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Page 2 of 3 Egro et al. Plast Aesthet Res 2019;6:14 I http://dx.doi.org/10.20517/2347-9264.2019.30

It was interesting that conditions such as malnourishment and renal disease predispose patients to a
significantly higher incidence of skin grafting use. In malnourishment, a lack of proteins may lead to
a decrease in colloid osmotic pressure which in turn leads to diffusion of fluid in the interstitium, thus
[6]
increasing edema . Similarly in renal disease, there is urinary protein loss leading to decrease of plasma
albumin and subsequently lowering the plasma oncotic pressure leading to an imbalance of the Starling
[7]
forces . This drives fluid from the intravascular space to the interstitial space leading to fluid imbalance
and potential for fluid overload. Both of these conditions contribute to the difficulty in primary closure and
consequently skin grafting.

Skin grafting can be a significant issue when placed over a vascular pedicle. The thin and non-vascularized
nature of the graft places the pedicle at risk for dessication and injury. Skin grafting has a greater
[8]
propensity to contract at the recipient site due to the reduced volume of included dermis . This can lead to
compression of the pedicle secondary to scarring and graft contracture especially when localized around a
joint. Furthermore, the skin graft donor site carries additional morbidities such as scarring, infection and
[9]
pain , though as the authors mentions, redundant skin from the flap donor site is usually available without
increasing scar length.

The concept of using skin grafting to cover free flap pedicles should be considered a last resort when
everything else fails because of a concern of vascular injury and flap compromise. Although this study
concludes that it is safe to adopt this technique, the small sample size and underpower of the study may
make the authors conclusion premature.

The indication to employ a free flap in the first place is to obtain durable coverage of exposed critical
structures such as tendon, bone, hardware, and vessels. We include the flap pedicle in this category. We
suggest several methods to avoid skin grafting. One strategy is to make the free flap large enough to cover
the entire course of the pedicle. This technique is simple, but may have a poorer cosmetic outcome due to
the larger surface area of flap skin. Another strategy is to create an adipofascial extension to the free flap
or create a chimeric flap. The anterolateral thigh (ALT) flap is particularly amenable to this. If an ALT
does not require primary thinning, an extension of vascularized fascia plus adipose tissue can be draped
over the pedicle. If the anastomosis site is too far from the defect, a chimeric flap can be designed, either
adipofascial tissue on its own perforator, or a small segment of vastus or rectus muscle based on a branch
close to the pedicle origin. Yet another method consists of rearranging tissues adjacent to pedicle [10,11] .
Rearrangement strategies can be as simple as undermining and advancing local tissue or creating local
flaps. When the incision to dissect recipient vessels is parallel to the defect, the skin bridge can be
completely undermined and advanced as a bipedicle flap. If a local flap cannot be designed with primary
closure of the donor site, we would prefer to have vascularized skin over the pedicle with a skin graft on
the local flap donor site.

Designing a free flap that anticipates the steps required to obtain tension free closure over the pedicle can
be challenging. Local tissue trauma or edema can compromise local flap options. If skin grafting is truly
the only option, as situation we have also found ourselves in, we recommend harvesting the skin graft
from the free flap donor site as described by the authors to avoid additional scarring. If this option is not
[12]
available, a skin graft can be taken directly off the free flap to avoid the morbidity of a second donor
[13]
site . At our institution, we do not have a preference between full thickness and split-thickness skin
grafts [14,15] . The established benefits and drawbacks of take, contracture, tissue thickness, and esthetics are
weighed by the surgeon.

We are grateful to Kovar et al. for shining insight on a very interesting topic and offering data on the use
[1]
of skin grafting of the vascular pedicle. We do believe skin grafting should be used only as a last resort.