The effect of tibialis anterior weakness on foot drop and toe clearance in patients with facioscapulohumeral dystrophy.

BACKGROUND: Facioscapulohumeral dystrophy is a genetic disease characterized by progressive muscle weakness leading to a complex combination of postural instability, foot drop during swing and compensatory strategies during gait that have been related to an increased risk of falling. The aim is to assess the effect of tibialis anterior muscle weakness on foot drop and minimum toe clearance of patients with facioscapulohumeral dystrophy during gait. METHODS: Eight patients allocated to a subgroup depending on the severity of tibialis anterior muscle weakness, assessed by manual muscle testing (i.e., severe and mild weakness), and eight matched control participants underwent gait analysis at self-selected walking speeds. FINDINGS: Walking speed, for all facioscapulohumeral dystrophy patients, and step length, for patients with severe weakness only, were significantly decreased compared to control participants. Minimum toe clearance was similar across all groups, but its variability was increased only for patients with severe weakness. A greater foot drop was systematically observed for patients with severe weakness during swing and only in late swing for patients with mild weakness. Individual strategies to compensate for foot drop remain unclear and may depend on other muscle impairment variability. INTERPRETATION: Although all patients were able to control the average height of their foot trajectory during swing, patients with severe tibialis anterior muscle weakness exhibited increased foot drop and minimum toe clearance variability. Manual muscle testing is a simple, cheap and effective method to assess tibialis anterior muscle weakness and seems promising to identify facioscapulohumeral dystrophy patients with an increased risk of tripping.

[Validity of the motor function measurement scale when routinely used in the follow-up of adult outpatients in a neuromuscular center]. / Analyse de validité de la "Mesure de la fonction motrice" (MFM) en pratique de consultation adulte d'un centre de référence pour maladies neuromusculaires.

INTRODUCTION: The Motor Function Measure (MFM) is widely used to assess severity and progression of neuromuscular diseases. Validity was established in a group of patients aged 6-60 years with suspected or confirmed diagnosis of neuromuscular diseases, Duchenne Muscular Dystrophy being the most frequent diagnosis in the population tested. OBJECTIVES: Our aim was to check the validity of the MFM in a hospital department specialized in neuromuscular diseases in the follow-up of adult out-patients presenting a myopathy, such population being very different from the MFM validation group in terms of age and sub-groups of myopathy. METHODS: One hundred patients were randomly selected in the Reference Center for Neuromuscular Diseases of Nice (France) between 2005 and 2007. Were collected: the MFM score, manual muscular testing (MMT) of lower and upper limb, face and spine, Brooke and Vignos scores. MFM and its three dimensions D1 (standing position and transfers), D2 (axial and proximal limb motor function) and D3 (distal motor function) were compared to the other scores with the Spearman Correlation Coefficient and the Principal Component Analysis. RESULTS: Patients were aged 18-78 years. The most frequent diagnoses were Steinert's Muscular Dystrophy (DM1) and Facio-ScapuloHumeral Dystrophy (FSHD) (30% and 29%). MFM was significantly correlated to all other scores except for Face MMT. However, Face MMT was correlated to D1 and D2 in DM1 patients and to D2 in FSHD patients. DISCUSSION: Our results confirm the validity of the MFM in adult patients with muscular diseases. However, the MFM global score and its three dimensions D1, D2 and D3 are variously correlated with the facial and axial muscle testing. Therefore, we recommend using separately the three dimensions D1, D2, D3 (rather than the global score) and, if more accuracy is required, the facial and axial muscle testing.

[Functional scales and motor assessment in amyotrophic lateral sclerosis]. / Echelles fonctionnelles et évaluation des fonctions motrices dans la Sclérose Latérale Amyotrophique.

There is a need of standardized and quantitative clinical assessments of ALS patients receiving new treatments. Some clinical scales, that are based on patients interviews and/or on physical examination, allow to quantify the patient functional status over time. The ALSFRS has been validated for that purpose and is one the most commonly used scales in clinical trials. Its revised version (the ALSFRS-R) has recently shown excellent metric properties. Functional scales are part of the clinical evaluation of ALS patients, and complete the quantitative assessment of muscle strength, that includes the Manual Muscular Testing (MMT) and the Maximal Voluntary Isometric Contraction (MVIC). Readers will find in this article a (non-exhaustive) listing of functional and motor scales that can be useful both in clinical trials of experimental agents and in daily practice.

Development and validation of a motor function classification in patients with neuromuscular disease: the NM-score.

OBJECTIVE: To develop a classification for neuromuscular disease patients in each of the three motor function domains (D1: standing and transfers; D2: axial and proximal function; D3: distal function). MATERIALS AND METHODS: A draft classification was developed by a study group and then improved by qualitative validation studies (according to the Delphi method) and quantitative validation studies (content validity, criterion validity and inter-rater reliability). A total of 448 patients with genetic neuromuscular diseases participated in the studies. RESULTS: On average, it took 6.3minutes to rate a patient. The inter-rater agreement was good when the classification was based on patient observation or an interview with the patient (Cohen's kappa=0.770, 0.690 and 0.642 for NM-Score D1, D2 and D3 domains, respectively). Stronger correlations (according to Spearman's coefficient) with the respective "gold standard" classifications were found for NM-Score D1 (0.86 vs. the Vignos Scale and -0.88 vs. the Motor Function Measure [MFM]-D1) and NM-Score D2 (-0.7 vs. the Brooke Scale and 0.64 vs. MFM D2) than for NM-Score D3 (0.49 vs. the Brooke scale and -0.49 vs. MFM D3). DISCUSSION/CONCLUSIONS: The NM-Score is a reliable, reproducible outcome measure with value in clinical practice and in clinical research for the description of patients and the constitution of uniform patient groups (in terms of motor function).

Pain assessment in Charcot-Marie-Tooth (CMT) disease.

OBJECTIVE: The objective of our study was to describe and evaluate the prevalence of chronic pain in persons with Charcot-Marie-Tooth (CMT) disease during a multidisciplinary consultation at the Center of Reference for Neuromuscular Diseases. METHODOLOGY: This prospective study was conducted between 2008 and 2010, it was a partnership between a Center of Reference for Neuromuscular Diseases (Centre de référence des maladies neuromusculaires [CRMD]) and a Department for the Assessment and Treatment of Pain (Département d'évaluation et de traitement de la douleur [DETD]). The evaluation consisted in a complete assessment of each patient during the first multidisciplinary consultation, with a previously established diagnosis validated by genetic testing, by various specialists: neurologist, PM&R physician, pain management specialist and physiotherapist. The evaluation tools used were Visual Analogical Scale (VAS), Hospital Anxiety and Depression Scale (HAD), DN4 scale, Neuropathic Pain Symptom Inventory (NPSI) (if DN4≥4), Pain Questionnaire of Saint Antoine (QDSA) (if DN4<4), body representation to define the painful areas, Overall Neuropathy Limitations Scale (ONLS), Medical Research Council scale (MRC), Short Questionnaire on Pain (QCD), VAS during transfers, self-care, getting dressed and physiotherapy sessions and quantified use of analgesics. RESULTS: A total of 50 patients were included (28 women, 22 men); two patients (one man and one woman) were discarded from the study because of missing pain assessment data. Mean age was 47years (R: 14-85), in average the symptoms had been present for the past 20years (R: 0.3-68), most patients had little impairment, the mean MRC was 53 (R: 36-60), with CMT1A being predominant (CMT1A: 76.9%, CMTX: 13.5%, CMT2: 5.8%, CMT4: 3.8%). It is noted that 65.4% of patients reported some pain with a mean duration of pain at 140months (R: 5-660). The mean VAS was 5.5 (R: 1-10), greater than 4 in 79.4% of cases, requiring the use of analgesics in 38.4% of cases (step 1: 60%, step 2: 40% on the WHO pain relief ladder). The predominant location of the pain was distal, peripheral and symmetric (64.7%); furthermore the feet were affected in 80% of cases. DN4 was positive in 40.6% of painful patients. In 62.5% of the cases, the pain did not have an underlying mechanical origin. The emotional impact remained quite modest (HAD: A=8; D=5). Patients with CMT1A seemed less affected by pain (P=0.03). CONCLUSION: This original study describes the pain in patients with CMT disease during a primary multidisciplinary consultation. We see that in 66% of cases, patients do report some pain, this pain is usually moderate, preferentially located in the extremities and is symmetric. In 62.5% of cases, the pain has a neuromuscular origin with a positive DN4 in 50% of cases in this etiology. In our study, patients with CMT1A report less pain than patients with other CMT types. This disease being quite rare (rare disease), the number of patients did not allow us to bring up statistically significant results. The pain must be thoroughly screened for because of its frequency in persons with CMT.