To investigate the frequency, details, and consequences of falls in patients with autosomal dominant spinocerebellar ataxias (SCAs) and to derive specific disease-related risk factors that are associated with an increased fall frequency. Two hundred twenty-eight patients with SCA1, SCA2, SCA3, or SCA6, recruited from the EuroSCA natural history study, completed a fall questionnaire that assessed the frequency, consequences, and several details of falls in the previous 12 months. Relevant disease characteristics were retrieved from the EuroSCA registry. The database of the natural history study provided the ataxia severity scores as well as the number and nature of non-ataxia symptoms. Patients (73.6%) reported at least one fall in the preceding 12 months. There was a high rate of fall-related injuries (74%). Factors that were associated with a higher fall frequency included: disease duration, severity of ataxia, the presence of pyramidal symptoms, the total number of non-ataxia symptoms, and the genotype SCA3. Factors associated with a lower fall frequency were: the presence of extrapyramidal symptoms (more specifically dystonia of the lower limbs) and the genotype SCA2. The total number of non-ataxia symptoms and longer disease duration were independently associated with a higher fall frequency in a logistic regression analysis, while the presence of extrapyramidal symptoms was independently associated with a lower fall frequency. Our findings indicate that, in addition to more obvious factors that are associated with frequent falls, such as disease duration and ataxia severity, non-ataxia manifestations in SCA play a major role in the fall etiology of these patients.

In a previous retrospective study, we demonstrated that falls are common and often injurious in dominant spinocerebellar ataxias (SCAs) and that nonataxia features play an important role in these falls. Retrospective surveys are plagued by recall bias for the presence and details of prior falls. We therefore sought to corroborate and extend these retrospective findings by means of a prospective extension of this fall study. 113 patients with SCA1, SCA2, SCA3 or SCA6, recruited from the EuroSCA natural history study, were asked to keep a fall diary in between their annual visits to the participating centres. Additionally, patients completed a detailed questionnaire about the first three falls, to identify specific fall circumstances. Relevant disease characteristics were retrieved from the EuroSCA registry. 84.1% of patients reported at least one fall during a time period of 12 months. Fall-related injuries were common and their frequency increased with that of falls. The presence of nonataxia symptoms was associated with a higher fall frequency. This study confirms that falls are a frequent and serious complication of SCA, and that the presence of nonataxia symptoms is an important etiological factor in its occurrence.

Balance impairment is a principal symptom of cerebellar disease, but is poorly understood partly because subjects with heterogenous cerebellar and extracerebellar lesions have often been studied. Spinocerebellar ataxia type 6 (SCA6) provides an opportunity to understand balance dysfunction associated with a relatively homogenous cerebellar lesion. This study investigated stance instability in SCA6 and how it is affected by varying stance width. Body sway, as well as its directional preponderance and distribution across joints, was measured three-dimensionally in 17 SCA6 and 17 matched healthy control subjects. Subjects stood for 40 seconds on a stable surface with their eyes open and feet positioned at various stance widths (32, 16, 8, 4, and 0 cm). SCA6 subjects swayed faster than controls at every stance width. Decreasing the stance width produced a disproportionate increase in sway speed in SCA6 subjects, compared to controls. Directional preponderance of sway was dependent on stance width, but did not differ between groups. Joint instability was increased by reducing stance width in both groups, but there was greater instability of the ankle joint in the roll plane in the SCA6 group. Measures of global instability correlated strongly with disease severity measured with the Scale for the Assessment and Rating of Ataxia (r = 0.79). The sway characteristics suggest a disruption of sensorimotor processing for balance control in SCA6. The correlation with disease severity implies that balance impairment is a feature of progression of SCA6 clinical syndrome. With stance width standardized, the instability measures employed could provide sensitive, continuous outcome measures of longitudinal or therapeutic change.

Superficial cooling significantly reduced walking speed for people with HSSP. Temperature changes were associated with changes in neuromuscular impairments for both people with spastic paraparesis and controls. This study does not support the use of localised cooling in rehabilitation for people with spastic paraparesis as reported in other neurological conditions. Rehabilitation interventions that help prevent heat loss (insulation) or improve limb temperature via passive or active means, particularly when the legs and/or environment are cool, may benefit people with spastic paraparesis.