title: Relationship between freezing of gait (FOG) and other features of Parkinson's: FOG is not correlated with bradykinesia.
abstract: BACKGROUND
  The pathophysiology of freezing of gait (FOG) is unclear.
  
  
  OBJECTIVE
  To assess the relationships between FOG and other parkinsonian features in Parkinson's disease (PD), focusing on levodopa effects.
  
  
  METHODS
  Nineteen PD patients with significant FOG in "off" were assessed while "off" and "on". Three observers independently viewed videotapes of a 130-m walk and scored FOG frequency. The Unified Parkinson's disease Rating Scale was used to evaluate clinical state.
  
  
  RESULTS
  FOG frequency was not correlated with other parkinsonian features in "off" and only with speech and writing in "on". Levodopa significantly decreased FOG frequency (p<0.001). This reduction was strongly correlated with improvement of tremor (R=0.80, p<0.01) and speech (R=0.62, p<0.05), but not with improvement in rigidity, bradykinesia, or balance.
  
  
  CONCLUSIONS
  Levodopa decreases FOG in PD. FOG is apparently an independent motor symptom, caused by a paroxysmal pathology that is different from that responsible for bradykinesia, rigidity or postural instability.
authors.affiliation: Department of Neurology, Tel-Aviv University, Tel-Aviv, Israel.
authors.forename: A L
authors.initials: AL
authors.lastname: Bartels
authors.forename: Y
authors.initials: Y
authors.lastname: Balash
authors.forename: T
authors.initials: T
authors.lastname: Gurevich
authors.forename: J D
authors.initials: JD
authors.lastname: Schaafsma
authors.forename: J M
authors.initials: JM
authors.lastname: Hausdorff
authors.forename: N
authors.initials: N
authors.lastname: Giladi
mesh_terms: D000978:Antiparkinson Agents / Q000627:therapeutic use*; D020234:Gait Ataxia / Q000188:drug therapy / Q000209:etiology* / Q000503:physiopathology; D020233:Gait Disorders, Neurologic / Q000188:drug therapy / Q000209:etiology* / Q000503:physiopathology; D006801:Humans; D018476:Hypokinesia / Q000188:drug therapy / Q000209:etiology*; D007980:Levodopa / Q000627:therapeutic use*; D009043:Motor Activity; D009069:Movement Disorders / Q000188:drug therapy / Q000209:etiology; D010300:Parkinson Disease / Q000150:complications* / Q000188:drug therapy; D004856:Postural Balance / Q000502:physiology; D013064:Speech Disorders / Q000209:etiology; D014202:Tremor / Q000209:etiology
chemical_list: D000978:Antiparkinson Agents; D007980:Levodopa