| The following donor area closure protocol
is recommended by Gerard Seery.* This method is based on the principle of "deep
plane fixation" and is believed to be particularly useful in secondary or
tertiary harvesting in a fibrotic donor area or when a notably wide strip e.g. 2
cm is being taken.
The donor area strip is removed and hemostasis secured
A sewing edge is obtained with a sweeping movement of a #10 blade through the
subcutaneous tissue on both sides of the wound. This is rarely accompanied by
significant bleeding. In first time harvesting, or even in secondary harvesting
when the tissues are mobile and well vascularized, this step alone usually
allows for a simple one or two layer closure as preferred. If, however, the
wound remains refractory to closure, proceed to step 3.
Further undermine the wound edges, but not for more than another 1 cm or so
than detailed in Step 2. Evert the superior wound edge and place a PDS 2/0
suture in the deep dermis as far away as possible from the wound margin, for
example, 6-7 mm from the wound margin. Suture this as inferiorly as possible to
the deep fascia (not to the deep dermis) in the bed of the most inferior part of
the wound. Use moderate tension only (Fig. #19).
It is stressed that sutures are placed from deep dermis to deep fascia and
not from dermis to dermis. Several sutures may be necessary depending on the
length of the wound and degree of difficulty in closing. Alternate each suture
placement, that is, from as superior as possible in the dermis of the
superior flap to as inferior as possible in the deep fascia in the
inferior-most reaches of the wound and the adjacent suture from as inferior as
possible in the dermis of the inferior flap to as superior as possible in
deep fascia in the superior part of the wound (Fig. # -20). Alternate from
superior to inferior and from inferior to superior until the wound edges are
approximated. All knots are should be buried. The skin is closed with 3/0 or 4/0
nylon placed either as running or interrupted sutures.
The above is not a simple technique and requires practice to perfect. Because
of its complexity, it is an excellent five-finger exercise for improving
surgical skills. Its main benefit, however, is to facilitate low-tension
closures in fibrotic donor areas or when a wide strip is being taken and in
situations in which the surgeon is experiencing difficulty closing the wound for
whatever reasons. Its rationale is based on surgically minimizing wound tension
and thereby obviating embarking on tension-inducing methodologies in order to
effect closure.
Seery has also provided a biomechanical rationale for deep plane fixation
closure,* and it is quoted here:
"Tension created at the wound on closure is responsible for multiple adverse
sequelae (see below). The standard method of combating tension is to attempt to
overcome it with a combination of extensive undermining and traction with
tension clamps, big needles, heavy suture and muscular force. The methodology of
donor site closure, detailed above, is a modification of deep plan fixation.
This eschews extensive undermining and traction closure. The rationale for its
use depends on two tenets of surgical practice:
- Channeling tension forces through non-undermined tissues notably limits
their adverse effects as compared with tension transmitted in extensively
undermined tissues * and
- tension vector forces channeled away from superficial "at-risk" tissue into
deep plane tissues allows the adverse effects of tension to be dissipated in
tissues other than the wound.*
The most important criterion in deciding the width of the strip that may be
successfully harvested, without creating undue tension at closure, is the laxity
of the tissues.* Donor area tissues may be either naturally tight or tight as a
result of prior harvesting. A combination of each is the worst possible
scenario. The belief that closure problems posed by tight scalps can be solved
by extensive undermining and stretching is in serious need of review. The scalp
is made up of collagen, elastic fibers, blood and lymphatic vessels, and nerve
fibers with mucopolysaccharide ground substance and tissue fluid. All of these
elements are adversely affected by extensive undermining and stretching. The
ability of skin to recover from stretch resides in its elastic component. When
skin stretches, the elastic fibers elongate in the direction of the stretching
force, allowing the convolutions in collagen to straighten out. The resultant
elongation is a function of progressive displacement of ground substance and
tissue fluid, which accompanies collagen realignment.* This continues until
there is a structure of parallel collagen fibers that resists further extension.
This complies with a principle of Physics that states that stress (stretch) is
directly proportional to strain (elongation) provided the elastic limit is not
exceeded. The elastic limit of skin (or any substance) is that point at which
the components commence to rupture and the stress/strain ratios no longer apply.
It is accompanied by adverse tissue changes. The elastic limit for skin elastin
is about 100% and that for collagen 10%. When skin elongates more than 100% of
its resting length, the elastic fibers rupture.* The impaired elastic is now no
longer able to return the collagen to its normal resting state even when stress
is removed. This results in permanent, irremediable adverse consequences for the
tissues called plasticization, better known to surgeons as stretch-atrophy.
(thin, dry, brittle, poorly vascularized skin) commonly seen following donor
area traction closures and after overly ambitious alopecia reductions.*
Stretch-atrophied tissues are relatively unsatisfactory for subsequent
harvesting or hair transplantation.* Skin stretching also attenuates blood
vessels decreasing tissue perfusion which, if allowed to continue unchecked,
will ultimately exceed the critical closing pressure and perfusion stops. Lesser
degrees of stretch will reduce circulation. Elongation of nerves and reduced
lymphatic drainage causes pain and edema, respectively.*
Non-undermined skin is better able to withstand the ill effects of tension
stretching than undermined skin. Extensive undermining is also ineffectual. In a
clinical research study by Seery, * two groupings of mid-line alopecia
reductions were described, the only difference being that one had undermining of
15 cm bilaterally and the other only 5 cm of undermining bilaterally. The
excision widths in each group were identical at 39 mm. There was no significant
difference in stretch-back. The suggested the extra undermining of 10 cm
bilaterally contributed nothing in terms of increased tissue excision. This
conclusion is scientifically supported by Raposio * who, in an excellent paper
on tensiometric measurements in serial scalp reduction, reported "the benefits
of an extensive (15 cm) undermining were minimal as compared with those obtained
with 5 cm undermining." As a practical matter, it is unlikely that undermining
of much more than 2.5 cm from the donor wound edge is worthwhile."
Figure 13 The graph of
straight, curly, and kinky hair.
Table 8. Percentage of
naturally occurring surface hair groups per follicular cluster based on regional
location in the individuals, who are a Norwood Class III-VI.60
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