Characterizing the face in facioscapulohumeral muscular dystrophy.

OBJECTIVE: To evaluate facial weakness in patients with FSHD to better define clinical signs, and pilot a facial weakness severity score. METHODS: 87 FSHD patients and 55 controls were video recorded while performing seven facial tasks. The videos were assessed by three independent examiners to compile an overview of signs of facial weakness. Next, videos were semi-quantitatively assessed using a newly developed 4-point facial weakness score (FWS). This score was evaluated and correlated to other FSHD disease characteristics. RESULTS: Patients had lower scores on the total FWS than controls (mean score 43 ± 28, range 4-118, vs 14 ± 9, range 0-35, p < 0.001) and on all seven individual facial tasks (all p < 0.001). 54% of patients had FWS scores outside the range of controls. Patients had more asymmetry between the left and right side of the face than controls. About 10% of the patients had very mild facial weakness. These were mostly males (89%) with longer D4Z4 repeat sizes of 7-9 units. More severe facial weakness correlated to more severe overall disease severity and shorter D4Z4 repeat size, but not to disease duration. Interobserver agreement for the FWS between three raters was low with a Fleiss Kappa of 0.437. CONCLUSION: This study provides an overview of the clinical spectrum of facial weakness and its relation to other disease characteristics. The 4-point scale we introduced to grade the severity of facial weakness enables correlation of facial weakness to disease characteristics, but is not suited as clinical outcome measure for longitudinal studies.

Epidemiology and pathophysiology of falls in facioscapulohumeral disease.

BACKGROUND AND AIMS: Muscle weakness is a potentially important, yet poorly studied, risk factor for falls. Detailed studies of patients with specific myopathies may shed new light on the relation between muscle weakness and falls. Here falls in patients with facioscapulohumeral disease (FSHD) who suffered from lower limb muscle weakness were examined. This study provides insights into the prevalence, relevance and pathophysiology of falls in FSHD. METHODS: A validated questionnaire was used as well as a prospective 3 month follow-up to examine the prevalence, circumstances and consequences of falls in 73 patients with FSHD and 49 matched healthy controls. In a subgroup of 28 subjects, muscle strength was also examined and balance was assessed electrophysiologically using body worn gyroscopes. RESULTS: In the questionnaire, 30% of the patients reported falling at least once a month whereas none of the controls did. Injuries occurred in almost 70% of the patients. The prospective study showed that patients fell mostly at home, mainly due to intrinsic (patient related) causes, and usually in a forward direction. Fallers were unstable while climbing stairs, rising from a chair and standing with eyes closed whereas non-fallers had normal balance control. Frequent fallers had greater muscle weakness than infrequent fallers. CONCLUSION: These findings demonstrate the high prevalence and clinical relevance of falls in FSHD. The relation between muscle weakness and instability among fallers is also highlighted. Because patients fell mainly at home, fall prevention strategies should focus on home adaptations. As mainly intrinsic causes underlie falls, the impact of adopting balance strategies or balance training should be explored in this patient group.

High specificity of myositis specific autoantibodies for myositis compared with other neuromuscular disorders.

Myositis specific autoantibodies (MSAs) are proven to be specific for myositis compared with other inflammatory connective tissue diseases. Their specificity compared, however, with other neuromuscular disorders, which are included in the differential diagnosis of patients in whom the diagnosis myositis is under consideration, is unknown. We prospectively screened sera from 107 patients with various neuromuscular disorders for the most common MSAs and compared the results with the findings in a group of 97 myositis patients, published previously. Special attention was paid to patients with facioscapulohumeral muscular dystrophy (FSHD), an autosomal dominant muscle disease with marked inflammation in skeletal muscle tissue. Only one patient in the neuromuscular disorders group tested positive for an MSA, compared with 41 in the myositis group, resulting in a specificity of 99%. None of the FSHD patients tested positive. We conclude that the tested MSAs are highly specific for myositis and that they are not merely associated with muscle inflammation.