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AIM: This study aimed to determine whether symptoms can reliably predict a major disorder of oesophageal motility as assessed by conventional water perfusion manometry. METHODS: Data from patients who underwent conventional water perfusion oesophageal manometry and a pre-manometry questionnaire between October 1998 and August 2018 were extracted from a database. Clinical features (dysphagia, chest pain, regurgitation, dysphagia to a bread challenge) and combinations of these clinical features were compared to manometric diagnoses. RESULTS: Data from 546 patients were analysed. Thirty-three (6%) patients had a major disorder of motility, and 513 (94%) had normal manometry or a minor disorder of motility. 'Any dysphagia' (dysphagia as a symptom or dysphagia to a bread challenge) or 'chest pain' was experienced by all patients with a major disorder of motility and 435 of 513 patients with normal manometry or a minor disorder of motility (p=0.009). Sensitivity was 100%, and specificity was 15%, in identifying patients with a major disorder of motility using symptom combinations and a bread challenge. CONCLUSION: Symptoms and provoked dysphagia to bread were able to predict patients with a major disorder of oesophageal motility with a sensitivity of 100%. However, as specificity was 15%, confirmation with manometry is indicated if possible.
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Trastornos de la Motilidad Esofágica/diagnóstico , Manometría/métodos , Dolor en el Pecho/etiología , Trastornos de Deglución/etiología , Femenino , Humanos , Reflujo Laringofaríngeo/etiología , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Sensibilidad y Especificidad , AguaRESUMEN
BACKGROUND: Definitive chemoradiation for oesophageal squamous cell carcinoma (SCC) is the first-line treatment in many centres. However, it is not without morbidity. We assess outcomes for patients treated with definitive chemoradiotherapy and radiotherapy. METHODS: A retrospective review of a prospectively maintained database (Radiotherapy Department, Canterbury District Health Board) was undertaken. All patients who underwent definitive radiotherapy for oesophageal SCC between October 1996 and April 2015 were included. RESULTS: Sixty patients underwent chemoradiotherapy with curative intent and 17 underwent definitive radiotherapy with curative intent. Median age was 69 years (44-84 years) for those undergoing chemoradiotherapy and 73 years (36-85 years) for those who underwent definitive radiotherapy. Tumour location in all patients was upper third in 14 (18%), middle third in 39 (51%), lower third in 22 (29%) cases and junctional tumour in two (3%). Staging information was complete for 73 of 77 patients (stage I 16/77 (21%), stage II 40/77 (52%), stage III 17/77 (22%)). Median dose of external beam radiotherapy for those who underwent definitive chemotherapy was 50.4 Gy (30-63 Gy) and 60 Gy (50-64 Gy) for definitive radiotherapy. Median length of follow-up was 39 months (range 4-120 months). Strictures developed in 58% of all patients (52% chemoradiotherapy and 76% definitive radiotherapy). Twenty-four (32%) patients were dilated and 14 (18%) stented. The chemoradiotherapy group had higher 5-year survival than definitive radiotherapy group (34% versus 6%, P = 0.0034). CONCLUSION: Oesophageal SCC treated with chemoradiation has a 5-year survival rate of 34%. Post-treatment strictures occur in 52% of patients with chemoradiotherapy and 76% with definitive radiotherapy.
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Quimioradioterapia/efectos adversos , Constricción Patológica/inducido químicamente , Carcinoma de Células Escamosas de Esófago/tratamiento farmacológico , Carcinoma de Células Escamosas de Esófago/radioterapia , Radioterapia/efectos adversos , Adulto , Cuidados Posteriores/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/patología , Estudios de Casos y Controles , Quimioradioterapia/mortalidad , Terapia Combinada , Constricción Patológica/patología , Constricción Patológica/terapia , Trastornos de Deglución/diagnóstico , Trastornos de Deglución/etiología , Neoplasias Esofágicas/mortalidad , Carcinoma de Células Escamosas de Esófago/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Nueva Zelanda/epidemiología , Radioterapia/mortalidad , Dosificación Radioterapéutica , Estudios Retrospectivos , Stents/efectos adversos , Tasa de SupervivenciaAsunto(s)
Adenocarcinoma/diagnóstico por imagen , Aorta Torácica/diagnóstico por imagen , Trastornos de Deglución/diagnóstico , Neoplasias Esofágicas/diagnóstico por imagen , Ganglios Linfáticos/patología , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/patología , Adenocarcinoma/cirugía , Anciano , Anastomosis Quirúrgica/métodos , Aorta Torácica/anomalías , Quimioterapia Adyuvante/métodos , Trastornos de Deglución/etiología , Ecocardiografía/métodos , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/cirugía , Esofagectomía/métodos , Gastroscopía/métodos , Humanos , Ganglios Linfáticos/cirugía , Metástasis Linfática/patología , Masculino , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Resultado del Tratamiento , Pérdida de PesoRESUMEN
An 85-year-old female presented to hospital with haemoptysis. She underwent investigations which confirmed oesophageal submucosal haematoma. Oesophageal haematoma along with Mallory-Weiss and Boerhaave's syndromes make up acute mucosal injury of the oesophagus. It can be managed conservatively in the majority of cases.
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Antitrombinas/efectos adversos , Dabigatrán/efectos adversos , Perforación del Esófago/diagnóstico por imagen , Hemorragia Gastrointestinal/diagnóstico por imagen , Hematoma/diagnóstico por imagen , Enfermedades del Mediastino/diagnóstico por imagen , Anciano de 80 o más Años , Fibrilación Atrial , Femenino , Hemorragia Gastrointestinal/complicaciones , Hemorragia Gastrointestinal/etiología , Gastroscopía , Hematoma/etiología , Hemoptisis/etiología , Humanos , Tomografía Computarizada por Rayos X , Vómitos/etiologíaRESUMEN
BACKGROUND & AIMS: Achalasia is a disorder of esophageal motility with a reported incidence of 0.5 to 1.6 per 100,000 persons per year in Europe, Asia, Canada, and America. However, estimates of incidence values have been derived predominantly from retrospective searches of databases of hospital discharge codes and personal communications with gastroenterologists, and are likely to be incorrect. We performed a cohort study based on esophageal manometry findings to determine the incidence of achalasia in South Australia. METHODS: We collected data from the Australian Bureau of Statistics on the South Australian population. Cases of achalasia diagnosed by esophageal manometry were identified from the 3 adult manometry laboratory databases in South Australia. Endoscopy reports and case notes were reviewed for correlations with diagnoses. The annual incidence of achalasia in the South Australian population was calculated for the decade 2004 to 2013. Findings were standardized to those of the European Standard Population based on age. RESULTS: The annual incidence of achalasia in South Australia ranged from 2.3 to 2.8 per 100,000 persons. The mean age at diagnosis was 62.1 ± 18.1 years. The incidence of achalasia increased with age (Spearman rho, 0.95; P < .01). The age-standardized incidence ranged from 2.1 (95% CI, 1.8-2.3) to 2.5 (95% CI, 2.2-2.7). CONCLUSIONS: Based on a cohort study of esophageal manometry, we determined the incidence of achalasia in South Australia to be 2.3 to 2.8 per 100,000 persons and to increase with age. South Australia's relative geographic isolation and the population's access to manometry allowed for more accurate identification of cases than hospital code analyses, with a low probability of missed cases.
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Acalasia del Esófago/diagnóstico , Acalasia del Esófago/epidemiología , Manometría/métodos , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Australia del Sur/epidemiología , Adulto JovenRESUMEN
Achalasia is a motility disorder encountered by surgeons during the investigation and treatment of dysphagia. Recent advances in manometry technology, a widely accepted new classification system and a new treatment rapidly gaining international acceptance, have changed the working knowledge required to successfully manage patients with achalasia. We review the Chicago classification subtypes of achalasia with type II achalasia being a predictor of success and type III achalasia a predictor of treatment failure. We review per-oral endoscopic myotomy as an emerging treatment option and its potential for improving the treatment of type III achalasia.
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Acalasia del Esófago/cirugía , Esfínter Esofágico Inferior/cirugía , Esofagoscopía , Cirugía Endoscópica por Orificios Naturales/métodos , Acalasia del Esófago/diagnóstico , Acalasia del Esófago/fisiopatología , Esfínter Esofágico Inferior/diagnóstico por imagen , Esfínter Esofágico Inferior/fisiopatología , Humanos , Manometría , PresiónRESUMEN
We present a case of an 86-year-old male who presented with severe pneumonia in the context of having undergone radiotherapy and then an oesophageal stent insertion for palliation of oesophageal cancer. He was diagnosed with a tracheo-oesophageal fistula (TOF) which was successfully managed by deploying a second stent within the first stent.
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OBJECTIVE: The purpose of this study was to determine if there is an association between admission interview score and subsequent academic and clinical performance, in a four-year undergraduate physiotherapy course. DESIGN: Retrospective observational study. PARTICIPANTS: 141 physiotherapy students enrolled in two entry year groups. OUTCOME MEASURES: Individual student performance in all course units, practical examinations, clinical placements as well as year level and overall Grade Point Average. Predictor variables included admission interview scores, admission academic scores and demographic data (gender, age and entry level). RESULTS: Interview score demonstrated a significant association with performance in three of six clinical placements through the course. This association was stronger than for any other admission criterion although effect sizes were small to moderate. Further, it was the only admission score to have a significant association with overall Clinical Grade Point Average for the two year groups analysed (r=0.322). By contrast, academic scores on entry showed significant associations with all year level Grade Point Averages except Year 4, the clinical year. CONCLUSIONS: This is the first study to review the predictive validity of an admission interview for entry into a physiotherapy course in Australia. The results show that performance in this admission interview is associated with overall performance in clinical placements through the course, while academic admission scoring is not. These findings suggest that there is a role for both academic and non-academic selection processes for entry into physiotherapy.
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Competencia Clínica , Educación Profesional/métodos , Modalidades de Fisioterapia/educación , Criterios de Admisión Escolar , Adulto , Factores de Edad , Australia , Evaluación Educacional , Femenino , Personal de Salud/educación , Humanos , Masculino , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Medición de Riesgo , Factores Sexuales , Estudiantes/estadística & datos numéricos , Adulto JovenRESUMEN
BACKGROUND: Ultrasound (US) is used in the workup of thyroid nodules. Ultrasonographic characteristics, such as an ill-defined margin, hypoechoicity or fine calcifications, are known to be associated with malignant thyroid lesions. The association between these characteristics and the risk of malignancy has been reported predominantly from series published where US is performed in radiology departments. Clinician-performed ultrasound (CPU) is increasingly being used as a modality, although there is little published literature validating this practice. METHOD: A prospectively collected database of known ultrasonographic characteristics of malignancy as determined by CPU on thyroid nodules is reported and correlated against adequate cytology or operative histopathology. RESULTS: In total, 157 thyroid nodules (28 malignant, 129 benign) were included and characteristics of poorly defined capsule (sensitivity 46%, specificity 91%), absence of halo (sensitivity 54%, specificity 80%), hypoechoicity (sensitivity 79%, specificity 54%), heterogeneity (sensitivity 64%, specificity 68%), fine calcifications (sensitivity 36%, specificity 95%) and central blood supply (sensitivity 71%, specificity 69%) were found to be associated with malignant thyroid nodules. Negative-predictive values (NPVs) for these characteristics were consistently high (89%, 89%, 92%, 90%, 87% and 94%, respectively). DISCUSSION: These results are consistent with the previously published datasets of ultrasonographic characteristics of malignancy and validate the use of CPU. The consistently high NPV suggests that the absence of ultrasonographic characteristics of malignancy correlates well with benign lesions. CPU is a reliable and useful tool in the hands of surgeons assessing and following potentially malignancy thyroid nodules.
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Nódulo Tiroideo/diagnóstico por imagen , Humanos , Estudios Prospectivos , Neoplasias de la Tiroides/diagnóstico por imagen , Nódulo Tiroideo/patología , Ultrasonografía/métodosRESUMEN
BACKGROUND: Upper limb (UL) burns can result in significant loss of strength and physical function. The aim of this study was to establish the reliability and validity of grip strength dynamometry (GSD) for measuring burn-affected UL strength over time. METHODS: A retrospective sample of adult participants (n=89) with UL burns was obtained from Royal Perth Hospital. Data were compiled from assessments conducted at discharge, one, three, six and 12 months afer burn. Within-session reliability and validity was examined through multivariable analyses. RESULTS: GSD demonstrated within-session reliability for all investigated timepoints (ICC's≥0.87, p<0.0005.) Criterion validity was confirmed with GSD and QuickDASH being significantly associated in both right (b=0.17, p=0.002) and left (b=0.14, p=0.002) hands. Construct validity was demonstrated through significant association of GSD values with location of burn (p<0.35); time after burn (p<0.012); surgical intervention (p=0.003) and burn size (p<0.05). CONCLUSION: This study demonstrates that grip strength dynamometry is a reliable and valid outcome measure for measuring burn-affected UL strength from one month to one year after burn.
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Quemaduras/rehabilitación , Fuerza de la Mano/fisiología , Extremidad Superior/lesiones , Adulto , Quemaduras/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud/métodos , Recuperación de la Función/fisiología , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Adulto JovenRESUMEN
The physiological equivalents of power output maintenance and recovery during repeated-sprint exercise (RSE) remain to be fully elucidated. In an attempt to improve our understanding of the determinants of RSE performance we therefore aimed to determine its recovery following exhaustive exercise (which affected intramuscular and neural factors) concomitantly with those of intramuscular concentrations of adenosine triphosphate [ATP], phosphocreatine [PCr] and pH values and electromyography (EMG) activity (a proxy for net motor unit activity) changes. Eight young men performed 10, 6-s all-out sprints on a cycle ergometer, interspersed with 30 s of recovery, followed, after 6 min of passive recovery, by five 6-s sprints, again interspersed by 30 s of passive recovery. Biopsies of the vastus lateralis were obtained at rest, immediately after the first 10 sprints and after 6 min of recovery. EMG activity of the vastus lateralis was obtained from surface electrodes throughout exercise. Total work (TW), [ATP], [PCr], pH and EMG amplitude decreased significantly throughout the first ten sprints (P<0.05). After 6 min of recovery, TW during sprint 11 recovered to 86.3±7.7% of sprint 1. ATP and PCr were resynthesized to 92.6±6.0% and 85.3±10.3% of the resting value, respectively, but muscle pH and EMG amplitude remained depressed. PCr resynthesis was correlated with TW done in sprint 11 (râ=â0.79, P<0.05) and TW done during sprints 11 to 15 (râ=â0.67, P<0.05). There was a â¼2-fold greater decrease in the TW/EMG ratio in the last five sprints (sprint 11 to 15) than in the first five sprints (sprint 1 to 5) resulting in a disproportionate decrease in mechanical power (i.e., TW) in relation to EMG. Thus, we conclude that the inability to produce power output during repeated sprints is mostly mediated by intramuscular fatigue signals probably related with the control of PCr metabolism.
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Electromiografía , Ejercicio Físico , Concentración de Iones de Hidrógeno , Músculo Esquelético/fisiología , Fosfocreatina/biosíntesis , Humanos , Masculino , Metaboloma , Metabolómica , Factores de TiempoRESUMEN
BACKGROUND: Tissue inhibitor of metalloproteinase-1 (TIMP-1) has paradoxical multifunctional roles in tumorigenesis: inhibition of the catalytic activity of matrix metalloproteinases and apoptosis as well as promotion of angiogenesis and tumor growth. Elevated TIMP-1 levels have been associated with a poorer prognosis in multiple cancers. METHODS: Ethylenediaminetetraacetic acid plasma TIMP-1 was determined in 362 castration-resistant prostate cancer (PC) patients using a TIMP-1 enzyme-linked immunosorbent assay. All patients with castration-resistant PC and available plasma were identified from an institutional database. Overall survival was analyzed using the Kaplan-Meier method and Cox modeling on plasma TIMP-1 tertiles. RESULTS: Patients were evaluated in pilot (n = 60) and primary (n = 302) sets. Median follow-up from diagnosis was 5.8 and 6.6 years, respectively. Median plasma TIMP-1 levels were 335 and 183 ng/mL in the pilot and primary sets, respectively. Overall survival was significantly shorter with each higher tertile of TIMP-1 in both datasets (P<.001). For the primary cohort, hazard ratio of (HR) death and median survival by plasma TIMP-1 tertile levels were: low, HR 1.0, 43 months; middle, HR 1.7, 27 months; high, HR 2.4, 19 months. In the primary set, significant covariates in the adjusted Cox regression model were: TIMP-1 level (mid or high vs low tertile), prostate-specific antigen (>20 vs ≤20 ng/mL), alkaline phosphatase (>102 vs ≤102 U/L), Eastern Cooperative Oncology Group performance status (1 + vs 0), and Gleason score (7 or 8 vs ≤6). CONCLUSIONS: Elevated plasma TIMP-1 levels predicted decreased survival in metastatic castration-resistant PC patients, independent of known prognostic markers.
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Neoplasias de la Próstata/sangre , Inhibidor Tisular de Metaloproteinasa-1/sangre , Anciano , Castración , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Pronóstico , Neoplasias de la Próstata/mortalidad , Neoplasias de la Próstata/patologíaRESUMEN
AIMS: To determine changes in upper limb movement substructures that denote fluency of movement in children with cerebral palsy (CP) following lycra(®) splint wear. Secondarily, to explore the efficacy of lycra(®) splints for those with spastic and dystonic hypertonia. DESIGN: Randomised clinical trial whereby participants were randomised to parallel groups with waiting list control. METHOD: Sixteen children (mean age 11.5 years SD=2.2) with hypertonic upper limb involvement (13 hemiplegia, 4 quadriplegia) were recruited. Children were randomly allocated either to a control group or to wear the lycra(®) splint for a period of three months. Three-dimensional (3D) upper limb kinematics was used to assess four functional tasks at baseline, on initial lycra(®) splint application, three months after lycra(®) splint wear, and immediately after splint removal. Movement substructures of the motion of the wrist joint center were analysed. RESULTS: A significant difference was observed between baseline and three months of lycra(®) splint wear in the movement substructures; movement time, percentage of time and distance in primary movement, jerk index, normalised jerk and percentage of jerk in primary and secondary movements. The magnitude of changes in normalised jerk and the percentage of jerk in the primary movement from baseline to three months was greatest in children with dystonic hypertonia. CONCLUSIONS: The results indicate that lycra(®) arm splinting induced significant changes in movement substructures and motor performance in children with CP. This research demonstrates that fluency of movement can be quantified and is amenable to change with intervention.
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Brazo/fisiología , Parálisis Cerebral/fisiopatología , Distonía/fisiopatología , Férulas (Fijadores) , Niño , Femenino , Humanos , Masculino , Movimiento/fisiología , Espasticidad Muscular/fisiopatologíaRESUMEN
Tissue inhibitor of metalloproteinase-1 (TIMP-1) was evaluated in the pre-treatment serum of 55 newly diagnosed patients with symptomatic myeloma. TIMP-1 was elevated in 47% of patients and correlated with lytic bone disease and increased bone resorption. Importantly, TIMP-1 correlated with ISS stage (p=0.005) and was an independent prognostic covariate for survival [HR: 1.003 (1-1.006), p=0.004] in these patients who were all treated with novel agents (bortezomib and/or IMiDs) during their disease course. Our study provides evidence that pre-treatment serum TIMP-1 is associated with advanced myeloma and suggests the further evaluation of this molecule to better determine its prognostic potential in MM.
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Biomarcadores de Tumor/sangre , Mieloma Múltiple/sangre , Inhibidor Tisular de Metaloproteinasa-1/sangre , Anciano , Anciano de 80 o más Años , Antineoplásicos/uso terapéutico , Ácidos Borónicos/uso terapéutico , Bortezomib , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/mortalidad , Pronóstico , Pirazinas/uso terapéuticoRESUMEN
AIM: To determine the neuromuscular outcomes of an eccentric strength-training programme for children and adolescents with cerebral palsy (CP). METHOD: In this randomised, parallel-group trial with waiting control, 14 participants with CP (six males, eight females; mean age 11y, SD 2y range 9-15y), diagnosed with upper-limb spasticity were compared with 14 age- and sex-matched typically developing participants. Participants with CP completed a 6-week progressive resistance-strengthening programme, performing eccentric lengthening contractions of their upper limb three times a week. Data from dynamometer and surface electromyography (EMG) assessments included peak torque normalised to body mass (T/Bm), work normalised to body mass (W/Bm), angle at peak torque, curve width, and EMG activation. RESULTS: After training, children with CP had improved eccentric T/Bm (p=0.009) and W/Bm (p=0.009) to a level similar to that of the typically developing children. No change in angle of peak torque occurred, although curve width increased both concentrically (p=0.018) and eccentrically (p=0.015). EMG activity was elevated before training in children with CP but decreased with training to levels similar to those of the typically developing children. INTERPRETATION: With eccentric strength training, children with CP increased torque throughout range of motion. Results suggest that eccentric exercises may decrease co-contraction, improving net torque development. Eccentric actions may be important in the maintenance of the torque-angle relationship. These results have significant implications for the prescription of strength-training programmes for people with CP.
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Adaptación Fisiológica/fisiología , Parálisis Cerebral/fisiopatología , Parálisis Cerebral/rehabilitación , Fuerza Muscular/fisiología , Entrenamiento de Fuerza/métodos , Adolescente , Niño , Electromiografía/métodos , Femenino , Humanos , Masculino , Contracción Muscular/fisiología , Dinamómetro de Fuerza Muscular , Rango del Movimiento Articular/fisiología , TorqueRESUMEN
PURPOSE: This study compared linear (LP) and undulating periodization (UP) on strength changes in untrained women when total workload and average training intensity were matched by the end of training. METHODS: Twenty females (20 +/- 2 yr) were conditioned (3 wk) and assessed for one-repetition maximum squat (1RMSQ) and bench press (1RMBP) before being assigned to LP or UP training (9 wk), with training performed at 3 d.wk. Maximal strength, average power output during squat jumps with countermovement (SQJpwr) and bench press throws (BPTpwr), body mass, limb girth, and muscle cross-sectional area (CSA) were assessed at baseline (T1) and after every 3 wk (T2, T3, and T4) to differentiate the efficacy of LP and UP training. RESULTS: Both groups improved significantly (P < 0.05) in 1RMSQ (LP 34.8%, UP 41.2%), 1RMBP (LP 21.8%, UP 28.3%), SQJpwr (LP 10.4%, UP 9.5%), BPTpwr (LP 11.1%, UP 13.8%), arm girth (LP 1.14%, UP 1.73%), and thigh girth (LP 1.58%, UP 1.99%), with no significant difference between them. Muscle CSA for the LP group increased significantly at T2 before maintaining similar hypertrophic responses until T4, whereas the UP group recorded significant increments from T1 to T2 and T2 to T3, before stabilizing between T3 and T4. Pooled CSA increase was higher than previously found (6.8% at T2, 11.3% at T3, and 11.8% at T4). CONCLUSIONS: The comparison of LP and UP training with matched volume load and intensity suggests that both programs were equally adept in improving different strength qualities in active but untrained women. In addition, muscle hypertrophic responses were larger and occurred earlier than previously reported.
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Fuerza Muscular/fisiología , Aptitud Física/fisiología , Adolescente , Femenino , Humanos , Hipertrofia , Entrenamiento de Fuerza , Adulto JovenRESUMEN
Duchenne muscular dystrophy (DMD) is a genetic disorder in which muscle weakness and fragility contribute to ongoing muscle degeneration. Although exercise-induced muscle damage is associated with adaptation that protects normal muscle from further damage, exploiting this process to protect dystrophic muscle has been avoided for fear of inducing excessive muscle degeneration. However, muscle-specific over-expression of the class 1:Ea isoform of insulin-like growth factor-1 (IGF-1) reduces myofibre necrosis in dystrophic mdx mice (a model for DMD) and, therefore, may enhance the adaptation process in response to eccentric exercise. To test this hypothesis, we evaluated the effect of transgenic class 1:Ea IGF-1 over-expression on the susceptibility to muscle damage and subsequent adaptation in 12-week-old dystrophic mdx and non-dystrophic control mice. Experiments were conducted in vivo using a custom-built isokinetic mouse dynamometer to measure the deficit in joint torque (indicating muscle damage) after 20 maximal lengthening (eccentric) contractions. Adaptation to this damaging exercise was evaluated by repeating the protocol 7 days after the initial exercise. The over-expression of IGF-1 significantly increased the normalised joint torque in non-dystrophic mice and appeared to ameliorate the muscle weakness in dystrophic mice. All mice displayed a marked reduction in the susceptibility to muscle damage on day 7; however, this adaptation was unaffected by IGF-1, showing that IGF-1 does not protect the dystrophic muscles of adult mdx mice against damage resulting from maximal lengthening contractions.
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Factor I del Crecimiento Similar a la Insulina/fisiología , Distrofia Muscular Animal/terapia , Distrofia Muscular de Duchenne/terapia , Transgenes , Animales , Modelos Animales de Enfermedad , Expresión Génica , Terapia Genética , Factor I del Crecimiento Similar a la Insulina/genética , Factor I del Crecimiento Similar a la Insulina/uso terapéutico , Masculino , Ratones , Ratones Endogámicos mdx , Ratones Transgénicos , Contracción Muscular , Fatiga Muscular , Músculo Esquelético/patología , Músculo Esquelético/fisiopatología , Esfuerzo Físico/fisiologíaRESUMEN
PURPOSE: This study investigated the relationship between muscular strength about the knee and knee joint moments during gait in patients who had undergone arthroscopic partial meniscectomy (APM). METHODS: One hundred and two APM patients and 42 age-matched nonoperated controls underwent strength testing and three-dimensional gait analysis. Patients were divided into weak and normal subgroups and compared with controls for spatiotemporal, kinematic, and kinetic gait parameters. RESULTS: Spatiotemporal parameters, kinematics, and sagittal plane kinetics were similar between APM patients and controls. The APM group displayed weaker concentric knee extension and flexion strength compared with controls. The weak APM subgroup had an increased average and peak knee adduction moments over stance compared with the APM subgroup with normal strength levels and controls. The normal strength APM subgroup had a larger peak knee adduction moment in early stance compared with controls. CONCLUSION: Achieving normal lower limb muscle strength following APM appears important to resume normal frontal plane loading of the knee while walking.