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mds21716-MDS21716.mpg13394KSegment 1. This shows that the patient could walk normally with eyes open. Tandem gait performance was unremarkable. However, the pull test was very abnormal, and with each shoulder pull the patient fell backwards in the hands of the examiner, without making any attempts to correct.Segment 2. This shows the Romberg test. Immediately after eye closure, the patient fell backwards like a log into the hands of the two examiners, again without any attempts to prevent a fall.Segment 3. In this we asked the patient to walk with eyes closed, and this produced an unexpected effect. Shortly following eye closure, the patient began to gradually lean backwards, requiring help from two assistants to prevent her from falling. However, despite this backward inclination, she continued to make stepping movements, and this continued even when she was lying on her back on the floor. The recumbent walking movements continued until we asked the patient to open her eyes, at which point she reported finding herself unexpectedly lying on the ground. This abnormal gait pattern was repeatedly seen, first several times when she was initially seen in the outpatient clinic, and again several days later when she returned to our clinic to videotape her gait disorder.

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