Tensor fascia latae perforator flap: An alternative reconstructive choice for anterolateral thigh flap when no sizable skin perforator is available.

INTRODUCTION: The anterolateral thigh flap (ALT) is a versatile flap and very useful for the reconstruction of different anatomical districts. The main disadvantage of this flap is the anatomical variability in number and location of perforators. In general, absence of perforators is extremely rare. In literature, it is reported to be from 0.89% to 5.4%. If no sizable perforators are found, an alternative reconstructive strategy must be considered. Tensor fascia lata (TFL) perforator flap can be a good alternative in these cases: Perforator vessels are always present, the anatomy is more constant and it is possible to harvest it through the same surgical access. The skin island of the flap can be very large and can be thinned removing a large part of the muscle allowing its use for almost the same indications of the ALT flap.
MATERIALS AND METHODS: We report 11 cases of reconstruction firstly planned with the ALT flap, then converted into TFL perforator flap. RESULTS AND
CONCLUSION: The result was always satisfactory in terms of the donor site morbidity and reconstructive outcome.

INTRODUCTION

The Anterolateral thigh flap (ALT) is a versatile flap, very useful for the reconstruction of a wide variety of defects as free or pedicled flap.[1] Nowadays, ALT free flap is considered the gold standard for head and neck reconstruction;[2] as pedicled flap it is indicated in the reconstruction of the abdominal wall.[3] The main disadvantage of this flap is the anatomical variability of perforators, in number and location. The mean number of perforators is reported to be from 1.69[4] to 2.3 per flap,[5] with an average perforator artery diameter at the fascial level of 1 + 0.08 mm.[4] In general, absence of sizable perforators is extremely rare. In literature, it is reported to be from 0.89% to 5.4%.[56]

In our experience, tensor fascia latae (TFL) flap can be a good alternative if no sizable perforators for ALT flap are found. Nahai, et al. first described the TFL flap in 1978;[7] the vascular pedicle is the transverse branch of the lateral circumflex femoral artery and 5-7 perforator vessels are always present[8] and hence TFL perforator flap can be the harvested by the same surgical access used for the ALT flap. The skin island of the flap can be very large ranging from 15 cm × 12 cm to 22 cm × 11 cm.[91011] Moreover, if the harvested as a perforator flap, it can be thinned removing a large part of the muscle allowing its use for almost the same indications of the ALT flap. Potential drawbacks of this flap include bulkiness of the reconstructed area, depressed scars in of the donor site and reduced range of motion of the knee.

We report 11 cases of reconstruction firstly planned with ALT flap and then converted in reconstructions with TFL perforator flap because no sizable perforators were founded.

MATERIALS AND METHODS

From 1992 to May 2012, a total of 191 patients underwent different kind of reconstructions planned with ALT flap at Sant’Orsola-Malpighi hospital. Among these patients, 11 patients did not have sizable perforator vessels in the ALT region (with a percentage of absence of perforators of 5.7%, comparable to those reported by Wei et al.[6]).

There were 10 men and 1 woman with an average age of 66 years (age range from 54 years to 78 years). Nine patients received ablation surgery for head and neck cancer and ALT flap was planned as a free flap [Figures 1 and 2]; the other two patients had soft-tissue defects of the abdominal wall after bowel surgery and ALT flap was planned as pedicled flap [Figure 3].

Figure 1

Neck reconstruction with tensor fascia latae (TFL) flap (a) parastomal recurrence of carcinoma. (b) reconstruction planned with anterolateral thigh flap and then converted in TFL. (c) TFL flap harvested. (d) final result

Figure 2

Cheek reconstruction with tensor fascia latae (TFL) flap (a) squamocellular carcinoma of the preauricolar region. (b) reconstruction planned with anterolateral thigh flap and then converted in thinned TFL. (c) final result with a good volume reconstruction

Figure 3

Abdominal wall reconstruction with tensor fascia latae pedicle flap (a) dehiscence of abdominal wall closure with multiple fistulas. (b) defect after wound toilette. (c) final result, donor site closed with skin graft. (d) result after 3 months

In these cases, an alternative flap needed to be performed for the reconstruction and we chose the TFL perforator flap.

We started the dissection of ALT flap from the medial side of the thigh, but we didn't find sizable perforators in suprafascial and subfascial plane. Hence, we decided to explore perforators in the TFL region through the same surgical incision. The dissection continued cranially in the subfascial plane in the ALT region, which became a submuscular plane in the TFL muscle region. Perforators were identified in this region and used to harvest a TFL perforator fasciocutaneous flap, dissecting the perforator trough the muscle. Dissection of the perforator through the muscle allowed harvesting a flap that is similar to ALT flap in thickness. A retractor is used to expose the transverse branch of the lateral circumflex femoral artery through the intermuscular space between the TFL muscle and the rectus femoris muscle; the dissection of the perforator was performed back to the transverse branch of the lateral circumflex femoral artery or proceeded as far as to the lateral circumflex femoral artery, depending on the desired pedicle length. Then, the flap was thinned in order to reduce its bulkiness depending on the desired volume: If harvested as a perforator flap, large part of the muscle was removed, preserving it as a cuff only around the selected perforator [Figure 4].

Figure 4

Perforator dissection is performed within tensor fascia latae muscle

RESULTS

In all the patients who had no sizable perforators for ALT flap, we harvested TFL perforator flap. In all cases, we found a pedicle of good calibre and desired length. The mean length of the pedicle was 8 cm (range, 6-10 cm) and the average diameter was 4 mm (range, 1-5 mm). The skin island dimension ranged from 15 cm × 10 cm to 28 cm × 17 cm. All the flaps harvested were thinned to obtain pliable tissue for the reconstructive requests. The donor site was closed directly in 9 cases and with a split-thickness skin graft in 1 case.

We didn't have complications in this series of patients. Particularly, we didn't observe any of the common complications described elsewhere for this flap, such as bulkiness of the reconstructed region, depressed scar in the donor area and reduced range of motion of the knee.

DISCUSSION

ALT flap is nowadays, the gold standard in head and neck reconstructions as free flap and in abdominal wall reconstruction as pedicle flap. This flap offers a good volume of pliable tissues and a pedicle characterized by good calibre and adequate length; its main disadvantage is its anatomical variability in number and location of perforator vessels. The absence of perforators is rare, but possible; in literature is reported in a percentage ranging from 0.89% to 5.40%. In our experience, TFL perforator flap can be a good alternative. Other authors reported this possibility in small series.[1011] TFL flap allows to use the same donor site avoiding another surgical incision. Its anatomy is more constant;[8] perforators are always present and its pedicle is sufficiently long with an average length of 8 cm. As a perforator flap, a thinner and more pliable flap [Figures 5 and 6] can be obtained, removing a variable portion of muscular tissue and leaving only a cuff around the pedicle. For these reasons, it can be used for almost the same indications of ALT flap, particularly as free flap in the reconstruction of many facial districts as tongue, oral floor and retro-molar space; as pedicle flap, it is useful in abdominal wall reconstructions. Other alternatives were possible, but the TFL perforator flap was the best choice in our opinion because it allowed maintaining the same reconstructive plan made with the ALT flap. A muscular flap such as vastus lateralis flap did not allowed to maintain the same plan in terms of skin islands and flap disposition. Furthermore, the anteromedial flap could be an alternative; however, in our experience, TFL perforator flap dissected trough the TFL muscle was not of significantly different thickness and allowed maintaining the reconstructive plan and patient position.

Figure 5

Tensor fascia latae flap can be thinned obtaining a more pliable flap

Figure 6

Tensor fascia latae flap was thinned for the reconstruction of the palate and nasal cavity

CONCLUSION

When ALT flap harvesting is not possible for the absence of reliable perforator vessels, the TFL perforator flap can be a good alternative. The dissection can be made through the same incision, without impairment of other donor sites. The reconstructive plan doesn't need any change; in fact, the TFL flap offers a good volume of skin and can be thinned removing a variable portion of muscle allowing its use for almost the same indication as ALT flap.