Lars Ingimar Eugen Oddsson

University of Minnesota Twin Cities | UMN · Technological Leadership Institute (TLI)

Foot sole somatosensory impairment associated with peripheral neuropathy (PN) is prevalent and a strong independent risk factor for gait disturbance and falls in older adults. Walkasins, a lower-limb sensory prosthesis, has been shown to improve gait and mobility in people with PN by providing afferent input related to foot sole pressure distributi...

Background We recently reported that individuals with impaired plantar sensation and high fall risk due to sensory peripheral neuropathy (PN) improved gait and balance function following 10 weeks of use of Walkasins ® , a wearable lower limb sensory prosthesis that provides directional specific mechanical tactile stimuli related to plantar pressure...

Background We recently reported that individuals with impaired plantar sensation and high fall risk due to sensory peripheral neuropathy (PN) improved gait and balance function following 10 weeks of use of Walkasins ® , a wearable lower limb sensory prosthesis that provides directional tactile stimuli related to plantar pressure measurements during...

Background Mounting evidence suggests that wearable technologies using peripheral neuromodulation can provide novel ways of improving mobility and gait function in various patient populations including older adults. The purpose of this narrative review is to provide an overview of wearable technologies/devices to improve mobility and gait function...

Foot sole somatosensory impairment associated with peripheral neuropathy (PN) is prevalent and a strong independent risk factor for gait disturbance and falls in older adults. A lower-limb sensory prosthesis providing afferent input related to foot sole pressure distributions via lower-leg vibrotactile stimulation has been demonstrated to improve g...

Background: Peripheral neuropathy (PN) can result in either partial or complete loss of distal sensation resulting in an increased fall risk. Walkasins® uses a shoe insert to detect the magnitude and direction of sway and sends signals to a leg unit that provides sensory balance cues. The objective of this case report is to describe the long-term i...

Astronauts experience post-flight disturbances in postural and locomotor control due to sensorimotor adaptations during spaceflight. These alterations may have adverse consequences if a rapid egress is required after landing. Although current exercise protocols can effectively mitigate cardiovascular and muscular deconditioning, the benefits to pos...

Background: Sensory peripheral neuropathy (PN) is associated with gait, balance problems and high fall risk. The walk2Wellness trial investigates effects of long-term, home-based daily use of a wearable sensory prosthesis on gait function, balance, quality of life and fall rates in PN patients. The device (Walkasins®, RxFunction Inc., MN, United S...

Background:Peripheral neuropathy (PN) can result in either partial or complete loss of distal sensation resulting in an increased fall risk. Walkasins® uses a shoe insert to detect the magnitude and direction of sway and sends signals to a leg unit that provides sensory balance cues. The objective of this case report is to describe the long-term in...

Background: Patients with sensory peripheral neuropathy (PN) commonly present with gait and balance problems increasing their risk of falls. The multi-site walk2Wellness trial investigates effects of long-term, home-based daily use of a wearable lower limb sensory neuroprosthesis on gait function, balance, quality of life and fall rates in a cohort...

Peripheral neuropathy may cause loss of sensory information from plantar cutaneous mechanoreceptors that is important for balance control and falls management. The current study investigated short-term effects of using Walkasins, an external lower-limb sensory neuroprosthesis, on clinical outcomes of balance and gait in persons who reported periphe...

IRB-approved protocol. (DOCX)

Minimal data underlying study results. (XLSX)

CONSORT_2010_Checklist. (DOC)

Supporting body weight and balance control are foundations of our ability to move and function independently. However, neurological disease, injury, and aging often threaten these prerequisites of functional independence, leading to a decrease in quality of life. In the United States alone, 7.5 million individuals have survived stroke, traumatic br...

Multisensory - visual, vestibular, and somatosensory information is integrated for appropriate postural control. The primary goal of this study was to assess somatosensory utilization during a functional motor task of unipedal postural control, in normal healthy adults. Assessing individual bias in the utilization of individual sensory contribution...

Peripheral neuropathy (PN), commonly caused by diabetes mellitus, is a debilitating condition that currently affects approximately 20 million Americans. Chronic symptoms of PN often involve pain and weakness of the lower limbs, with eventual sensation loss on the plantar surfaces of the feet. According to epidemiological studies, reduced foot sole...

Although much research has been done on repetitive transcranial magnetic stimulation (rTMS) in chronic stroke, only sparse research has been done in acute stroke despite the particularly rich potential for neuroplasticity in this stage. We attempted a preliminary clinical trial in one active, high-quality inpatient rehabilitation facility (IRF) in...

The study evaluated the effect of 4 weeks of combined resistance-balance training and resistance training alone in a 90° tilted environment on muscle power. Two groups of healthy young subjects performed leg extensions while in a supine position, either on a firm surface along a linear track or on an unstable surface requiring mediolateral balancin...

Objective: To evaluate long-term effects of balance-training on concerns about falling, gait, balance performance, and physical function in older adults with osteoporosis and increased risk of falling. Design: Randomized controlled trial, including three groups (training, training+physical activity, and control group), with follow-ups at three, nin...

Obesity is one of the most significant epidemiological trends of the last decades. Recently it was found that obese individuals show postural instability. Balance control mechanisms in obese older adults were less studied. Therefore we aimed to investigate the effect of obesity on balance control mechanisms in older adults. Parameters from Stabilog...

Evidence-based guidelines recommend early functional rehabilitation of stroke patients when risk of patient harm can be managed. Current tools do not allow balance training under load conditions sufficiently low for acute stroke patients. This single-arm pilot study tested feasibility and safety for acute stroke survivors to use “Balance-Bed”, a te...

Objective: To evaluate long-term effects of balance-training on concerns about falling, gait, balance performance, and physical function in older adults with osteoporosis and increased risk of falling. Design: Randomized controlled trial, including three groups (training, training+physical activity, and control group), with follow-ups at three,...

A sensory data integration system for integrating sensory data generated by a first sensory substitution device and sensory data generated by a second sensory substitution device. The system includes a processor configured to generate an orientation signal indicative of a difference between a subject's orientation and an acceptable orientation. The...

Although significant progress has been achieved in developing sensory augmentation methods to improve standing balance, attempts to extend this research to locomotion have been quite limited in scope. The goal of this study was to characterize the effects of two real-time feedback displays on locomotor performance during four gait-based tasks rangi...

Improving adherence to therapy is a critical component of advancing outcomes and reducing the cost of rehabilitation. A robotic platform was previously developed to explore how robotics could be applied to the social dimension of rehabilitation to improve adherence. This paper aims to report on feedback given by end users of the robotic platform as...

Objective: To evaluate the long-term effects of a progressive and specific balance group-based program in healthy elderly individuals with increased risk of falling. Design: Follow-up of a randomized controlled trial at nine and 15 months on a population that has previously been described at three months. Setting: The study was conducted in St...

Sensory substitution devices can provide body orientation and somatosensory information through vibrotactile feedback. This pilot study compares the effects of two vibrotactile feedback devices during a locomotor task using similar groups of elder subjects.

Objectives: To evaluate the effect of a group-based functional and specific balance training programme that included dual-task exercises on balance function in healthy older adults. Design: A single-blind randomized controlled trial. Setting: General community. Participants: Sixty-six community-dwelling older adults (age 77.0 ± 6.5 years), w...

Given the known deficits in attention in attention deficit hyperactivity disorder (ADHD) and the evidence suggesting that postural control requires attention, this study aimed to investigate the mechanisms of postural control of children with and without ADHD in single-(ST) and dual-task (DT) conditions. Postural sway and stabilogram diffusion anal...

Previous studies have demonstrated that ankle muscle fatigue alters postural sway. Our aim was to better understand postural control mechanisms during upright stance following plantar flexor fatigue. Ten healthy young volunteers, 25.7±2.2 years old, were recruited. Foot center-of-pressure (CoP) displacement data were collected during narrow base up...

A cross-sectional retrospective study of parameters reflecting balance function in elderly fallers and non-fallers was conducted to better understand postural control mechanisms in individuals prone to falls. Ninety-nine old adults (65-91 years, mean age 78.4 (SD 5.7)) from two self-care residential facilities participated in the study. Foot center...

This study investigated the force-time relationship during the push-off stage of a rapid voluntary step in young and older healthy adults, to study the assumption that when balance is lost a quick step may preserve stability. The ability to achieve peak propulsive force within a short time is critical for the performance of such a quick powerful st...

Many older people fall when they perform tasks which require increased attention. The aim of this study was to determine differences in reaction times, during simple-, dual- and triple-task conditions requiring differing levels of motor coordination, balance control and cognitive attention, between groups of fallers and non-fallers in community-dwe...

Stepping reactions play a critical role in responding to balance perturbations, whether they are a consequence of external perturbation or self-induced in nature. The aim of the present study was to determine prospectively the capacity of voluntary stepping performance in singleand dual-task conditions, to predict future falls among older community...

[Purpose] Examine the age-related deterioration of attentional capacity and predictive validity of multi-tasking performances for falls in adults aged 75 and older. [Methods] This study involved 45 elderly individuals and 15 healthy and young volunteers. Reaction times to a visual stimulus were measured under three different conditions: 1) stepping...

Creating product innovations involves the need to understand the social context in which the innovation is created and ultimately the context in which it is to be used. The use of globally distributed teams (GDTs) in engineering education to understand and enhance the social and technological interaction could catalyze the process of creating innov...

Quick step execution may prevent falls when balance is lost; adding a concurrent task delays this function. We investigate whether push-off force-time relations during the execution of rapid voluntary stepping is affected by a secondary task in older and young adults. Nineteen healthy older adults and 12 young adults performed rapid voluntary stepp...

Well-known difficulties of making patients adhere to assigned treatments have made engineers and clinicians look towards technology for possible solutions. Recent studies have found that cell phone-based text messaging can help drive positive changes in patients' disease management and preventive health behavior. Furthermore, work in the area of as...

To investigate voluntary step behavior of chronic stroke survivors during single- and dual-task conditions and compare the results to healthy age- and sex-matched controls. Case-control. Laboratory-based study. Chronic stroke survivors (n=16) and healthy controls (n=16). Not applicable. Forward and backward rapid voluntary stepping were performed a...

Interdisciplinary settings have been highlighted for creative user-close development of products and services. Similarly, user involvement in the actual design process has been presented as a way to make attractive products that will earn market shares. But will an interdisciplinary setting in itself generate the beneficial spin-offs we expect? Wil...

The trunk is frequently modelled as one fixed segment ignoring possible multi-segmental contributions during manual handling. This study compared segmental trunk motion in a young and older population during a lifting task. Twelve elderly and 19 young subjects repeatedly lifted a 5 kg box from bench to shelf under two stance conditions. Displacemen...

We compared the mediolateral (M/L) responses to perturbations during locomotion of vestibulopathic (VP) subjects to those of controls. Eight subjects with unilateral vestibular loss (100% Reduced Vestibular Response from the caloric test) resulting from surgery for vestibular schwannoma and 11 controls were selected for this study. Despite their kn...

Falls are the most common cause of injuries and the primary etiology for accidental deaths in the elderly population. The ability to quickly take a step is of paramount importance in maintaining balance. Previous research has shown a significant correlation between the time it takes to execute a step and the risk of experiencing a future fall. Cons...

Gait and balance impairments may increase the risk of falls, the leading cause of accidental death in the elderly population. Fall-related injuries constitute a serious public health problem associated with high costs for society as well as human suffering. A rapid step is the most important protective postural strategy, acting to recover equilibri...

Single-axis vibrotactile feedback of trunk tilt provided in real-time has previously been shown to significantly reduce the root-mean-square (RMS) trunk sway in subjects with vestibular loss during single-axis perturbation. This research examines the effect of multi-directional vibrotactile feedback on postural sway during continuous multi-directio...

To assess the use of the Voluntary Step Execution Test to identify fallers. Cross-sectional retrospective. Two self-care, residential facilities. Participants: a total of 100 healthy old volunteers (mean age = 78.4 +/- 5.7). The study investigated the use of the Voluntary Step Execution Test to identify fallers under single and dual-task conditions...

Most balance training regimens for elderly individuals focus on self-controlled exercises, although automatic postural responses after a balance perturbation are not under direct volitional control. We critically review the literature on this topic, and notice that several studies fail to comply with basic principles of training and therefore show...

There is a need for effective and early functional rehabilitation of patients with gait and balance problems including those with spinal cord injury, neurological diseases and recovering from hip fractures, a common consequence of falls especially in the elderly population. Gait training in these patients using partial body weight support (BWS) on...

The current study investigated the repeatability (test-retest reliability) of ground reaction force parameters recorded during a voluntary step execution under single (motor task) and dual task (motor and cognitive task) conditions for healthy adults and elderly individuals as well as the number of trials required to produce repeatable results. Twe...

The current project is driven by the need for effective and functional treatment of various categories of patients with gait and balance problems. Furthermore, early treatment and mobilization of patients with hip fractures, a common consequence of falls especially in the elderly population, is critical for a successful outcome. Gait training in th...

To investigate voluntary step behavior of healthy elderly individuals during single- and dual-task conditions and to compare it with those of young subjects. Laboratory-based study. Tests of healthy elderly and young individuals from senior community centers and from the university population in Boston, Massachusetts. Sixty-six elderly and 12 young...

There is considerable evidence that lower-limb somatosensation contributes to the control of upright balance. In this study, we investigated the specific role of foot sole cutaneous afferents in the generation of balance corrections following lateral accelerations of the support surface. Participants were subjected to balance perturbations before a...

OBJECTIVES: To investigate voluntary step behavior of healthy elderly individuals during single- and dual-task conditions and to compare it with those of young subjects. DESIGN: Laboratory-based study. SETTING: Tests of healthy elderly and young individuals from senior community centers and from the university population in Boston, Massachusetts. P...

Considerable evidence shows that sensation from the feet and ankles is important for standing balance control. It remains unclear, however, to what extent specific foot and ankle sensory systems are involved. This study focused on the role of plantar cutaneous sensation in quasi-static balance control. Iontophoretic delivery of anesthesia was used...

The aim of the current study was to develop a safe, standardized, stability test and to explore a set of metrics to characterize the recovery of gait stability in healthy individuals following a single mechanical perturbation during steady locomotion. Balance perturbations were mechanically applied to the right foot of 12 healthy subjects during pa...

Body-mounted motion sensors have been shown to decrease subject sway when a tilt estimate is fed back to the user by means of an array of tactile vibrators which display estimated tilt magnitude and direction. Vestibulopathic subjects who are tested using computerized dynamic posturography show significantly reduced sway in both the sensory motor a...

In studies of sensory contributions to motor control, it may be advantageous to temporarily reduce the sensitivity of specific sensory systems. This article details a method for non-invasively inducing cutaneous anesthesia, leaving proprioceptive and motor functions intact. This method, called alternating-pulse iontophoresis, differs from conventio...

Paraspinal electromyographic (EMG) activity was recorded bilaterally from three lumbar levels during 30-s isometric trunk extensions [40 and 80% of maximum voluntary contraction (MVC)] in 20 healthy men and 14 chronic low back pain patients in pain. EMG parameters indicating neuromuscular fatigue and contralateral imbalances in EMG root-mean-square...

Any voluntary motion of the body causes an internal perturbation of balance. Load transfer during manual material handling may increase these perturbations. This study investigates effects of stance condition on postural control during lifting. Nineteen healthy subjects repeatedly lifted and lowered a load between a desk and a shelf. The base of su...

The purpose of the study was to explore whether a relationship existed between subject's experience and objective measurements of back-muscle fatigue in healthy subjects. This may be used as reference material later. Muscle fatigue in the lower back was measured in healthy subjects using a staircase protocol. Muscle fatigue measurement in the lower...

We compared the mediolateral (M/L) responses to perturbations during locomotion of vestibulopathic (VP) subjects to those of controls. Eight subjects with unilateral vestibular loss (100% Reduced Vestibular Response from the caloric test) resulting from surgery for vestibular schwannoma and 11 controls were selected for this study. Despite their kn...

Although low back pain (LBP) is a widespread and disabling health problem, there is a lack of evidence based medicine with respect to its treatment and rehabilitation. A major reason for this is the poor understanding of the underlying mechanisms of the LBP syndromes. In an attempt to fill this gap, the present review article provides an overview o...

Interaction between voluntary and postural motor commands during perturbed lifting [Spine 1999;26(6):545-52]

An experimental study was conducted to evaluate the effect of an unexpected postural perturbation during a lifting task. To investigate electromyographic responses in the erector spinae to a postural perturbation, simulating slipping, during an ongoing voluntary lifting movement. It was hypothesized that specific combinations of voluntary movement...