Category: Spasticity
Objective: Spasticity is a speed-dependent increase in muscle tone associated with stiffness, enhanced osteotendinous reflexes, paresis, loss of fine motor control, and increased fatigue. The neural insult itself causes paresis, and the consequent immobilization of the paretic part of the body can cause adaptive shortening of the muscles and joint contractures. Infiltrative treatment with botulinum toxin type A (BTX-A) is effective, safe and with few side effects . However, the efficacy of this treatment may be reduced due to changes affecting the muscle fibers in spasticity. The study aims to investigate the influence that different volumes of saline vehicle have on the efficacy of BTX-A in reducing the spasticity of the upper limbs in the fibrotic muscles analyzed by ultrasound.
Background: the efficacy of Incobotulinum toxin type A is clinically assessed by the Modified Ashworth Scale (MAS) and its score is based on the assessment of muscle resistance during passive movement. The instrumental study, on the other hand, involves the use of ENG with analysis of Compound Motor Action Potentials (cMAP) and Miometric Measurement (MYO), which provides an objective way to quantify physiological properties of muscle tone, including stiffness.
Method: 10 patients after different years of treatment with BTX-A of the brachial biceps (BB 100U) and superficial flexor of the fingers (FSD 100U), showed no clinical and instrumental efficacy. Due to this low response we increased the dilution to 4% for BB and to 3% for FSD (the dilution was proportional to the muscle size).
Results: The results obtained showed a significant tone reduction according to MAS, to BB and FSD MYO, to musculocutaneous and median nerve cMAP.
Conclusion: In fibrotic muscles, different volumes of saline vehicle improved the effect of BTX-A. The functional benefit obtained in patients is related to the evaluation of muscle changes evolved in spasticity and to the study of a treatment to prevent these changes.
To cite this abstract in AMA style:
R. Marvulli, G. Ianieri, G. Mintrone, A. Zonno, L. Rizzo, G. Farì, M. Ranieri, M. Megna. The efficacy of Botulinum toxin A in reducing muscle spasticity by different volumes of dilution [abstract]. Mov Disord. 2022; 37 (suppl 2). https://www.mdsabstracts.org/abstract/the-efficacy-of-botulinum-toxin-a-in-reducing-muscle-spasticity-by-different-volumes-of-dilution/. Accessed May 21, 2025.« Back to 2022 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/the-efficacy-of-botulinum-toxin-a-in-reducing-muscle-spasticity-by-different-volumes-of-dilution/