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Page 4 of 11 Shaw et al. Plast Aesthet Res 2021;8:52 https://dx.doi.org/10.20517/2347-9264.2021.53

Penile skin flaps
Penile skin flaps can provide single-stage reconstruction, even in long-segment anterior urethral stricture
disease. Penile skin, particularly distal or preputial skin, in the appropriately selected patient will meet the
four primary factors for an ideal flap. These flaps share a common blood supply from the external pudendal
artery and involve the isolation of a skin island that is mobilized for urethral reconstruction. Penile flaps are
best characterized by the location/orientation of the harvested skin island, the pedicle origin, and the way in
which the flap is incorporated into the urethra . Flap techniques have also acquired the eponym of the
[17]
surgeon who first described that technique. Details and success rates of penile skin flaps are discussed below
and are summarized in Table 1.

Penile anatomy
Appropriate utilization of penile skin flaps depends on an understanding of the penile blood supply. The
cross-sectional anatomy of the penis is shown in Figure 1. Penile skin flaps depend on the subcutaneous
plexus traveling in the tunica dartos just superficial to Buck’s fascia. This plexus is derived from axial penile
arteries, which arise from the superficial and deep branches of the external pudendal artery [Figure 2].

Types of penile skin flaps
Penile skin flaps are described by anatomic classification. As described by Elliott and McAninch , this
[17]
classification should define the orientation of the harvested flap (longitudinal vs. transverse), the location
where the skin island was derived (proximal vs. distal penile skin), the vascular supply (dorsal vs.
ventrolateral pedicle), and how the flap is incorporated into the urethra (onlay vs. tube vs. combined tissue
transfer). In addition to the anatomic description, the flap is also often described in the literature based on
the eponym of the describing surgeon. For example, the longitudinal ventral penile skin flap with lateral
pedicle placed as a ventral onlay is also referred to as the “Technique of Orandi” or “Orandi Flap” [27,28] .
Further confusion can arise with modifications of classic descriptions, such as a tubularized “modified
Orandi Flap” . It is therefore important to adhere to the anatomic description described above.
[29]

Longitudinal ventral penile skin flap with lateral pedicle (Orandi flap) [28]

With the penis on stretch, a vertical, ventral penile shaft incision is made over the strictured area that
corresponds to the approximate stricture length [Figure 3]. This incision should be carried lateral to the
corpus spongiosum and will be the deep incision for flap harvest. On the contralateral side, a lateral
urethrotomy is made until there is normal urethral mucosa is encountered at the proximal and distal aspects
of the urethrotomy. A skin island is then dissected to match the urethrotomy defect. The superficial incision
is then made and carried laterally to release the skin island and allow for suturing of the flap to the
urethrotomy in a tension-free anastomosis [Figure 4].

Longitudinal ventral penile skin flap with ventral pedicle (Turner-Warwick flap) [30]

Similar to the Orandi technique, this is a skin island flap derived from ventral skin. The Turner-
[28]
[30]
Warwick differs in that the pedicle is derived from bilateral ventrolateral arteries and used mostly in the
bulbar urethra. Often the skin marking is made after perineal dissection and characterization of the bulbar
urethral stricture. The deep plane of the skin island is developed distally, and the superficial layer is
developed at the proximal flap apex. The island and pedicle are then raised and inverted through the scrotal
tunnel and out the separate perineal incision to be incorporated into the bulbar urethra [Figure 5]. This
technique has been described most in modern literature as part of augmented anastomotic urethroplasty.