Measurement and analysis of center of gravity and floor reaction force for human motion of standing up from a chair / toilet

Human-like motion prediction and simulation is an important task with many applications in fields such as occupational-biomechanics, ergonomics in industrial engineering, study of biomechanical systems, prevention of musculoskeletal disorders, computer-graphics animation of articulated figures, prosthesis and exoskeletons design as well as design and control of humanoid robots, among others. In an effort to get biomechanical insight in many human movements, extensive work has been conducted over the last decades on human-motion prediction of tasks as: walking, running, jumping, standing from a chair, reaching and lifting. This literature review is focused on the STS motion and the LLM. STS is defined as the process of rising from a chair to standing up position without losing stability balance, it is the most ubiquitous and torque-demanding daily labor and it is closely related to other capabilities of the human body. LLM is defined as the activity of raising a load, generally a box, from a low to a higher position while stability is maintained, this task produces a high number of incidences of low-back pain and injuries in many industrial and domestic activities. In order to predict STS and LLM, two methods have been identified: these are the OBMG method and the CBMG method.

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Jumping Mechanography is a Suitable Complementary Method to Assess Motor Function in Ambulatory Boys with Duchenne Muscular Dystrophy

Neuropediatrics ◽

10.1055/s-0041-1722880 ◽

2021 ◽

Author(s):

Astrid Blaschek ◽

Martin Rodrigues ◽

Rainer Rawer ◽

Christine Müller ◽

Lena Ille ◽

...

Keyword(s):

Clinical Trials ◽

Duchenne Muscular Dystrophy ◽

Muscular Dystrophy ◽

Reaction Force ◽

Drug Efficacy ◽

Measuring Method ◽

Physical Parameters ◽

First Choice ◽

Standing Up ◽

Jumping Mechanography

Abstract Objective The number of clinical trials for Duchenne muscular dystrophy (DMD) has increased substantially lately, therefore appropriate clinical instruments are needed to measure disease progression and drug efficacy. Jumping mechanography is a medical diagnostic method for motion analysis, which allows to quantify physical parameters. In this study, we compared mechanography with timed function tests (TFTs). Methods 41 ambulatory DMD patients performed a total of 95 chair rising tests (CRT) and a total of 76 single two-legged jumps (S2LJ) on a mechanography ground reaction force platform. The results were correlated with a 6-minute walk test (6MWT) and the time required to run 10 meters, stand up from a supine position, and climb four stairs, all performed in the same setting. Results Our measurements show a high correlation between mechanography and the TFTs: S2LJ/10-m run, r = 0.62; CRT/10-m run, r = 0.61; S2LJ/standing up from supine, r = 0.48; CRT/standing up from supine, r = 0.58; S2LJ/climb four stairs, r = 0.55; CRT/climb four stairs, r = 0.51. The correlation between mechanography and the 6MWT was only moderate with r = 0.38 for S2LJ/6MWT and r = 0.39 for CRT/6MWT. Interpretation Jumping mechanography is a reliable additional method, which can be used for physical endpoint measurements in clinical trials. We confirmed our assumption, that the method provides additional information concerning performance at movement with higher power output. We suggest using the S2LJ as a first-choice tandem tool combined with the 6MWT. In patients with higher disability, the CRT is an alternative measuring method, because with the progression of the disease this is longer feasible.

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