Nancy Byl

UCSF University of California, San Francisco | UCSF · Department of Physical Therapy and Rehabilitation Science

Purpose – The purpose of this paper is to evaluate the physiotherapeutic benefits of bilateral symmetric training (BST) for stroke survivors affected by hemiparesis. Design/methodology/approach – Other studies have investigated symmetric physiotherapy. A key difficulty in previous work is in maintaining mirror-imaged trajectories between the aff...

As the world's population ages, falls, physical inactivity, decreased attention and impairments in balance and gait arise as a consequence of decreased sensation, weakness, trauma and degenerative disease. Progressive balance and gait training can facilitate postural righting, safe ambulation and community participation. This small randomized clini...

Among other diminished motor capabilities, survivors of a stroke often exhibit pathological joint synergies. With respect to the upper limbs, these deficits diminish coordination in reaching, pointing, and daily task performance. Past research on pathological synergies suggests that the synergistic relationship between joints is different for flexi...

After cerebral ischemia, disruption and subsequent reorganization of functional connections occur both locally and remote to the lesion. However, the unpredictable timing and extent of sensorimotor recovery reflects a gap in understanding of these underlying neural mechanisms. We aimed to identify the plasticity of alpha-band functional neural conn...

In this paper, a network-based mobile gait rehabilitation system is proposed for improved mobility and tele-rehabilitation. In this system, an Internet-based body sensor network is employed for health monitoring and a local highspeed wireless network is developed to achieve precise control of the gait rehabilitation device, which is a compact rotar...

Robot-assisted stroke rehabilitation has become popular as one approach to helping patients recover function post stroke. Robotic rehabilitation requires four important elements to match the robot to the patient: realistic biomechanical robotic elements, an assistive control scheme enabled through the human-robot interface, a task oriented rehabili...

An emerging area of neurorehabilitation is the use of robotic devices to enhance the efficiency and effectiveness of lower extremity physical therapy post-stroke. Many of the robotic devices currently available rely on computer-driven locomotive algorithms combined with partial bodyweight-supported treadmill training that drive reflex stepping with...

The human arm has 7 degrees of freedom (DOF) while only 6 DOF are required to position the wrist and orient the palm. Thus, the inverse kinematics of an human arm has a nonunique solution. Resolving this redundancy becomes critical as the human interacts with a wearable robot and the inverse kinematics solution of these two coupled systems must be...

This article reviews current evidence on etiology, diagnosis and clinical management of patients with a challenging movement disorder referred to as focal hand dystonia (FHd). Patients who present to a rhematologist with a history of repetitive overuse, weakness, pain and involuntary, end-range posturing of the digits when performing a target task...

Conventional gait rehabilitation treatment does not provide quantitative information on abnormal gait kinematics, and the match of the intervention strategy to the underlying clinical presentation may be limited by clinical expertise and experience. Also the effect of rehabilitation treatment may be reduced as the rehabilitation treatment is achiev...

COPD is a major cause of disability, but little is known about how disability develops in this condition. The authors analysed data from the Function, Living, Outcomes and Work (FLOW) Study which enrolled 1202 Kaiser Permanente Northern California members with COPD at baseline and re-evaluated 1051 subjects at 2-year follow-up. The authors tested t...

Breast-cancer-related lymphedema affects approximately 25% of breast cancer (BC) survivors and may impact use of the upper limb during activity. The purpose of this study is to compare upper extremity (UE) impairment and activity between women with and without lymphedema after BC treatment. 144 women post BC treatment completed demographic, symptom...

Conventional gait rehabilitation treatment does not provide quantitative and graphical information on abnormal gait kinematics, and the match of the intervention strategy to the underlying clinical presentation may be limited by clinical expertise and experience. In this paper, a mobile gait monitoring system (MGMS) is proposed, which helps patient...

Purposes/Aims: Our aim is to explore the impact of BCRL on UE function. Rationale/Conceptual Basis/Background: Breast-cancer-related-lymphedema (BCRL) affects ~25% of the 2 million breast cancer survivors in the US. Its impact on upper extremity (UE) function has been understudied. The Symptom Management Model, which includes dimensions of symptom...

Previous research suggests that physical activity may have a beneficial effect on bone mineral density (BMD) in women. This relationship was explored in a 2-year, randomized, intervention trial investigating the efficacy of exercise and calcium supplementation on increasing peak bone mass in young women. One hundred and twenty-seven subjects (ages...

Pre-Post, Mixed Factorial Trial. Focal hand dystonia is a challenging movement disorder to rehabilitate in musicians and writers. To compare the neuromusculoskeletal characteristics of those with writers' cramp (WC) and musicians' cramp (MC), and evaluate responsiveness to learning-based sensorimotor training. Twenty-seven individuals (14 musicians...

Although chronic obstructive pulmonary disease (COPD) has a major impact on physical health, the specific impact of COPD on physical functional limitations has not been characterized clearly. We aimed to elucidate the physical functional limitations that are directly attributable to COPD compared to a matched referent group without the condition. W...

The authors' objective was to analyze the impact of respiratory impairment on the risk of physical functional limitations among adults with chronic obstructive pulmonary disease (COPD). They hypothesized that greater pulmonary function decrement would result in a broad array of physical functional limitations involving organ systems remote from the...

Dystonia is a disabling, involuntary disorder of movement that leads to writhing, twisting end-range movements or abnormal postures. Inadequate inhibition could account for excessive excitation and near synchronous co-contractions of agonists and antagonists. Dystonia may be generalized or specific, affecting only one part of the body or involving...

‘Repetitive strain injuries’ (RSI) Het aantal gevallen van door het werk veroorzaakte ‘repetitive strain injuries’ (rsi) neemt epidemische vormen aan. Deze letsels worden geacht de biomechanische consequenties te zijn van lang volgehouden, steeds herhaalde, krachtige bewegingen.

Patients suffering from chronic low back pain (cLBP) are often unsatisfied with conventional medical care and seek alternative therapies. Many mind-body techniques are said to help patients with low back pain by enhancing body awareness, which includes proprioception deficit in cLBP, but have not been rigorously studied in cLBP. Breath therapy is a...

Chronic or acute perinatal asphyxia (PA) has been correlated with the subsequent development of cerebral palsy (CP), a developmental neurological disorder characterized by spasticity and motor abnormalities often associated with cognitive deficits. Despite the prevalence of CP, an animal model that mimics the lifetime hypertonic motor deficits is s...

The purpose of this study was to incorporate magnetoencephalography and clinical testing to describe differences in somatosensory organization and sensorimotor function of the hand in patients with focal hand dystonia, a target-specific disorder of voluntary movement that interferes with fine motor control during the performance of rapid, repetitiv...

Focal hand dystonia (FHd) is a disabling disorder of hand control characterized by a loss of inhibition and involuntary co-contractions of agonists and antagonists that can develop in motivated, productive individuals performing highly repetitive, intensive hand tasks. It is our hypothesis that FHd can result from aberrant learning. We summarize th...

Based on the principles of neuroplasticity, the purpose of this crossover study was to determine if improvement in upper extremity (UE) function and independence could be achieved in patients 6 months to 7 years poststroke following an outpatient rehabilitation program (supervised 1.5 hours per week for 8 weeks reinforced with home gloving unaffect...

The purpose of this study was to quantify the strain of the median nerve and the ulnar nerve throughout upper-extremity positioning sequences used by clinicians to evaluate nerve dysfunction. A microstrain gauge was used to quantify strain and digital calipers were used to assess nerve excursion in 4, fresh, intact cadavers. Data analysis of noncon...

This study evaluated reliability, validity, and responsiveness of a new test of stereognosis (Byl-Cheney-Boczai Sensory Discriminator Test [BCBI]). Participants included 38 controls, 29 subjects with hand problems, and 3 raters. With eyes closed, after sweeping the digit over a design (10 mm x 10 mm) embedded in a plastic cube (13 mm x 13 mm), subj...

Phase II cardiac rehabilitation programs are associated with improvements in exercise tolerance, coronary risk factors, and psychosocial well-being. Nevertheless, previous reports have generally evaluated the global effectiveness of these programs (ie, on all subjects, collectively), which may serve to camouflage or attenuate the impact of these in...

Motor, and Cognitive Skill Development: Implications for Neurorehabilitation Consequences of “Ministrokes” Induced in these Cortical Zones A Different View of the Origins of Human Disability Origins and Therapeutic Remediation of Specific Language Impairments A Language-Impaired Child is a Specialist at a Particular Form of Language Processing Othe...

Dystonia is a movement disorder characterized by sustained muscle contractions leading to twisting movements and abnormal postures (Fahn, 1988). It is usually assumed that dystonia is driven by abnormal activity arising in the basal ganglia (Marsden et al., 1985; Hallett, 1997; Vitek et al., 1998). Additionally, there is indirect evidence that neur...

Recent studies show that rapid, nearly simultaneous, stereotypical repetitive fine motor movements can degrade the sensory representation of the hand and lead to a loss of normal motor control with a target task, referred to as occupational hand cramps or focal hand dystonia. The purpose of this prospective follow-up study was to determine whether...

Focal hand dystonia is a disabling, involuntary disorder of movement that can disrupt a successful musician's career. This problem is difficult to treat, to some extent because we do not fully understand its origin. Somatosensory degradation has been proposed as one etiology. The purpose of this case study was to compare the differences in the soma...

A wide range of observations suggest that sensory inputs play a significant role in dystonia. For example, the map of the hand representation in the primary sensory cortex (area 3b) is altered in monkeys with dystonia-like movements resulting from overtraining in a gripping task. We investigated whether similar reorganization occurs in the somatic...

The majority of research on distal radius fractures consists of retrospective, descriptive studies of patients with unstable fractures requiring fixation. The purpose of this investigation was to report on impairments in flexibility, grip strength, and motor control and on the presence of swelling and atrophy immediately after cast immobilization o...

Repetitive strain injuries are thought to result from biomechanical stress and tissue microtrauma. The purpose of this study was to investigate the presence of local inflammation, scarring or anatomical variations of the flexor tendons and the median and ulnar nerves in four Owl monkeys behaviorally trained at a repetitive motor or sensory task. Th...

This paper concerns the characterization of performance and perceptual learning of somatosensory interval discrimination. The purposes of this study were to define (1) the performance characteristics for interval discrimination in the somatosensory system by naive adult humans, (2) the normal capacities for improvement in somatosensory interval dis...

The symptoms of myasthenia gravis (MG) are often simply classified as excessive fatigue rather than evaluated as different signs of disease progression. The purpose of this study was to evaluate the medical symptoms of patients with MG who had been under treatment for many years. Patients diagnosed with MG were compared to healthy controls. A surve...

Adult humans were unilaterally trained in a tactile discrimination task of sequentially applied multi-finger stimuli. Magnetic source imaging (MSI) was performed before and after the training to evaluate use-dependent neuronal plasticity. All subjects showed fast improvements in performance and complete transfer of the learned task. MSI recordings...

Sporadic research reports of decreased proprioception and balance problems have been reported in subjects with idiopathic scoliosis, yet these sensory motor deficits have not been addressed in conservative clinical management programs. The purpose of this study was to compare both balance reactions and vibratory sensitivity (as an estimate of propr...

To determine whether there is a complex sensory disturbance that may be contributing to the motor deficit in patients with Parkinson disease. Comparison of performance by patients and healthy, age- and sex-matched subjects in tests of various sensory functions. The Center for Human Performance and Testing at a university hospital and research cente...

Repetitive strain injuries (RSIs) are difficult to treat. Some individuals with RSIs may ultimately develop chronic pain syndromes or movement problems like focal hand dystonia (FDh), a disorder of motor control manifested in a specific context during skilled, hand tasks. This paper reports on the results of four neuroplasticity studies suggesting...

Job-related repetitive strain injuries (RSIs) are increasing, and current treatment strategies often fail to return injured people to work. This study documented the neural consequences of using two different movement strategies for active, repetitive hand closing and opening. Two owl monkeys were trained for 20 weeks to repetitively close a handpi...

The purpose of this methodological study was to evaluate the reliability, internal consistency, and sensitivity of a new self-report functional outcomes profile, the California Functional Evaluation 40 (CAFE 40). The CAFE 40 contains 3 sections: 1. Section 1 General health and activity level rated on an ordinal scale; 2. Section II: Independence- a...

In this study we tested a neuroplasticity/learning origins hypothesis for repetitive strain injuries (RSIs), including occupationally induced focal dystonia. Repetitive movements produced in a specific form and in an appropriate behavioral context cause a degradation of the sensory feedback information controlling fine motor movements, resulting in...

Some individuals with repetitive strain injury (RSI) develop focal dystonia of the hand (FDh), a disorder of motor control manifested in a specific context during skilled, hand movements. This descriptive study was designed to determine if musicians with FDh had reduced tactile discrimination. Ten healthy adults and ten patients with FDh participat...

Repetitive strain injuries are reaching epidemic levels among workers who perform heavy schedules of rapid alternating movements (eg., computer programmers, data entry workers) or repetitive, sustained, coordinated movements (eg., editors, writers, salespeople). The purpose of this study was to determine if patients with repetitive strain injury de...

Phonophoresis is the use of ultrasound (US) to enhance the delivery of topically applied drugs. The purposes of this article are (1) to review the basic principles of transcutaneous drug delivery, (2) to summarize the functional anatomy of the skin pertinent to phonophoresis, (3) to outline the physiological principles of US as an enhancer of topic...

Microamperage direct current and microamperage electromagnetic stimulation are used to accelerate healing in bone. Although many clinicians are using microamperage stimulation to relieve pain and facilitate wound healing, there is significant question regarding whether this low-intensity direct current significantly accelerates soft tissue wound re...

We appreciate the careful review of the commentators regarding our study and the study by Leffmann and colleagues, both studying the effects of pulsed, direct microcurrent stimulation on the acceleration of normal wound healing. Both Dr Snyder-Mackler and Dr Robinson recognized the degree of control applied to both of these studies, and both commen...

Arts medicine has come of age, resulting from 3 important developments over the past decade: improved methods of diagnosis and treatment, an awareness that artists suffer from special problems related to their occupation and lifestyle, and the establishment of health programs emphasizing an interdisciplinary approach to these patients. We focus on...

Although physical therapists and physicians often treat patients with local musculoskeletal inflammation using topically applied steroids enhanced with ultrasound, there is a paucity of research confirming that phonophoresis significantly enhances drug diffusion. The purpose of this study was to determine if ultrasound enhances the diffusion of tra...

Ultrasound is commonly used by physical therapists, but there is no consensus regarding the most effective therapeutic dose for accelerating healing of open or closed wounds. A controlled, single-blind, posttest experimental study was carried out to compare differences in wound breaking strength and collagen deposition [hydroxyproline (HoPro)]. For...

We measured simple and complex balance responses with a force plate stabiliometer in 70 adolescents: 50 with idiopathic scoliosis (IS) and 20 controls. In stable static balance positions, the two groups performed similarly, but when the visual and somatosensory systems were challenged simultaneously, the IS group had a significantly higher mean bod...

This study reports on the effect of low-dose ultrasound in accelerating wound healing in matched pairs of surgically induced incisions and full-thickness and partial-thickness lesions in 11 Yucatan mini-pigs after 7 days of healing and 5 days of sonation. Tensile strength, collagen deposition (hydroxyproline), reduction in wound size (full-thicknes...

An unexplained loss of muscle strength occurs with aging. Vitamin D deficiency can cause myopathy and administration of 1,25-dihydroxyvitamin D3 [1,25-(OH2)D3] to persons with low serum concentrations can improve strength. To test the hypothesis that the weakness associated with aging is in part due to inadequate serum concentrations of [1,25-(OH2)...

There is a lack of information on the reliability of devices used to test trunk flexor and extensor strength. In this study, the short-term reliability of two isokinetic muscle performance testing devices was assessed. Measurements of knee flexion/extension and trunk flexion/extension were made in 15 normal subjects (mean age, 29.9 years). Determin...

Form rotation, figure directionality, and figure-ground discrimination were evaluated before and after 10 days of vestibular or aerobic exercises for 30 boys (7 to 12 yr.) who showed problems in learning, reading, and inattention. Eight subjects had normal vestibulo-ocular reflex (VOR) responses as determined by caloric and rotational testing. They...

This study reports the intrarater and interrater reliability of measurements for elbow flexion (biceps) and shoulder abduction (deltoid) in 27 normal subjects. Testing was done by two physical therapy examiners. For each muscle group tested, the first series of three tests were administered according to the general guidelines described in the dynam...

In July 1975, the Division of Ambulatory and Community Medicine at the University of California, San Francisco, initiated an interdisciplinary team education program as part of a required core medical clerkship in primary care. Significant emphasis was placed on evaluation of student and patient service outcomes. Overall, students rated the teachin...

To teach the concepts of rehabilitation to undergraduates in a clinical, primary-care setting, it is essential to first mobilize student awareness regarding patient dysfunction. After some sensitivity has developed, faculty can focus on rehabilitation theories and processes. This method of teaching is generally accepted positively by students. A da...

At least 30 per cent of the patients seen in an out-patient primary care setting have health problems related to their work. Some of these patients require special attention. Resolution of both the medical and the work problems is essential because of the strong interrelationship. In one particular setting, an interdisciplinary team was formulated...

A three-year study was undertaken in the general medical clinic of a private community hospital, to assess the health behavior, health status, and profile of function of stable chronic disease was developed and tested. It was shown that these patients used a disproportionate amount of health care services. Half of the group was treated by a nurse p...

Little is known about patients who chronically express work problems through medical complaints or who develop or exaggerate physical problems to avoid work, the authors say. In 1973 a university-affiliated medical clinic set up a multidisciplinary work clinic to study and treat patients with work-related health problems. In general the clinic's fi...

This prospective, correlational study sought to identify a clini- cally feasible, valid measure of taxane-induced peripheral neuropathy that correlated with impairments in balance, physical performance, pain, and quality of life (QOL). In all, the study included 20 breast can- cer patients who completed taxane chemotherapy and 20 healthy women who...

Typescript. Thesis (Ph. D.)--University of California, Berkeley, with San Francisco State University. Includes bibliographical references (leaves 230-258).