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1.
J Comput Assist Tomogr ; 46(2): 212-218, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35297577

RESUMEN

BACKGROUND: Volumetric measures of intrinsic foot muscle and intermuscular adipose tissue (IMAT) infiltration are important in understanding foot injury and disease. We questioned whether measures of muscle and fat derived from computed tomography (CT) and magnetic resonance (MR) would be comparable. METHODS: This study determined the correlation and level of agreement between CT and MR measurements of foot muscle and IMAT from 32 subjects with diabetes and peripheral neuropathy. Volumetric CT and DIXON 3T MR scans were obtained. Intermuscular adipose tissue and muscle volumes used to create the IMAT to muscle ratio were obtained by segmenting the forefoot muscle compartment from each modality. RESULTS: Computed tomography IMAT ratios were significantly correlated (r = 0.85, P < 0.0001) with MR IMAT ratios. Computed tomography and MR IMAT ratio mean difference between CT and MR was small (0.044 unit, Bland-Altman plots). CONCLUSIONS: The CT and MR IMAT ratio measurements were highly correlated, indicating both modalities represent tissue quantification similarly.Level of Evidence: 2Technical Efficacy: 1.


Asunto(s)
Tejido Adiposo , Imagen por Resonancia Magnética , Tejido Adiposo/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética/métodos , Espectroscopía de Resonancia Magnética , Músculo Esquelético/diagnóstico por imagen , Tomografía Computarizada por Rayos X
2.
Diabetes Metab Res Rev ; 36 Suppl 1: e3259, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31851432

RESUMEN

Clinicians and patients face a dilemma in understanding how best to resume walking after a healed diabetic neuropathic ulcer. The objectives of this brief review are to: provide context for the patient's health and mobility status; propose 5 suggestions to safely and effectively progress mobility following a healed foot ulcer; and to consider topics for future research to improve care in this area. Rates of ulcer recurrence and mortality are high, and activity is low following a diabetic foot wound. Medical and rehabilitation approaches have emphasized protection of the insensitive, fragile foot with the hope to prevent subsequent harm to the foot and person. In particular, the 1-2 months following wound unloading and "healing" have the greatest risk for ulcer recurrence. While early protection should be emphasized, a growing body of evidence suggests that over-protection of the foot and limited walking can be harmful, presumably because of the negative effects of prolonged immobility and stress protection. Multiple recent studies report the ability of exercise and walking to have a positive effect on various diabetic foot outcomes without additional harm. Much less is known about how an ulcerated foot can resume walking after the wound is healed. This review integrates available guidelines, evidence, and precautions to suggest advice on how best to resume and progress walking in this population at high risk for ulcer recurrence.


Asunto(s)
Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 2/complicaciones , Pie Diabético/prevención & control , Pie Diabético/rehabilitación , Ejercicio Físico , Cooperación del Paciente , Cicatrización de Heridas , Pie Diabético/etiología , Manejo de la Enfermedad , Humanos
3.
J Sport Rehabil ; 30(4): 638-645, 2020 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-33291065

RESUMEN

CONTEXT: The authors hypothesized that in people with hip-related groin pain, less static ankle dorsiflexion could lead to compensatory hip adduction and contralateral pelvic drop during step-down. Ankle dorsiflexion may be a modifiable factor to improve ability in those with hip-related groin pain to decrease hip/pelvic motion during functional tasks and improve function. OBJECTIVE: To determine whether smaller static ankle dorsiflexion angles were associated with altered ankle, hip, and pelvis kinematics during step-down in people with hip-related groin pain. DESIGN: Cross-sectional Setting: Academic medical center. PATIENTS: A total of 30 people with hip-related groin pain (12 males and 18 females; 28.7 [5.3] y) participated. INTERVENTION: None. MAIN OUTCOME MEASURES: Weight-bearing static ankle dorsiflexion with knee flexed and knee extended were measured via digital inclinometer. Pelvis, hip, and ankle kinematics during forward step-down were measured via 3D motion capture. Static ankle dorsiflexion and kinematics were compared with bivariate correlations. RESULTS: Smaller static ankle dorsiflexion angles were associated with smaller ankle dorsiflexion angles during the step-down for both the knee flexed and knee extended static measures. Among the total sample, smaller static ankle dorsiflexion angle with knee flexed was associated with greater anterior pelvic tilt and greater contralateral pelvic drop during the step-down. Among only those who did not require a lowered step for safety, smaller static ankle dorsiflexion angles with knee flexed and knee extended were associated with greater anterior pelvic tilt, greater contralateral pelvic drop, and greater hip flexion. CONCLUSIONS: Among those with hip-related groin pain, smaller static ankle dorsiflexion angles are associated with less ankle dorsiflexion motion and altered pelvis and hip kinematics during a step-down. Future research is needed to assess the effect of treating restricted ankle dorsiflexion on quality of motion and symptoms in patients with hip-related groin pain.


Asunto(s)
Articulación del Tobillo/fisiopatología , Artralgia/fisiopatología , Fenómenos Biomecánicos/fisiología , Articulación de la Cadera/fisiopatología , Subida de Escaleras/fisiología , Adolescente , Adulto , Artralgia/etiología , Estatura , Estudios Transversales , Femenino , Ingle , Humanos , Masculino , Limitación de la Movilidad , Movimiento/fisiología , Pelvis , Rango del Movimiento Articular/fisiología , Soporte de Peso/fisiología , Adulto Joven
4.
J Magn Reson Imaging ; 49(5): 1285-1295, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30230096

RESUMEN

BACKGROUND: Diffusion tensor imaging (DTI) has been used to characterize calf skeletal muscle architecture. PURPOSE: To assess the diffusional properties of the calf muscles of subjects with and without diabetes, at rest and during isometric plantarflexion exercise. STUDY TYPE: Prospective. SUBJECTS: Twenty-six subjects in two groups: 13 healthy and 13 subjects with type 2 diabetes (DM); each group consisted of seven females and six males. FIELD STRENGTH/SEQUENCE: 3T/2D single-shot spin echo planar imaging. ASSESSMENT: Fractional anisotropy (FA), mean diffusivity (MD), diffusion eigenvalues, and fiber tracking indices were obtained from the medial gastrocnemius (MG), lateral gastrocnemius (LG), and soleus (SOL) muscles of the calf at rest and during isometric plantarflexion exercise. STATISTICAL TESTS: We used a combination of nonparametric (Wilcoxon) and parametric (t-test) statistical assessments. RESULTS: The medial gastrocnemius muscle had more indices with significant differences between the two groups (six indices with P < 0.05) than did the lateral gastrocnemius (three indices with P < 0.05) and soleus muscles (only one index with P < 0.05). While the healthy group showed elevated MD values from rest to exercise (MG = 5.83%, LG = 13.45%, and SOL = 11.68%), the diabetic MD showed higher increases (MG = 19.74%, LG = 29.31%, and SOL = 20.84%) that were different between groups (MG: P = 0.009, LG: P = 0.037, and SOL: P = 0.049). DATA CONCLUSION: Our results indicate considerable diffusional changes between healthy subjects and subjects with diabetes at rest and during isometric plantarflexion exercise in the calf muscles. The medial gastrocnemius muscle displayed the most diffusion sensitivity to diabetes-related microstructural changes. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:1285-1295.


Asunto(s)
Diabetes Mellitus Tipo 2 , Imagen de Difusión Tensora/métodos , Pierna/diagnóstico por imagen , Músculo Esquelético/diagnóstico por imagen , Adulto , Anciano , Anisotropía , Imagen Eco-Planar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Estudios Prospectivos
5.
J Magn Reson Imaging ; 50(2): 474-480, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30447040

RESUMEN

BACKGROUND: Impaired foot perfusion is a primary contributor to foot ulcer formation. There is no existing device nor method that can be used to measure local foot perfusion during standardized foot muscle exercise in an MRI environment. PURPOSE: To develop a new MRI-compatible foot dynamometer and MRI methods to characterize local perfusion in diabetic feet with ulcers. STUDY TYPE: Prospective. POPULATION/SUBJECTS: Seven participants without diabetes and 10 participants with diabetic foot ulcers. FIELD STRENGTH/SEQUENCE: 3.0T, arterial spin labeling (ASL). ASSESSMENTS: Using a new MRI-compatible foot dynamometer, all participants underwent MRI ASL perfusion assessment at rest and during a standardized toe-flexion exercise. The participants without diabetes were scanned twice to assess the reproducibility of perfusion measurements. The absolute perfusion and perfusion reserve values were compared between two groups and between regions near ulcers (peri-ulcer) and away from ulcers (away-ulcer). STATISTICAL TESTS: Bland-Altman methods for the calculation of coefficient of repeatability (CR) and two-sided and unpaired Student's t-test to compare multiple differences. RESULTS: The perfusion reserves measured had the best reproducibility (CR in medial region: 1.6, lateral region: 0.9). The foot perfusion reserve was significantly lower in the participants with diabetes compared with the participants without diabetes (1.34 ± 0.32, 95% confidence interval [CI]: 1.1, 1.58 vs. 1.76 ± 0.31, 95% CI: 1.53, 1.98, P = 0.02). Both peri-ulcer exercise perfusion (8.7 ± 3.9 ml/min/100g) and perfusion reserve (1.07 ± 0.39, 95% CI: 0.78, 1.35) were significantly lower than away-ulcer exercise perfusion (12.7 ± 3.8 ml/min/100g, P = 0.02) and perfusion reserve (1.39 ± 0.37, 95% CI: 1.11, 1.66, P = 0.03), respectively. DATA CONCLUSION: This study demonstrates intravenous contrast-free methods for local perfusion in feet with ulcers by standardized exercise-based MRI. Ischemia regions around foot ulcers can be quantitatively distinguished from normal perfused muscle regions. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;50:474-480.


Asunto(s)
Pie Diabético/diagnóstico por imagen , Prueba de Esfuerzo , Úlcera del Pie/diagnóstico por imagen , Angiografía por Resonancia Magnética/métodos , Anciano , Medios de Contraste , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Perfusión , Imagen de Perfusión/métodos , Estudios Prospectivos , Reproducibilidad de los Resultados , Marcadores de Spin
6.
Am J Occup Ther ; 71(3): 7103320010P1-7103320010P12, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28422639

RESUMEN

Approximately 53 million Americans live with a disability. For decades, the National Institutes of Health (NIH) has been conducting and supporting research to discover new ways to minimize disability and enhance the quality of life of people with disabilities. After the passage of the Americans With Disabilities Act, NIH established the National Center for Medical Rehabilitation Research, with the goal of developing and implementing a rehabilitation research agenda. Currently, 17 institutes and centers at NIH invest more than $500 million per year in rehabilitation research. Recently, the director of NIH, Francis Collins, appointed a Blue Ribbon Panel to evaluate the status of rehabilitation research across institutes and centers. As a follow-up to the work of that panel, NIH recently organized a conference, "Rehabilitation Research at NIH: Moving the Field Forward." This report is a summary of the discussions and proposals that will help guide rehabilitation research at NIH in the near future.

7.
J Magn Reson Imaging ; 44(4): 940-6, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-26970103

RESUMEN

PURPOSE: To develop a noncontrast oximetric angiosome imaging approach to assess skeletal muscle oxygenation in diabetic feet. MATERIALS AND METHODS: In four healthy and five subjects with diabetes, the feasibility of foot oximetry was examined using a 3T clinical magnetic resonance imaging (MRI) scanner. The subjects' feet were scanned at rest and during a toe-flexion isometric exercise. The oxygen extraction fraction of skeletal muscle was measured using a susceptibility-based MRI method. Our newly developed MR foot oximetric angiosome model was compared with the traditional angiosome model in the assessment of the distribution of oxygen extraction fraction. RESULTS: Using the traditional angiosome during the toe-flexion exercise, the oxygen extraction fraction in the medial foot of healthy subjects increased (4.9 ± 3%) and decreased (-2.7 ± 4.4%) in subjects with diabetes (difference = 7.6%; 95% confidence interval = -13.7 ± 1.4; P = 0.02). Using the oximetric angiosome, the percent difference in the areas of oxygen extraction fraction within the 0.7-1.0 range (expected oxygen extraction fraction during exercise) between rest and exercise was higher in healthy subjects (8 ± 4%) than in subjects with diabetes (4 ± 4%; P = 0.02). CONCLUSION: This study demonstrates the feasibility of measuring skeletal muscle oxygen extraction fraction in the foot muscle during a toe-flexion isometric exercise. Instead of assessing oxygen extraction fraction in a foot muscle region linked to a supplying artery (traditional angiosome), the foot oximetric angiosome model assesses oxygen extraction fraction by its different levels in all foot muscle regions and thus may be more appropriate for assessing local ischemia in ulcerated diabetic feet. J. Magn. Reson. Imaging 2016. J. MAGN. RESON. IMAGING 2016;44:940-946.


Asunto(s)
Pie Diabético/diagnóstico por imagen , Pie Diabético/metabolismo , Angiografía por Resonancia Magnética/métodos , Músculo Esquelético/diagnóstico por imagen , Músculo Esquelético/metabolismo , Oximetría/métodos , Oxígeno/metabolismo , Anciano , Prueba de Esfuerzo/métodos , Femenino , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Masculino , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Distribución Tisular
8.
Eur Radiol ; 25(1): 99-105, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25100334

RESUMEN

OBJECTIVE: The purpose of this study is to develop a non-contrast magnetic resonance imaging (MRI) approach to evaluate skeletal muscle perfusion in the diabetic foot based on the concept of angiosomes of the foot. METHODS: Five healthy volunteers and five participants with diabetes (HbA1c = 7.2 ± 1.8%) without a history of peripheral artery disease were examined. The non-contrast perfusion measurements were performed during a toe flexion challenge. Absolute perfusion maps were created and two regions (medial and lateral) on the maps were segmented based on angiosomes. RESULT: Regional difference in the perfusion of foot muscle was readily visualized in the MRI perfusion angiosomes during the challenge. In the participants with diabetes, the perfusion during toe flexion challenge was significantly lower than in healthy volunteers (P < 0.01). The average perfusion for the medial plantar region of the right foot was lower in subjects with diabetes (38 ± 9 ml/min/100 g) than in healthy subjects (93 ± 33 ml/min/100 g). CONCLUSIONS: Non-contrast MRI perfusion angiosome maps demonstrate the feasibility of determining regional perfusion in foot muscles during toe challenge and may facilitate evaluation of muscle perfusion in diabetic feet. KEY POINTS: • Non-contrast MRI perfusion angiosome maps measure regional perfusion in foot muscles non-invasively. • Foot perfusion response to challenge is reduced in persons with diabetes. • MRI perfusion angiosome maps may help evaluation of regional foot muscle perfusion.


Asunto(s)
Pie Diabético/patología , Pie/irrigación sanguínea , Músculo Esquelético/irrigación sanguínea , Anciano , Análisis de Varianza , Medios de Contraste , Estudios de Factibilidad , Humanos , Angiografía por Resonancia Magnética/métodos , Persona de Mediana Edad , Músculo Esquelético/fisiopatología , Enfermedad Arterial Periférica/patología , Estudios Prospectivos
9.
J Vasc Surg ; 59(2): 419-26, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24080129

RESUMEN

OBJECTIVE: To assess alterations in the regional perfusion and oxygenation of the calf muscles in individuals with diabetes. METHODS: Age-matched individuals with (n = 5) and without diabetes (n = 6) were investigated. Skeletal muscle perfusion, oxygen extraction fraction, and oxygen consumption rate were measured by newly developed noncontrast magnetic resonance imaging (MRI) techniques. The subjects lay supine on the MRI table with their foot firmly strapped to a custom-built isometric exercise device. The measurements were performed at rest and during an isometric plantar flexion muscle contraction. RESULTS: Individuals without diabetes had up to a 10-fold increase in muscle perfusion, 25% elevation in muscle oxygen extraction fraction, and a 12-fold increase in oxygen consumption rate in the calf during the plantar flexion isometric contraction. In patients with diabetes, the increases in these parameters were only up to sixfold, 2%, and sixfold, respectively. Exercise oxygen consumption rate was inversely associated with blood HbA1c levels (r(2) = .91). CONCLUSIONS: This is the first study to quantify regional skeletal muscle oxygenation in patients with diabetes using noncontrast MRI and warrants additional study. Attenuation of perfusion and oxygenation during exercise may have implications for understanding diabetic complications in the lower extremities.


Asunto(s)
Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 2/diagnóstico , Angiopatías Diabéticas/diagnóstico , Hemodinámica , Imagen por Resonancia Magnética , Músculo Esquelético/irrigación sanguínea , Consumo de Oxígeno , Imagen de Perfusión/métodos , Anciano , Biomarcadores/sangre , Estudios de Casos y Controles , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/fisiopatología , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/fisiopatología , Angiopatías Diabéticas/sangre , Angiopatías Diabéticas/fisiopatología , Estudios de Factibilidad , Hemoglobina Glucada/metabolismo , Humanos , Contracción Isométrica , Pierna , Persona de Mediana Edad , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiopatología , Posicionamiento del Paciente , Proyectos Piloto , Flujo Sanguíneo Regional , Posición Supina
10.
Gait Posture ; 112: 159-166, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38797052

RESUMEN

BACKGROUND: Decreased muscle volume and increased muscle-associated adipose tissue (MAAT, sum of intra and inter-muscular adipose tissue) of the foot intrinsic muscle compartment are associated with deformity, decreased function, and increased risk of ulceration and amputation in those with diabetic peripheral neuropathy (DPN). RESEARCH QUESTION: What is the muscle quality (normal, abnormal muscle, and adipose volumes) of the DPN foot intrinsic compartment, how does it change over time, and is muscle quality related to gait and foot function? METHODS: Computed tomography was performed on the intrinsic foot muscle compartment of 45 subjects with DPN (mean age: 67.2 ± 6.4 years) at baseline and 3.6 years. Images were processed to obtain volumes of MAAT, highly abnormal, mildly abnormal, and normal muscle. For each category, annual rates of change were calculated. Paired t-tests compared baseline and follow-up. Foot function during gait was assessed using 3D motion analysis and the Foot and Ankle Ability Measure. Correlations between muscle compartment and foot function during gait were analyzed using Pearson's correlations. RESULTS: Total muscle volume decreased, driven by a loss of normal muscle and mildly abnormal muscle (p<0.05). MAAT and the adipose-muscle ratio increased. At baseline, 51.5% of the compartment was abnormal muscle or MAAT, increasing to 55.0% at follow-up. Decreased total muscle volume correlated with greater midfoot collapse during gait (r = -0.40, p = 0.02). Greater volumes of highly abnormal muscle correlated with a lower FAAM score (r = -0.33, p = 0.03). SIGNIFICANCE: Muscle volume loss may progress in parallel with MAAT accumulation, impacting contractile performance in individuals with DPN. Only 48.5% of the DPN intrinsic foot muscle compartment consists of normal muscle and greater abnormal muscle is associated with worse foot function. These changes identify an important target for rehabilitative intervention to slow or prevent muscle deterioration and poor foot outcomes.


Asunto(s)
Neuropatías Diabéticas , Músculo Esquelético , Tomografía Computarizada por Rayos X , Humanos , Anciano , Masculino , Femenino , Músculo Esquelético/diagnóstico por imagen , Músculo Esquelético/fisiopatología , Neuropatías Diabéticas/fisiopatología , Neuropatías Diabéticas/diagnóstico por imagen , Persona de Mediana Edad , Tejido Adiposo/diagnóstico por imagen , Pie/diagnóstico por imagen , Pie/fisiopatología , Marcha/fisiología
11.
J Magn Reson Imaging ; 38(5): 1083-93, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23450691

RESUMEN

PURPOSE: To describe a semi-automated program that will segment subcutaneous fat, muscle, and adipose tissue in the foot using MR imaging, determine the reliability of the program between and within raters, and determine the validity of the program using MR phantoms. MATERIALS AND METHODS: MR images were acquired from 19 subjects with and without diabetes and peripheral neuropathy. Two raters segmented and measured volumes from single MR slices at the forefoot, midfoot, and hindfoot at two different times. Intra- and inter-rater correlation coefficients were determined. Muscle and fat MR phantoms of known volumes were measured by the program. RESULTS: Most ICC reliability values were over 0.950. Validity estimates comparing MR estimates and known volumes resulted in r(2) values above 0.970 for all phantoms. The root mean square error was less than 5% for all phantoms. CONCLUSION: Subcutaneous fat, lean muscle, and adipose tissue volumes in the foot can be quantified in a reliable and valid way. This program can be applied in future studies investigating the relationship of these foot structures to functions in important pathologies, including the neuropathic foot or other musculoskeletal problems.


Asunto(s)
Tejido Adiposo/patología , Pie Diabético/patología , Imagenología Tridimensional/métodos , Músculo Esquelético/patología , Técnica de Sustracción , Femenino , Pie/patología , Humanos , Imagen por Resonancia Magnética/instrumentación , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Fantasmas de Imagen , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
12.
Arch Phys Med Rehabil ; 94(5): 829-38, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23276801

RESUMEN

OBJECTIVE: To determine the effects of weight-bearing (WB) versus nonweight-bearing (NWB) exercise for persons with diabetes mellitus (DM) and peripheral neuropathy (PN). DESIGN: Randomized controlled trial with evaluations at baseline and after intervention. SETTING: University-based physical therapy research clinic. PARTICIPANTS: Participants with DM and PN (N=29) (mean age ± SD, 64.5±12.5y; mean body mass index [kg/m(2)] ± SD, 35.5±7.3) were randomly assigned to WB (n=15) and NWB (n=14) exercise groups. All participants (100%) completed the intervention and follow-up evaluations. INTERVENTIONS: Group-specific progressive balance, flexibility, strengthening, and aerobic exercise conducted sitting or lying (NWB) or standing and walking (WB) occurred 3 times a week for 12 weeks. MAIN OUTCOME MEASURES: Measures included the 6-minute walk distance (6MWD) and daily step counts. Secondary outcome measures represented domains across the International Classification of Functioning, Disability and Health. RESULTS: The WB group showed greater gains than the NWB group over time on the 6MWD and average daily step count (P<.05). The mean and 95% confidence intervals (CIs) between-group difference over time was 29m (95% CI, 6-51) for the 6MWD and 1178 (95% CI, 150-2205) steps for the average daily step count. The NWB group showed greater improvements than the WB group over time in hemoglobin A1c values (P<.05). CONCLUSIONS: The results of this study indicate the ability of this population with chronic disease to increase 6MWD and daily step count with a WB exercise program compared with an NWB exercise program.


Asunto(s)
Diabetes Mellitus Tipo 2/complicaciones , Pie Diabético/etiología , Neuropatías Diabéticas/rehabilitación , Limitación de la Movilidad , Entrenamiento de Fuerza , Caminata/fisiología , Anciano , Análisis de Varianza , Diabetes Mellitus Tipo 2/fisiopatología , Pie Diabético/prevención & control , Neuropatías Diabéticas/complicaciones , Neuropatías Diabéticas/fisiopatología , Prueba de Esfuerzo , Femenino , Pie/fisiopatología , Humanos , Hipoestesia/etiología , Hipoestesia/fisiopatología , Masculino , Persona de Mediana Edad , Entrenamiento de Fuerza/efectos adversos , Soporte de Peso
13.
J Orthop Res ; 41(10): 2329-2338, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-36324161

RESUMEN

Quantitative magnetic resonance imaging (qMRI) measures have provided insights into the composition, quality, and structure-function of musculoskeletal tissues. Low signal-to-noise ratio has limited application to tendon. Advances in scanning sequences and sample positioning have improved signal from tendon allowing for evaluation of structure and function. The purpose of this study was to elucidate relationships between tendon qMRI metrics (T1, T2, T1ρ and diffusion tensor imaging [DTI] metrics) with tendon tissue mechanics, collagen concentration and organization. Sixteen human Achilles tendon specimens were collected, imaged with qMRI, and subjected to mechanical testing with quantitative polarized light imaging. T2 values were related to tendon mechanics [peak stress (rsp = 0.51, p = 0.044), equilibrium stress (rsp = 0.54, p = 0.033), percent relaxation (rsp = -0.55, p = 0.027), hysteresis (rsp = -0.64, p = 0.007), linear modulus (rsp = 0.67, p = 0.009)]. T1ρ had a statistically significant relationship with percent relaxation (r = 0.50, p = 0.048). Collagen content was significantly related to DTI measures (range of r = 0.56-0.62). T2 values from a single slice of the midportion of human Achilles tendons were strongest predictors of tendon tensile mechanical metrics. DTI diffusivity indices (mean diffusivity, axial diffusivity, radial diffusivity) were strongly correlated with collagen content. These findings build on a growing body of literature supporting the feasibility of qMRI to characterize tendon tissue and noninvasively measure tendon structure and function. Statement of Clinical Significance: Quantitative MRI can be applied to characterize tendon tissue and is a noninvasive measure that relates to tendon composition and mechanical behavior.


Asunto(s)
Tendón Calcáneo , Imagen de Difusión Tensora , Humanos , Imagen de Difusión Tensora/métodos , Imagen por Resonancia Magnética/métodos , Imagen de Difusión por Resonancia Magnética , Tendón Calcáneo/diagnóstico por imagen , Colágeno
14.
Front Pharmacol ; 14: 1246892, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38089057

RESUMEN

Recently, the Amazonian plant medicine "ayahuasca"-containing the psychedelic compound N,N-dimethyltryptamine (DMT) and numerous ß-carboline alkaloids, such as harmine-has been suggested to exhibit beneficial effects in patients with affective and other mental health disorders. Although ayahuasca ingestion is considered safe, its pharmacokinetics/pharmacodynamics and tolerability profile pose some challenges and may limit the clinical applicability in vulnerable patient populations. While overdosing and the admixture of intolerable plant constituents may explain some of the common adverse reactions, the peroral route of administration may represent another relevant source of gastro-intestinal intolerabilities and unpredictable pharmacokinetics across users. To overcome these challenges, the present work aimed at creating ayahuasca-analogue formulations with improved pharmacokinetics and tolerability profiles. To this end, we developed peroral formulas and compared them with parenteral formulas specifically designed to circumvent the gastro-intestinal tract. In more detail, peroral administration of a capsule (containing purified DMT and harmine) was tested against a combined administration of an oromucosal harmine tablet and an intranasal DMT spray at two dose levels in an open-label within-subject study in 10 healthy male subjects. Pharmacokinetic and pharmacodynamic profiles were assessed by means of continuous blood sampling, vital sign monitoring, and psychometric assessments. Common side effects induced by traditional herbal ayahuasca such as nausea, vomiting, and diarrhea were significantly attenuated by our DMT/harmine formulations. While all preparations were well tolerated, the combined buccal/intranasal administration of harmine and DMT yielded substantially improved pharmacokinetic profiles, indicated by significantly reduced variations in systemic exposure. In conclusion, the combined buccal/intranasal administration of harmine and DMT is an innovative approach that may pave the way towards a safe, rapid-acting, and patient-oriented administration of DMT/harmine for the treatment of affective disorders. Clinical Trial Registration: clinicaltrials.gov, identifier NCT04716335.

15.
Front Psychiatry ; 14: 1302559, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38264636

RESUMEN

Background: There is growing scientific evidence for the therapeutic benefits of the Amazonian plant-based psychedelic "ayahuasca" for neuropsychiatric disorders such as depression and anxiety. However, there are certain challenges when incorporating botanical ayahuasca into biomedical research and clinical therapy environments. Formulations inspired by ayahuasca, which contain specific and standardized active components, are a potential remedy. Methods: We investigated subjective acute and persisting effects of a novel formulation containing the reversible monoamine oxidase inhibitor harmine (orodispersible tablet containing 100 mg MAO-I) and N,N-dimethyltryptamine (incremental intranasal dosing of up to 100 mg DMT), compared with two other conditions, namely harmine alone and placebo, in a crossover RCT in 31 healthy male subjects. Results: DMT + harmine, but not harmine alone, induced a psychedelic experience assessed with the 5D-ASC rating scale [global score: F(2,60) = 80.21, p < 0.001] and acute experience sampling items over time, characterized by psychological insights [PIQ, F(2,58.5) = 28.514, p < 0.001], emotional breakthroughs [EBI, F(2,60) = 26.509, p < 0.001], and low scores on the challenging experience questionnaire [CEQ, F(2,60) = 12.84, p < 0.001]. Participants attributed personal and spiritual significance to the experience (GSR) with mainly positive persisting effects (PEQ) at 1- and 4-months follow-up. Acute drug effects correlated positively with persisting effects. We found no changes in trait measures of personality, psychological flexibility, or general well-being, and no increases in psychopathology (SCL-90-R) were reported. Discussion and Conclusion: Our results suggest that the experience induced by the standardized DMT + harmine formulation induces a phenomenologically rich psychedelic experience, demonstrates good psychological safety and tolerability, is well tolerated, and induces beneficial psychological processes that could possibly support psychotherapy. Further studies are required to investigate the psychotherapeutic potential in patients.

17.
Ann Vasc Surg ; 26(2): 242-9, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22050879

RESUMEN

BACKGROUND: The goal of rehabilitation following lower extremity amputation is to restore the highest level of independent function. As much as possible, this includes the functional use of a prosthetic device fitted to the residual limb. Early prosthetic fit depends, in turn, on rapid healing of the amputation site. METHODS: We hypothesized that compliance with a novel custom-designed amputation protection and compression system (CAPCS) to the residual limb can accelerate and improve the likelihood of successful prosthesis use. We conducted a retrospective study of all patients who were offered CAPCS by certified prosthetists (Hanger Prosthetics and Orthotics, Bethesda, MD) during the period between April 2004 and November 2009. Variables included age, sex, indication for amputation, and compliance with CAPCS. Compliance was defined as consistent observed wearing of the CAPCS as directed. The primary end point was the fitting of a prosthetic device to the amputated limb, with time to prosthetic fit being the secondary outcome. RESULTS: Out of 100 patients who were offered CAPCS (n = 100) during the study period, 76% were considered compliant (n = 76). Sixty five patients (65%) were ultimately fitted with prosthetic limbs. In multivariate analysis, we found that patients who had compliant use of CAPCS were significantly more likely to be successfully fit with prosthesis (72 vs. 42%, p = 0.005). At 100 days post amputation, the cumulative incidence of prosthesis fitting was significantly higher in CAPCS compliant patients (69.7 vs. 22.2%, p = 0.012). CONCLUSIONS: Compliant use of a CAPCS following amputation is associated with earlier and more frequent use of a prosthetic. Based on this limited data set, a conclusion can be drawn that the potential exists to significantly improve functional outcomes after amputation, but well-designed prospective studies are needed to confirm this association.


Asunto(s)
Amputación Quirúrgica , Miembros Artificiales , Vendajes , Extremidad Inferior/cirugía , Ajuste de Prótesis , Anciano , Amputación Quirúrgica/efectos adversos , Distribución de Chi-Cuadrado , Diseño de Equipo , Femenino , Humanos , Estimación de Kaplan-Meier , Modelos Logísticos , Masculino , Persona de Mediana Edad , Missouri , Análisis Multivariante , Oportunidad Relativa , Cooperación del Paciente , Proyectos Piloto , Presión , Modelos de Riesgos Proporcionales , Diseño de Prótesis , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Cicatrización de Heridas
18.
Foot Ankle Int ; 33(5): 363-70, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22735277

RESUMEN

BACKGROUND: High forefoot plantar pressure is associated with plantar ulcers in people with diabetes and peripheral neuropathy. The purpose of this pilot study was to determine the safety and efficacy of botulinum toxin A injected into the gastrocnemius-soleus muscles to reduce muscle strength and plantar pressure. METHODS: This double blind, randomized clinical trial studied 17 people with diabetes mellitus, peripheral neuropathy and a forefoot plantar ulcer. Subjects were randomized into one of three groups receiving gastrocnemius-soleus muscle injections on the involved side with; 1) Saline (n = 5, weight =99± 21 kg), 2) 200-units of Botox® (n = 7, weight = 101± 5 kg), or 3) 300-units of Botox® (n = 5, weight = 129± 22 kg). Botox® dose was converted to units/kg, the majority received between 1.9 and 2.4 units/kg (n = 11) and one 3.2 units/kg. Plantarflexor peak torque and forefoot peak plantar pressure were quantified prior and 2 weeks post-injection. RESULTS: There were no complications from the injections. Plantarflexor peak torque on the involved side increased in the placebo and 300 groups (3± 4 Nm and 6± 10 Nm, respectively) and decreased -8± 11 Nm in the 200 group. There was no relationship between units/kg of Botox® for each subject and change in plantarflexor peak torque. Forefoot peak plantar pressure did not change in the placebo and 300 groups (0± 11 and 0± 5 N/cm(2), respectively) and decreased -4± 16 N/cm2 (4%) for the 200 group. CONCLUSION: There were no adverse events associated with the Botox® injections. This study was unable to determine the dose to consistently reduce plantarflexor strength and forefoot plantar pressure. Additional research is needed to investigate diabetes mellitus specific physiological changes and their impact of BoNT-A effectiveness in order to guide appropriate dosing.


Asunto(s)
Toxinas Botulínicas Tipo A/uso terapéutico , Pie Diabético/prevención & control , Neuropatías Diabéticas/fisiopatología , Fuerza Muscular/efectos de los fármacos , Fármacos Neuromusculares/uso terapéutico , Pie Diabético/fisiopatología , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Antepié Humano/fisiopatología , Humanos , Inyecciones Intramusculares , Masculino , Persona de Mediana Edad , Fuerza Muscular/fisiología , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/fisiología , Proyectos Piloto , Presión , Estudios Prospectivos
19.
Foot (Edinb) ; 51: 101912, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35255403

RESUMEN

PURPOSE: Midfoot movement dysfunction, as measured by heel rise performance, is associated with midfoot deformity in people with diabetes and peripheral neuropathy. Understanding contributors of midfoot movement dysfunction may help clinicians understand deformity progression. The purpose of this study was to determine the factors associated with midfoot angle at peak heel rise. METHODS: The outcomes of fifty-eight participants with type 2 diabetes mellitus and peripheral neuropathy were analyzed. Midfoot (forefoot on hindfoot) sagittal kinematics during unilateral heel rise task were measured using 3-dimensional motion analysis. A multivariate linear regression model was used to predict midfoot sagittal movements at peak heel rise. Independent variables that were entered in the model were (in order of entry): age, body mass index, intrinsic foot muscle volume, and maximum available midfoot plantarflexion range of motion. Intrinsic foot muscle volume was obtained from magnetic resonance imaging and maximum available midfoot motion was measured during non-weightbearing plantarflexion using 3-dimensional motion analysis. RESULTS: Body mass index (R2 = 30.5%, p < 0.001) and maximum available midfoot plantarflexion range of motion (R2 = 10.9%, p = 0.001) were significant factors that accounted for 41.4% of variance of midfoot angle at peak heel rise, while age and intrinsic foot muscle volume were not significant predictors. CONCLUSIONS: Greater body mass index and less available midfoot plantarflexion range of motion were associated with greater midfoot movement dysfunction. These two significant predictors are potentially modifiable, suggesting possible improvements in midfoot movements with reduction in body weight and increasing midfoot plantarflexion range of motion. Health care professionals should consider patient's weight and joint motion when prescribing foot exercise(s) to prevent excessive midfoot collapse during weightbearing tasks.


Asunto(s)
Diabetes Mellitus Tipo 2 , Enfermedades del Sistema Nervioso Periférico , Fenómenos Biomecánicos/fisiología , Índice de Masa Corporal , Diabetes Mellitus Tipo 2/complicaciones , Pie/fisiología , Talón , Humanos , Rango del Movimiento Articular/fisiología
20.
J Womens Health Phys Therap ; 46(2): 100-108, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35757164

RESUMEN

Background: Women with urgency/frequency predominant lower urinary tract symptoms (UF-LUTS) may have elevated pelvic floor muscle (PFM) position at rest and limited mobility with PFM contraction and bearing down, but this has not been quantified. Objectives: To compare PFM position and mobility using transperineal ultrasound (TPUS) at rest, maximal PFM contraction (perineal elevation), and bearing down (perineal descent) in women with and without UF-LUTS. We hypothesized that women with UF-LUTS would demonstrate elevated resting position and decreased excursion of pelvic landmarks during contraction and bearing down as compared to women without UF-LUTS. Study Design: Case-control study. Methods: Women with UF-LUTS were matched 1:1 on age, body mass index and vaginal parity to women without UF-LUTS. TPUS videos were obtained during 3 conditions: rest, PFM contraction, and bearing down. Levator plate angle (LPA) and puborectalis length (PR length), were measured for each condition. Paired t-tests or Wilcoxon signed rank tests compared LPA and PR length between cases and controls. Results: 21 case-control pairs (42 women): Women with UF-LUTS demonstrated greater LPA at rest (66.8 ± 13.2 degrees vs 54.9 ± 9.8 degrees; P=0.006), and less PR lengthening from rest to bearing down (0.2 ± 3.1 mm vs 2.1 ± 2.9 mm; P=.03). Conclusion: Women with UF-LUTS demonstrated more elevated (cranioventral) position of the PFM at rest and less PR muscle lengthening with bearing down. These findings highlight the importance of a comprehensive PFM examination and possible treatment for women with UF-LUTS to include PFM position and mobility.

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