Radically different
Background: Stairclimbing wheelchairs offer enhanced mobility for users navigating multilevel environments, yet limited research addresses the ergonomics of lever propulsion-based stair climbing mechanisms. Comprehensive ergonomic assessment integrating both subjective user feedback and objective biomechanical analysis is essential for optimizing assistive device design for comfort and usability. Objective: This pilot study aims to assess the ergonomic design of a transformable stair-climbing wheelchair through a dual-methodology approach, evaluating plane surface movement accessibility and quantifying muscle activation patterns during lever-propelled stair-climbing operations using surface electromyography (sEMG). Methods: This 2-part study involved anthropometric measurements from 20 male participants to establish design parameters using 5th and 95th percentile values. Part A assessed plane surface movement with 9 participants (7 healthy, 2 with paraplegia) navigating a simulated urban course featuring a 5° ramp, a 90° turn, and narrow passages across 3 trials. Task completion times and subjective ride easiness ratings were recorded. Part B used a Taguchi-based fractional factorial design to evaluate 3 ergonomic factors, including torso angle (λ), lever distance (L), and lever orientation (ψ), across 7 healthy participants. Maximum voluntary contraction (MVC) was measured for 4 muscles, including biceps brachii long head (BBL), triceps brachii long head (TBL), brachioradialis, and posterior deltoid (PDT). Results: In Part A, the ramp and 90° turn proved most challenging due to the wheelchair’s 65 kg weight and large turning radius (~1450 mm). Driving control scored highest (6/10), while comfort scored lowest due to the tilted seat design. In Part B, a straight torso (λ=0°) consistently reduced muscle strain, particularly for brachioradialis. A lever distance of approximately 50 mm and a neutral to slightly supinated orientation (ψ=0°-30°) optimized muscle effort. Interaction effects revealed high strain configurations (λ=45°; L=100 mm; ψ=−30°) exceeding 75 MVC, while optimal settings reduced strain to approximately 50 MVC. Conclusions: Optimal ergonomic parameters of λ=0°, L=37.5 mm, and ψ=15° are recommended to minimize fatigue and enhance user comfort. Design improvements should prioritize weight reduction, compact form factor for maneuverability, and adjustable seat tilt. The modular wheelchair design permits customization for diverse user populations. Future research should include larger, gender-diverse participant groups and real-world validation studies.
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More than 150 companies and providers have been provisionally approved to participate in an experimental Medicare program meant to expand access to technology-supported chronic care. They include popular mental health apps, wearable device makers, a life sciences company tied to Google, and startups that help large health systems manage heart failure patients.
Announced late last year by the Center for Medicare and Medicaid Innovation, the ACCESS model will pay participants set rates to treat chronic conditions like diabetes, hypertension, high cholesterol, musculoskeletal pain, anxiety, and depression. The payments are tied to measurable health outcomes; the model is meant as an alternative to paying for individual technology services. The initial deadline to participate in the first ACCESS cohort was April 1, but CMMI Monday announced it will extend the deadline to allow more to join.
CMS officials say the large number of applications to participate in ACCESS exceeded their expectations and that the enthusiasm suggests modest payment rates and restrictions did not discourage digital health companies from applying. According to officials, most of the participants had not previously served Medicare patients.
This drug delivery wearable’s micropump needed an engineered solution for both adhesion and slip. By Philipp Begert, Trelleborg Medical Solutions I want to take you straight to the heart of a project that challenged not only my team’s technical skills, but the fundamentals of medical device engineering. It’s a classic example of requirements in conflict.…
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NEWS RELEASE: FUCHS Lubricants Co. spotlights NYEMED 7477 high-performance medical grease Engineered for extreme conditions and broad material compatibility FUCHS Lubricants Co., the world’s largest independent lubricant manufacturer, highlights NYEMED 7477, a high-performance, general-purpose grease engineered for medical device environments where durability and patient safety are critical. Designed for applications exposed to thermal stress, mechanical load,…
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