scholarly journals Seated-popliteal weight bearing prosthesis for a bilateral amputee

1998 ◽  
Vol 22 (1) ◽  
pp. 68-70
Author(s):  
S. F. Wilson ◽  
W. E. Fisher
Keyword(s):  
Patellar Tendon ◽  
Lower Limb ◽  
Weight Bearing ◽  
Ground Reaction Forces ◽  
Reaction Forces ◽  
Bilateral Lower Limb ◽  
Lower Limb Amputees ◽  
Realistic Goal

Bilateral lower limb amputees suffer from a lack of stability when seated without prostheses due to lack of ground reaction forces through the stumps. In patients for whom ambulation is not a realistic goal, the seated-popliteal weight bearing prosthesis provides a solution for stability when seated in a wheelchair, without the problem of tibial pressure experienced with patellar-tendon-bearing prostheses.

scholarly journals Quantifying the Regional Load-Bearing Ability of Trans-Tibial Stumps

2006 ◽  
Vol 30 (1) ◽  
pp. 25-34 ◽  
Author(s):  
Ming Zhang ◽  
Winson C. C. Lee
Keyword(s):  
Patellar Tendon ◽  
Lower Limb ◽  
Regional Difference ◽  
Weight Bearing ◽  
Force Transducer ◽  
Pain Level ◽  
Load Bearing ◽  
Interface Materials ◽  
Lower Limb Amputees ◽  
Increasing Load

This paper reports findings of experiments aiming to (1) compare the load tolerant ability over different regions of stumps of lower limb amputees, (2) study the effect of walking on the load tolerant ability, and (3) examine the distal-end weight-bearing ability supported by different interface materials. The method was to apply increasing load to the stump up to the pain level through a force transducer or a digital scale, considering the effect of regional difference, walking, and interface materials. The results show that the patellar tendon and the distal end of the fibula were the best and worst load-tolerant region, respectively. Walking with prostheses tended to increase the load-tolerant ability, which is thought to be due to the massage-like effect of the socket. Different interface materials did not significantly alter the distal-end weight-bearing ability. However, there was a great difference in the distal-end weight-bearing ability among different subjects.

scholarly journals Running ground reaction forces across footwear conditions are predicted from the motion of two body mass components

2019 ◽  
Vol 126 (5) ◽  
pp. 1315-1325 ◽  
Author(s):  
Andrew B. Udofa ◽  
Kenneth P. Clark ◽  
Laurence J. Ryan ◽  
Peter G. Weyand
Keyword(s):  
Ground Reaction Force ◽  
Lower Limb ◽  
Reaction Force ◽  
Ground Reaction Forces ◽  
Vertical Ground Reaction Force ◽  
Time Patterns ◽  
Foot Strike ◽  
Reaction Forces ◽  
Vertical Ground ◽  
Force Time

Although running shoes alter foot-ground reaction forces, particularly during impact, how they do so is incompletely understood. Here, we hypothesized that footwear effects on running ground reaction force-time patterns can be accurately predicted from the motion of two components of the body’s mass (mb): the contacting lower-limb (m1 = 0.08mb) and the remainder (m2 = 0.92mb). Simultaneous motion and vertical ground reaction force-time data were acquired at 1,000 Hz from eight uninstructed subjects running on a force-instrumented treadmill at 4.0 and 7.0 m/s under four footwear conditions: barefoot, minimal sole, thin sole, and thick sole. Vertical ground reaction force-time patterns were generated from the two-mass model using body mass and footfall-specific measures of contact time, aerial time, and lower-limb impact deceleration. Model force-time patterns generated using the empirical inputs acquired for each footfall matched the measured patterns closely across the four footwear conditions at both protocol speeds ( r2 = 0.96 ± 0.004; root mean squared error  = 0.17 ± 0.01 body-weight units; n = 275 total footfalls). Foot landing angles (θF) were inversely related to footwear thickness; more positive or plantar-flexed landing angles coincided with longer-impact durations and force-time patterns lacking distinct rising-edge force peaks. Our results support three conclusions: 1) running ground reaction force-time patterns across footwear conditions can be accurately predicted using our two-mass, two-impulse model, 2) impact forces, regardless of foot strike mechanics, can be accurately quantified from lower-limb motion and a fixed anatomical mass (0.08mb), and 3) runners maintain similar loading rates (ΔFvertical/Δtime) across footwear conditions by altering foot strike angle to regulate the duration of impact. NEW & NOTEWORTHY Here, we validate a two-mass, two-impulse model of running vertical ground reaction forces across four footwear thickness conditions (barefoot, minimal, thin, thick). Our model allows the impact portion of the impulse to be extracted from measured total ground reaction force-time patterns using motion data from the ankle. The gait adjustments observed across footwear conditions revealed that runners maintained similar loading rates across footwear conditions by altering foot strike angles to regulate the duration of impact.

scholarly journals Simulation of Stand-to-Sit Biomechanics for Design of Lower-Limb Exoskeletons and Prostheses with Energy Regeneration

2019 ◽  
Author(s):  
Brock Laschowski ◽  
Reza Sharif Razavian ◽  
John McPhee
Keyword(s):  
Lower Limb ◽  
Electrical Energy ◽  
Mechanical Power ◽  
Future Research ◽  
Ground Reaction Forces ◽  
Dynamic Simulations ◽  
Inverse Dynamic ◽  
Joint Torques ◽  
Reaction Forces ◽  
Body Segment Parameters

AbstractAlthough regenerative actuators can extend the operating durations of robotic lower-limb exoskeletons and prostheses, these energy-efficient powertrains have been exclusively designed and evaluated for continuous level-ground walking.ObjectiveHere we analyzed the lower-limb joint mechanical power during stand-to-sit movements using inverse dynamic simulations to estimate the biomechanical energy available for electrical regeneration.MethodsNine subjects performed 20 sitting and standing movements while lower-limb kinematics and ground reaction forces were measured. Subject-specific body segment parameters were estimated using parameter identification, whereby differences in ground reaction forces and moments between the experimental measurements and inverse dynamic simulations were minimized. Joint mechanical power was calculated from net joint torques and rotational velocities and numerically integrated over time to determine joint biomechanical energy.ResultsThe hip produced the largest peak negative mechanical power (1.8 ± 0.5 W/kg), followed by the knee (0.8 ± 0.3 W/kg) and ankle (0.2 ± 0.1 W/kg). Negative mechanical work from the hip, knee, and ankle joints per stand-to-sit movement were 0.35 ± 0.06 J/kg, 0.15 ± 0.08 J/kg, and 0.02 ± 0.01 J/kg, respectively.Conclusion and SignificanceAssuming an 80-kg person and previously published regenerative actuator efficiencies (i.e., maximum 63%), robotic lower-limb exoskeletons and prostheses could theoretically regenerate ~26 Joules of total electrical energy while sitting down, compared to ~19 Joules per walking stride. Given that these regeneration performance calculations are based on healthy young adults, future research should include seniors and/or rehabilitation patients to better estimate the biomechanical energy available for electrical regeneration among individuals with mobility impairments.

Clinical Features and Outcomes Following Bilateral Lower Limb Amputation in Korea

2006 ◽  
Vol 30 (2) ◽  
pp. 155-164 ◽  
Author(s):  
Ji Cheol Shin ◽  
Eun Joo Kim ◽  
Chang Il Park ◽  
Eun Sook Park ◽  
Kyoo-Ho Shin
Keyword(s):  
Clinical Features ◽  
Lower Limb ◽  
Daily Living ◽  
Lower Limb Amputation ◽  
Limb Amputation ◽  
Medical Problems ◽  
Amputation Level ◽  
Significant Difference ◽  
Bilateral Lower Limb ◽  
Lower Limb Amputees

The objectives of this study were to evaluate the clinical features and outcomes of 43 bilateral lower limb amputees. The clinical features obtained included the causes of amputation, level of amputation, concurrent medical problems, and stump condition. Outcome measures were obtained using the activities of daily living (ADL) index, the Frenchay Activities Index (FAI), and mobility grading with prostheses or wheelchair. Of 33 amputees who were prosthetic ambulators, 22 (67%), mainly bilateral trans-tibial (TT) amputees, were community ambulators, and participated in activities which included stair-walking, and six of 11 household ambulators were combination trans-femoral (TF) and TT amputees. Of 10 amputees who were wheelchair ambulators, only one was able to perform wheelchair transfers independently and five were independent wheelchair ambulators. Using the ADL index and FAI, there was no significant difference in scores according to the level of amputation ( p > 0.05), but the scores of community prosthetic ambulators were significantly higher than those of wheelchair ambulators ( p < 0.05). Age was found to be negatively correlated with ADL index and FAI scores ( r = −0.518 vs. r = −0.550) ( p < 0.01). This study concludes that overall independence in ADL after bilateral lower limb amputation improved with young age and prosthetic mobility.

Reduced prosthetic stiffness lowers the metabolic cost of running for athletes with bilateral transtibial amputations

2017 ◽  
Vol 122 (4) ◽  
pp. 976-984 ◽  
Author(s):  
Owen N. Beck ◽  
Paolo Taboga ◽  
Alena M. Grabowski
Keyword(s):  
Lower Limb ◽  
Metabolic Cost ◽  
Ground Reaction Forces ◽  
Metabolic Rates ◽  
Distance Running ◽  
Cost Of Transport ◽  
Leg Stiffness ◽  
Metabolic Costs ◽  
In Series ◽  
Reaction Forces

Inspired by the springlike action of biological legs, running-specific prostheses are designed to enable athletes with lower-limb amputations to run. However, manufacturer’s recommendations for prosthetic stiffness and height may not optimize running performance. Therefore, we investigated the effects of using different prosthetic configurations on the metabolic cost and biomechanics of running. Five athletes with bilateral transtibial amputations each performed 15 trials on a force-measuring treadmill at 2.5 or 3.0 m/s. Athletes ran using each of 3 different prosthetic models (Freedom Innovations Catapult FX6, Össur Flex-Run, and Ottobock 1E90 Sprinter) with 5 combinations of stiffness categories (manufacturer’s recommended and ± 1) and heights (International Paralympic Committee’s maximum competition height and ± 2 cm) while we measured metabolic rates and ground reaction forces. Overall, prosthetic stiffness [fixed effect (β) = 0.036; P = 0.008] but not height ( P ≥ 0.089) affected the net metabolic cost of transport; less stiff prostheses reduced metabolic cost. While controlling for prosthetic stiffness (in kilonewtons per meter), using the Flex-Run (β = −0.139; P = 0.044) and 1E90 Sprinter prostheses (β = −0.176; P = 0.009) reduced net metabolic costs by 4.3–4.9% compared with using the Catapult prostheses. The metabolic cost of running improved when athletes used prosthetic configurations that decreased peak horizontal braking ground reaction forces (β = 2.786; P = 0.001), stride frequencies (β = 0.911; P < 0.001), and leg stiffness values (β = 0.053; P = 0.009). Remarkably, athletes did not maintain overall leg stiffness across prosthetic stiffness conditions. Rather, the in-series prosthetic stiffness governed overall leg stiffness. The metabolic cost of running in athletes with bilateral transtibial amputations is influenced by prosthetic model and stiffness but not height. NEW & NOTEWORTHY We measured the metabolic rates and biomechanics of five athletes with bilateral transtibial amputations while running with different prosthetic configurations. The metabolic cost of running for these athletes is minimized by using an optimal prosthetic model and reducing prosthetic stiffness. The metabolic cost of running was independent of prosthetic height, suggesting that longer legs are not advantageous for distance running. Moreover, the in-series prosthetic stiffness governs the leg stiffness of athletes with bilateral leg amputations.

Mobility, prosthesis use and health-related quality of life of bilateral lower limb amputees from the 2008 Sichuan earthquake

2018 ◽  
Vol 43 (1) ◽  
pp. 104-111 ◽  
Author(s):  
Wing Sum Li ◽  
Sze Ying Chan ◽  
Wai Wang Chau ◽  
Sheung-wai Law ◽  
Kai Ming Chan
Keyword(s):  
Quality Of Life ◽  
Lower Limb ◽  
Sichuan Earthquake ◽  
Factors Associated ◽  
Rehabilitation Outcomes ◽  
Related Quality ◽  
Health Related ◽  
Bilateral Lower Limb ◽  
Lower Limb Amputees

Background: The 2008 Sichuan Earthquake resulted in many amputees, yet due to the rare incidence, few studies have explored the rehabilitation outcomes and quality of life of bilateral lower limb amputees after major natural disasters. Objectives: To evaluate rehabilitation outcomes of 17 young and adult bilateral lower limb amputees under the StandTall rehabilitation programme and to identify factors associated with successful functional recovery of bilateral amputees after large-scale disasters. Study Design: Cross-sectional study. Methods: Mobility (amputee mobility predictor), prosthesis use (Houghton Scale) and health-related quality of life (Trinity Amputation and Prosthesis Experience Scale, Short Form 12) were evaluated through questionnaires and performance-based assessments. Means of scores were compared using T-tests. Results: Subjects with bilateral through-knee or transtibial amputations had less activity restriction ( p < 0.01) and higher mobility ( p = 0.03). Subjects using prostheses more than 50% waking time had better general adjustment ( p = 0.02) and less functional restriction ( p = 0.01). Exercise and education were associated with higher mobility ( p = 0.06) and mental quality of life, respectively ( p = 0.09). Conclusions: Amputation level and knee joint salvage, prosthesis use, exercise and education were associated with better rehabilitation outcomes including ambulation, adjustment and quality of life in bilateral lower limb amputees from the 2008 Sichuan Earthquake. Clinical relevance The study examined a unique group of traumatic bilateral lower limb amputees who were young and healthy before having traumatic amputations from a single episode of natural disaster. The factors associated with better functional recovery after the earthquake were investigated and may support future development of post-disaster rehabilitation strategies for bilateral lower limb amputees.

scholarly journals The effect of walking speed on the foot inter-segment kinematics, ground reaction forces and lower limb joint moments

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5517 ◽  
Author(s):  
Dong Sun ◽  
Gusztáv Fekete ◽  
Qichang Mei ◽  
Yaodong Gu
Keyword(s):  
Lower Limb ◽  
Walking Speed ◽  
Sagittal Plane ◽  
External Rotation ◽  
Center Of Mass ◽  
Ground Reaction Forces ◽  
Joint Moments ◽  
Angle Variation ◽  
Foot Kinematics ◽  
Reaction Forces

Background Normative foot kinematic and kinetic data with different walking speeds will benefit rehabilitation programs and improving gait performance. The purpose of this study was to analyze foot kinematics and kinetics differences between slow walking (SW), normal walking (NW) and fast walking (FW) of healthy subjects. Methods A total of 10 healthy male subjects participated in this study; they were asked to carry out walks at a self-selected speed. After measuring and averaging the results of NW, the subjects were asked to perform a 25% slower and 25% faster walk, respectively. Temporal-spatial parameters, kinematics of the tibia (TB), hindfoot (HF), forefoot (FF) and hallux (HX), and ground reaction forces (GRFs) were recorded while the subjects walked at averaged speeds of 1.01 m/s (SW), 1.34 m/s (NW), and 1.68 m/s (FW). Results Hindfoot relative to tibia (HF/TB) and forefoot relative to hindfoot (FF/HF) dorsiflexion (DF) increased in FW, while hallux relative to forefoot (HX/FF) DF decreased. Increased peak eversion (EV) and peak external rotation (ER) in HF/TB were observed in FW with decreased peak supination (SP) in FF/HF. GRFs were increased significantly with walking speed. The peak values of the knee and ankle moments in the sagittal and frontal planes significantly increased during FW compared with SW and NW. Discussion Limited HF/TB and FF/HF motion of SW was likely compensated for increased HX/FF DF. Although small angle variation in HF/TB EV and FF/HF SP during FW may have profound effects for foot kinetics. Higher HF/TB ER contributed to the FF push-off the ground while the center of mass (COM) progresses forward in FW, therefore accompanied by higher FF/HF abduction in FW. Increased peak vertical GRF in FW may affected by decreased stance duration time, the biomechanical mechanism maybe the change in vertical COM height and increase leg stiffness. Walking speed changes accompanied with modulated sagittal plane ankle moments to alter the braking GRF during loading response. The findings of foot kinematics, GRFs, and lower limb joint moments among healthy males may set a reference to distinguish abnormal and pathological gait patterns.

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