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jws-mds.21000.mpg13671K The videotape shows three early-onset primary torsion dystonia patients with limb onset and slow progression. Patient 1: This patient had the GAG deletion in the DYT1 gene. He developed task-specific dystonia in the right lower limb at 9 years of age, which subsequently progressed to a generalized form. The first segment shows the patient at 11 years of age, 2 years after onset when all limbs are affected, with clumsiness of movements in the upper limbs and impaired gait, with outward rotation of the right lower limb. The second segment shows the patient at 14 years of age. Dystonia can also be observed at rest in the right lower limb; during attempted voluntary movement, there is abnormal extensor posture of leg and flexion of the right foot. Patient 2: This is a sporadic non-DYT1 patient, who presented dystonia at 6 years of age. The right upper limb was affected first. The dystonia subsequently progressed without involving the lower limbs. The first segment shows the patient 6 months after onset. Action dystonia is evident in the right upper limb, left hand movements are clumsy, but the patient walks without difficulty. Segment 2 shows the patient at age 14; he has severe upper limb, cervical, and trunk dystonia. Remarkably, the lower limbs are spared. Patient 3: Shown is a sporadic non-DYT1 patient who developed dystonia at 8 years if age. The disease started in the right upper limb and slowly spread to the contralateral upper limb, then mildly affected the trunk before stabilizing with no further progression. Segment 1 shows the patient at age 10: action dystonia of both upper limbs is obvious. Segment 2 shows the patient at age 16: severe dystonia occurs in both upper limbs and there is minimal trunk involvement.

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