Botulinum toxin type A injections temporarily paralyze the muscle, decreasing muscle spasms and contraction, and in doing so, decrease the time needed for expansion.
“The infiltration of the pectoralis major muscle with neurotoxin in immediate, expander-based reconstruction may be beneficial in reducing pain and expediting expansions,” the study authors note. The findings appear in the Aesthetic Surgery Journal.
In the study, 30 patients were randomly assigned to one of two treatment groups. The neurotoxin group received 40 units of Botulinum toxin type A into each pectoralis major muscle through four serial injections, while the placebo group received four serial injections of 0.9% NaCl.
All subjects were observed over a year. The patient demographic, visual analog score, laterality, office visits, amount of expansion, number of times to full expansion, and amount of narcotics required were recorded.
There were no significant differences between the two groups in terms of age, laterality, expander size, or complications (p=.46 to .66). There was, however, a significant difference between the two groups in the visual analog score, demonstrating decreased pain in the neurotoxin group (p<.05).There was no significant difference in narcotic use between the two groups in the first 3 days postsurgery. However, there was a significant decrease of use of narcotics for pain in days 7 to 45 in the neurotoxin group. In addition, there was a significant increase in the volume of expansion per visit in the neurotoxin group as compared to the placebo group (p<.05), the study showed.
Botulinum toxin type A has not been approved by the US Food and Drug Administration for paralysis of the pectoralis major muscle in breast reconstruction surgery, so this falls under off-label use. It isn’t the first time that investigators have reported on using Botox in the breast. Several years ago, there were many media reports on a “Botox breast lift.” This procedure involved injecting Botox into the pectoralis minor chest muscle to allow the back muscles to compensate by lifting the breast.