Reduced cortical brain activity with the use of microprocessor-controlled prosthetic knees during walking

Background: Individuals using a lower-limb prosthesis indicate that they need to concentrate on every step they take. Despite self-reports of increased cognitive demand, there is limited understanding of the link between cognitive processes and walking when using a lower-limb prosthesis. Objective: The objective was to assess cortical brain activity during level walking in individuals using different prosthetic knee components and compare them to healthy controls. It was hypothesized that the least activity would be observed in the healthy control group, followed by individuals using a microprocessor-controlled prosthetic knee and finally individuals using a non-microprocessor-controlled prosthetic knee. Study design: Cross-sectional study. Methods: An optical brain imaging system was used to measure relative changes in concentration of oxygenated and de-oxygenated haemoglobin in the frontal and motor cortices during level walking. The number of steps and time to walk 10 m was also recorded. The 6-min walk test was assessed as a measure of functional capacity. Results: Individuals with a transfemoral or knee-disarticulation amputation, using non-microprocessor-controlled prosthetic knee ( n = 14) or microprocessor-controlled prosthetic knee ( n = 15) joints and healthy controls ( n = 16) participated in the study. A significant increase was observed in cortical brain activity of individuals walking with a non-microprocessor-controlled prosthetic knee when compared to healthy controls ( p < 0.05) and individuals walking with an microprocessor-controlled prosthetic knee joint ( p < 0.05). Conclusion: Individuals walking with a non-microprocessor-controlled prosthetic knee demonstrated an increase in cortical brain activity compared to healthy individuals. Use of a microprocessor-controlled prosthetic knee was associated with less cortical brain activity than use of a non-microprocessor-controlled prosthetic knee. Clinical relevance Increased understanding of cognitive processes underlying walking when using different types of prosthetic knees can help to optimize selection of prosthetic components and provide an opportunity to enhance functioning with a prosthesis.

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A magnetorheological damper-based prosthetic knee (MRPK) and sliding mode tracking control method for an MRPK-based lower limb prosthesis

Smart Materials and Structures ◽

10.1088/1361-665x/aa61f1 ◽

2017 ◽

Vol 26 (4) ◽

pp. 045030 ◽

Cited By ~ 16

Author(s):

Qiang Fu ◽

Dai-Hua Wang ◽

Lei Xu ◽

Gang Yuan

Keyword(s):

Lower Limb ◽

Tracking Control ◽

Control Method ◽

Sliding Mode ◽

Magnetorheological Damper ◽

Prosthetic Knee ◽

Lower Limb Prosthesis ◽

Mode Tracking ◽

Limb Prosthesis

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USING PERFORATED LINERS TO COMBAT THE DETRIMENTAL EFFECTS OF EXCESSIVE SWEATING IN LOWER LIMB PROSTHESIS USERS

Canadian Prosthetics & Orthotics Journal ◽

10.33137/cpoj.v3i2.34610 ◽

2020 ◽

Vol 3 (2) ◽

Author(s):

Katherine C. Davies ◽

Mike McGrath ◽

Alison Stenson ◽

Zoe Savage ◽

David Moser ◽

...

Keyword(s):

Lower Limb ◽

The Body ◽

Limb Amputation ◽

Control Group ◽

Residual Limb ◽

Excessive Sweating ◽

Lower Limb Prosthesis ◽

Skin Conditions ◽

The Impact ◽

Limb Prosthesis

BACKGROUND: Excessive sweating of the residual limb has a substantial effect on the daily activities of people with lower limb amputation. Prosthetic liners offer protection and comfort to sensitive areas but often exacerbate perspiration. They act as insulators, trapping sweat on the skin’s surface to the detriment of skin health. Recently, liners with perforations have been developed, allowing the moisture to escape. The goal of this study was to assess the impact of such liners. METHODS: A sample group of 13 patients with unilateral transtibial amputation, who wore a perforated liner (PL) as part of their current prescription, was compared to 20 control patients who wore non-perforated liners (NPL). During their routine appointments, they completed a survey of scientifically validated outcome measures relating to their limb health, pain and the impact on daily life over a 12-month period. RESULTS: Patients using the PL had healthier residual limbs, reporting higher scores on questions relating to limb health, experiencing fewer skin issues (p<0.001) and estimating a 61.8% lower rating in perceived sweat (p=0.004). Perhaps consequentially, there was a lower incidence of residual (p=0.012) and phantom (p=0.001) limb pain when compared to the control group. The prevalence of individual issues affecting the residual limbs of PL users was also lower. Of the issues that remained, only 23% were attributed to sweating in PL users, compared to 49% for the NPL group (p=0.066). PL users missed fewer days of work in the year (2.4 vs 11.6, p=0.267) and were also limited on fewer days (1.4 vs 75.4, p=0.009). CONCLUSION: The use of perforated liners shows much promise within prosthetic care, significantly improving the health of the residual limb. The observed effects on perceived sweat reduction, residual skin health, pain levels and patient limitation suggest that perforated liners are highly beneficial to patients. Layman's Abstract Individuals with amputation often find that they sweat more as they exert more energy when walking and because the total surface area of their body is reduced. Silicone liners are used to cushion the residual limb and as a way of attaching a prosthetic leg, but they act as insulators causing the residual limb to get hot and sweaty. The material isn’t breathable, so the sweat is not able to escape, instead staying on the skin’s surface and causing discomfort or leading to the development of skin conditions. Liners that have small holes in them allow sweat to travel away from the body and preserve skin health. Patients who wore a perforated liner, as well as patients who wore a liner without holes, filled in questionnaires about their experience, the results of which were compared. Generally, patients who wore the perforated liner had healthier skin on their residual limbs and experienced fewer skin conditions than the other patient group. Out of the issues they did experience, fewer were attributed to sweating. The study group experienced less frequent pain both in their physical and phantom limbs. They also considered themselves less limited by their prosthetic device and missed fewer days of work. These observations suggest that perforated liners are highly beneficial to patients within the prosthetic field. Article PDF Link: https://jps.library.utoronto.ca/index.php/cpoj/article/view/34610/26579 How To Cite: Davies K.C, McGrath M, Savage Z, Stenson A, Moser D, Zahedi S. Using perforated liners to combat the detrimental effects of excessive sweating in lower limb prosthesis users. Canadian Prosthetics & Orthotics Journal. 2020;Volume 3, Issue 2, No.1. https://doi.org/10.33137/cpoj.v3i2.34610 Corresponding Author: K.C Davies, Blatchford Group, Unit D Antura, Bond Close, Basingstoke, RG24 8PZ, UK.E-mail: [email protected]: https://orcid.org/0000-0003-2933-4365

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A low-cost easily implementable physiotherapy intervention clinically improves gait implying better adaptation to lower limb prosthesis: a randomized clinical trial

Scientific Reports ◽

10.1038/s41598-021-00686-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Leticia Vargas Almeida ◽

Claudiane Arakaki Fukuchi ◽

Tania Emi Sakanaka ◽

Alberto Cliquet

Keyword(s):

Lower Limb ◽

Low Cost ◽

Intervention Group ◽

Lower Limb Amputation ◽

Limb Amputation ◽

Control Group ◽

Post Intervention ◽

Physiotherapy Intervention ◽

Lower Limb Prosthesis ◽

Limb Prosthesis

AbstractLower limb amputation highly impacts the lives of individuals. The inability to walk due to difficulties in adapting to wearing prosthesis can potentially result in physical degeneration and comorbidity in this population. In this randomized clinical trial study, we investigated if a low-cost and easily implementable physiotherapy intervention was effective in improving gait performance and adaptation to lower limb prosthesis in individuals with an amputation. A total of 26 individuals participated in the study, 16 with lower limb amputation and 10 without amputation. Participants with amputation were further divided in intervention and control groups. The intervention group underwent a rehabilitation protocol aimed at strengthening muscles and improving prosthesis adaptation. Muscle strengthening targeted the hip segment, prioritizing the abdominal muscles, hip flexors, extensors, adductors and abductors, followed by cicatricial mobilization and weight-bearing on the stump for desensitization. Assessment and measures were performed across the kinetic and kinematic parameters of gait. In the comparison between pre-and post-intervention, a significant increase in gait speed (0.68—2.98, 95% CI, 1.83, effect size ES) and cadence (0.56—2.69, 95% CI, 1.63, ES) was found between groups and time points. Step (0.73—3.11, 95% CI, 1.92, ES) and stride length (0.62—2.84, 95% CI, 1.73) increased between pre- and post-intervention, while in the control group both variables remained smaller. The intervention group decreased stance phase as a percentage of gait cycle between pre- and post-intervention (− 1.33—0.62, 95% CI, − 36, ES), while it increased in the control group. Improvement in a combination of important gait parameters indicates that the intervention protocol promoted the adaptation to prosthesis and the functional independence of individuals with lower limb amputation. It is recommended that the participants continue receiving follow-up assessments and rehabilitation interventions.

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Intent Recognition in a Powered Lower Limb Prosthesis Using Time History Information

Annals of Biomedical Engineering ◽

10.1007/s10439-013-0909-0 ◽

2013 ◽

Vol 42 (3) ◽

pp. 631-641 ◽

Cited By ~ 64

Author(s):

Aaron J. Young ◽

Ann M. Simon ◽

Nicholas P. Fey ◽

Levi J. Hargrove

Keyword(s):

Lower Limb ◽

Time History ◽

Intent Recognition ◽

History Information ◽

Lower Limb Prosthesis ◽

Limb Prosthesis ◽

Powered Lower Limb Prosthesis

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Nonlinear Passive Cam-Based Springs for Powered Ankle Prostheses

Journal of Medical Devices ◽

10.1115/1.4028653 ◽

2015 ◽

Vol 9 (1) ◽

Cited By ~ 23

Author(s):

Jonathan Realmuto ◽

Glenn Klute ◽

Santosh Devasia

Keyword(s):

Lower Limb ◽

Nonlinear Response ◽

Experimental Results ◽

Passive Element ◽

Ankle Torque ◽

Lower Limb Prosthesis ◽

Limb Prosthesis ◽

Elastic Elements

This article studies the design of passive elastic elements to reduce the actuator requirements for powered ankle prostheses. The challenge is to achieve most of the typically nonlinear ankle response with the passive element so that the active ankle-torque from the actuator can be small. The main contribution of this article is the design of a cam-based lower-limb prosthesis to achieve such a nonlinear ankle response. Results are presented to show that the addition of the cam-based passive element can reduce the peak actuator torque requirement substantially, by ∼74%. Moreover, experimental results are presented to demonstrate that the cam-based design can achieve a desired nonlinear response to within 10%.

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