LETTER TO THE EDITOR
Improving the reliability of the Keystone flap
Received: 8 February 2015 /Accepted: 14 April 2015 /Published online: 6 May 2015
Springer-Verlag Berlin Heidelberg 2015
The defects after lower limb skin cancer excision espe-
cially in the elderly patient cannot often close directly
due to unfavourable tissue factors such as poor skin
quality, inelastic skin, and peripheral oedema. Tradition-
ally, skin grafting is performed with variable success;
failure occurs for many reasons including graft shear,
haematoma, wound oedema, and infection . Post-op-
eratively, a successful graft and donor site require reg-
ular follow-up and after-care whilst any complications
increase this requirement.
The Keystone design perforator island flap is a relatively
recent surgical option for these sites . Behan’s original de-
scription of the Keystone flap states that a one-to-one ratio of
defect to flap is suitable . However, closure using the one-
to-one ratio of defect to flap width is normally tight and can
sometimes be challenging to close, therefore necessitating
Bback grafting^ of the donor defect or the addition of a further
Keystone flap opposite the first flap to make a type III repair.
These lengthen the operation and increase its’ morbidity. Au-
thors have also outlined a modification of the Keystone flap
with a V–Yapposition centrally to improve the ability to close
the defect .
We have found that at least doubling the flap to defect ratio
has eliminated any need for back grafting and allowed direct
closure on limbs with friable inelastic skin (Fig. 1). This is
quicker than converting a type I or type IIa flap to the type III
variant and allows for a much more robust flap.
Behan’s suture protocol using a few interrupted non-
resorbable mattress tensioning sutures and a continuous run-
ning non-resorbable horizontal mattress suture to hem the
wound works well but requires staged removal of these stitches.
We recommend using Vicryl™ (Polyglactin 910, Ethicon,
US) rapide 3/0 or 4/0 for the tensioning and continuous hem-
ming sutures to close these larger flaps. The suture line is then
Mefix™ (Self adhesive fabric, Molnlycke health care, UK) and
then protected with gauze wool and a crêpe bandage. The
gauze wool and crêpe bandage can be removed by the patient
at 48 h, and then the wound can be washed and the tape patted
dry by the patient for the next five days before they remove it.
The patient is seen in clinic for the histology results 3 to 4 weeks
after the surgery.
Many of our patients are treated as day cases and
who can ambulate full weight bearing with this regime.
We have had excellent aesthetic outcomes and patient
* Dariush Nikkhah
Department of Plastic Surgery, Queen Victoria Hospital,
East Grinstead, UK
Eur J Plast Surg (2016) 39:237–238