Single-leg forward hopping exposures adversely affect knee joint health among persons with unilateral lower limb loss: A predictive model

BACKGROUND: Joint loads in different walking strategies during stair descent have been investigated in terms of the joint moment in association with the risk of osteoarthritis. However, the absorption mechanisms of the potential energy loss are not known. OBJECTIVE: This study aims to compare the mechanical energy absorptions in lower limb joints in different initial foot contact strategies. METHODS: Nineteen young subjects walked down on instrumented stairs with two different strategies, i.e., forefoot and rearfoot strike. Power and energy at lower limb joints during stance phase were compared between strategies. RESULTS: Lower limb joints absorbed 73 ± 11% of the potential energy released by descending stairs and there was no difference between strategies. Rearfoot strategy absorbed less energy than forefoot strategy at the ankle joint in the 1st phase, which was compensated mainly by more energy absorption at the knee in the 2nd phase and less energy generation at the hip joints in the 3rd phase. CONCLUSION: The results suggest that a leg absorbs most of the potential energy while descending stairs irrespective of the walking strategies and that any reduction of energy absorption at one joint is compensated by other joints. Greater energy absorption at the knee joint compared to the other joints suggests high burden of knee joint muscles and connective tissues during stair-descent, which is even more significant for the rearfoot strike strategy.

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Estimation of Ground Reaction Forces Based on Knee Joint Acceleration of Lower-Limb Exoskeletons

2020 International Automatic Control Conference (CACS) ◽

10.1109/cacs50047.2020.9289732 ◽

2020 ◽

Author(s):

Tesheng Hsiao ◽

Kinglam Yip ◽

Yun-Jen Chiu

Keyword(s):

Knee Joint ◽

Lower Limb ◽

Ground Reaction Forces ◽

Reaction Forces ◽

Joint Acceleration

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Evaluation and Validation of a Joint Stress Test to Induce Activity-Related Knee Joint Discomfort — a Prospective Case-Control Study

Sports Medicine - Open ◽

10.1186/s40798-021-00317-7 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Christiane Schön ◽

Claudia Reule ◽

Katharina Knaub ◽

Antje Micka ◽

Manfred Wilhelm ◽

...

Keyword(s):

Knee Joint ◽

Healthy Subjects ◽

Stress Test ◽

Osteoarthritis Of The Knee ◽

Time Interval ◽

Short Time Interval ◽

Joint Stress ◽

Joint Health ◽

The Impact ◽

Health Function

Abstract Background The assessment of improvement or maintenance of joint health in healthy subjects is a great challenge. The aim of the study was the evaluation of a joint stress test to assess joint discomfort in subjects with activity-related knee joint discomfort (ArJD). Results Forty-five subjects were recruited to perform the single-leg-step-down (SLSD) test (15 subjects per group). Subjects with ArJD of the knee (age 22–62 years) were compared to healthy subjects (age 24–59 years) with no knee joint discomfort during daily life sporting activity and to subjects with mild-to-moderate osteoarthritis of the knee joint (OA, Kellgren score 2–3, age 42–64 years). The subjects performed the SLSD test with two different protocols: (I) standardization for knee joint discomfort; (II) standardization for load on the knee joint. In addition, range of motion (ROM), reach test, acute pain at rest and after a single-leg squat and knee injury, and osteoarthritis outcome score (KOOS) were assessed. In OA and ArJD subjects, knee joint discomfort could be reproducibly induced in a short time interval of less than 10 min (200 steps). In healthy subjects, no pain was recorded. A clear differentiation between study groups was observed with the SLSD test (maximal step number) as well as KOOS questionnaire, ROM, and reach test. In addition, a moderate to good intra-class correlation was shown for the investigated outcomes. Conclusions These results suggest the SLSD test is a reliable tool for the assessment of knee joint health function in ArJD and OA subjects to study the improvements in their activities. Further, this model can be used as a stress model in intervention studies to study the impact of stress on knee joint health function.

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Medial knee joint contact force in the intact limb during walking in recently ambulatory service members with unilateral limb loss: a cross-sectional study

PeerJ ◽

10.7717/peerj.2960 ◽

2017 ◽

Vol 5 ◽

pp. e2960 ◽

Cited By ~ 4

Author(s):

Ross H. Miller ◽

Rebecca L. Krupenevich ◽

Alison L. Pruziner ◽

Erik J. Wolf ◽

Barri L. Schnall

Keyword(s):

Knee Joint ◽

Limb Loss ◽

Service Members ◽

Model Parameters ◽

Joint Loading ◽

Cross Sectional ◽

Medial Knee ◽

Knee Oa ◽

Joint Contact ◽

Intact Limb

BackgroundIndividuals with unilateral lower limb amputation have a high risk of developing knee osteoarthritis (OA) in their intact limb as they age. This risk may be related to joint loading experienced earlier in life. We hypothesized that loading during walking would be greater in the intact limb of young US military service members with limb loss than in controls with no limb loss.MethodsCross-sectional instrumented gait analysis at self-selected walking speeds with a limb loss group (N = 10, age 27 ± 5 years, 170 ± 36 days since last surgery) including five service members with transtibial limb loss and five with transfemoral limb loss, all walking independently with their first prosthesis for approximately two months. Controls (N = 10, age 30 ± 4 years) were service members with no overt demographical risk factors for knee OA. 3D inverse dynamics modeling was performed to calculate joint moments and medial knee joint contact forces (JCF) were calculated using a reduction-based musculoskeletal modeling method and expressed relative to body weight (BW).ResultsPeak JCF and maximum JCF loading rate were significantly greater in limb loss (184% BW, 2,469% BW/s) vs. controls (157% BW, 1,985% BW/s), with large effect sizes. Results were robust to probabilistic perturbations to the knee model parameters.DiscussionAssuming these data are reflective of joint loading experienced in daily life, they support a “mechanical overloading” hypothesis for the risk of developing knee OA in the intact limb of limb loss subjects. Examination of the evolution of gait mechanics, joint loading, and joint health over time, as well as interventions to reduce load or strengthen the ability of the joint to withstand loads, is warranted.

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Limitations of body mass index for counseling individuals with unilateral lower extremity amputation

Prosthetics and Orthotics International ◽

10.1177/0309364616650079 ◽

2016 ◽

Vol 41 (2) ◽

pp. 186-193 ◽

Cited By ~ 3

Author(s):

Alexandra P Frost ◽

Tracy Norman Giest ◽

Allison A Ruta ◽

Teresa K Snow ◽

Mindy Millard-Stafford

Keyword(s):

Body Mass Index ◽

Lower Extremity ◽

Health Risk ◽

Body Mass ◽

Body Fat ◽

Lower Limb ◽

Dual Energy ◽

Limb Loss ◽

Percent Body Fat ◽

X Ray

Background: Body composition is important for health screening, but appropriate methods for unilateral lower extremity amputees have not been validated. Objectives: To compare body mass index adjusted using Amputee Coalition equations (body mass index–Amputee Coalition) to dual-energy X-ray absorptiometry in unilateral lower limb amputees. Study design: Cross-sectional, experimental. Methods: Thirty-eight men and women with lower limb amputations (transfemoral, transtibial, hip disarticulation, Symes) participated. Body mass index (mass/height2) was compared to body mass index corrected for limb loss (body mass index–Amputee Coalition). Accuracy of classification and extrapolation of percent body fat with body mass index was compared to dual-energy X-ray absorptiometry. Results: Body mass index–Amputee Coalition increased body mass index (by ~ 1.1 kg/m2) but underestimated and mis-classified 60% of obese and overestimated 100% of lean individuals according to dual-energy X-ray absorptiometry. Estimated mean percent body fat (95% confidence interval) from body mass index–Amputee Coalition (28.3% (24.9%, 31.7%)) was similar to dual-energy X-ray absorptiometry percent body fat (29.5% (25.2%, 33.7%)) but both were significantly higher ( p < 0.05) than percent body fat estimated from uncorrected body mass index (23.6% (20.4%, 26.8%)). However, total errors for body mass index and body mass index–Amputee Coalition converted to percent body fat were unacceptably large (standard error of the estimate = 6.8%, 6.2% body fat) and the discrepancy between both methods and dual-energy X-ray absorptiometry was inversely related ( r = −0.59 and r = −0.66, p < 0.05) to the individual’s level of body fatness. Conclusions: Body mass index (despite correction) underestimates health risk for obese patients and overestimates lean, muscular individuals with lower limb amputation. Clinical relevance Clinical recommendations for an ideal body mass based on body mass index–Amputee Coalition should not be relied upon in lower extremity amputees. This is of particular concern for obese lower extremity amputees whose health risk might be significantly underestimated based on body mass index despite a “correction” formula for limb loss.

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