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Page 2 of 9 Elhage et al. Plast Aesthet Res 2020;7:16 I http://dx.doi.org/10.20517/2347-9264.2020.03

Despite advances in mesh technology, refinement of surgical techniques, and the advent of myofascial
reconstruction techniques, abdominal wall reconstruction (AWR) in these patients is still associated with
[4-6]
high rates of recurrence . In addition, each failed attempt at hernia repair results in higher morbidity,
[7,8]
costs, and risk of recurrence for each subsequent repair .
An especially challenging patient population for hernia specialists is those with loss of domain. This
occurs when an abdominal wall defect progresses to a size at which it may no longer accommodate the
abdominal viscera, leading to irreducible protrusion into the hernia sac. Chronic muscle retraction reduces
the volume of the peritoneal cavity and precludes tension-free fascial closure during AWR, with potential
problems such as abdominal compartment syndrome, ventilatory restriction, and an elevated risk of hernia
recurrence. In hernia defects over 8.3 cm in width, component separation is often needed to achieve
[9]
primary, tension-free fascial closure . Other techniques that have been utilized to increase the abdominal
domain in large hernias with loss of domain include progressive pneumoperitoneum and soft tissue
expanders. These are not without risk of morbidity however [10,11] .

More recently, preoperative injection of botulinum toxin A (BTA) has been added to the surgeon’s
armamentarium for AWR as an off-label use. BTA is a neurotoxin produced by the bacterium Clostridium
botulinum, which has been shown to have a variety of therapeutic uses through its inhibitory effect
[12]
on presynaptic cholinergic nerve terminals . Treatment of a muscle with BTA results in functional
denervation within 2 days and with peak effect after 4-6 weeks, leading to flaccid paralysis. This has been
successfully used for several ocular and facial nerve disorders, as well as a range of other neuromuscular
[12]
disorders including laryngeal, cervical and hand dystonia . The first experimental study reporting the
[13]
benefits of BT and its application in abdominal wall repair was published by Cakmak et al. In a rat study,
they demonstrated increased abdominal wall laxity after BTA injection in the lateral abdominal wall. The
amount of intraperitoneal saline required to reach a fixed intraabdominal pressure after BTA administration
was significantly higher than before treatment with BTA. The neurotoxin BTA results in a form of chemical
component separation, causing relaxation of the lateral muscles of the abdominal wall. The first report of
[14]
preoperative injection of BTA for AWR was by Ibarra-Hurtado et al. in 2009, where BTA was used to
facilitate fascial closure in 12 patients. The lateral muscle paralysis achieved, and transverse hernia defect
reduction in size, allowed for closure with minimal tension. BTA might also decrease pain after AWR and
the need for narcotic analgesia. Besides blocking the release of acetylcholine, BTA also prevents release
of the pain-modulating molecules calcitonin gene-related peptide and substance P from the presynaptic
[15]
motor nerve terminal .

The following review aims to summarize the literature regarding the clinical use of BTA in AWR, and assess
the varying regimens, published effects, outcomes, and complications reported.

METHODS
A literature review was performed using the PubMed Medline database. The following search and keyword
techniques were used: [(“botulinum”) AND (“hernia”) NOT (“paraesophageal” OR “esophageal” OR “hiatal”
OR “diaphragmatic” OR “disk”)]. We limited our review to studies written in English.

Our search yielded 47 articles, and 10 met our inclusion criteria for review [14,16-24] . Two independent
reviewers assessed the articles for inclusion. Studies that did not report outcomes of preoperative BTA use
in AWR for ventral hernia were excluded. We also excluded review articles, case reports, cadaveric studies,
and studies on groin hernias.

Two BTA products were utilized in the 10 studies included for analysis - onabotulinum toxin A (Botox®,
Allergan, Dublin, Ireland) and abobotulinum toxin A (Dysport®, Ipsen, Boulogne-Billancourt, France).