematical model. Compared to healthy individuals, those with ACL reconstruction walked with 78% more hamstrings impulse and 19% less quadriceps impulse (bothp< .05). The functional knee brace produced an additional 43% increase in hamstrings impulse and an additional 13% decrease in quadriceps impulse in the ACL group. Peak anterior knee shear force and anterior impulse were 41% lower and 16% lower in ACL vs. healthy individuals, respectively. The functional knee brace further reduced the peak knee shear force and impulse 28% and 19%, respectively, in the ACL group. It was concluded that a functional knee brace protects a reconstructed ACL during walking by altering muscle forces and reducing the anterior shear force applied to the knee joint.

scholarly journals Proprioception of Knee Joint in Athletes and Non-Athletes Obese

2016 ◽  
Vol 9 (2) ◽  
pp. 286 ◽  
Author(s):  
Hajar Moravveji ◽  
Ali Ghanbari ◽  
Fahimeh Kamali
Keyword(s):  
Knee Joint ◽  
Weight Bearing ◽  
Knee Extension ◽  
Normal Weight ◽  
Obese Group ◽  
Significant Difference ◽  
Angle Reproduction Test ◽  
Reproduction Test ◽  
Proprioceptive Function ◽  
Weight Groups

<p><strong>BACKGROUND</strong><strong>: </strong>Proprioception plays an integral role in the neuromotor control of the knee joint. The objective of this study was to evaluate the relationship of knee joint proprioception deficit and regular exercise activities with obesity.</p><p><strong>MATERIAL/METHOD</strong><strong>: </strong>In this case control study, we had 60 participants, aged 18 to 35 in four groups (15 athletes obese; 15 athletes with normal weight; 15 non-athletes obese; 15 non-athletes with normal weight). The average Body Mass Index for the obese groups was 33.50±(3.10) kg/m<sup>2</sup> and for the normal weight groups was 23.77±(2.94) kg/m<sup>2</sup>. We used a Biodex Multi-Joint System 4 Isokinetic Dynamometer to examine proprioception acuity as the amount of a subject's error when trying to reproduce a test knee extension angle (a measure of the joint position sense). We tested proprioception actively (active reproduction test; AAR) and passively (passive reproduction test; PAR) in the right leg.</p><p><strong>RESULTS: </strong>The non-athlete obese group had significantly poorer proprioception acuity in the knee extension movement compared to the normal weight groups and also compared to the athlete obese group. For knee active angle reproduction test AAR, a significant difference was found (p=0.011). The results for passive angle reproduction test PAR, revealed no significant differences between the four groups (p=0.596).</p><p><strong>CONCLUSIONS:</strong> The obese groups showed a deficit in the proprioception function in knee extension movement. Furthermore, the findings suggest that doing regular weight bearing training is associated with better proprioceptive function, even in obese groups. It could manifest that the deleterious effect of obesity on the knee joint proprioception might be stronger than the beneficial influence of exercise training.</p>

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