Measurement of muscle strength and activity of upper limbs of non-ambulant patients with neuromuscular diseases is a major challenge. ActiMyo® is an innovative device that uses magneto-inertial ...sensors to record angular velocities and linear accelerations that can be used over long periods of time in the home environment. The device was designed to insure long-term stability and good signal to noise ratio, even for very weak movements. In order to determine relevant and pertinent clinical variables with potential for use as outcome measures in clinical trials or to guide therapy decisions, we performed a pilot study in non-ambulant neuromuscular patients. We report here data from seven Duchenne Muscular Dystrophy (DMD) patients (mean age 18.5 ± 5.5 years) collected in a clinical setting. Patients were assessed while wearing the device during performance of validated tasks (MoviPlate, Box and Block test and Minnesota test) and tasks mimicking daily living. The ActiMyo® sensors were placed on the wrists during all the tests. Software designed for use with the device computed several variables to qualify and quantify muscular activity in the non-ambulant subjects. Four variables representative of upper limb activity were studied: the rotation rate, the ratio of the vertical component in the overall acceleration, the hand elevation rate, and an estimate of the power of the upper limb. The correlations between clinical data and physical activity and the ActiMyo® movement parameters were analyzed. The mean of the rotation rate and mean of the elevation rate appeared promising since these variables had the best reliability scores and correlations with task scores. Parameters could be computed even in a patient with a Brooke functional score of 6. The variables chosen are good candidates as potential outcome measures in non-ambulant patients with Duchenne Muscular Dystrophy and use of the ActiMyo® is currently being explored in home environment.
ClinicalTrials.gov NCT01611597.
Upper limb evaluation of patients with Duchenne Muscular Dystrophy is crucially important to evaluations of efficacy of new treatments in non-ambulant patients. In patients who have lost ambulation, ...there are few validated and informative outcome measures. In addition, longitudinal data demonstrating sensitivity to clinical evolution of outcome measures over short-term periods are lacking.
We report here the results of a one-year multicenter study using specifically designed tools to assess grip, pinch strength, and hand function in wheelchair-bound patients. Our study assessed 53 non-ambulant patients with Duchenne muscular dystrophy aged 17.1 ± 4.8 years (range: 9 - 28.1 years). The average Brooke functional score of these patients was 4.6 ± 1.1. The average forced vital capacity was 44.5% predicted and 19 patients used non-invasive ventilation. Patients were assessed at baseline, 6 months, and one year using the Motor Function Measure and innovative devices (namely the MyoSet composed of MyoGrip, MyoPinch, and MoviPlate).
Our study confirmed preliminary data previously reported regarding feasibility of use and of reliability of the MyoSet and the correlation at baseline between distal strength and clinical outcomes such as FVC, Brooke score, age, and duration since loss of ambulation. A significant correlation was observed between the distal upper limb strength and clinical variables. The sensitive dynamometers (MyoGrip and MyoPinch) and MoviPlate captured a 12-month change in non-ambulant Duchenne muscular dystrophy patients of all ages.
ClinicalTrials.gov NCT00993161 NCT00993161.
Background
Natural history studies in neuromuscular disorders are vital to understand the disease evolution and to find sensitive outcome measures. We performed a longitudinal assessment of ...quantitative magnetic resonance imaging (MRI) and phosphorus magnetic resonance spectroscopy (31P MRS) outcome measures and evaluated their relationship with function in lower limb skeletal muscle of dysferlinopathy patients.
Methods
Quantitative MRI/31P MRS data were obtained at 3 T in two different sites in 54 patients and 12 controls, at baseline, and three annual follow‐up visits. Fat fraction (FF), contractile cross‐sectional area (cCSA), and muscle water T2 in both global leg and thigh segments and individual muscles and 31P MRS indices in the anterior leg compartment were assessed. Analysis included comparisons between patients and controls, assessments of annual changes using a linear mixed model, standardized response means (SRM), and correlations between MRI and 31P MRS markers and functional markers.
Results
Posterior muscles in thigh and leg showed the highest FF values. FF at baseline was highly heterogeneous across patients. In ambulant patients, median annual increases in global thigh and leg segment FF values were 4.1% and 3.0%, respectively (P < 0.001). After 3 years, global thigh and leg FF increases were 9.6% and 8.4%, respectively (P < 0.001). SRM values for global thigh FF were over 0.8 for all years. Vastus lateralis muscle showed the highest SRM values across all time points. cCSA decreased significantly after 3 years with median values of 11.0% and 12.8% in global thigh and global leg, respectively (P < 0.001). Water T2 values in ambulant patients were significantly increased, as compared with control values (P < 0.001). The highest water T2 values were found in the anterior part of thigh and leg. Almost all 31P MRS indices were significantly different in patients as compared with controls (P < 0.006), except for pHw, and remained, similar as to water T2, abnormal for the whole study duration. Global thigh water T2 at baseline was significantly correlated to the change in FF after 3 years (ρ = 0.52, P < 0.001). There was also a significant relationship between the change in functional score and change in FF after 3 years in ambulant patients (ρ = −0.55, P = 0.010).
Conclusions
This multi‐centre study has shown that quantitative MRI/31P MRS measurements in a heterogeneous group of dysferlinopathy patients can measure significant changes over the course of 3 years. These data can be used as reference values in view of future clinical trials in dysferlinopathy or comparisons with quantitative MRI/S data obtained in other limb‐girdle muscular dystrophy subtypes.
We conducted a prospective multinational study of muscle pathology using magnetic resonance imaging (MRI) in patients with limb-girdle muscular dystrophy 2I (LGMD2I). Thirty eight adult ambulant ...LGMD2I patients (19 male; 19 female) with genetically identical mutations (c.826C>A) in the fukutin-related protein (FKRP) gene were recruited. In each patient, T1-weighted (T1w) imaging was assessed by qualitative grading for 15 individual lower limb muscles and quantitative Dixon imaging was analysed on 14 individual lower limb muscles by region of interest analysis. We described the pattern and appearance of muscle pathology and gender differences, not previously reported for LGMD2I. Diffuse fat infiltration of the gastrocnemii muscles was demonstrated in females, whereas in males fat infiltration was more prominent in the medial than the lateral gastrocnemius (p = 0.05). In the anterior thigh of males, in contrast to females, median fat infiltration in the vastus medialis muscle (45.7%) exceeded that in the vastus lateralis muscle (11.2%) (p<0.005). MRI is non-invasive, objective and does not rely on patient effort compared to clinical and physical measures that are currently employed. We demonstrated (i) that the quantitative Dixon technique is an objective quantitative marker of disease and (ii) new observations of gender specific patterns of muscle involvement in LGMD2I.
On the basis of our previous work with triheptanoin, which provides key substrates to the Krebs cycle in the brain, we wished to assess its therapeutic effect in patients with glucose transporter ...type 1 deficiency syndrome (GLUT1-DS) who objected to or did not tolerate ketogenic diets.
We performed an open-label pilot study with three phases of 2 months each (baseline, treatment and withdrawal) in eight patients with GLUT1-DS (7-47 years old) with non-epileptic paroxysmal manifestations. We used a comprehensive patient diary to record motor and non-motor paroxysmal events. Functional (31)P-NMR spectroscopy was performed to quantify phosphocreatine (PCr) and inorganic phosphate (Pi) within the occipital cortex during (activation) and after (recovery) a visual stimulus.
Patients with GLUT1-DS experienced a mean of 30.8 (± 27.7) paroxysmal manifestations (52% motor events) at baseline that dropped to 2.8 (± 2.9, 76% motor events) during the treatment phase (p = 0.028). After withdrawal, paroxysmal manifestations recurred with a mean of 24.2 (± 21.9, 52% motor events; p = 0.043). Furthermore, brain energy metabolism normalised with triheptanoin, that is, increased Pi/PCr ratio during brain activation compared to the recovery phase (p = 0.021), and deteriorated when triheptanoin was withdrawn.
Treatment with triheptanoin resulted in a 90% clinical improvement in non-epileptic paroxysmal manifestations and a normalised brain bioenergetics profile in patients with GLUT1-DS.
NCT02014883.
A number of promising experimental therapies for Duchenne muscular dystrophy (DMD) are emerging. Clinical trials currently rely on invasive biopsies or motivation-dependent functional tests to assess ...outcome. Quantitative muscle magnetic resonance imaging (MRI) could offer a valuable alternative and permit inclusion of non-ambulant DMD subjects. The aims of our study were to explore the responsiveness of upper-limb MRI muscle-fat measurement as a non-invasive objective endpoint for clinical trials in non-ambulant DMD, and to investigate the relationship of these MRI measures to those of muscle force and function.
15 non-ambulant DMD boys (mean age 13.3 y) and 10 age-gender matched healthy controls (mean age 14.6 y) were recruited. 3-Tesla MRI fat-water quantification was used to measure forearm muscle fat transformation in non-ambulant DMD boys compared with healthy controls. DMD boys were assessed at 4 time-points over 12 months, using 3-point Dixon MRI to measure muscle fat-fraction (f.f.). Images from ten forearm muscles were segmented and mean f.f. and cross-sectional area recorded. DMD subjects also underwent comprehensive upper limb function and force evaluation.
Overall mean baseline forearm f.f. was higher in DMD than in healthy controls (p<0.001). A progressive f.f. increase was observed in DMD over 12 months, reaching significance from 6 months (p<0.001, n = 7), accompanied by a significant loss in pinch strength at 6 months (p<0.001, n = 9) and a loss of upper limb function and grip force observed over 12 months (p<0.001, n = 8).
These results support the use of MRI muscle f.f. as a biomarker to monitor disease progression in the upper limb in non-ambulant DMD, with sensitivity adequate to detect group-level change over time intervals practical for use in clinical trials. Clinical validity is supported by the association of the progressive fat transformation of muscle with loss of muscle force and function.
Spinal muscular atrophy (SMA) type III and IV are autosomal recessive, slowly progressive lower motor neuron syndromes. Nevertheless, wider cerebral involvement has been consistently reported in ...mouse models. The objective of this study is the characterisation of spinal and cerebral pathology in adult forms of SMA using multimodal quantitative imaging.
Twenty-five type III and IV adult SMA patients and 25 age-matched healthy controls were enrolled in a spinal cord and brain imaging study. Structural measures of grey and white matter involvement and diffusion parameters of white matter integrity were evaluated at each cervical spinal level. Whole-brain and region-of-interest analyses were also conducted in the brain to explore cortical thickness, grey matter density and tract-based white matter alterations.
In the spinal cord, considerable grey matter atrophy was detected between C2-C6 vertebral levels. In the brain, increased grey matter density was detected in motor and extra-motor regions of SMA patients. No white matter pathology was identified neither at brain and spinal level.
Adult forms of SMA are associated with selective grey matter degeneration in the spinal cord with preserved white matter integrity. The observed increased grey matter density in the motor cortex may represent adaptive reorganisation.
•(SMA) type 3 and 4 is a lower motor neuron syndrome. Nevertheless, wider involvement of the nervous system might be possible.•25 adults type 3 and 4 SMA patients were studied using brain and cervical spinal cord neuroimaging techniques.•Grey matter atrophy was observed in the spinal cord. No white matter degeneration was present at brain and spinal level.•Increased grey matter density was detected in cerebral motor regions and explained as compensatory mechanism.
•Physical activity at inclusion correlates with muscle strength and patient-reported physical functioning in myositis patients•Changes in physical activity are associated with improvement in strength ...and psychological status•Only major improvement in the ACR/EULAR response criteria is strongly associated with significant increase in physical activity
This study aimed to investigate the relationship between changes in clinical status on daily life physical activity (PA) in patients with idiopathic inflammatory myopathy (IIM).
Patients with dermatomyositis (DM), immune-mediated necrotizing myopathy (IMNM) or overlap myositis (OM) who presented either a new-onset or relapsing IIM, stable disease on maintenance therapy or were undergoing immunosuppressant tapering were included. Patients were evaluated at inclusion (V0), and at two follow-up visits (V1, 94±12 days from V0; V2, 96±17 days from V1). The American College of Rheumatology/European League against Rheumatism (ACR/EULAR) response criteria was recorded. PA assessed using 14-days raw accelerometry data gathered using a wrist-worn accelerometer after each visit (mean daily Euclidean norm minus 1 g (ENMO) was computed).
Fifty-five patients (16 OM, 27 IMNM and 12 DM) were included. At baseline, 67% of patients had an ENMO Z-score less than 1. At inclusion, ENMO mainly correlated with health assessment questionnaire score (HAQ, ρ=-0.51, p<0.01), manual muscle testing 8 (MMT8, ρ=0.42, p<0.01), creatinine level (ρ=0.41, p<0.01), and SF-36 physical functioning score (ρ=0.38, p<0.002). At follow-up, ENMO changes mainly correlated with changes in MMT8, HAQ, SF-36 fatigue, and depression score (all ρ>0.43, all p<0.001). Level of agreement between ACR/EULAR response criteria and changes in PA was 15, 45, and 90% for minimal (n = 13), moderate (n = 20), and major (n = 10) improvements, respectively.
Baseline PA levels and change in PA correlated with muscle strength and function, yet changes in PA were also influenced by psychological status. Only patients with major improvements on the ACR/EULAR criteria had significant increase in PA. Accelerometer may serve as an objective tool to define a clinically relevant real-life outcome.
Abstract Natural history studies in sporadic inclusion body myositis are of fundamental interest for future therapeutic trials. Previous works have demonstrated the particular relevance of knee ...extension strength in the follow-up of this disease. This work aimed to extend a preceding natural history over 9 months to a four year period. Thirteen patients were assessed using clinical and functional scales and dynamometry. Except wrist extension torque and manual muscle testing composite score, all the measurements presented a significant decline. The most important changes were observed for knee extension and ankle flexion and extension. The relative change in knee extension strength correlated with the level of strength at baseline. A non-linear correlation was found between 6-minute walk distance and knee extension strength. This study confirms that knee extension strength is particularly relevant to follow patients with sporadic inclusion body myositis. It also shows that a strength loss does not have linear consequences on motor ability. Finally strength and motor ability are complementing each other in the understanding of disease progression.
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