ORCID Profile
0000-0002-3573-3859
Current Organisations
Vanderbilt University Medical Center
,
University of Iowa
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
Publisher: Elsevier BV
Date: 2009
DOI: 10.1016/J.SPINEE.2008.07.007
Abstract: Pain and disability after lumbar fusion surgery contributes to the over $20 billion dollars spent in health-care costs and estimated $28 billion in lost wages annually. With the goal of returning to work, an intensive program designed to build functional strength may be used. Previous interventions for this subgroup report the outcome measure of return to work (RTW), but do not account for the physical demand of the job to which they are returning. This may account for varying RTW and re-injury rates. To examine the effectiveness of a sports performance-based work conditioning/hardening (SPWC/H) program on increasing an in idual's strength measured by achievement of physical demand level (PDL) job classification of in iduals followed by workers' compensation having had lumbar fusion surgery. An uncontrolled multicenter, retrospective observational study of visits from 1999-2002 in an outpatient physical therapy setting. Fifty-four patients having undergone lumbar fusion surgery, managed by workers' compensation, that successfully completed a SPWC/H program. Physiologic measures: Deadlift and overhead press lifts, defined as maximum weight, a patient is able to lift between 8 and 15 repetitions. Functional measures: Calculated deadlift and overhead press volume (DLv, OHv) and estimated one repetition maximum (DLm, OHm). Physical demand level (PDL) for first (pre) and last week (post) are defined as: light (L 20lb occasionally), medium (M, 50lb occasionally), medium heavy (MH, 75lb occasionally), heavy (H, 100lb occasionally), and very heavy (VH>100lb occasionally), where 'occasionally' for the purposes of this article, is defined as in the 8-15 repetition range. Patients completed a greater than or equal to 4 week, 4-5 days/wk, SPWC/H program. This program combines traditional concepts of strength and endurance training of work conditioning (WC) and hardening (WH) programs, with the sports performance concept of periodization in resistance training volume and intensity. Best set overhead and press lifts were obtained from each patient during the first and last week of the program. Significant increase between pre- and post-DLv, DLm, OHv, and OHm (all p<0.0001) existed when grouping all subjects. When adjacent groups are merged into M/MH and H/VH, significant differences existed between groups and pre- and postlifts (p<0.05). There was a median increase of three classifications when grouping by pre-PDL. There was no difference in outcomes found by grouping by single or multiple levels fused. Overall, numbers in each starting PDL were: 41 (75.9%) light, 6 (11.1%) LM, and 7 (13%) in medium. Numbers ending in each PDL group were: 1 (1.9%) light, 2 (3.7%) LM, 7 (13%) medium, 19 (35.2%) medium/heavy, 5 (9.3%) heavy, and 20 (37%) at very high. Post-lumbar spinal fusion patients are typically at the light PDL (<20lb occasionally) on completion of traditional physical therapy program. After an SPWC/H program, significant increase strength of deadlift and overhead lift volume and one repetition maximum demonstrated a median three-level increase in classification of PDL. We were also able to determine that there was no difference in strength outcome between those with a single- vs. multiple-level fusion surgery. Although the vast majority of in iduals entered the program at the lowest PDL (20lb or less occasionally), more than 80% of patients completed the program at PDL of medium (50lb occasionally) or above, and 37% of patients achieved the maximum PDL (over 100lb occasionally). Future studies are needed to determine if increases in strength determined by PDL classification such as these relates to increased RTW rates and decreased re-injury rates.
Publisher: Informa UK Limited
Date: 02-01-2019
Publisher: Elsevier BV
Date: 02-2021
Publisher: SAGE Publications
Date: 04-01-2023
DOI: 10.1177/00315125221149147
Abstract: An adaptive response to unexpected perturbations requires near-term and long-term adjustments over time. We used multifractal analysis to test how nonlinear interactions across timescales might support an adaptive response following an unpredictable perturbation. We reanalyzed torque data from 44 young and 24 older adults who performed a single-leg squat task challenged by an unexpected mechanical perturbation and a secondary visual-cognitive task. We report three findings: (a) multifractal nonlinearity interacted with pre-perturbation torque production and task error to presage greater pre-voluntary feedforward increases and greater voluntary reductions, respectively, in post-perturbation task error (b) multifractal nonlinearity presaged relatively smaller task error than standard deviations of both pre-perturbation torques and pre-perturbation task error and (c) increased task demand (e.g., age-related changes in dexterity and dual-task settings) led to multifractal nonlinearity presaging reduced task error. All these results were consistent with our expectations, except that a pre-perturbation knee torque-dependent increase in post-perturbation task error appeared later for older than for younger participants. This correlational multifractal modeling offered theoretical clarity on the possible roles of nonlinear interactions across timescales, moderating both feedforward and feedback processes, and presaging greater stability when the standard deviation is relatively large and task demands are strong. Thus, multifractal nonlinearity usefully describes movement variability even when paired with classical descriptors like the standard deviation. We discuss potential insights from these findings for understanding suprapostural dexterity and developing rehabilitative interventions.
Publisher: Elsevier BV
Date: 2005
DOI: 10.1016/J.CLINPH.2004.07.019
Abstract: To estimate the processing time and neuromuscular delay required to extract and process sensory information from the ankle in order to coordinate an upper extremity movement sequence. Nineteen able-bodied subjects were tested on their ability to perform a motor task that involved extension of their left index finger when their left ankle was passively plantar flexed at random velocities through a predetermined target angle. We found that the able-bodied subjects were able to adjust their finger responses up to ankle velocities of 70 degrees /s (300 ms). Reaction time, defined as the delay between onset of ankle rotation and how quickly the index finger could be extended, was 215 ms. The processing time and conduction delay was estimated to be approximately 85 ms. These results indicate that the nervous system processes kinesthetic input related to joint rotation of the ankle with the central mechanisms to execute a planned coordinated task with the upper extremity. The time required to process proprioceptive information from the leg to perform a coordinated task with the upper extremity may vary throughout the lifespan. Understanding the effects of age, exercise, or injury on proprioceptive processing time may have important clinical implications.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 25-09-2019
DOI: 10.1519/JPT.0000000000000244
Abstract: Executive function in normal aging may be modulated by body habitus and adiposity, both factors modified by physical therapist prescriptions. This study measured between-day reliability of executive function metrics in young and older in iduals and examined associations between cognition, adiposity, and physical activity. Forty-three young and 24 older participants underwent executive function assessment via the National Institutes of Health Toolbox Cognition Battery (Dimensional Change Card Sort, Flanker Inhibitory Control and Attention [Flanker], and List Sorting Working Memory [List Sorting]) at 7-day intervals. Between-day reliability was assessed via intraclass correlation (ICC). Responsiveness was assessed via between-day effect size and Cohen's d . Forward stepwise linear regression examined associations between cognition and age, body mass index, percent body fat, and a self-report measure of physical activity (International Physical Activity Questionnaire Short Form). Executive function scores were higher for young participants than for older participants (all P .002), consistent with typical age-related cognitive decline. Reliability of cognitive metrics was higher for older participants (ICC = 0.483-0.917) than for young participants (ICC = 0.386-0.730). Between-day effect sizes were approximately 50% smaller for older participants. Percent body fat significantly correlated with the Flanker Unadjusted Scale ( P = .004, R 2 = 0.0772). Neither vigorous nor total physical activity correlated with any cognitive metric. Older participants demonstrated greater between-day reliability for executive function measures, while young participants showed greater capacity to improve performance upon repeat exposure to a cognitive test (especially Flanker). Percent body fat correlated significantly with Flanker scores, while body mass index (an indirect measure of body fat) did not. Self-reported physical activity did not correlate with executive function. Cognitive response to physical therapist–prescribed exercise is a fertile ground for future research.
Publisher: Journal of Orthopaedic & Sports Physical Therapy (JOSPT)
Date: 07-2005
Publisher: Elsevier BV
Date: 02-2017
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 05-2015
Publisher: American Physiological Society
Date: 11-2006
DOI: 10.1152/JAPPLPHYSIOL.00385.2006
Abstract: Chronically paralyzed muscle requires extensive training before it can deliver a therapeutic dose of repetitive stress to the musculoskeletal system. Neuromuscular electrical stimulation, under feedback control, may subvert the effects of fatigue, yielding more rapid and extensive adaptations to training. The purposes of this investigation were to 1) compare the effectiveness of torque feedback-controlled (FDBCK) electrical stimulation with classic open-loop constant-frequency (CONST) stimulation, and 2) ascertain which of three stimulation strategies best maintains soleus torque during repetitive stimulation. When torque declined by 10%, the FDBCK protocol modulated the base stimulation frequency in three ways: by a fixed increase, by a paired pulse (doublet) at the beginning of the stimulation train, and by a fixed decrease. The stimulation strategy that most effectively restored torque continued for successive contractions. This process repeated each time torque declined by 10%. In fresh muscle, FDBCK stimulation offered minimal advantage in maintaining peak torque or mean torque over CONST stimulation. As long-duration fatigue developed in subsequent bouts, FDBCK stimulation became most effective (∼40% higher final normalized torque than CONST). The high-frequency strategy was selected ∼90% of the time, supporting that excitation-contraction coupling compromise and not neuromuscular transmission failure contributed to fatigue of paralyzed muscle. Ideal stimulation strategies may vary according to the site of fatigue this stimulation approach offered the advantage of online modulation of stimulation strategies in response to fatigue conditions. Based on stress-adaptation principles, FDBCK-controlled stimulation may enhance training effects in chronically paralyzed muscle.
Publisher: Informa UK Limited
Date: 20-06-2018
Publisher: BMJ
Date: 02-2022
DOI: 10.1136/BMJOPEN-2021-049560
Abstract: The concept of this review is to examine and quantify the reporting of parameters of dose (duration, speed, head excursion) and dosage (daily and weekly frequency, duration) for gaze stabilisation exercises and to report on outcome measures used to assess change in gaze stabilisation following intervention. This review includes any population completing gaze stabilisation exercises. Scoping review. We searched key terms in the following databases: PubMed, CINAHL, Scopus and Cochrane. Two researchers reviewed titles, abstracts and full-text articles for inclusion. Data retrieved included: patient diagnosis, specific interventions provided, dose and dosage of gaze stabilisation interventions and outcome measures. From the initial 1609 results, 138 studies were included. Data extraction revealed that only 13 studies (9.4%) reported all parameters of dose and dosage. Most studies used other interventions in addition to gaze stabilisation exercises. Half of the studies did not use a clinical or instrumented outcome measure of gaze stability, using only patient-reported outcome measures. Clinical tests of gaze stability were used in 21.1% of studies, and instrumented measures of gaze stability were used in 14.7% of studies. Full reporting of the dose and dosage of gaze stabilisation interventions is infrequent, impairing the ability to translate current evidence into clinical care. Most studies did not use a clinical or instrumented measure of gaze stabilisation as outcome measures, questioning the validity of intervention effects. Improved reporting and use of outcome measures are necessary to establish optimal intervention parameters for those with gaze stability impairments.
Location: United States of America
Start Date: 2022
End Date: 2024
Funder: National Institute on Aging
View Funded Activity