title: Freezing of gait in multiple system atrophy (MSA).
abstract: BACKGROUND
  Freezing of gait (FOG) is a mysterious symptom, observed in different parkinsonian syndromes, but considered to be rare in multiple system atrophy (MSA).
  
  
  OBJECTIVE
  To assess the frequency of FOG in patients with MSA.
  
  
  METHODS
  We studied the presence of FOG in 28 patients with clinical diagnosis of MSA. 21 patients had probable MSA and 7 had possible MSA. The clinical diagnosis was based on neurological examination performed by at least two experienced movement disorders specialists as well as on the results of ancillary examinations and the course of the disease. In 22 patients MSA was predominated by parkinsonism (MSA-P) and in 6 by cerebellar signs (MSA-C). The patients' mean age was 66.8+/-10.3 years, mean disease duration 6.4+/-4.0 years and mean worst Hoehn and Yahr (H&Y) stage was 3.6+/-0.6. Presence and severity of FOG was assessed during the last office visit, by the recently validated FOG questionnaire (FOG-Q), with a maximal score of 24, while patients that received at least one point in the last four questions were classified as having FOG. Severity of FOG was determined by the sum of these last four out of six questions (maximal score is 16). FOG-Q total score reflected general function and walking ability disturbances, caused by FOG. The comparison between groups of patients was performed by way of the Mann-Whitney two-sample test and chi-square or Fisher's exact tests. Correlations between various parameters were calculated using Spearman's correlation coefficient.
  
  
  RESULTS
  Twenty-one patients were able to walk and 7 were bedridden at the time of the study. FOG appeared in a total of 75% of all MSA patients (in 82% of patients with MSA-P and in 50% patients with MSA-C). In the MSA-P group disease duration was about the same among 'freezers' and 'non-freezers', while among the MSA-C patients it was significantly shorter in the non-freezers. Mean score of the freezing subdivision of the FOG-Q was 8.2+/-5.1 for MSA-P group and 4.5+/-5.1 for MSA-C one. Mean FOG-Q total score was 9.1+/-4.0 and 6.2+/-4.6 (p>0.05) for MSA-P and MSA-C patients, respectively.
  
  
  CONCLUSIONS
  Freezing of gait is a common symptom in MSA, both in MSA-P and MSA-C.
authors.affiliation: Department of Neurology, Tel-Aviv Sourasky Medical Center (Affiliated with Sackler School of Medicine), Tel-Aviv University, 6 Weizmann Street, 64239, Tel-Aviv, Israel. gurevich@tasmc.health.gov.il
authors.forename: Tanya
authors.initials: T
authors.lastname: Gurevich
authors.forename: Nir
authors.initials: N
authors.lastname: Giladi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016009:Chi-Square Distribution; D005260:Female; D020233:Gait Disorders, Neurologic / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D019578:Multiple System Atrophy / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology*; D018709:Statistics, Nonparametric