British Jmmaiof PIastic Surgery (Ml), 44.33-35 0 1991 The Trustees of British Association of Plastic Surgeons
The dartos musculocutaneous flap V. K. Tiwari, P. Kumar and R. K. Sharma Department of Burns, Plastic and Maxillofacial Surgery, Safdarjung Hospital, New Delhi, India SUMMAR Y. Six dartos musculocutaneous flaps have been used to resurface proximal penile defects. The vascular anatomy of the flap, surgical technique and complications are described in detail.
of skin island is marked over the anterior surface of the scrotum, taking care not to cross the midline (Fig. 1). An incision is made in the distal half of the circumference of the island, cutting skin, fascia and dartos muscle. In the proximal half only skin is divided. With gentle traction over the island, the skin is dissected from over the pedicle (dartos muscle and fascia). This step is facilitated by injecting saline solution between the skin and dartos muscle. Dissection stops at the base of the flap which is raised from the level of delicate, relatively avascular areolar tissue. The width of the dartos muscle pedicle equals the horizontal dimensions of the skin island. After complete haemostasis the skin island is delivered into the penile defect through a subcutaneous tunnel (or after making a skin incision). The donor defect is closed in two layers. The thin skin dissected off the pedicle may be discarded. A gentle pressure dressing is applied, avoiding pressure over the pedicle.
The resurfacing of penile defects by split thickness skin grafts poses a problem of difficult immobilisation in the immediate postoperative period and some degree of contracture is inevitable. The use of an abdominal flap avoids these problems but it is very bulky. We have devised a dartos musculocutaneous flap of scrotal skin to resurface proximal penile defects in one stage. Vascular anatomy
The scrotal skin is supplied by anterior scrotal branches of the deep external pudendal artery, posterior scrotal branches of the internal pudendal artery, the cremasteric branch from the inferior epigastric artery and branches from the testicular arteries. Veins follow these arteries and join the saphenous vein before it enters through the saphenous opening (Gray’s Anatomy, 1973). The dartos musculocutaneous flap is based on the anterior scrotal branches of the deep external pudendal artery. On the skin surface its course can be represented by a horizontal line running towards the scrotal neck from 5 cm below the origin of the femoral artery (Cormack and Lamberty, 1986). A line drawn downwards from the mid-point of the anterior surface of the scrotal neck, making an 80” angle from this horizontal line, represents the vascular axis of the flap. Its base lies on this line, 5 mm below the horizontal line (Fig. 1). Material and method
Five dartos musculocutaneous flaps have been used to resurface dorsal proximal penile defects produced as a result of the release of bum contractures. In one patient with partial amputation of the penis, who had undergone previous failed split skin grafting, the raw area was covered by bilateral dartos musculocutaneous flaps (Table 1). Fig. 1
Figure l-Marking the flap : M = mid-inguinal point ; AB = line representing course of the deep external pudendal artery; C = midpoint of anterior surface of scrotal neck; CD= vascular axis of flap; P = pedicle; S = skin island; E = base of flap.
The penile defect is measured and, after marking the vascular axis and pedicle (see above), the required size 33
Table 1 Case no.
Post-electric burn dorsal contracture penis (Fig. 2)
4 x 4.5
4 x 2.5
4.5 x 3
Size of skin island (cm)
Size ofpedicle (cm)
4.5 x 3.5
4.5 x 2.5
of penis (Fig. 3)
In the first three cases, since we did not drain the wound haematomas were noticed. In these cases one stitch was cut and the haematoma was removed. After drainage of the haematomas, two flaps healed normally (Cases 3 and 4) but in one case (Case 2) there was superficial necrosis of the distal 5 mm of the flap, which healed in 15 days by marginal epithelialisation after repeated dressings. In subsequent cases the wounds were drained to avoid haematoma formation. Mild oedema was noticed in two flaps (Cases 2 and 6), which disappeared after the 4th postoperative day. In the immediate postoperative period sensation was intact in all the cases. The result in all six cases
Haematoma, oedema and necrosis of distal 5 mm of flap
Bilateral 5x4 5x4
flaps 5x3 5x3
was satisfactory at 6-10 months follow-up, and all the flaps succeeded in their purpose. Two illustrative cases are shown in Figures 2 and 3. Discussion
The dartos musculocutaneous flap is a convenient single-stage procedure to cover proximal penile defects, with definite advantages over split skin grafting. The scrotal skin is very elastic and can be stretched to great dimensions. We have raised a 5 x 4 cm skin island from either side of the scrotum in one stage without any problem in closure of the donor area. The anterior surface of the scrotum is supplied by the ileoinguinal nerve which can be preserved during eleva-
Fig. 3 Figure 2-Case I. (A) Post-electric bum dorsal contracture of penis. (B) Immediate postoperative results; donor area has been closed primarily. (C) The healed flap. Figure 3-Case 6. (A) Diagram showing raw area over penile amputation stump. (B) Bilateral scrotal flaps have been used to resurface the defect of the penile stump. Donor areas have been closed primarily.
The Dartos Musculocutaneous Flap tion and in all our flaus sensation was intact in the postoperative period. * The only disadvantage of the flap is that it provides hairy skin-with penile area.
over the proximal
V. K. Tiwari;MS, MCh, Plastic Surgeon. Pramod Kumar. MS. MCb. DNB. Senior Resident. R. K. Sharma, MS, Postgraduate&dent
Department of Bums, Plastic and Maxillofacial Surgery, Safdajung Hospital, New Delhi, India.
References Cormack, G. C. and Lamberty, B. G. H. (1986).The Arterial Anatomy of Skin Flatx. Edinburgh, London, Melbourne, New York:
Requests for reprints to: Dr V. K. Tiwari, A-238, Moti Bagh I, New Delhi 110 021, India.
Gray’s Anatomy (1973). 35th Edition. Warwick, R. and Williams,
P. L. (Eds). London: Longmans.
Paper received 27 February 1990. Accepted 26 June 1990.