"On" freezing in Parkinson's disease: Resistance to visual cue walking devices

• Published in: Movement disorders Vol. 15; no. 2; pp. 309 - 312
• Main Authors: Kompoliti, Katie, Goetz, Christopher G., Leurgans, Sue, Morrissey, Mary, Siegel, Irwin M.
• Format: Journal Article
• Language: English
• Published: New York John Wiley & Sons, Inc 01.03.2000; Wiley
• Subjects: Aged; Biological and medical sciences; Cues; Diseases of the nervous system; Female; Freezing; Gait; Humans; Male; Medical sciences; Middle Aged; Muscle Rigidity - diagnosis; Muscle Rigidity - rehabilitation; Neurologic Examination; Parkinson Disease - diagnosis; Parkinson Disease - rehabilitation; Parkinson's disease; Radiotherapy. Instrumental treatment. Physiotherapy. Reeducation. Rehabilitation, orthophony, crenotherapy. Diet therapy and various other treatments (general aspects); Sensory Aids; Visual cues; Walking; Walking devices; Human; Nervous system diseases; Blocking; Parkinson disease; Cerebral disorder; Therapeutic assistance; Walking; Treatment; Laser beam; Visual cue; Central nervous system disease; Starting; Body movement; Degenerative disease; Extrapyramidal syndrome; On effect
• ISSN: 0885-3185; 1531-8257
• DOI: 10.1002/1531-8257(200003)15:2<309::AID-MDS1016>3.0.CO;2-P

OBJECTIVE To measure “on” freezing during unassisted walking (UW) and test if two devices, a modified inverted stick (MIS) and a visual laser beam stick (LBS) improved walking speed and number of “on” freezing episodes in patients with Parkinson's disease (PD). BACKGROUND Multiple visual cues can overcome “off” freezing episodes and can be useful in improving gait function in parkinsonian patients. These devices have not been specifically tested in “on” freezing, which is unresponsive to pharmacologic manipulations. METHODS Patients with PD, motor fluctuations and freezing while “on,” attempted walking on a 60‐ft track with each of three walking conditions in a randomized order: UW, MIS, and LBS. Total time to complete a trial, number of freezes, and the ratio of walking time to the number of freezes were compared using Friedman's test. RESULTS Twenty‐eight patients with PD, mean age 67.81 years (standard deviation [SD] 7.54), mean disease duration 13.04 years (SD 7.49), and mean motor Unified Parkinson's Disease Rating Scale score “on” 32.59 (SD 10.93), participated in the study. There was a statistically significant correlation of time needed to complete a trial and number of freezes for all three conditions (Spearman correlations: UW 0.973, LBS 0.0.930, and MIS 0.842). The median number of freezes, median time to walk in each condition, and median walking time per freeze were not significantly different in pairwise comparisons of the three conditions (Friedman's test). Of the 28 subjects, six showed improvement with the MIS and six with the LBS in at least one outcome measure. CONCLUSION Assisting devices, specifically based on visual cues, are not consistently beneficial in overcoming “on” freezing in most patients with PD. Because this is an otherwise untreatable clinical problem and because occasional subjects do respond, cautious trials of such devices under the supervision of a health professional should be conducted to identify those patients who might benefit from their long‐term use.