Abstract
Botulinum toxin (BT) is a safe and effective neuromuscular blocking agent that is clinically utilized to reduce spasticity after stroke. It is often injected repeatedly at a minimum of 12-week intervals. BT targets the neuromuscular junction and chemically denervates muscle fibers from their corresponding spinal motoneurons (MN). We explored the effect of BT on the amplitude of the smallest tendon tap force (i.e. force threshold) required to elicit a detectable biceps brachii surface electromyogram (sEMG) reflex response. We hypothesized that after BT injection, the force threshold would increase due to a decrease in available efferent activation. Two chronic stroke survivors were recruited. Data were collected before and up to 18 weeks after BT injection. For each subject, sEMG responses were analyzed using high-density sEMG (HDsEMG) recordings, and the threshold tapping forces were identified and mapped for all channels. Unexpectedly, median threshold forces (MTF) decreased post-BT (B01: 30%, B02: 50%). However, after the initial decrease, MTF then increased progressively compared to pre-BT and peaked around 12 weeks (B01: ~4 folds, B02: 50%). This is likely because post-BT, fewer available muscle fibers would require larger tapping forces to evoke detectable sEMG responses. In the last recording session (> 12 weeks), MTF did not return to pre-BT levels, indicating that successive botulinum toxin injections may still be effective if spaced much further apart in time.
| Original language | English (US) |
|---|---|
| Title of host publication | 9th International IEEE EMBS Conference on Neural Engineering, NER 2019 |
| Publisher | IEEE Computer Society |
| Pages | 385-388 |
| Number of pages | 4 |
| ISBN (Electronic) | 9781538679210 |
| DOIs | |
| State | Published - May 16 2019 |
| Event | 9th International IEEE EMBS Conference on Neural Engineering, NER 2019 - San Francisco, United States Duration: Mar 20 2019 → Mar 23 2019 |
Publication series
| Name | International IEEE/EMBS Conference on Neural Engineering, NER |
|---|---|
| Volume | 2019-March |
| ISSN (Print) | 1948-3546 |
| ISSN (Electronic) | 1948-3554 |
Conference
| Conference | 9th International IEEE EMBS Conference on Neural Engineering, NER 2019 |
|---|---|
| Country | United States |
| City | San Francisco |
| Period | 3/20/19 → 3/23/19 |
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Keywords
- botulinum toxin
- grid electrodes
- spasticity
- stretch reflex
- stroke
- surface EMG
- tendon tap
ASJC Scopus subject areas
- Artificial Intelligence
- Mechanical Engineering
Cite this
}
Variations of Tendon Tap Force Threshold needed to Evoke Surface Electromyogram Responses after Botulinum Toxin Injection in Chronic Stroke Survivors. / Afsharipour, Babak; Li, Guijin; Chandra, Sourav; Rymer, William Z; Suresh, Nina l.
9th International IEEE EMBS Conference on Neural Engineering, NER 2019. IEEE Computer Society, 2019. p. 385-388 8717098 (International IEEE/EMBS Conference on Neural Engineering, NER; Vol. 2019-March).Research output: Chapter in Book/Report/Conference proceeding › Conference contribution
TY - GEN
T1 - Variations of Tendon Tap Force Threshold needed to Evoke Surface Electromyogram Responses after Botulinum Toxin Injection in Chronic Stroke Survivors
AU - Afsharipour, Babak
AU - Li, Guijin
AU - Chandra, Sourav
AU - Rymer, William Z
AU - Suresh, Nina l
PY - 2019/5/16
Y1 - 2019/5/16
N2 - Botulinum toxin (BT) is a safe and effective neuromuscular blocking agent that is clinically utilized to reduce spasticity after stroke. It is often injected repeatedly at a minimum of 12-week intervals. BT targets the neuromuscular junction and chemically denervates muscle fibers from their corresponding spinal motoneurons (MN). We explored the effect of BT on the amplitude of the smallest tendon tap force (i.e. force threshold) required to elicit a detectable biceps brachii surface electromyogram (sEMG) reflex response. We hypothesized that after BT injection, the force threshold would increase due to a decrease in available efferent activation. Two chronic stroke survivors were recruited. Data were collected before and up to 18 weeks after BT injection. For each subject, sEMG responses were analyzed using high-density sEMG (HDsEMG) recordings, and the threshold tapping forces were identified and mapped for all channels. Unexpectedly, median threshold forces (MTF) decreased post-BT (B01: 30%, B02: 50%). However, after the initial decrease, MTF then increased progressively compared to pre-BT and peaked around 12 weeks (B01: ~4 folds, B02: 50%). This is likely because post-BT, fewer available muscle fibers would require larger tapping forces to evoke detectable sEMG responses. In the last recording session (> 12 weeks), MTF did not return to pre-BT levels, indicating that successive botulinum toxin injections may still be effective if spaced much further apart in time.
AB - Botulinum toxin (BT) is a safe and effective neuromuscular blocking agent that is clinically utilized to reduce spasticity after stroke. It is often injected repeatedly at a minimum of 12-week intervals. BT targets the neuromuscular junction and chemically denervates muscle fibers from their corresponding spinal motoneurons (MN). We explored the effect of BT on the amplitude of the smallest tendon tap force (i.e. force threshold) required to elicit a detectable biceps brachii surface electromyogram (sEMG) reflex response. We hypothesized that after BT injection, the force threshold would increase due to a decrease in available efferent activation. Two chronic stroke survivors were recruited. Data were collected before and up to 18 weeks after BT injection. For each subject, sEMG responses were analyzed using high-density sEMG (HDsEMG) recordings, and the threshold tapping forces were identified and mapped for all channels. Unexpectedly, median threshold forces (MTF) decreased post-BT (B01: 30%, B02: 50%). However, after the initial decrease, MTF then increased progressively compared to pre-BT and peaked around 12 weeks (B01: ~4 folds, B02: 50%). This is likely because post-BT, fewer available muscle fibers would require larger tapping forces to evoke detectable sEMG responses. In the last recording session (> 12 weeks), MTF did not return to pre-BT levels, indicating that successive botulinum toxin injections may still be effective if spaced much further apart in time.
KW - botulinum toxin
KW - grid electrodes
KW - spasticity
KW - stretch reflex
KW - stroke
KW - surface EMG
KW - tendon tap
UR - http://www.scopus.com/inward/record.url?scp=85066755199&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85066755199&partnerID=8YFLogxK
U2 - 10.1109/NER.2019.8717098
DO - 10.1109/NER.2019.8717098
M3 - Conference contribution
T3 - International IEEE/EMBS Conference on Neural Engineering, NER
SP - 385
EP - 388
BT - 9th International IEEE EMBS Conference on Neural Engineering, NER 2019
PB - IEEE Computer Society
ER -