Monitoring flap for buried free tissue transfer: its importance and reliability

To improve the success rate of microsurgical flap transfers into a buried area, it is important to monitor the circulation of the flap during the early stage. A monitoring flap includes such advantages as simplicity, reliability, noninvasiveness, and the ability to continuously monitor the vascular status of various buried flaps. This article describes experiences related to the importance and reliability of a monitoring flap. A total of 109 flaps in 99 patients were treated with buried free flaps, including a monitoring flap, between 1990 and 1999. Forty-nine patients received a tubed free radial forearm flap with a skin-monitoring flap, and six received a free jejunal flap with a jejunal segment monitoring flap for the reconstruction of the esophagus. Vascularized fibular grafts with a skin monitoring flap or peroneus longus muscle monitoring flap were used for reconstructing the mandible in six patients and for treating osteonecrosis of the femoral head in 48 flaps in 38 patients. Monitoring flap abnormalities were indicated in 14 flaps; therefore, immediate revisions were performed on the pedicle of the monitoring flap and microanastomosis site. Among these 14 flaps, nine showed true thrombosis and five showed false-positive thrombosis. Among the nine flaps that showed true thrombosis, five were salvaged and four were finally lost. The false-positive thrombosis in the five flaps was attributed to torsion or tension of the perforator of the monitoring flap in three flaps, an unclear determination in one flap because the monitoring flap size was too small, and damage to the perforator in the last flap. The total thrombosis rate was 8.3 percent (nine of 109), and the failure rate of the free tissue transfer was 3.7 percent (four of 109). The overall sensitivity of the monitoring flap was 100 percent, the predictive value of a positive test was 64 percent (nine of 14), and false-positive results occurred in 36 percent (five of 14). The salvage rate was 55.6 percent. To improve the reliability of a monitoring flap, it is recommended that the size of the flap be larger than 1 x 2 cm to assess the arterial status, and that a perforator with the appropriate caliber be selected. When a monitoring flap is fixed to a previous incision line or a newly created wound, any torsion or tension of the perforator should be avoided. In conclusion, the current results suggest that a monitoring flap is a simple, extremely useful, and reliable method for assessing the vascular status of a buried free flap.     

A new technique of scarless expanded forehead flap for reconstructive surgery

The forehead flap is an ideal flap for reconstructive surgery, especially for that involving reconstruction of the face and neck. However, it is usually limited to use in nasal reconstruction, even when performed in conjunction with tissue expansion, because of the severe visible morbidity of the donor site. In this article, the author discusses his development of a new technique of forehead flap, performed in conjunction with tissue expansion, for reconstructive surgery without visible scarring at the donor site. The technique involved positioning a tissue expander in the forehead pocket under the occipitofrontal muscle and serially inflating the expander over a period of approximately 4 to 6 weeks. Thereafter, an expanded forehead flap was created from the frontal hairline area on the basis of the location of the superficial temporal vessels and transferred into 16 recipient sites in 13 patients as an island flap (n = 8), a free flap (n = 1), or a local random flap (n = 7). The donor site was closed directly into the frontal hairline, without any visible scar. With the author's experience in the use of the island flap for nasal, facial, and neck reconstruction and of the free flap for reconstruction in the extremities, the flap could be as large as 8 x 18 cm without inducing flap necrosis or problems with donor-site closure. All patients (n = 13) had acceptable donor-site aesthetic results, without visible scarring. The results indicate that the flap could be a safe, ample, and color-matched flap for reconstruction of the face and neck and could also diminish donor-site morbidity to a minimum, without an unsightly visible scar. Furthermore, the flap could be formed into a customized free flap, with the above-mentioned advantages, to be transferred to any part of the body.     

Comparison of the effect of bacterial inoculation in musculocutaneous and fasciocutaneous flaps

The skin fascial flap is now recognized as a reliable flap for use in reconstructive surgery. The fasciocutaneous flap has been advocated for coverage of chronic infected wounds after debridement as an alternative to the musculocutaneous flap. Previous experimental and clinical studies have demonstrated the superior resistance of the musculocutaneous flap as compared to the random-pattern flap to bacterial inoculation. A canine model is presented for comparison of the effect of bacterial inoculation in fasciocutaneous and musculocutaneous flaps of similar dimensions. The area of skin necrosis secondary to bacterial inoculation was similar in these two flap types despite greater blood flow and skin oxygen in the fasciocutaneous flap. In a study of closed wound spaces formed by the deep surface of these two flap types, a greater degree of inhibition and elimination of bacterial growth and more collagen deposition are observed in the musculocutaneous wound space than in the fasciocutaneous flap.     

Optimizing autologous breast reconstruction in thin patients

Breast reconstruction with a transverse rectus abdominis myocutaneous (TRAM) flap plus an implant has been proposed as an option for women with a thin body habitus who do not have sufficient abdominal tissue to permit reconstruction with a TRAM flap alone. The standard autologous tissue reconstructive procedure in these women is a combined latissimus dorsi myocutaneous flap and breast implant. We reviewed our experience performing TRAM flap/implant and latissimus dorsi flap/implant breast reconstruction to compare complication rates and aesthetic outcomes between these two types of reconstruction. Between 1992 and 1999, 88 breasts were reconstructed at our institution using an autologous tissue flap combined with a breast implant (44 with a TRAM flap/implant and 44 with a latissimus dorsi flap/implant). Recipient-site and donor-site complications for the two procedures were compared using Fisher's exact test; a panel of unbiased, blinded judges compared the aesthetic outcomes. The recipient-site complication rate was lower for the TRAM flap/implant group than for the latissimus dorsi flap/implant group (18 percent versus 34 percent, p = 0.09). Most recipient-site complications in the TRAM flap/implant group were related to fluid collection around the implant. In the TRAM flap/implant group, complications occurred in 37 percent of the reconstructions that had immediate implant placement and in none of the reconstructions with delayed implant placement (p = 0.01). In the TRAM flap/implant reconstructions with immediate implant placement, the recipient-site complication rate was 50 percent when implants were completely filled with saline, but no complications occurred with incompletely filled, postoperatively adjustable implants (p = 0.03). No microvascular complications occurred with immediate placement of breast implants under TRAM flaps. Donor-site complications included a hematoma, a seroma, and an umbilical necrosis in the TRAM flap/implant group and six cases of seroma formation in the latissimus dorsi flap/implant group. The comparison of aesthetic outcome was statistically significant for the TRAM flap/implant group, which had a higher overall mean score than the latissimus dorsi flap/implant group did (3.29 versus 2.85, p = 0.01). The results of this study suggest that the TRAM flap/implant breast reconstruction should be considered as an alternative to the latissimus dorsi flap/implant breast reconstruction in women with a thin body habitus.     

Frontalis musculocutaneous island flap for coverage of forehead defect

The use of the frontalis musculocutaneous flap as a pedicle island flap offers some advantages in frontal reconstruction. It can be used for immediate reconstruction following the ablation of a small or moderate area, even after harvesting of the frontal flap for nasal reconstruction. Because of its intact lateral bundle, it has the potential to carry some sensory innervation, albeit minimal, to the reconstructed area. We have found the frontalis musculocutaneous flap, when used as a pedicle island flap, to be an adaptable and dependable alternative flap for repairs after small or moderate resections in the frontal region. This flap could be performed immediately and in one stage, have a low morbidity rate, and allow a rapid aesthetic restoration; and, it is easy to perform. In two cases, we have observed some degree of venous congestion in the island during the early postoperative period but with success in final healing. The experience demonstrates that this flap should be considered as another valuable tool in reconstructive efforts directed at the forehead. We propose a novel method for the forehead reconstruction using the frontalis musculocutaneous island flap. A case is presented that demonstrates the use of this flap for repair in a depressed frontal defect.     

The great potential of the intercostal flap for torso reconstruction.

The intercostal flap has many uses for torso reconstruction, whether employed as an island flap or a free flap. With modifications, it can be used as a sensory skin flap, or as a compound osteocutaneous flap to restore stability in a chest wall construction, or as a skin flap with a permanent blood supply to provide stable cover after excision of radiation ulcers.     

The characterization of a mammalian DNA structure-specific endonuclease.

The repair of some types of DNA double-strand breaks is thought to proceed through DNA flap structure intermediates. A DNA flap is a bifurcated structure composed of double-stranded DNA and a displaced single-strand. To identify DNA flap cleaving activities in mammalian nuclear extracts, we created an assay utilizing a synthetic DNA flap substrate. This assay has allowed the first purification of a mammalian DNA structure-specific nuclease. The enzyme described here, flap endonuclease-1 (FEN-1), cleaves DNA flap strands that terminate with a 5' single-stranded end. As expected for an enzyme which functions in double-strand break repair flap resolution, FEN-1 cleavage is flap strand-specific and independent of flap strand length. Furthermore, efficient flap cleavage requires the presence of the entire flap structure. Substrates missing one strand are not cleaved by FEN-1. Other branch structures, including Holliday junctions, are also not cleaved by FEN-1. In addition to endonuclease activity, FEN-1 has a 5'-3' exonuclease activity which is specific for double-stranded DNA. The endo- and exonuclease activities of FEN-1 are discussed in the context of DNA replication, recombination and repair.     

Dynamic removal of replication protein A by Dna2 facilitates primer cleavage during Okazaki fragment processing in Saccharomyces cerevisiae

Eukaryotic Okazaki fragments are initiated by a RNA/DNA primer, which is removed before the fragments are joined. Polymerase delta displaces the primer into a flap for processing. Dna2 nuclease/helicase and flap endonuclease 1 (FEN1) are proposed to cleave the flap. The single-stranded DNA-binding protein, replication protein A (RPA), governs cleavage activity. Flap-bound RPA inhibits FEN1. This necessitates cleavage by Dna2, which is stimulated by RPA. FEN1 then cuts the remaining RPA-free flap to create a nick for ligation. Cleavage by Dna2 requires that it enter the 5'-end and track down the flap. Because Dna2 cleaves the RPA-bound flap, we investigated the mechanism by which Dna2 accesses the protein-coated flap for cleavage. Using a nuclease-defective Dna2 mutant, we showed that just binding of Dna2 dissociates the flap-bound RPA. Facile dissociation is specific to substrates with a genuine flap, and will not occur with an RPA-coated single strand. We also compared the cleavage patterns of Dna2 with and without RPA to better define RPA stimulation of Dna2. Stimulation derived from removal of DNA folding in the flap. Apparently, coordinated with its dissociation, RPA relinquishes the flap to Dna2 for tracking in a way that does not allow flap structure to reform. We also found that RPA strand melting activity promotes excessive flap elongation, but it is suppressed by Dna2-promoted RPA dissociation. Overall, results indicate that Dna2 and RPA coordinate their functions for efficient flap cleavage and preparation for FEN1.     

Two options for perforator flaps in the flank donor site: latissimus dorsi and thoracodorsal perforator flaps

Two types of perforators, septocutaneous and musculocutaneous, are found in the same donor site of the flank area, and two perforator flaps based on each perforator are clinically available. Therefore, it is necessary to distinguish them from one another using different nomenclatures. Accordingly, the perforator flap based on a musculocutaneous perforator is named according to the name of the muscle perforated, the latissimus dorsi perforator flap, and the perforator flap based on a septocutaneous perforator, located between the serratus anterior and latissimus dorsi muscles, is named according to the name of the proximal vessel, the thoracodorsal perforator flap. In this series of 42 latissimus dorsi perforator flaps, flap size ranged from 5 x 3 cm to 20 x 15 cm, and two complications were observed: a marginal necrosis in an extremely large flap (26 x 12 cm) and a failure caused by infection. The thoracodorsal perforator flap was used in 14 cases, including two cases of chimeric composition. Flap size ranged from 4.5 x 3.5 to 18 x 15 cm, with no complications. In the two patterns of perforator flap that the author used, initial temporary flap congestion was observed in five latissimus dorsi perforator flap cases and two thoracodorsal perforator flap cases, when the flap was designed as a large flap or a less reliable perforator was selected. However, the congestion was not serious enough to cause flap necrosis. Several techniques, such as T anastomosis or inclusion of an additional perforator or a small portion of muscle, are recommended to prevent the initial flap congestion, especially when an unreliable perforator is inevitably used or when a flap larger than 20 cm long is required. A small portion of the muscle was included in six cases, when an unduly large or improperly long flap was planned. All of the flaps were successful and ranged from 22 x 7 to 15 x 28 cm, except for one case of distal flap necrosis in an extraordinarily large flap measuring 34 x 10 cm. Diverse selection of the perforator flap is one of the great advantages of the flank donor site, providing it with wider availability and more versatile composition for reconstruction or resurfacing.     

Our experience with combined procedures in aesthetic plastic surgery

The instep flap needs neither muscle nor a transposition base for survival or innervation. It can be transposed as an island fasciocutaneous flap either on the medial or lateral plantar neurovascular bundles or both, and it can be transferred also as a free flap from the opposite foot. Four cases demonstrating the use of the flap as an island and free flap are presented with follow-up ranging from 1 to 2 years. The absence of muscle in the flap provides greater stability of the heel reconstruction and results in a lesser secondary defect. Sensation in the flaps is diminished but adequate for long-term function, but hyperkeratotic reaction remains an unpredictable problem. The ability to transfer the flap as a free transfer widens the scope of the flap to reconstruct both heel and forefoot defects where local instep tissue or vascularity are inadequate for local reconstruction. The secondary defect, particularly when no muscle is included in the flap, has been minimal.     

Deltopectoral skin flap as a free skin flap revisited: further refinement in flap design, fabrication, and clinical usage

The deltopectoral skin flap is an axial flap; therefore, it can be fashioned as a free skin flap. Although color and texture of the skin are well suited for facial resurfacing, the structural features of inconsistent thickness of the skin, a short vascular pedicle, a minute caliber of the nutrient vessel, and donor site morbidity often preclude the use of this flap for this purpose. The deltopectoral skin flap fabricated as a free skin flap transferred by means of a microsurgical technique was used in 27 patients between 1985 and 1998 at our hospital. The anterior perforating branches of the internal mammary vessels were the primary nutrient vessels of the flap in seven instances. The external caliber of this artery varied between 0.6 mm and 1.2 mm, with an average size of 0.9 mm. The size of the accompanying vein varied between 1.5 mm and 3.2 mm, with an average of 2.3 mm. Coaptation of these vessels with those in the recipient site was technically difficult. Thrombosis occurred at the anastomotic site in three patients, requiring reoperation. Two flaps were saved. The flap failure was drastically reduced in the remaining 20 patients by including a segment of the internal mammary vessel when fabricating the vascular pedicle. The size of the internal mammary arterial segment averaged 2.1 mm, and the average size of the accompanying vein was 2.9 mm. The problem of a bulky flap was managed by surgical defatting/thinning of the flap at the time of flap fabrication and transfer. A V-to-Y skin flap advancement technique of wound closure was used in eight individuals. The flap donor-site morbidities were minimized with this method of wound closure.     

A versatile one-stage neurovascular flap for fingertip reconstruction: the dorsal middle phalangeal finger flap.

The dorsal middle phalangeal finger flap is an extremely reliable flap that is indicated for fingertip injuries which require sensory reconstruction. This flap originates from the dorsum of the middle phalanx of the finger and is elevated with a vascular pedicle of the digital artery and the dorsal branch of the digital nerve. After transfer of the flap to the injured site, epineural neurorrhaphy is done between the digital nerve and the dorsal sensory branch of the flap. This flap can be thought of as an island flap of the innervated cross-finger flap that provides excellent sensory recovery and aesthetic improvement. We used this flap in a series of eight consecutive patients and were able to follow up seven patients for longer than 6 months (mean follow-up time 10.7 months). All patients achieved measurable two-point discrimination, with an average of 4.9 mm in the moving two-point discrimination. In this study, we report our consecutive series of the dorsal middle phalangeal finger flap and its versatile utility.     

The thoracodorsal artery perforator flap: clinical experience and anatomic study with emphasis on harvest techniques

The thoracodorsal artery perforator flap is a relatively new flap that has yet to find its niche in reconstructive surgery. At the authors' institution it has been used for limb salvage, head and neck reconstruction, and trunk reconstruction in cases related to trauma, burns, and malignancy. The authors have found the flap to be advantageous for cranial base reconstruction and for resurfacing the face and oral cavity. The flap has been used successfully for reconstruction of traumatic upper and lower extremity defects, and it can be used as a pedicled flap or as a free tissue transfer. The perforating branches of the thoracodorsal artery offer a robust blood supply to a skin-soft-tissue paddle of 10 to 12 cm x 25 cm, overlying the latissimus dorsi muscle. The average pedicle length is 20 cm (range, 16 to 23 cm), which allows for a safe anastomosis outside the zone of injury in traumatized extremities; the flap can be made sensate by neurorrhaphy with sensory branches of the intercostal nerves. Vascularized bone can be transferred with this flap by taking advantage of the inherent vascular anatomy of the subscapular artery. A total of 30 pedicled and free flap transfers were performed at the authors' institution with an overall complication rate of 23 percent and an overall flap survival rate of 97 percent. Major complications, such as vascular thrombosis, return to the operating room, fistula formation, recurrence of tumor, and flap loss, occurred in 17 percent of the patients. Despite these drawbacks, the authors have found the thoracodorsal artery perforator flap to be a safe and extremely versatile flap that offers significant advantages in acute and delayed reconstruction cases.     

Temporoparietal fascial flap for orbital and eyelid reconstruction.

The temporoparietal fascial flap is a recognized technique for the transfer of vascularized tissue in the craniofacial region. The flap has a predictable axial vessel, provides thin vascularized tissue, and can be harvested with minimal donor-site morbidity. The temporoparietal fascial flap is well suited for orbital or eyelid reconstruction because of its proximity to the orbit. The flap is useful for reconstruction of anatomic barriers between the orbit, intracranial cavity, and paranasal sinus spaces. We present four patients in whom the temporoparietal fascial flap was used for orbital reconstruction following extirpative surgery for orbital neoplasm and two patients in whom the flap was used for lower eyelid and malar reconstruction.     

The VY tensor fasciae latae musculocutaneous flap

When first introduced in 1978, the tensor fasciae latae flap was used both as a free-tissue transfer and as a local rotational flap. Its use as a free flap has diminished as other more appropriate flaps for free-tissue transfer have been described. The tensor fasciae latae flap has remained, however, an instrumental flap in the coverage of anterior and posterior soft-tissue defects around the hip region. The purpose of this paper is to present a new design of the tensor fasciae latae flap in the coverage of trochanteric pressure sores. By essentially creating a VY advancement flap into the trochanteric defect with the tensor fasciae latae, one can cover the trochanteric defect with the best-vascularized portion of the flap and avoid the dog-ear deformity.     

A newly defined conchal floor arterial flap for auricular reconstruction

A conchal floor composite flap pedicled by skin of the helical crus has been well described in the literature. Here the flap is elevated based on the supply by an upper auricular branch of the superficial temporal artery. In this article, a newly defined conchal floor arterial flap is proposed. The flap is based on the main stem of the posterior auricular artery and its venae comitantes. Two types of conchal floor arterial flaps were elevated: a proximally based chondral arterial flap and a distally based chondrocutaneous arterial flap. The proximally based flap was used for earlobe reconstruction, whereas the distally based flap was useful in the reconstruction of the upper auricle. Nine congenital auricular malformations were successfully corrected with this newly defined conchal floor flap procedure. This type of flap is easier to elevate, more reliable, and more versatile than the one currently in use.     

The lower trapezius musculocutaneous flap from pedicled to free flap: anatomical basis and clinical applications based on the dorsal scapular artery

The pedicled lower trapezius musculocutaneous flap is a standard flap in head and neck reconstruction. A review of the literature showed that there is no uniform nomenclature for the branches of the subclavian artery and the vessels supplying the trapezius muscle and that the different opinions on the vessels supplying this flap lead to confusion and technical problems when this flap is harvested. This article attempts to clarify the anatomical nomenclature, to describe exactly how the flap is planned and harvested, and to discuss the clinical relevance of this flap as an island or free flap. The authors dissected both sides of the neck in 124 cadavers to examine the variations of the subclavian artery and its branches, the vessel diameter at different levels, the course of the pedicle, the arc of rotation, and the variation of the segmental intercostal branches to the lower part of the trapezius muscle. Clinically, the flap was used in five cases as an island skin and island muscle flap and once as a free flap. The anatomical findings and clinical applications proved that there is a constant and dependable blood supply through the dorsal scapular artery (synonym for the deep branch of the transverse cervical artery in the case of a common trunk with the superficial cervical artery) as the main vessel. Harvesting an island flap or a free flap is technically demanding but possible. Planning the skin island far distally permitted a very long pedicle and wide arc of rotation. The lower part of the trapezius muscle alone could be classified as a type V muscle according to Mathes and Nahai because of its potential use as a turnover flap supplied by segmental intercostal perforators. The lower trapezius flap is a thin and pliable musculocutaneous flap with a very long constant pedicle and minor donor-site morbidity, permitting safe flap elevation and the possibility of free-tissue transfer.     

From the "charretera" to the supraclavicular fascial island flap: revisitation and further evolution of a controversial flap

Wide tissue defects located on the face and neck area often require distant flaps or free flaps to achieve a tension-free reconstruction together with an acceptable aesthetic result. The supraclavicular island flap surely represents a versatile and useful flap that can be used in case of large tissue losses. Because of its wide arc of rotation, which ensures a 180-degree mobilization anteriorly and posteriorly, the flap can reach distant sites when harvested as a pure island flap. The main vascular supply of the flap, the supraclavicular artery, a branch of the transverse cervical artery or, less frequently, of the suprascapular artery, though reliable, is not a very large vessel. In some particular cases, when too much tension or angles that are too tight are present, the vascular supply of the flap can be difficult and special care must be taken to avoid flap failure. To avoid this problem, the authors started harvesting the flap not as a pure island flap but with a fascial pedicle, thin and resistant, which ensures good reliability; also, when a higher tension rate is present, it avoids the risk of excessive traction or kinking of the vessels. Twenty-five consecutive patients with various defects located on the head, neck, and thorax area were treated in the past 2 years using the modified supraclavicular island flap. There was no flap loss or distant necrosis of the flap, and there was marginal skin deepithelialization in only two cases, which only required minor surgery. Postoperative morbidity was low, similar to the classic supraclavicular island flap, with primarily closed donor sites, except for one case, and tension-free scars. The authors show how the modified supraclavicular island flap is a reliable and safe flap that gives a good aesthetic result with low risk concerning the viability of the transferred skin. The technique, similar to supraclavicular island flap harvesting, is easy to perform and is attractive in patients at risk for poor or delayed healing such as smokers or patients with complex medical histories.     

Innervated radial thenar flap combined with radial forearm flap transfer for thumb reconstruction

A radial thenar flap combined with radial forearm flap was used for the reconstruction of the ipsilateral thumb in four patients. Vascular supply of the combined flap was based on the radial artery and extending the vascular pedicle to the superficial palmar branch of the radial artery. The flap was sensated by the palmar branch of the superficial radial nerve. The size of the flap averaged 15 x 5 cm and the innervated region of the thenar eminence was an area approximately 5 x 3 cm located over the proximal parts of the abductor pollicis brevis and opponens pollicis muscles. The flap was transferred as a free flap in three patients and as an advancement flap in one patient. The flaps survived completely without complications. Satisfactory restoration of sensation was achieved in the flap area, as shown by 6 mm of average moving two-point discrimination. This combined flap may be a feasible reconstructive option for large palmar defects of the fingers such as degloving injuries.     

Free anterolateral thigh adipofascial perforator flap

The anterolateral thigh adipofascial flap is a vascularized flap prepared from the adipofascial layer of the anterolateral thigh region. It is a perforator flap based on septocutaneous or musculocutaneous perforators of the lateral circumflex femoral system. With methods similar to those used for the free anterolateral thigh flap, only the deep fascia of the anterolateral thigh and a 2-mm-thick to 3-mm-thick layer of subcutaneous fatty tissue above the fascia were harvested. In 11 cases, this flap (length, 5 to 11 cm; width, 4 to 8 cm) was used for successful reconstruction of extremity defects. Split-thickness skin grafts were used to immediately resurface the adipofascial flaps for eight patients, and delayed skin grafting was performed for the other three patients. The advantage of the anterolateral thigh adipofascial flap is its ability to provide vascularized, thin, pliable, gliding coverage. In addition, the donor-site defect can be closed directly. Other advantages of this flap, such as safe elevation, a long wide vascular pedicle, a large flap territory, and flow-through properties that allow simultaneous reconstruction of major-vessel and soft-tissue defects, are the same as for the conventional anterolateral thigh flap. The main disadvantage of this procedure is the need for a skin graft, with the possible complications of subsequent skin graft loss or hyperpigmentation.