Barbara L. Shay

Relationship Between Dynamic Balance Measures and Functional Performance in Community-Dwelling Elderly People

Background Poor balance control, mobility restrictions, and fall injuries are serious problems for many older adults. Objective The purpose of this study was to evaluate a new dynamic standing balance assessment test for identifying individuals at risk for falling in a group of community-dwelling older adults. Design This was a cross-sectional observational study of 72 community-dwelling older adults who were receiving rehabilitation in a geriatric day hospital. Method A Dynamic Balance Assessment (DBA) test protocol was developed based on the concept of the Sensory Organization Test and the Clinical Test of Sensory Interaction and Balance. The DBA consists of 6 tasks performed on a normal floor surface and repeated on a sponge surface. A flexible pressure mat was used to record the foots center of pressure (COP) on both surfaces, and loss of balance was recorded. Balance performance also was evaluated using the Berg Balance Scale, the Timed “Up & Go” Test, gait speed, and the Six-Minute Walk Test. Participants were classified as “fallers” or “nonfallers” based on a self-report. Results No significant differences were noted between the faller group (n=47) and the nonfaller group (n=25) for demographic variables or medications. The DBA composite scores, which were derived from analysis of COP excursions of the 6 tasks performed on the sponge surface, were able to distinguish between fallers and nonfallers. Of the clinical tests, only the Timed “Up & Go” Test was able to differentiate between the faller and nonfaller groups. Limitations A prospective study is needed to confirm the current findings and to expand testing to a larger and more diverse sample. Conclusions The findings indicate that analysis of the extent and amount of COP displacements during selected tasks and under different surface conditions is an appropriate method to assess dynamic standing balance controls and can discriminate between fallers and nonfallers among community-dwelling elderly people.

Serotonin 5‐HT2 receptor activation induces a long‐lasting amplification of spinal reflex actions in the rat

1 C‐fibre activation induces a long‐term potentiation (LTP) in the spinal flexion reflex in mammals, presumably to provide enhanced reflexive protection of damaged tissue from further injury. Descending monoaminergic pathways are thought to depress sensory input but may also amplify spinal reflexes; the mechanisms of this modulation within the spinal cord remain to be elucidated. 2 We used electrical stimulation of primary afferents and recordings of motor output, in the rat lumbar spinal cord maintained in vitro, to demonstrate that serotonin is capable of inducing a long‐lasting increase in reflex strength at all ages examined (postnatal days 2–12). 3 Pharmacological analyses indicated an essential requirement for activation of 5‐HT2C receptors while 5‐HT1A/1B, 5‐HT7 and 5‐HT2A receptor activation was not required. In addition, primary afferent‐evoked synaptic potentials recorded in a subpopulation of laminae III‐VI spinal neurons were similarly facilitated by 5‐HT. Thus, serotonin receptor‐evoked facilitatory actions are complex, and may involve alterations in neuronal properties at both motoneuronal and pre‐motoneuronal levels. 4 This study provides the first demonstration of a descending transmitter producing a long‐lasting amplification in reflex strength, accomplished by activating a specific serotonin receptor subtype. It is suggested that brain modulatory systems regulate reflex pathways to function within an appropriate range of sensori‐motor gain, facilitating reflexes in behavioural situations requiring increased sensory responsiveness.

Functional capacity, muscle strength and falls in women with fibromyalgia ☆

BACKGROUND Patients with fibromyalgia have difficulty with activities of daily living, they exhibit reduced muscle strength and high incidence of reported falls. The objective of this study was to evaluate the functional performance and lower limb muscle strength in women with fibromyalgia and determine the relationship between muscle strength and falls. METHODS Sixteen females with fibromyalgia and 16 healthy women participated in the study. Pain intensity, fibromyalgia impact on quality of life, physical activity level and fall prevalence were assessed. The peak torque and the rate of torque development were determined in maximal voluntary isometric contraction (hip, knee and ankle joints) using a load cell. The 30s chair stand, 8 ft up and go, sit and reach, and functional reach tests were used to characterize functional performance. FINDINGS Women with fibromyalgia showed deficits in lower limb muscle strength, balance and agility and exhibited decreased knee extension peak torque and rate of torque development. In addition, they showed lower hip adduction and extension peak torque in comparison to the control group (P>0.05). Hip extension rate of torque development, duration of fibromyalgia symptoms, overall pain, knee pain, and fibromyalgia impact were strong predictors of the number of falls in patients with fibromyalgia (R2=0.86; P<0.05), when considered collectively. INTERPRETATION Women with fibromyalgia showed reduced functional performance and lower limb muscle strength, mostly explained by pain. There was a high prevalence of falls in this population, as explained by hip extensors rate of torque development, duration of fibromyalgia symptoms and pain.

The interacting effect of cognitive and motor task demands on performance of gait, balance and cognition in young adults.

Mobility limitations and cognitive impairments, each common with aging, reduce levels of physical and mental activity, are prognostic of future adverse health events, and are associated with an increased fall risk. The purpose of this study was to examine whether divided attention during walking at a constant speed would decrease locomotor rhythm, stability, and cognitive performance. Young healthy participants (n=20) performed a visuo-spatial cognitive task in sitting and while treadmill walking at 2 speeds (0.7 and 1.0 m/s).Treadmill speed had a significant effect on temporal gait variables and ML-COP excursion. Cognitive load did not have a significant effect on average temporal gait variables or COP excursion, but variation of gait variables increased during dual-task walking. ML and AP trunk motion was found to decrease during dual-task walking. There was a significant decrease in cognitive performance (success rate, response time and movement time) while walking, but no effect due to treadmill speed. In conclusion walking speed is an important variable to be controlled in studies that are designed to examine effects of concurrent cognitive tasks on locomotor rhythm, pacing and stability. Divided attention during walking at a constant speed did result in decreased performance of a visuo-spatial cognitive task and an increased variability in locomotor rhythm.

Store-and-Feedforward Adaptive Gaming System for Hand-Finger Motion Tracking in Telerehabilitation

This paper presents a telerehabilitation system that encompasses a webcam and store-and-feedforward adaptive gaming system for tracking finger-hand movement of patients during local and remote therapy sessions. Gaming-event signals and webcam images are recorded as part of a gaming session and then forwarded to an online healthcare content management system (CMS) that separates incoming information into individual patient records. The CMS makes it possible for clinicians to log in remotely and review gathered data using online reports that are provided to help with signal and image analysis using various numerical measures and plotting functions. Signals from a 6 degree-of-freedom magnetic motion tracking system provide a basis for video-game sprite control. The MMT provides a path for motion signals between common objects manipulated by a patient and a computer game. During a therapy session, a webcam that captures images of the hand together with a number of performance metrics provides insight into the quality, efficiency, and skill of a patient.

Objective evaluation of fine motor manipulation-a new clinical tool.

A new performance-based tool has been developed to accurately and precisely evaluate finger/hand function during manipulation of any object, independent of geometric and surface properties. The objectives of this study were to show test-retest reliability and evaluate criterion validity. Twenty healthy, right-handed participants were recruited. Three objects ranging in weight and size, requiring two or three fingers, were instrumented with a motion sensor that tracked 3D linear/angular motion. A computerized visual-guided tracking task was used to quantify motor performance during object manipulation. Two testing periods, one week apart were performed to evaluate test-retest reliability. Criterion validity was assessed by comparing performance with this tool to performance on commonly used clinical dexterity tests. Global performance, temporal accuracy, and amplitude consistency during manipulation of the objects compared with the reference waveform were highly reliable on the two testing occasions. Low-moderate correlations between the clinical dexterity tests and the task protocol indicate that different aspects of hand function were measured. The task protocol directly measures the ability of the hand to coordinate movement in response to a visual tracking target. Providing effective and objective ways to evaluate manual dexterity and hand function is a critical part of evidence-based practice.

Task-oriented training with computer gaming in people with rheumatoid arthritisor osteoarthritis of the hand: study protocol of a randomized controlled pilot trial.

BackgroundSignificant restriction in the ability to participate in home, work and community life results from pain, fatigue, joint damage, stiffness and reduced joint range of motion and muscle strength in people with rheumatoid arthritis or osteoarthritis of the hand. With modest evidence on the therapeutic effectiveness of conventional hand exercises, a task-oriented training program via real life object manipulations has been developed for people with arthritis. An innovative, computer-based gaming platform that allows a broad range of common objects to be seamlessly transformed into therapeutic input devices through instrumentation with a motion-sense mouse has also been designed. Personalized objects are selected to target specific training goals such as graded finger mobility, strength, endurance or fine/gross dexterous functions. The movements and object manipulation tasks that replicate common situations in everyday living will then be used to control and play any computer game, making practice challenging and engaging.Methods/DesignThe ongoing study is a 6-week, single-center, parallel-group, equally allocated and assessor-blinded pilot randomized controlled trial. Thirty people with rheumatoid arthritis or osteoarthritis affecting the hand will be randomized to receive either conventional hand exercises or the task-oriented training. The purpose is to determine a preliminary estimation of therapeutic effectiveness and feasibility of the task-oriented training program. Performance based and self-reported hand function, and exercise compliance are the study outcomes. Changes in outcomes (pre to post intervention) within each group will be assessed by paired Student t test or Wilcoxon signed-rank test and between groups (control versus experimental) post intervention using unpaired Student t test or Mann–Whitney U test.DiscussionThe study findings will inform decisions on the feasibility, safety and completion rate and will also provide preliminary data on the treatment effects of the task-oriented training compared with conventional hand exercises in people with rheumatoid arthritis or osteoarthritis of the hand.Trial registrationClinicalTrials.gov: NCT01635582

Wireless Adaptive Therapeutic TeleGaming in a Pervasive Computing Environment

This chapter introduces a wireless, pervasive computing approach to adaptive therapeutic telegaming considered in the context of near set theory. Near set theory provides a formal basis for observation, comparison and classification of perceptual granules. A perceptual granule is defined by a collection of objects that are graspable by the senses or by the mind. In the proposed pervasive computing approach to telegaming, a handicapped person (e.g., stroke patient with limited hand, finger, arm function) plays a video game by interacting with familiar instrumented objects such as cups, cutlery, soccer balls, nozzles, screw top-lids, spoons, so that the technology that makes therapeutic exercise game-playing possible is largely invisible (Archives of Physical Medicine and Rehabilitation 89:2213–2217, 2008). The basic approach to adaptive learning (AL) in the proposed telegaming environment is ethology-inspired and is quite different from the traditional approach to reinforcement learning. In biologically-inspired learning, organisms learn to achieve some goal by durable modification of behaviours in response to signals from the environment resulting from specific experiences (Animal Behavior, 1995). The term adaptive is used here in an ethological sense, where learning by an organism results from modifying behaviour in response to perceived changes in the environment. To instill adaptivity in a video game, it is assumed that learning by a video game is episodic. During an episode, the behaviour of a player is measured indirectly by tracking the occurrence of gaming events such as a hit or a miss of a target (e.g., hitting a moving ball with a game paddle). An ethogram provides a record of behaviour feature values that provide a basis a functional registry for handicapped players for gaming adaptivity. An important practical application of adaptive gaming is therapeutic rehabilitation exercise carried out in parallel with playing action video games. Enjoyable and engaging interactive gaming will motivate patients to complete the rehabilitation process. Adaptivity is seen as a way to make action games more accessible to those who have physical and cognitive impairments. The telegaming system connects to the internet and implements a feed-and-forward mechanism that transmits gaming session tables after each gaming session to a remote registry accessible to therapists and researchers. The contribution of this chapter is the introduction of a framework for wireless telegaming useful in therapeutic rehabilitation.

Serotonin alters multi-segmental convergence patterns in spinal cord deep dorsal horn and intermediate laminae neurons in an in vitro young rat preparation

&NA; Each spinal neuron has a receptive field that corresponds to stimulation of a specific area of skin or subcutaneous tissue. Receptive fields are plastic and can be altered during development and injury but the actions of neuromodulators, such as serotonin (5‐hydroxytryptamine, 5‐HT) on receptive field properties are not well known. We used stimulation of multiple adjacent dorsal root spinal segments as a measure of ‘receptive field size’ to determine the effects of 5‐HT on multi‐segmental convergent input onto neurons in laminae IV–VII. Whole‐cell patch‐clamp recordings were undertaken in the in vitro hemisected thoracolumbar spinal cord of rats aged 8–10 days old. Based on synaptic responses, neurons could be divided into two predominant groups and 5‐HT exerted different effects on these groups. The first group received excitatory post‐synaptic potentials (EPSPs) from the homonymous dorsal root but inhibitory post‐synaptic potentials (IPSPs) with increasing amplitude from more distant dorsal roots. In this group, 5‐HT preferentially depressed the IPSPs from adjacent nerve roots while leaving the EPSP intact. The second group received short‐latency EPSPs from all segments stimulated and 5‐HT potently depressed all synaptic input. In both populations the depressant actions of 5‐HT increased with dose (0.1–10.0 &mgr;M). Bicuculline and strychnine did not affect the 5‐HT induced short‐latency synaptic depression. These results suggest that descending serotonergic systems depress spinal sensory convergence in a graded and differentiated manner. The findings are discussed in relation to the modulation of nociceptive signaling.

Treatment of Chronic Low-Back Pain: A 1-Year or Greater Follow-Up

BACKGROUND Musculoskeletal disorders are the most frequent cause of physical disability in developed countries. In particular, lower back pain is very common and represents a significant burden both in terms of patient suffering and costs. It is important to determine the most effective and efficient interventions in the treatment of this condition. PURPOSE This article presents clinical outcomes in patients with chronic lower back pain involving ligamentous pathology treated by a physician who specializes in injection therapy for chronic musculoskeletal conditions and is able to tailor injection therapy specifically to each individual patient. DESIGN As a retrospective case series, patients from outpatient clinics in both rural and one urban centre were assessed, treated, and had 1 year or more follow-up. METHODS Patients were referred by their family physician for assessment for chronic lower back pain refractory to conventional medical management. OUTCOME MEASURES Pain and quality of life (QoL) numeric (10 cm) analog scales (0 = no pain, 10 = the worst pain imaginable; 0 = best quality of life, 10 = worst quality of life) were administered pretreatment and 1 year or later after the last treatment. RESULTS One hundred and ninety (190) patients were treated during the study period, June 1999-May 2006. Patients whose follow-up was 1 year or greater from the last treatment were included, leaving 140 patients available for data analysis. Both pain and QoL scores were significantly improved at least 1 year after the last treatment. There were no differences in outcomes as a result of age, response to Xylocaine (lidocaine) injection, insurance coverage, smoking history, or gender. CONCLUSIONS This study suggests that prolotherapy using a variety of proliferants can be an effective treatment for low back pain from presumed ligamentous dysfunction for some patients when performed by a skilled practitioner.