Measure It: Proper Wheelchair Fit Is Key to Ensuring Function while Protecting Skin Integrity.

General Purpose: To review the biomechanics of posture, appropriate means to configure a wheelchair to permit proper postural support, and common problems arising from improper wheelchair fit.

Target Audience: This continuing education activity is intended for physicians, physician assistants, nurse practitioners, and nurses with an interest in skin and wound care.

Learning Objectives/outcomes: After participating in this educational activity, the participant will:1.

The design of a family of parametric anatomically-based compliant buttock models to evaluate wheelchair cushion performance.

The evaluation of wheelchair cushion performance is of interest to a variety of stakeholders, including standards organizations, cushion manufacturers, clinicians, users and payers. The objective of this project was to develop a family of compliant buttock models that are based upon the anatomical parameters of persons with varying body sizes. The models are parametrically designed so can be scaled to evaluate different sized cushions.

Evaluating bottoming-out of bariatric sized wheelchair cushions.

In the United States, wheelchair cushions are classified using HCPCS codes. Cushions classified as Skin Protection cushions are provided for wheelchair users who are at risk of tissue damage. Cushions designed for bariatric users fall into a category of cushions with width of 22 inches or greater.

Effects of Incremental Changes to Frame Mass on Manual Wheelchair Propulsion Cost.

The objective of this study was to assess the effects of small, incremental additions to wheelchair frame mass (0 kg, +2 kg, and +4 kg) on the mechanical propulsion characteristics in both straight and curvilinear maneuvers. A robotic propulsion system was used to propel a manual wheelchair over a smooth tiled surface following rectilinear ("Straight") and curvilinear ("Slalom") trajectories. Three unique loading conditions were tested.

Does Sacrococcygeal Skeletal Morphology and Morphometry Influence Pressure Injury Formation in Adults?

General Purpose: To present a study that investigated sacrococcygeal skeletal structure as a possible nonmodifiable intrinsic risk factor for pressure injury and identify possible issues caused by its morphology.

Target Audience: This continuing education activity is intended for physicians, physician assistants, nurse practitioners, and nurses with an interest in skin and wound care.

Learning Objectives/outcomes: After participating in this educational activity, the participant will:1.

The relationship between in-seat movement and pressure ulcers in wheelchair users with SCI/D.

Objective: To identify parameters that are associated with time at pressure, are most related to pressure ulcer outcomes, and that may be used to influence pressure ulcer (PrU) outcomes in future intervention studies.

Design: Analysis used datasets from cross-sectional and longitudinal observational studies. Wheelchair-usage and in-seat metrics thresholds were optimized to differentiate individuals in PrU or No PrU groups.

Procedure to categorize wheelchair cushion performance using compliant buttock models.

Wheelchair cushion prescription often seeks to address tissue integrity in addition to other clinical indicators. Because hundreds of wheelchair cushion models are available, a benefit would result if cushions were classified in a more valid manner to help guide selection by clinicians and users. The objective of this research was to develop an approach to evaluate and classify wheelchair cushion performance with respect to pressure redistribution.

Effect of Wheels, Casters and Forks on Vibration Attenuation and Propulsion Cost of Manual Wheelchairs.

Manual wheelchair users are exposed to whole-body vibrations as a direct result of using their wheelchair. Wheels, tires, and caster forks have been developed to reduce or attenuate the vibration that transmits through the frame and reaches the user. Five of these components with energy-absorbing characteristics were compared to standard pneumatic drive wheels and casters.

Estimating whole-body vibration limits of manual wheelchair mobility over common surfaces.

Whole-body vibration (WBV) experienced during manual wheelchair use was quantified across several types of terrain (tile, sidewalk, decorative bricks, expanded metal grates). Over-ground travel was controlled using a robotic propulsion system. Vibrations along the vertical axis were measured with a triaxial accelerometer mounted to the seat of the wheelchair.

Propulsion Cost Changes of Ultra-Lightweight Manual Wheelchairs After One Year of Simulated Use.

Manual wheelchairs are available with folding or rigid frames to meet the preferences and needs of individual users. Folding styles are commonly regarded as more portable and storable, whereas rigid frames are commonly regarded as more efficient for frequently daily use. To date, there are no studies directly comparing the performances of the frame types.

Effects of wheels and tires on high-strength lightweight wheelchair propulsion cost using a robotic wheelchair tester.

Purpose: This study was designed to investigate the effect of wheel and tire selections on the propulsion characteristics of a high-strength lightweight manual wheelchair using robotic wheelchair propulsion.

Materials And Methods: Four configurations were compared with differing combinations of drive wheel tires and casters, with the baseline reflecting the manufacturer configuration of a solid mag drive wheel and 8"×1" caster. The robotic wheelchair tester propelled the chair using pre-generated straight and curvilinear manoeuvres using repeatable and reliable cyclic torque profiles.

An Exploratory Analysis of the Role of Adipose Characteristics in Fulltime Wheelchair Users' Pressure Injury History.

The goals of this study were 1) to identify the relationship between adipose (subcutaneous and intramuscular) characteristics and pressure injury (PrI) history in wheelchair users and 2) to identify subject characteristics, including biomechanical risk, that are related to adipose characteristics. The buttocks of 43 full-time wheelchair users with and without a history of pelvic PrIs were scanned in a seated posture in a FONAR UPRIGHT® MRI. Intramuscular adipose (the relative difference in intensity between adipose and gluteus maximus) and the subcutaneous adipose characteristics (the relative difference in intensity between subcutaneous adipose under and surrounding the ischium) were compared to PrI history and subject characteristics.

Validating a wheelchair in-seat activity tracker.

Wheelchair users often experience prolonged periods of stationary sitting. Such periods are accompanied with increased loading of the ischial tuberosities. This can lead to the development of pressure ulcers which can cause complications such as sepsis.

Friction characteristics of preventative wound dressings under clinically-relevant conditions.

Wound dressings can be used prophylactically or during actual treatment. Preventative dressings have become a standard of care to prevent pressure ulcers in patients while in bed. While the mechanism of the preventative benefit has not been completely explained, the friction between the dressing and linen is hypothesized as being a key performance factor.

Assessment of wheeled mobility devices provided to a commercially insured population in 2017.

In the United States, wheeled mobility devices (WMD) are classified as durable medical equipment (DME). Consistent with the definition of DME, wheeled mobility devices are typically covered by health insurance when deemed medically necessary. Despite the number of persons using wheelchairs, little knowledge is available about the types of wheelchairs provided, user's specific diagnoses and the costs associated with WMD provision.

Does the setting matter? Observing wheelchair transfers across different environmental conditions.

The setting in which wheelchair transfers are performed can affect the difficulty and the risks associated with completion. This article presents results from an observational study involving 13 wheelchair users performing independent transfers across four settings. The aim is to understand how the environment affects how different types of independent transfers are performed.

Modeling manual wheelchair propulsion cost during straight and curvilinear trajectories.

Minimizing the effort to propel a manual wheelchair is important to all users in order to optimize the efficiency of maneuvering throughout the day. Assessing the propulsion cost of wheelchairs as a mechanical system is a key aspect of understanding the influences of wheelchair design and configuration. The objective of this study was to model the relationships between inertial and energy-loss parameters to the mechanical propulsion cost across different wheelchair configurations during straight and curvilinear trajectories.

Manual wheelchair propulsion cost across different components and configurations during straight and turning maneuvers.

Aim: Maneuvering manual wheelchairs is defined by changes in momentum. The amount of effort required to maneuver a wheelchair is dependent on many factors, some of which reflect the design and configuration of the wheelchair.

Objective: The objective of this study was to measure the work required to propel a manual wheelchair configured with three weight distributions, three drive wheels and four casters.

Pressure Ulcer Risk Factors in Persons with Mobility-Related Disabilities.

Objective: To assess pressure ulcer (PU) risk in persons with mobility impairments using a large data set to identify demographic, laboratory, hemodynamic, and pharmacologic risk factors.

Methods: The cohort of interest was persons with disabilities who have mobility impairments and are diagnostically at risk of PUs. To define this cohort, diagnoses that qualify patients for skin protection wheelchair cushions were used.

Seated buttocks anatomy and its impact on biomechanical risk.

Aim: The objective of this study was to describe the amount, types, and shapes of tissue present in the buttocks during sitting (i.e., seated buttocks soft tissue anatomy), and the impact of seated buttocks soft tissue anatomy on biomechanical risk.

Measurement of rolling resistance and scrub torque of manual wheelchair drive wheels and casters.

The effort needed to maneuver a manual wheelchair is a function of the occupied wheelchair's inertia and energy loss. The primary source of energy loss is due to the resistance of the drive wheels and casters on the ground. Specifically, manual wheelchairs have two major sources of frictional energy loss: rolling resistance and scrub torque.

Everyday use of power adjustable seat height (PASH) systems.

The objective of this study was to measure how, why, and where the power adjustable seat height (PASH) system of Quantum's iLevel® wheelchairs were used. We instrumented iLevel® power wheelchairs for 24 adults to measure wheelchair occupancy, seat height, in-seat activity level, and bouts of mobility. Participants elevated their wheelchair 3.

Visualizing Tissue Strain Under the Sacrum and Coccyx in Different Supine Postures: A Case Series.

Objective: To visually assess and report the influence of supine positioning and sacrum and coccyx anatomy on tissue deformation.

Methods: A convenience sample of three participants was scanned using MRI. All participants were scanned in a supine position with a rig oriented in a flat or horizontal position and with the torso portion of the rig elevated to 30° to simulate head-of-bed elevation.

The influence of operator and wheelchair factors on wheelchair propulsion effort.

The goal of this study was to evaluate the relative influence of operator and wheelchair factors on propulsion effort during over-ground wheelchair manoeuvres. This observational study included 23 full-time manual wheelchair users and 13 able-bodied subjects. The operator factors included shoulder position, aerobic capacity and propulsion strength.