gms | German Medical Science

Much time has passed, since the first free flaps were transplanted by plastic and reconstructive surgeons in the early seventies of the last decade. Since then, a tremendous number of flaps have been developed. As the knowledge of possible angiosomes continues to grow, sizing and even composing a variety of possible tissues for reconstructive measures seems to be without limitations. As the surgical result not only depends on a successful flap transfer but also on the harvest, this paper discusses the surgical techniques for the first total endoscopic harvest of a serratus fascia flap for free flap transplantation to the lower leg. In the past, we transferred a larger number of flaps from the A. subscapularis angiosome. We used the M. Serratus anterior fascia flap more frequently for lower leg reconstruction. The advantage of a possible long pedicle , the pliability and the thin appearance made this flap our favourite application for palmsize or smaller soft tissue deficiency. Despite this successful reconstructive tool, we were not pleased with the so-called donor site morbidity. The conventional harvest of flaps out of the subscapularis region often results in a scar from axilla to midthorax. Over and above the scar, a prolonged postoperative secretion or seroma formation and finally potential difficulties in elevating the arm are possible complications. To reduce the potential complications from such a flap harvest, we developed a method for the total endoscopic harvest of the serratus anterior fascia/muscle flap.

In September 2012 we performed the first total endoscopic serratus anterior fascia free flap harvest. The patient was diagnosed with an osteo-cutaneous fistula at the medial ankle due to a chronic osteomyelitis following a complicated fracture of the tibial bone. After debridement of bone and soft tissues, the affected tissue/skin was approximately 5x7 cm in size. Since the angiography showed no signs of peripheral artery disease (PAD), a free flap reconstruction was planned. Increasing the risk for this procedure was a strong nicotine substance abuse and a severe COPD.

The patient is positioned in a lateral decubitus position on a bean bag, the arm is elevated on a Mayo stand. Before harvesting the flap, as for each patient the debridement, microsurgical preparation of the recipient vessels and measuring of the soft tissue deficiency was undertaken. For the flap harvest, we first marked the anterior border of the latissimus dorsi muscle. The incision of 2.5 cm length started 8 cm in front of this line at level with the midthorax following the relaxed skin tension lines (RSTL) (Figure 1 [Fig. 1]). We then inserted a flexible laparoscopic single port system (SILS, Covidien, Mansfield, MA 02048, USA) and started gas insufflation (Figure 2 [Fig. 2]). We used a 5mm endoscope (Storz, Tuttlingen, Germany) for visualization and a 5 mm Ligasure System (Covidien, Mansfield, MA 02048, USA) for dissection (Figure 3 [Fig. 3]). We used this setting to meticulously prepare a neo cavity between M. latissimus dorsi and M. serratus anterior (Figure 4 [Fig. 4]).The safe dissection and secure protection of the thoraco-dorsal vessels being of utmost importance. After the vessels were dissected up to the axilla, the thoraco-dorsal nerve was separated. Endoscopic technique facilitates a high magnification for proper and secure identification of this formation. The cranial muscle was put under moderate tension by lifting it up with clamp towards the subcutaneous tissue. Using this setting the blunt spreading of nerve and vessels was performed with the use of a Ligasure dolphin tip laparoscopic instrument and the assistance of a 5 mm straight laparoscopic clamp without causing any damage to the pedicle or the nerve. After complete identification of the serratus vessels and defining the flap size, we began the incision of the serratus fascia. With a second auxiliary incision we used a 5 mm clamp to support the raising of the fascia flap from the underlying muscle. As the fascia was thin and fragile, we decided to take a little of the underlying muscle to increase the reliability of the flap without reducing the function of the serratus muscle (Figure 5 [Fig. 5]). Finally we separated the so-called serratus arcade and clipped the vessels of the latissimus dorsi muscle and clipped the flap vessels at the Arteria and Vena axillaries (Figure 6 [Fig. 6]). The flap was extracted via the 2.5 mm incision. A second look into the neo cavity showed a non bleeding harvest area and safely clipped vessels. The harvest area was left with a drainage catheter of 16 Ch. The incision was closed in intracutaneous fashion.

We were able to perform a total endoscopic harvest of a serratus fascia flap for free flap reconstruction of soft tissues. With this new operative technique we were able to avoid the typical skin incision of approx. 20 to 30 cm associated with such a free flap harvest. It is likely that this lowers the morbidity at the harvest area enormously. The endoscopic procedure took 1 hour 50 minutes. The flap was transferred to the lower leg and was fitted into the soft tissue deficiency. Following microsurgical anastomosis (Figure 7 [Fig. 7]) and split skin graft transfer, the further postoperative course was uneventful. Due to complete flap healing the patient started ambulating five days following the operation (Figure 8 [Fig. 8]). From the first post-operative day, the donor site was without pain (maximum 2 VAS) and the patient was able to move and elevate the arm naturally as prior to the operation. The patient showed no scapula alata and a normal contraction of the M. latissimus dorsi was seen. The suction drain at the thorax was extracted after 6 days.

Over the last decades, the development of endoscopic surgery has been huge. Especially in the fields of gynecology, urology and visceral surgery a lot of endoscopic techniques have become the standard procedures. Despite the rapid development of plastic and reconstructive surgery, endoscopic procedures aren’t very widespread. Reconstructive microsurgery aims to achieve low morbidity at the donor site. To achieve this goal a large number of flaps have been developed. Still the A. subscapularis angiosome is one of the most important donor sites. Especially the Serratus anterior fascia flap seems to be an important tool for free flap reconstruction in many cases [1], [2], [3].

Looking at plastic reconstructive surgery the use of endoscopic respectively laparoscopic techniques have been reported in the laparoscopic harvest of omentum and jejunum for free flap transfer [4], [5], [6], [7]). These techniques in our view should be applied on an exceptional basis only because of the high risk for complication. They are therefore not suitable as standard procedures. As a result of the limited size and the short pedicle, the reported endoscopic harvest of a temporalis fascia flap [8], [9], [10] represents the highest standards of surgical technique, but its use is likely quite limited. As regards the A. subscapularis angiosome, there are reports about endoscopically assisted harvests of mostly pedicled latissimus dorsi flaps for breast reconstruction [11], [12], [13]). To our knowledge, no reports exist on a total endoscopic harvest of a free flap from this area. All endoscopic assisted techniques of harvesting a free flap in this area imply the use of a wider axillary incision [14], [15]. We couldn’t find any descriptions of a total endoscopic or endoscopically assisted harvest of a serratus fascia flap in literature.

The reasons for the thus far limited use of endoscopy in free flap harvest, appears in our opinion to be the problem of establishing a sufficient optic cavity [16]. This is a huge challenge as raising a flap mostly means preparation of defined layers, preservation of vascularization and opening of new, previously not existing space. We found a solution to this problem in the use of the flexible, gastight and properly fixated SILS port. After preparing a little cavity, the gas insufflation is able to span this space. The further development of the neo cavity is of preparatoric ease. The use of the ligasure system provides the almost bloodfree preparation which improves the optical conditions and leads to a secure harvest of the flap. The above-mentioned time needed for the endoscopic preparation is in our view only the beginning of the learning curve with this new technique and with further use thereof, the time required for the operation will be close to the time needed to undertake a conventional flap harvest.

The major advantage of the endoscopic procedure is primarily the avoidance of the incision from axilla to midthorax. A 20 to 30 cm long cut compared to a 2.5 cm incision ignores the aesthetic benefits of the almost painless postoperative course. The possibility of free arm and shoulder movement after the operation are inconceivable using the open technique. Our preparation doesn’t touch the axillary skin (Figure 9 [Fig. 9]), which is often associated with complicated healing. The use of a bipolar vessel sealer prevented loss of blood.

With the success of the total endoscopic flap harvest of the serratus fascia flap we have to consider a broader use of this technique. The endoscopic elevation of a serratus muscle flap should be without major complications, even a total endoscopic harvest of a latissimus muscle flap should be possible. In this case the first incision would be made further dorsal and for the final extraction of the flap, the skin incision must be lengthened.

We describe a new method for the total endoscopic harvest of the serratus fascia flap for free flap transfer. The harvest can be undertaken within a reasonable time and following surgery leaves the patient with minimal donor site morbidity compared to the open technique. We would like to stress that in our opinion following a well performed reconstruction (Figure 10 [Fig. 10]), the reduction of the so-called donor site morbidity is the second most important plastic reconstructive aim, as we do not want to harm an already injured patient at a second site.

The authors declare that they have no competing interests.