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Page 4 of 20 Siegal et al. Plast Aesthet Res 2019;6:25 I http://dx.doi.org/10.20517/2347-9264.2019.35

direction, 90 degrees to the fibers of the rectus abdominis muscle. Inferiorly, it originates from the anterior
aspect of the iliac crest and lateral third of the inguinal ligament. Below the arcuate line, the TA inserts
into the pubic crest and pectineal line to form the conjoined tendon with contributions from the IO. In the
upper third of the abdominal cavity, the TA muscle inserts onto the costal cartilages of the 7th-12th ribs as
well as the xiphoid process. In this area, it extends medially beyond the semilunar line and lateral edge of
rectus abdominis (RA). Cephalad, the TA fibers interdigitate with the diaphragm muscle as well. As the TA
muscle moves caudally, its medial border moves obliquely and laterally. At the level of the arcuate line, TA
muscle fibers may no longer be visible; rather, only the aponeurosis is noticed.

The TA and internal oblique muscles are key contributors to intra-abdominal tone throughout the
thoracolumbar space. Mobilization of the TA off the underlying fascia removes its contribution to the
lateral abdominal wall leaving the IO’s contribution intact. This allows for expansion of the abdominal
cavity and thus myofascial advancement to the midline of both the lateral and medial components of the
[9]
abdominal wall, up to 8-12 cm per side in studies performed by Novitsky et al. . Additionally, TAR allows
for extensive lateral dissection for herniorrhaphy of large, recurrent, off-midline defects as well as those
that approach bony landmarks.

OPERATIVE TECHNIQUE
Patient position
The patient should be placed supine on the operating table with arms extended. The field should be
prepped from the nipple line superiorly to the mid-thigh inferiorly and to the table edge laterally. This wide
prep allows for wide mesh fixation points, if needed. Some surgeons routinely place an iodine impregnated
drape over the field to protect the mesh prosthesis from contact with any skin flora.

Entering the abdominal cavity
The surgeon should take note of previous scars; we routinely mark all prior surgical incisions prior to
placing the iodine-impregnated dressing. Poorly healed midline scars or ulcerated skin may be excised
with an elliptical midline incision for cosmetic effect. A generous midline incision is made from above to
below the hernia defect. We base the location for initial abdominal entry based on physical examination
(ideally in a location not previously violated) and on CT scan review (ideally in an area where there is clear
omental or pre-peritoneal fat present separating the fascia from the viscera). For hernias where the sac
closely approaches the skin, care should be taken when entering the hernia sac, as viscera may be shallow
to the incision. Once inside the abdominal cavity, we focus next on completing the midline laparotomy
before addressing adhesions that may be found laterally. However, generous lysis of adhesions should be
completed to free the undersurface of the posterior abdominal wall layers to allow medial advancement
and free any attachments that could lead to internal hernias. Once completed, a countable, radiopaque
towel is placed over the viscera to protect them during subsequent dissection.

Entering the retrorectus space
The medial edge of the rectus muscle should be palpated as the hernia sac or a diastasis of the recti can
cause lateralization of the muscle. Using a finger-pinch technique, the rectus can be palpated and a Kocher
clamp placed on the fascia at the anterior medial edge of the muscle. The posterior rectus sheath is then
incised 5-10 mm lateral to the medial edge. The muscle fibers must be visible to ensure that entry into the
retrorectus space (rather than transection of the linea alba) [Figure 1]. With few exceptions (notably prior
PCS), this plane should easily open and reveal loose alveolar tissue. Electrocautery is then used to extend
the incision on the posterior sheath superiorly and inferiorly. It is important to keep this incision close to
the medial edge of the muscle and not skive laterally, to preserve as much posterior sheath as possible for
reapproximation. As the incision is extended, we place more clamps (Kocher or Lahey) on both the anterior
sheath (linea alba) and the now liberated posterior sheath. The more clamps on the fascia, the more the