RESUMEN
BACKGROUND: Mild traumatic brain injury (MTBI) is a significant public health problem affecting approximately 1 million people annually in the USA. A total of 10-15% of individuals are estimated to have persistent post-traumatic symptoms. This study aimed to determine whether focused, scheduled telephone counselling during the first 3 months after MTBI decreases symptoms and improves functioning at 6 months. METHODS: This was a two-group, parallel, randomised clinical trial with the outcome assessed by blinded examiner at 6 months after injury. 366 of 389 eligible subjects aged 16 years or older with MTBI were enrolled in the emergency department, with an 85% follow-up completion rate. Five telephone calls were completed, individualised for patient concerns and scripted to address education, reassurance and reactivation. Two composites were analysed, one relating to post-traumatic symptoms that developed or worsened after injury and their impact on functioning, the other related to general health status. RESULTS: The telephone counselling group had a significantly better outcome for symptoms (6.6 difference in adjusted mean symptom score, 95% confidence interval (CI) 1.2 to 12.0), but no difference in general health outcome (1.5 difference in adjusted mean functional score, 95% CI 2.2 to 5.2). A smaller proportion of the treatment group had each individual symptom (except anxiety) at assessment. Similarly, fewer of the treatment group had daily functioning negatively impacted by symptoms with the largest differences in work, leisure activities, memory and concentration and financial independence. CONCLUSIONS: Telephone counselling, focusing on symptom management, was successful in reducing chronic symptoms after MTBI. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov, #NCT00483444.
Asunto(s)
Lesiones Encefálicas/psicología , Consejo , Líneas Directas , Trastornos por Estrés Postraumático , Adulto , Lesiones Encefálicas/diagnóstico por imagen , Demografía , Femenino , Escala de Coma de Glasgow , Humanos , Masculino , Índice de Severidad de la Enfermedad , Trastornos por Estrés Postraumático/etiología , Trastornos por Estrés Postraumático/prevención & control , Trastornos por Estrés Postraumático/psicología , Tomografía Computarizada por Rayos XRESUMEN
OBJECTIVE: This study examined psychiatric sequelae of traumatic brain injuries in outpatients and their relation to functional disability. METHOD: Fifty consecutive outpatients with traumatic brain injuries who came to a brain injury rehabilitation clinic for initial evaluation were examined for DSM-III-R diagnoses with the use of the National Institute of Mental Health Diagnostic Interview Schedule. The patients completed the Medical Outcomes Study Health Survey to assess functional disability and a questionnaire to assess postconcussion symptoms and self-perceptions of the severity of their brain injuries and cognitive functioning. RESULTS: Thirteen (26%) of the patients had current major depression, and an additional 14 (28%) reported a first-onset major depressive episode after the injury that had resolved. Twelve (24%) had current generalized anxiety disorder, and four (8%) reported current substance abuse. The group with depression and/or anxiety was significantly more impaired than the nondepressed/nonanxious patients according to the Medical Outcomes Study Health Survey measures of emotional role functioning, mental health, and general health perceptions. The depressed/anxious group also rated their injuries as significantly more severe and their cognitive functioning as significantly worse, despite the lack of significant differences in objective measures of severity of injury and Mini-Mental State examination scores. The depressed patients reported significantly more postconcussion symptoms that were increasing in severity over time. CONCLUSIONS: Depression and anxiety are common in outpatients with traumatic brain injuries. Patients with depression or anxiety are more functionally disabled and perceive their injury and cognitive impairment as more severe. Depressed patients report more increasingly severe postconcussion symptoms.
Asunto(s)
Atención Ambulatoria , Lesiones Encefálicas/rehabilitación , Trastornos Mentales/diagnóstico , Adulto , Trastornos de Ansiedad/diagnóstico , Trastornos de Ansiedad/epidemiología , Trastornos de Ansiedad/etiología , Conmoción Encefálica/complicaciones , Conmoción Encefálica/diagnóstico , Lesiones Encefálicas/complicaciones , Comorbilidad , Trastorno Depresivo/diagnóstico , Trastorno Depresivo/epidemiología , Trastorno Depresivo/etiología , Evaluación de la Discapacidad , Femenino , Humanos , Masculino , Trastornos Mentales/epidemiología , Trastornos Mentales/etiología , Prevalencia , Escalas de Valoración Psiquiátrica , Índice de Severidad de la EnfermedadRESUMEN
Our goal is to show how muscle properties can be used to understand the exercise performance limitations of the elderly. We show that magnetic resonance (MR) imaging and spectroscopy are useful for noninvasively characterizing the structural and energetic properties of muscle in vivo. Determination of muscle volume and cross-sectional area is easily and rapidly accomplished by applying quantitative morphometric methods to MR images. New MR spectroscopic techniques provide a noninvasive "biopsy" of the oxidative, glycolytic, and contractile capacities of muscle fibers. We show how the structural and energetic properties measured by MR can be used to define the functional capacity of muscle and the contribution of this capacity to the performance of the whole body (e.g., VO2max). Finally, we relate these laboratory measures of muscle properties and performance to activities meaningful to the functioning of the elderly in everyday life, such as sustained walking and stair climbing.
Asunto(s)
Envejecimiento/patología , Envejecimiento/fisiología , Imagen por Resonancia Magnética , Músculo Esquelético/anatomía & histología , Músculo Esquelético/fisiología , Actividades Cotidianas , Anciano , Envejecimiento/metabolismo , Metabolismo Energético , Ejercicio Físico/fisiología , Humanos , Espectroscopía de Resonancia Magnética , Contracción Muscular , Fibras Musculares de Contracción Rápida/ultraestructura , Fibras Musculares de Contracción Lenta/ultraestructura , Músculo Esquelético/metabolismo , Consumo de OxígenoRESUMEN
BACKGROUND: The study addressed whether changes in gait speed in community-dwelling older adults were associated with changes in fitness (strength and aerobic capacity), physical health status, and/or depressive symptoms. METHODS: The study sample comprised 152 community-dwelling adults aged 68-85 who had participated in an exercise study. Study measures at baseline and 6-month follow-up included gait speed, a leg strength score, maximal aerobic capacity (VO2max), CES-Depression scale, and physical health status (SIP Physical Dimension). RESULTS: In cross-sectional regression analyses, leg strength, VO2max, weight, and the strength by VO2max interaction term were significant independent predictors of gait speed (R2 = 26%). Based upon the observed 7% increase in VO2max and 8% increase in strength in the exercise groups, the regression model predicted only a 2% (1.5 m/min) increase in gait speed, which did not differ significantly from the observed increase of 0% (.32 m/min). The strongest correlate of change in gait speed was change in CES-D scores (partial R = -.37). Change in physical health status also correlated with change in gait speed (partial R = -.28), while change in fitness did not. CONCLUSIONS: The results suggest, in the range of fitness of the study sample, that changes in gait speed are related to changes in depressive symptoms and physical health status, but not to modest changes in fitness. A model assuming nonlinear relationships may be appropriate for understanding how strength and aerobic capacity affect gait speed.
Asunto(s)
Envejecimiento/psicología , Marcha , Anciano , Anciano de 80 o más Años , Depresión/psicología , Femenino , Estado de Salud , Humanos , Masculino , Análisis de RegresiónRESUMEN
BACKGROUND: The study tested the effect of strength and endurance training on gait, balance, physical health status, fall risk, and health services use in older adults. METHODS: The study was a single-blinded, randomized controlled trial with intention-to-treat analysis. Adults (n = 105) age 68-85 with at least mild deficits in strength and balance were selected from a random sample of enrollees in a health maintenance organization. The intervention was supervised exercise (1-h sessions, three per week, for 24-26 weeks), followed by self-supervised exercise. Exercise groups included strength training using weight machines (n = 25), endurance training using bicycles (n = 25), and strength and endurance training (n = 25). Study outcomes included gait tests, balance tests, physical health status measures, self-reported falls (up to 25 months of follow-up), and inpatient and outpatient use and costs. RESULTS: There were no effects of exercise on gait, balance, or physical health status. Exercise had a protective effect on risk of falling (relative hazard = .53, 95% CI = .30-.91). Between 7 and 18 months after randomization, control subjects had more outpatient clinic visits (p < .06) and were more likely to sustain hospital costs over $5000 (p < .05). CONCLUSIONS: Exercise may have beneficial effects on fall rates and health care use in some subgroups of older adults. In community-living adults with mainly mild impairments in gait, balance, and physical health status, short-term exercise may not have a restorative effect on these impairments.
Asunto(s)
Accidentes por Caídas , Marcha , Servicios de Salud/estadística & datos numéricos , Educación y Entrenamiento Físico , Resistencia Física , Equilibrio Postural , Aerobiosis , Anciano , Envejecimiento/fisiología , Medicina Comunitaria/métodos , Ejercicio Físico , Femenino , Costos de la Atención en Salud , Estado de Salud , Humanos , Masculino , Factores de RiesgoRESUMEN
BACKGROUND: Age-related loss in physiologic capacities contributes to the decline in physical function in the elderly population. Despite the beneficial effects of exercise interventions on maximal physiologic capacity measures, the functional benefits have not been shown in independently living older adults. The objective of this study was to evaluate exercise in independent older adults for significant and meaningful improvements in physical function, not detected by commonly used measures of physical function. METHODS: In a randomized controlled study, 49 independently living men and women were assigned to either a nonexercise control group (Control; n = 26) or an exercise training group (Exercise; n = 23). Participants (age = 76+/-4) in good general health were recruited from retirement communities or apartments. The combined endurance and strength training was performed at 75% to 80% intensity; the groups met 3 times/week for 6 months of supervised sessions. Outcome measures included physical capacity, health status, and physical function using a newly developed performance test--the Continuous Scale-Physical Functional Performance test (CS-PFP). RESULTS: Compared to the Control group, the Exercise group showed significant increases in maximal oxygen consumption (11%) and muscle strength (33%). No significant differences were found between groups for changes in the Sickness Impact Profile, SF-36 scales, or the 6-minute walk. However, the CS-PFP score improved significantly in the Exercise group (14%, effect size 0.80). CONCLUSIONS: Independent older adults gain meaningful functional benefits from several months of exercise training. The public health importance of physical activity may relate not just to its role in preventing decline, but also to its role in enhancing physical function.
Asunto(s)
Actividades Cotidianas , Envejecimiento/fisiología , Ejercicio Físico/fisiología , Anciano , Tolerancia al Ejercicio/fisiología , Femenino , Estado de Salud , Humanos , Contracción Isométrica/fisiología , Masculino , Evaluación de Resultado en la Atención de Salud , Consumo de Oxígeno/fisiología , Resistencia Física/fisiología , Equilibrio Postural/fisiología , Perfil de Impacto de Enfermedad , Caminata/fisiología , Levantamiento de Peso/fisiologíaRESUMEN
This study determined the cellular energetic and structural adaptations of elderly muscle to exercise training. Forty male and female subjects (69.2 +/- 0.6 yr) were assigned to a control group or 6 mo of endurance (ET) or resistance training (RT). We used magnetic resonance spectroscopy and imaging to characterize energetic properties and size of the quadriceps femoris muscle. The phosphocreatine and pH changes during exercise yielded the muscle oxidative properties, glycolytic ATP synthesis, and contractile ATP demand. Muscle biopsies taken from the same site as the magnetic resonance measurements were used to determine myosin heavy chain isoforms, metabolite concentrations, and mitochondrial volume densities. The ET group showed changes in all energetic pathways: oxidative capacity (+31%), contractile ATP demand (-21%), and glycolytic ATP supply (-56%). The RT group had a large increase in oxidative capacity (57%). Only the RT group exhibited change in structural properties: a rise in mitochondrial volume density (31%) and muscle size (10%). These results demonstrate large energetic, but smaller structural, adaptations by elderly muscle with exercise training. The rise in oxidative properties with both ET and RT suggests that the aerobic pathway is particularly sensitive to exercise training in elderly muscle. Thus elderly muscle remains adaptable to chronic exercise, with large energetic changes accompanying both ET and RT.
Asunto(s)
Anciano/fisiología , Metabolismo Energético , Ejercicio Físico/fisiología , Músculo Esquelético/fisiología , Resistencia Física , Adenosina Trifosfato/metabolismo , Femenino , Glucólisis , Humanos , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Masculino , Contracción Muscular , Desarrollo de Músculos , Músculo Esquelético/crecimiento & desarrollo , Músculo Esquelético/metabolismo , Fosforilación Oxidativa , Valores de ReferenciaRESUMEN
Impairment rating is regularly reported for trauma and other conditions but rarely for burns. The purposes of this study were: (1) to report impairment collected prospectively at our burn center, (2) to relate this impairment to measures of psychosocial and functional outcome, and (3) to compare these data to similar data from another burn center to verify that rating impairment is standardized and that the impairments are similar. We studied 139 patients from the University of Washington (UW) Burn Center and 100 patients from the University of Texas (UT) Southwestern Burn Center. The average whole person impairment (WPI) ratings at the University of Washington were 17% and this correlated with total body surface area burned and days off work. It did not correlate with Brief Symptom Inventory (BSI), Functional Independence Measure (FIM), Short-Form 36-Item Health Survey (SF-36), Satisfaction With Life Scale (SWLS), and the Community Integration Questionnaire (CIQ). Average whole person impairment ratings at UT Southwestern were similar at 19%. Several components of the impairment rating, however, differed at the two institutions. To minimize this variation, we recommend: (1) use the skin impairment definitions of the fifth edition of the Guides to the Evaluation of Permanent Impairment (or the most recent published versions of the Guide), and (2) include sensory impairment in healed burns and skin grafts in the skin impairment.
Asunto(s)
Quemaduras/rehabilitación , Evaluación de la Discapacidad , Adulto , Amputación Quirúrgica , Quemaduras/patología , Quemaduras/psicología , Femenino , Indicadores de Salud , Humanos , Masculino , Persona de Mediana Edad , Satisfacción Personal , Pronóstico , Estudios Prospectivos , Escalas de Valoración Psiquiátrica , Psicometría , Calidad de VidaRESUMEN
Despite improvements in surgical repair of pressure sores, recurrence rates greater than 80 percent are reported, thus indicating that this difficult problem is not yet solved. Recurrence results in additional hospitalizations and increased medical expenses. Because associated general clinical and social issues are numerous for these patients, our physical medicine and rehabilitation colleagues are active participants in their perioperative medical care. In addition, the Department of Physical Medicine and Rehabilitation also directs a complete postreconstruction rehabilitation and education program for them. The results of surgically repaired pressure sores for patients managed in this collaborative fashion have not been previously reported. Pressure sore patients at the Harborview and University of Washington Medical Centers are evaluated by plastic surgery colleagues together with the Department of Physical Medicine and Rehabilitation. Patients believed to be candidates for complete postoperative rehabilitation are offered surgical repair and constitute this study cohort. Individuals who cannot cooperate with our protocol are treated nonoperatively and are not included in this study. A retrospective analysis of all 158 patients (mean age 34.5 years) operated on for 268 grade III and IV pressure sores between October of 1977 and December of 1989 was performed. Following surgical debridement and reconstruction, patients receive their principal medical care from the Department of Physical Medicine and Rehabilitation service while the Plastic Surgery Department manages the surgical wounds. Graduated patient mobilization is initiated in accord with a mutually agreed upon standardized protocol. New or primary sores numbered 174 (65 percent), and recurrent or secondary sores numbered 94 (35 percent). Mean patient follow-up was 3.7 years. The overall pressure sore recurrence rate (recurrence at the same site) was 19 percent, and the overall patient recurrence rate (previous patient developing a new sore) was 25 percent. Recurrence rates of 22 and 15 percent were noted for primary and secondary pressure sores, respectively. On most recent examination, 131 patients (83 percent) had intact pelvic and perineal skin. These results support a collaborative approach to the management of high-grade pressure sore patients. Our protocol of mutual patient evaluation followed by surgical reconstruction and postoperative rehabilitation yields notably low recurrence rates of both primary and secondary sores. In addition, the high percentage of patients who manifest long-term maintenance of skin integrity demonstrates the excellent education in personal skin and self-care that this approach provides. Not only do patients enjoy successful and durable reconstructive results, but additional hospitalizations and health care expenses implicit to pressure sore recurrence are consequently diminished. This collaborative clinical effort remains our standard of care.
Asunto(s)
Desbridamiento/rehabilitación , Grupo de Atención al Paciente , Modalidades de Fisioterapia , Complicaciones Posoperatorias/rehabilitación , Úlcera por Presión/cirugía , Adulto , Terapia Combinada , Femenino , Estudios de Seguimiento , Hospitales Universitarios , Humanos , Masculino , Cuidados Posoperatorios , Úlcera por Presión/etiología , Recurrencia , Reoperación , Estudios Retrospectivos , WashingtónRESUMEN
The literature on time off work and return to work after burns is incomplete. This study addresses this and includes a systematic literature review and two-center series. The literature was searched from 1966 through October 2000. Two-center data were collected on 363 adults employed outside of the home at injury. Data on employment, general demographics, and burn demographics were collected. The literature search found only 10 manuscripts with objective data, with a mean time off work of 10 weeks and %TBSA as the most important predictor of time off work. The mean time off work for those who returned to work by 24 months was 17 weeks and correlated with %TBSA. The probability of returning to work was reduced by a psychiatric history and extremity burns and was inversely related to %TBSA. In the two-center study, 66% and 90% of survivors had returned to work at 6 and 24 months post-burn. However, in the University of Washington subset of the data, only 37% had returned to the same job with the same employer without accommodations at 24 months, indicating that job disruption is considerable. The impact of burns on work is significant.
Asunto(s)
Absentismo , Quemaduras/complicaciones , Empleo , Adulto , Quemaduras/rehabilitación , Evaluación de la Discapacidad , Femenino , Estudios de Seguimiento , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Valor Predictivo de las Pruebas , Recuperación de la Función , Factores de Tiempo , Índices de Gravedad del TraumaRESUMEN
Evaluation of community integration is a meaningful outcome criterion after major burn injury. The Community Integration Questionnaire (CIQ) was administered to 463 individuals with major burn injuries. The CIQ results in Total, Home Integration, Social Integration, and Productivity scores. The purposes of this study were to determine change in CIQ scores over time and what burn injury and demographic factors predict CIQ scores. The CIQ scores did not change significantly from 6 to 12 to 24 months postburn injury. Home integration scores were best predicted by sex and living situation; Social Integration scores by marital status; and Productivity scores by functional outcome, burn severity, age, and preburn work factors. The data demonstrate that individuals with burn injuries have significant difficulties with community integration due to burn and nonburn related factors. CIQ scores did not improve over time but improvement may have occurred before the initial 6-month postburn injury follow-up in this study.
Asunto(s)
Quemaduras/rehabilitación , Adulto , Eficiencia , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Valor Predictivo de las Pruebas , Análisis de Regresión , Distribución por Sexo , Factores Socioeconómicos , Encuestas y Cuestionarios , Comunidad Terapéutica , Factores de TiempoRESUMEN
INTRODUCTION: Burns create a myriad of complications that affect the child's developmental, functional and aesthetic status. The WeeFIM is a standardized measure of functional performance developed for use in children 6-months to 8-years of age but with application through adolescence. It includes 18 domains of performance which are scored on a 7-point scale from 'total assistance' to 'complete independence'. In this study, the WeeFIM was used to evaluate the influence of burn size on functional independence and on time to recovery. METHODS: Children, 6 months to 16 years of age, with total body surface area (TBSA) bums of 10-100% burn injury were recruited for a 2-year longitudinal study. Due to unstable WeeFIM measurements on children 6 months to 6 years, analyses on normalized WeeFIM scores among subjects 6-16 years are presented. Children were evaluated at discharge from acute care, 6 months, 1 year and 2 years after burn injury. FINDINGS: In this analysis, 454 WeeFIM evaluations from 249 patients, 6-16 years of age, were reviewed. While mean WeeFIM scores varied significantly at discharge based on the size of burn, there were no significant differences in any of the WeeFIM scales at 24 months post-burn. At 24 months, the mean WeeFIM score for all children, independent of size of their bum, indicated full independence. Hands-on assistance was not required for performing activities of daily living (ADLs). The rates of improvement differed statistically by size of bum. Maximum improvement was attained by 6 months for 10-15% TBSA burns, 12 months for 16-30% burns, 12 months for 31-50% burns and 24 months for 51-100% TBSA. CONCLUSION: The WeeFIM can be utilized by burn centres to describe diminished functional capacity at discharge from acute care for severely burnt children. The tool can be used to track return to baseline independence after a major burn injury in a paediatric population.
Asunto(s)
Quemaduras/complicaciones , Evaluación de la Discapacidad , Actividades Cotidianas , Adolescente , Distribución de Chi-Cuadrado , Niño , Preescolar , Niños con Discapacidad/rehabilitación , Femenino , Humanos , Lactante , Puntaje de Gravedad del Traumatismo , Masculino , Valor Predictivo de las Pruebas , Calidad de VidaRESUMEN
Mild traumatic brain injury (TBI) is a very common injury, resulting in immediate and possible long-term symptoms. The accurate and consistent definition of mild TBI is important in the initial and rehabilitation management of the injury, and in research concerning mild TBI. A definition of mild TBI has been developed by the Head Injury Interdisciplinary Special Interest Group of the American Congress of Rehabilitation Medicine. Within the spectrum of injury severity in mild TBI there are several classification systems, primarily used in management of acute mild TBI, that breakdown mild TBI into grades of injury severity. These are based upon the presence or absence of mental status changes, amnesia, loss of consciousness, anatomical lesion or neurological deficit.
Asunto(s)
Daño Encefálico Crónico/clasificación , Traumatismos Cerrados de la Cabeza/clasificación , Traumatismos en Atletas/clasificación , Traumatismos en Atletas/diagnóstico , Traumatismos en Atletas/rehabilitación , Conmoción Encefálica/clasificación , Conmoción Encefálica/diagnóstico , Conmoción Encefálica/rehabilitación , Daño Encefálico Crónico/diagnóstico , Daño Encefálico Crónico/rehabilitación , Mapeo Encefálico , Escala de Coma de Glasgow , Traumatismos Cerrados de la Cabeza/diagnóstico , Traumatismos Cerrados de la Cabeza/rehabilitación , Humanos , Examen Neurológico , Grupo de Atención al PacienteRESUMEN
Traumatic brain injury has been associated with many physical and neurobehavioral consequences, including pain problems. Documented most has been the presence of posttraumatic headaches that are associated with the postconcussion syndrome. This study therefore examined types and rates of chronic pain problems in patients seen in an outpatient brain injury rehabilitation program. A total of 104 patients were evaluated, 66 of whom were male and 38 female, and the average time postinjury was 26 months. Headaches were the most frequent chronic pain problem across both mild and the moderate/severe groups, although in the former, a significantly higher frequency was noted (89%) when compared against the latter group. The same relative rates were seen for chronic neck/shoulder, back, and other pain problems. The mild group also showed a higher frequency of concurrent pain problems, whereas in the moderate/severe group only one patient had more than one chronic pain problem. Results also showed that in the mild group neck/shoulder accompanied headaches 47% of the time, and back pain coexisted with headaches 44% of the time. These results underscore the high frequency of chronic pain problems in the mild head injury population and implicate the need for avoiding the mislabeling of symptoms such attentional deficits or psychological distress as attributable only to head injury sequelae in those with coexisting chronic pain. Early identification and intervention of pain syndromes in the mild head-injury population is also suggested.
Asunto(s)
Lesiones Encefálicas/fisiopatología , Dolor , Adolescente , Adulto , Dolor de Espalda/diagnóstico , Lesiones Encefálicas/rehabilitación , Enfermedad Crónica , Traumatismos Craneocerebrales/clasificación , Femenino , Cefalea/diagnóstico , Humanos , Puntaje de Gravedad del Traumatismo , Masculino , Persona de Mediana Edad , Dolor/diagnóstico , Dolor Intratable/diagnóstico , Estudios RetrospectivosRESUMEN
This study determined the decline in oxidative capacity per volume of human vastus lateralis muscle between nine adult (mean age 38.8 years) and 40 elderly (mean age 68.8 years) human subjects (age range 25-80 years). We based our oxidative capacity estimates on the kinetics of changes in creatine phosphate content ([PCr]) during recovery from exercise as measured by (31)P magnetic resonance (MR) spectroscopy. A matched muscle biopsy sample permitted determination of mitochondrial volume density and the contribution of the loss of mitochondrial content to the decline in oxidative capacity with age. The maximal oxidative phosphorylation rate or oxidative capacity was estimated from the PCr recovery rate constant (k(PCr)) and the [PCr] in accordance with a simple electrical circuit model of mitochondrial respiratory control. Oxidative capacity was 50 % lower in the elderly vs. the adult group (0.61 +/- 0.04 vs. 1.16 +/- 0.147 mM ATP s(-1)). Mitochondrial volume density was significantly lower in elderly compared with adult muscle (2.9 +/- 0.15 vs. 3.6 +/- 0.11 %). In addition, the oxidative capacity per mitochondrial volume (0.22 +/- 0.042 vs. 0.32 +/- 0.015 mM ATP (s %)(-1)) was reduced in elderly vs. adult subjects. This study showed that elderly subjects had nearly 50 % lower oxidative capacity per volume of muscle than adult subjects. The cellular basis of this drop was a reduction in mitochondrial content, as well as a lower oxidative capacity of the mitochondria with age.
Asunto(s)
Envejecimiento/fisiología , Músculo Esquelético/metabolismo , Consumo de Oxígeno/fisiología , Adenosina Difosfato/metabolismo , Adenosina Trifosfato/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Cromatografía Líquida de Alta Presión , Estimulación Eléctrica , Femenino , Humanos , Espectroscopía de Resonancia Magnética , Masculino , Persona de Mediana Edad , Mitocondrias Musculares/metabolismo , Mitocondrias Musculares/ultraestructura , Músculo Esquelético/química , Fosforilación Oxidativa , Fosfocreatina/metabolismo , Isótopos de Fósforo/análisisRESUMEN
The resolution of a muscular hematoma is an important step in the recovery from a muscle injury. Because heat application has been advocated to accelerate this resolution, the effectiveness of microwave diathermy as a means of selectively heating the musculature was studied. For this purpose muscular hematomas were formed in 6 pigs by bilateral injections of blood labeled with the radioisotope chromium-51 (Cr51) into the biceps femoris muscle. One hematoma site was heated with microwave diathermy and the opposite side served as a control. The tissue temperature at the hematoma site was shown to be in the therapeutic range of 42 to 45C, which would cause a maximal local blood flow response. A decay curve was formed by counting the radioactivity of the hematoma site with a scintillation counter. Best fit lines fitted to the decay curves to determine effective half-life values showed that the treated side had a significantly shorter washout time than the control side. This result supports the use of heat as an adjunct to other therapy aimed at resolution of muscular hematomas.
Asunto(s)
Diatermia , Hematoma/terapia , Microondas/uso terapéutico , Enfermedades Musculares/terapia , Animales , PorcinosRESUMEN
Humans produce less muscle force (F) as they age. However, the relationship between decreased force and muscle cross-sectional area (CSA) in older humans is not well documented. We examined changes in F and CSA to determine the relative contributions of muscle atrophy and specific force (F/CSA) to declining force production in aging humans. The proportions of myosin heavy chain (MHC) isoforms were characterized to assess whether this was related to changes in specific force with age. We measured the peak force of isokinetic knee extension in 57 males and females aged 23-80 years, and used magnetic resonance imaging to determine the contractile area of the quadriceps muscle. Analysis of MHC isoforms taken from biopsies of the vastus lateralis muscle showed no relation to specific force. F, CSA, and F/CSA decreased with age. Smaller CSA accounted for only about half of the 39% drop in force that occurred between ages 65-80 years. Specific force dropped about 1.5% per year in this age range, for a total decrease of 21%. Thus, quantitative changes in muscle (atrophy) are not sufficient to explain the strength loss associated with aging.
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Envejecimiento/patología , Envejecimiento/fisiología , Contracción Muscular/fisiología , Músculo Esquelético/anatomía & histología , Músculo Esquelético/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Articulación de la Rodilla , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Fibras Musculares Esqueléticas/fisiología , Fibras Musculares Esqueléticas/ultraestructura , Atrofia Muscular/patología , Atrofia Muscular/fisiopatología , Cadenas Pesadas de Miosina/metabolismoRESUMEN
We report 3 cases of isolated deep peroneal nerve injury as a complication of arthroscopic knee surgery. At the level of the knee joint, the deep and superficial peroneal nerves are usually joined as the common peroneal nerve. However, because of the fascicular structure, a partial nerve injury can result in an isolated injury to the deep peroneal nerve fibers. Due to the intraneural topography of the peroneal nerve, electrodiagnostic studies in a partial nerve injury may erroneously indicate a more distal lesion.
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Articulación de la Rodilla/cirugía , Nervio Peroneo/lesiones , Potenciales de Acción/fisiología , Adulto , Artroscopía , Electromiografía , Femenino , Humanos , Masculino , Meniscos Tibiales/cirugía , Persona de Mediana Edad , Neuronas Motoras/fisiología , Conducción Nerviosa/fisiología , Neuroma/etiología , Parálisis/etiología , Parálisis/fisiopatología , Neoplasias del Sistema Nervioso Periférico/etiología , Nervio Peroneo/fisiopatología , Complicaciones Posoperatorias , Lesiones de Menisco TibialRESUMEN
To be a deep-heating modality, shortwave diathermy applicators have to heat the musculature more than the subcutaneous fat. In this study, commercially available and prototype shortwave diathermy applicators were tested using tissue substitute models which allow rapid thermographic scanning of the initial linear transient temperature rise in the subcutaneous fat and muscle. The specific absorption rates (SAR) of the electromagnetic radiation were calculated throughout the tissues. Great differences were found in the deep-heating capability of these applicators. Some of the applicators heated the subcutaneous fat more than the muscle, while others were more efficient in heating the musculature.
Asunto(s)
Diatermia/instrumentación , Terapia por Ondas Cortas/instrumentación , Tejido Adiposo , Estudios de Evaluación como Asunto , Humanos , Modelos Biológicos , MúsculosRESUMEN
Plastic ankle-foot orthoses (PAFOs) are worn by persons with hemiplegia to correct gait abnormalities such as foot drop during swing and insufficient pushoff during stance. A PAFO should resist plantarflexion sufficiently to provide toe clearance during the swing phase of gait without excessively increasing the knee bending moment during heelstrike. It should resist dorsiflexion during late stance to raise the heel to simulate gastrocnemiussoleus muscle group function. Five PAFOs were evaluated as to the amount of plantarflexion-dorsiflexion resistance that was provided when worn by hemiplegic and able-bodied subjects. A self-aligning goniometer measured ankle angle as the subject walked, and a gait event marker system recorded occurrences of gait events. The Seattle design polypropylene orthosis which enclosed the malleoli was the least flexible; it provided the greatest plantarflexion resistance to ensure against toe drag during swing for patients with severe plantarflexion spasticity. It offered the greatest dorsiflexion resistance to provide a good substitute for the gastrocnemiussoleus during the latter part of stance as required by patients with flaccid plantarflexors and full ankle range of motion. Progressive trimming of the Seattle design polypropylene orthosis made it more flexible and comparable in function to the commercially available Engen and Teufel orthoses. The latter 2 orthoses did not provide a pushoff substitute as well as the Seattle design orthosis which enclosed the malleoli, but they did provide an adequate amount of toe clearance during swing. The more flexible orthoses would be appropriate for subjects with mild to moderate plantarflexor spasticity.