Free Profunda Artery Perforator Flap Breast Reconstruction

Key Words

Profunda artery perforator flap, vertical profunda artery perforator flap, transverse profunda artery perforator flap, microvascular breast reconstruction, stacked flaps, posterior thigh, vertical flap

Introduction

Breast reconstruction is a common challenge faced by many surgeons working in the plastic and reconstructive arenas. There are various options for autologous breast reconstruction. The more commonly performed procedures include the deep inferior epigastric perforator flap (DIEP) and the superior and inferior gluteal artery perforator flaps (SGAP, IGAP). Despite the refinements in the latter donor sites, specific reconstructive needs and body habitus sometimes call for an alternate donor site. This has led to the development of the medial thigh as a donor site, more specifically based on the profunda artery system.

The senior author first introduced the PAP flap for breast reconstruction at the 13th International Course on Perforator Flaps in 2010. The patient was a 52-year-old woman with previous failed attempts at breast reconstruction using implants and then a transverse rectus abdominis muscle flap. As the patient had been noted to have excess posterior thigh tissue, Dr. Allen decided to proceed with the first posterior thigh profunda artery perforator (PAP) flap for microsurgical breast reconstruction. This idea was supported by the background work of other surgeons and anatomists, who had previously described the profunda artery anatomy as responsible for the regional blood supply of the posterior upper thigh. The PAP flap had become an innovative addition to the breast reconstructive armamentarium.

The PAP flap has proven to have consistent anatomy and blood supply, with adequate perforator size for anastomosis to the internal mammary or thoracodorsal vessels. Additionally, due to its elliptical pattern used for flap design, it has proven to have excellent aesthetic results, either coned to accommodate the natural contour of the breast, or stacked to create a full-shaped breast.

The donor-site incision is concealed in the gluteal crease in the transverse pattern, or in the transition between the medial and posterior thigh in the vertical pattern. Like all of the various options for microsurgical free tissue transfer, the PAP flap is not without its disadvantages; however, the reported complication rate has overall been quite low and acceptable as compared to the alternative options for autologous tissue breast reconstruction.

In this chapter, we will focus on providing guidelines for using the PAP flap by discussing the indications and contraindications for choosing this flap for breast reconstruction, how to properly evaluate a patient who appears to be a good candidate for this procedure, our surgical technique, and the postoperative care. Additionally, we will provide some case examples of the various uses of the PAP flap, and some variations to this technique. These include the use of a transverse incision, vertical incision, and its use as stacked flap, “four flap” autologous breast reconstruction with use of DIEP flaps along with PAP flaps. Finally, we will discuss some possible complications, how to avoid them, and appropriate short- and long-term management of patients having this surgical procedure, including the need for secondary procedures for improved aesthetic outcomes.

Indications and Contraindications

Although the DIEP flap has been the workhorse for microsurgical breast reconstruction, there are some circumstances that make the PAP flap a more valuable option. Some indications that favor the use of the PAP flap include patients with previous abdominal surgery and/or thin patients with a paucity of abdominal tissue. There is also a subset of patients who do not wish to use their abdominal tissue for reconstruction, or are trying to avoid an anterior abdominal scar, thus making the PAP flap an ideal option, especially with its inconspicuous donor site scar. The PAP flap has been harvested on patients with various body mass indexes; the ideal patient has small to moderate-sized breasts and excess body fat below the waist. The PAP flap has also been used in different reconstructive scenarios such as lower extremity and head and neck reconstruction. The PAP flap has no major contraindications; however, we see a limitation in those patients who have limited hip abduction or previous surgery to the inferior gluteal crease region.

Preoperative Evaluation and Special Considerations

The PAP flap has proven to have consistent anatomy; however, preoperative imaging is paramount in surgical planning. Current imaging modalities such as computed tomography angiography (CTA) and magnetic resonance angiography (MRA) have demonstrated great utility in the identification of perforator vessels needed for flap harvesting. Saad et al. demonstrated the consistent anatomy for the PAP based on cadaveric dissection and CT scanning, which showed the perforator supplying the medial and posterior thigh skin and subcutaneous tissue just below the buttocks crease. Identification of these perforators has become the standard of care for the surgical planning of the PAP flap ( Fig. 6.1 ).

The CTA technique should be performed in a high-resolution scanner with thin cuts. With the patient in prone position, a marker should be placed in the gluteal crease, which will help provide accurate measurements relating to the perforator position for flap design. The perforators will be identified posterior to the gracilis muscle as septocutaneous or musculocutaneous perforators through the adductor magnus.

Surgical Techniques

Relevant Surgical Anatomy

The PAP flap has very consistent anatomy. The profunda femoris artery branches off the lateral aspect of the femoral artery 3.5 cm below the inguinal ligament and enters the posterior compartment of the thigh to split into medial and lateral branches before giving off its major perforators: the first perforator supplies the adductor magnus muscle, and the second and third perforators supply the semimembranosus, biceps femoris, and vastus lateralis muscles.

The numerous consistent perforators, in combination with preoperative imaging, have allowed versatility in the design of the skin flap pattern. As such, despite the common use of the transverse design, other orientations such as the vertical and diagonal designs have also been successfully used.

Preoperative Markings

Transverse Flap Design

Imaging is key in order to appropriately design the flap. The skin perforators are marked accordingly with a handheld Doppler. The superior margin of the flap is typically marked 1 cm below the gluteal fold, and the inferior margin is marked about 7–8 cm below, to make up for the width of the flap. An elliptical flap is designed, usually measuring about 27 cm transversely with an anterior extension to the adductor longus ( Fig. 6.2 ).

Vertical Flap Design

The VPAP flap perforators are identified using preoperative imaging. Their locations are confirmed using a handheld Doppler in the harvest position, which is typically lithotomy. The posterior edge of the gracilis muscle marks the anterior aspect of the flap. This allows for maximal versatility – in the event that the perforators are not adequate, the flap can be converted to a vertical gracilis muscle flap. The width of the skin paddle should not exceed 8 cm, but varies according to the patient-specific skin laxity ( Fig. 6.3 ).

Flap Dissection

The patient is preferably placed in the supine “frog-leg” position or in lithotomy position. The lithotomy position is preferred for the vertical flap design dissection. For the transverse skin pattern dissection, the anterior aspect of the flap is first incised and the dissection then proceeds to the superficial fascia. In order to optimize volume, conservative beveling can be performed during the initial dissection. However, beveling superiorly should be limited, to avoid disturbing the inferior buttock and gluteal fold. The fascia is entered over the gracilis muscle. The latter is retracted anteriorly and the fascia of the adductor magnus is incised. The dominant perforator is identified usually 2–3 cm posterior to the gracilis muscle. The dissection is then continued using standard perforator dissection technique in order to harvest the desired pedicle length and vessel diameter, which occurs deep to the adductor magnus muscle. The pedicle measures approximately 10 cm in length and is approximately 2.3–2.7 mm in diameter.

The vertical flap design is incised at the posterior edge of the gracilis muscle as described above and the dissection is continued without beveling the skin through the muscle fascia, and then the flap elevation is carried from anterior to posterior with the bipolar cautery. Once the favorable perforator vessel is identified, dissection continues in the standard fashion to identify the profunda femoris vessels from which the pedicle is divided. The length of the pedicle is similar to the transverse design with approximately 10 cm in length and 2.3–2.7 mm in vessel diameter ( Figs. 6.4–6.6 ).