Imaging of 3D Innervation Zone Distribution in Spastic Muscles From High-density Surface EMG Recordings
Spasticity
About this trial
This is an interventional treatment trial for Spasticity focused on measuring stroke
Eligibility Criteria
Inclusion Criteria:
- a history of not more than one stroke which occurred at least 6 months prior to study enrollment;
- elbow flexor spasticity rated at 2 or 3 on Modified Ashworth scale (MAS);
- receiving repeated botulinum toxin injection every 3-4 months;
- absence of excessive pain in the paretic upper limb;
- capacity to provide informed consent, with Mini-Mental State Examination (MMSE) must be 25 or higher;
The following modified Ashworth scale (MAS) will be used for spasticity assessment:
0 -No increase in muscle tone; 1 -Slight increase in muscle tone, manifested by a catch and release or by minimal resistance at the end of the range of motion when the affected part(s) is moved in flexion or extension; 1+ -Slight increase in muscle tone, manifested by a catch, followed by minimal resistance throughout the remainder (less than half) of the ROM; 2 -More marked increase in muscle tone through most of the ROM, but affected part(s) easily moved; 3 -Considerable increase in muscle tone, passive movement difficult; 4 -Affected part(s) rigid in flexion or extension.
Exclusion Criteria:
- recent botulinum toxin injection < 4 months;
- recent changes in antispastic medications <3 weeks (i.e., the antispastic medication regime is not stable;
- Changes in antispastic medications (such as baclofen, tizanidine, dantrolene etc) during the followup research visits. (NOTE: it is clinically rare for patients who receive repeated injections to change their antispastic medications);
- history of spinal cord injury or traumatic brain damage;
- history of serious medical illness such as cardiovascular or pulmonary complications;
- any condition that, in the judgment of a physician, would prevent the person from participating.
Sites / Locations
- The University of Texas Health Science Center at Houston
Arms of the Study
Arm 1
Arm 2
Active Comparator
Experimental
Standard BTX injection (ultrasound guided)
3-dimensional innervation zone (3DIZ) guided injection
For standard injection procedures, target muscles will be visualized under ultrasound imaging which is operated by an experienced and dedicated technician. Position of needle tip within the target muscle is visualized prior to injection. Ultrasound guidance can help ensure depth of needle tip location, i.e., to make sure the needle tip is within the muscle, but it is not able to tell where it is located with reference to the IZs of the entire muscle.
In the IZ-guided injection technique, IZ location obtained using the 3DIZ will be first marked over the skin surface of the muscle and the depth of the IZ will be also provided. The 3DIZ will be applied to the IZ-guided injection group 1 day prior to scheduled injection. The surface location and depth information of the IZ will be used to guide where the needle tip needs to go. Currently, patients commonly receive 1 to 2 injection sites, occasionally 3 sites for biceps muscles. To standardize the procedure, we will choose 2 sites for all patients.