The primary goal of this clinical trial is to examine the effects of cervical vibrotactile stimulation intensity on abnormal head posture in people with cervical dystonia. The main question is: Does higher vibration intensity correct head posture to a greater extent than lower vibration intensity? Researchers will compare the head posture of participants with cervical dystonia who receive different intensities of vibration to cervical muscles. The secondary goal of this clinical trial is to examine the degree of proprioceptive impairment in cervical dystonia. Specifically, the study will assess proprioceptive impairment at the neck, wrist, and ankle joints, and seeks to determine whether the impairment improves with cervical vibrotactile stimulation. Researchers will compare the proprioception testing results of these joints between cervical dystonia patients and age- and sex- matched healthy controls. Researchers will also compare the neck proprioception testing results of cervical dystonia patients before and after stimulation. Participants will visit the lab once for three hours, where they will go through: 1. clinical questionnaires; 2. neck, wrist, and ankle proprioception testing, 3. vibrotactile stimulation where they sit and relax 4. neck proprioception testing
Study Type
INTERVENTIONAL
Allocation
NON_RANDOMIZED
Purpose
TREATMENT
Masking
NONE
Enrollment
50
The intervention in this study is vibrotactile stimulation with 3 different intensities on 4 combinations of cervical muscles. The three intensity levels are 0.25mm, 0.64mm, and 1.48mm of movement range of the vibrator, when attached to the cervical area. The four muscle combinations (left and right SCM, left and right TRP, left SCM and TRP, right SCM and TRP) are selected as they were shown to be more effective than other combinations in a previous studies. The total number of bouts of stimulation is 12 (3 intensities \* 4 muscle combinations). Each VTS application is 2 minutes long, resulting in total stimulation time of 24 minutes. There will be a 5-minute break of no-vibration between each application of vibration. During the intervention, the participant will remain seated and asked to not interfere voluntarily with dystonic muscle spasms. During breaks, they can adjust their head posture for their comfort. Extra breaks will be given if needed.
Human Sensorimotor Control Laboratory
Minneapolis, Minnesota, United States
RECRUITINGHead Angle Index
The primary outcome measure is the head angle index, which quantifies how much a participant's head posture deviates from a neutral upright position. There are three degrees of freedom for the neck joint (axial rotation, lateral bending, and flexion/extension). For each participant, the degree(s) of freedom with abnormality will be identified at baseline. For any time period during the experiment, the mean absolute neck angle in each abnormal degree of freedom will be calculated and normalized by the typical maximal range of motion in healthy individuals. These normalized values will be averaged to yield the Head Angle Index.
Time frame: As part of the one-time visit, this part will take 90 minutes.
Position Matching Error
The secondary outcome measure is absolute position matching error, which quantifies the position sense acuity of the participants in each joint. For each tested joint, they will be given a set of target position. The joint will be passively rotated to the target position, and back to the starting position. The participant will then try to reproduce the target position, based on their memory of the position. After repeating for 9 times, the absolute value of the differences between the matched position and the target position will be averaged to get the absolute position matching error.
Time frame: As part of the one-time visit, this part will take 60 minutes.
the Toronto Western Spasmodic Torticollis Rating Scale Score
This three-part rating scale will evaluate the severity, disability and pain level of each CD participant. Each part results in a numerical score.
Time frame: As part of this one-time visit, 10 minutes.
Fahn-Tolosa-Marin Clinical Rating Scale Score
Tremor severity level will be evaluated with this numerical score.
Time frame: As part of a one-time visit, 10 minutes.
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.