Cross-Leg Flaps: Preferred Alternative To Free Flaps?

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  • mesocaval shunting.Again, we thank the authors of this letter for their

    308 Letters J Am Coll Surgdurable and optimal anastomosis (to a short segment ofSMV at the mesenteric root). We, therefore, attach the in-ternal jugular vein conduit to the SMV with the intent ofnot revising this anastomosis; using a Dacron graft wouldnot be our preference. We also secondarily and brieflydescribed a method for wrapping a skeletonized SMA.This was performed using a saphenous vein graft whenthe artery required extensive dissection along with sutureclosure of a number of small arteries at the origin of theIPDAs and proximal jejunal branches. This additionalprocedure is certainly not always required and is unrelatedto the performance of a mesocaval shunt. Bovine pericar-dium might be sufficient for this purpose, but we havefavored autologous tissue. We have not seen complicationsof clinical significance with the use of additional incisionsin the neck or groin.The superficial femoral vein can certainly be used for

    creation of the mesocaval shunt or when replacing theSMV. We have modest experience with this conduit,but harvesting the superficial femoral vein is morecomplicated than the internal jugular vein, and legswelling can be a problem, even when being very carefulwith the harvest. We prefer the internal jugular vein as aroutine venous conduit and, with experience, one getsused to working with this vessel. We only use the greatersaphenous vein as a wrap when buttressing skeletonizedarteries, such as the SMA described here, or as an onlayvenous patch.In addition to allowing for complete diversion of portal

    flow to the porta hepatis, a substantial benefit afforded bythe use of a mesocaval shunt is the improved exposureof the SMA. Diverting the SMV into the IVC bothimproves the exposure and facilitates a much safer dissec-tion of the SMA.This is particularly important for borderline resectable

    pancreas tumors that have encased or occluded the SMV-PV and are also abutting the SMA. The SMA dissection,in these cases with an in situ SMV, is extremely difficultwith considerable risk of either injuring the SMA or per-forming an incomplete resection of the tumor.Finally, the mesocaval shunt does not always require

    revision. Particlarly in patients who are thin, the graftmight sit nicely at the end of the operation, withoutredundancy, and therefore not require any additionalintervention. If revision is required, as stated here, onemight not always have the luxury of revising the SMVanastomosis. Again, the techniques described in ourarticle were used in rare and very complex situationsthat most would consider outside the realm of surgicalresection. Although it is true that even very long defectscan be repaired with the left renal vein, tension in thevenous reconstruction should be avoided. In general,interest in our article, and hope this response has clarifiedsome of the matters raised.

    Disclosure Information: Nothing to disclose.

    Cross-Leg Flaps: PreferredAlternative To Free Flaps?

    Arash Momeni, MDPalo Alto, CA

    Rudolf F Buntic, MD, Gregory M Buncke, MDSan Francisco, CA

    We read with interest the article by Lu and colleagues1

    in the September 2013 issue about the authorspreference in using cross-leg flaps over microsurgicalreconstruction for the purpose of lower extremity recon-struction. Although the authors are to be congratulatedon their low postoperative complication rate, severalstatements made and conclusions drawn deserve furtherdiscussion. Despite the authors fairly extensive elabora-tion of why distant flaps should be preferred over freeflaps, it should be stressed that microsurgical recon-struction is and should be considered, the standard ofwhen reconstructing the SMV-PV, we strive to have itappear as close to perfect as possible, as it is a low-pressure system in an anatomic location prone tocompression. A long SMV-PV conduit sitting in thepancreatic bed is at risk of compression or thrombosisshould there be a pancreatic leak or fluid collection; incontrast, a mesocaval shunt is anatomically well awayand protected from this possibility.Lastly, for reconstruction with long conduits purely to

    restore the SMV-PV confluence, it is unclear whether theimportance of restoring complete flow to the PV throughthe SMV in a patient with an otherwise normal liver,whose PV remains patent via flow from the splenic vein(and left gastric vein), outweighs the risk of such longconduits when a simpler option of diverting the SMVinto the IVC exists. Equally important to emphasize,the caval end of the anastomosis of the mesocaval shunt(performed first) can be performed precisely withoutany time pressure for SMV and SMA occlusion, as thesevessels need not be occluded during this portion of theprocedure. Therefore, minimizing occlusion time andpotential for small bowel edema is another benefit of

  • adolescents. Ann Plast Surg 2000;45:595e600.3. Ducic I, Rao SS, Attinger CE. Outcomes of microvascular

    reconstruction of single-vessel lower extremities: limb

    Vol. 218, No. 2, February 2014 Letters 309care for managing complex traumatic lower extremitydefects due to clear advantages over the use of cross-leg flaps.The authors claim higher costs to be associated with

    microsurgery, but the increased procedural cost becomesirrelevant when considering the decreased length of hospi-tal stay associated with microsurgery. The patients in theauthors study underwent at least 2 operative proceduresin addition to remaining hospitalized for an average ofalmost 3 weeks. This is in contrast to a reported averagelength of hospitalization after microsurgical lower extrem-ity reconstruction of less than 2 weeks.2

    We disagree with the authors that a single-vesselextremity represents a contraindication for free flapreconstruction, particularly because a 100% flap survivalrate been reported in single-vessel lower extremities.3

    The authors understanding that an extremity receivingradiotherapy after tumor resection should be consid-ered a relative contraindication for microsurgical recon-struction is surprising; it is well known that well-vascularized tissue (ie, free flap) is more resistant tothe deleterious effects of radiotherapy. In fact, it wasthe advent of microsurgery that enabled limb preserva-tion in sarcoma patients.4

    The authors claim of greater safety associated withcross-leg flaps can only be regarded as unsubstantiated,particularly in light of a flap failure rate of as low as2.9% in patients undergoing post-traumatic microsurgicallower extremity reconstruction.5,6 Furthermore, it is inter-esting to note that the reference chosen by the authors tosupport their claim of a high rate of problems associ-ated with free flaps reported an overall incidence of flapfailure of merely 4.1%,7 which certainly comparesfavorably with the 3.3% flap loss rate reported by theauthors.The use of the contralateral distal lower extremity

    donor site in patients with poor distal wound healing,such as in a diabetic patient (see Fig. 6 from Lu et al1),is suboptimal. It presents the potential to iatrogenicallyintroduce a second problematic lower extremity wound,in addition to the one that is healed by marginallyperfused neovascularized tissue after flap division. Long-term (ie, when strict elevation is discontinued), this hasthe potential to result in 2 diabetic wounds.The authors understanding of the reconstructive

    ladder and the strict adherence to its rungs has to beconsidered obsolete in contemporary times. The edito-rial on the reconstructive elevator by Gottlieb andKrieger8 nicely points out the differences betweenmere wound closure and preservation or restoration offunction. It underscores the importance of a more crea-tive approach to reconstructive challenges as opposed toWe appreciate the response by Dr Arash Momeni and col-leagues and thank them for their concern about our articleand affirmation of our work.1 Given that it has been a com-mon practice in America that free flaps are chosen first forreconstructing the traumatic lower extremities, to whichcross-leg flaps are just taken as an alternative, we werenot surprised that Dr Momeni and colleagues raisedserious questions about our methodology in practice andsalvage versus amputation. J Reconstr Microsurg 2009;25:475e478.

    4. Momeni A, Kalash Z, Stark GB, Bannasch H. The use of theanterolateral thigh flap for microsurgical reconstruction of distalextremities after oncosurgical resection of soft-tissue sarcomas.J Plast Reconstr Aesthet Surg 2011;64:643e648.

    5. Sofiadellis F, Liu DS, Webb A, et al. Fasciocutaneous free flapsare more reliable than muscle free flaps in lower limb traumareconstruction: experience in a single trauma center.J Reconstr Microsurg 2012;28:333e340.

    6. Lowenberg DW, Buntic RF, Buncke GM, Parrett BM. Long-term results and costs of muscle flap coverage with Ilizarovbone transport in lower limb salvage. J Orthop Trauma 2013;27:576e581.

    7. Khouri RK, Cooley BC, Kunselman AR, et al. A prospectivestudy of microvascular free-flap surgery and outcome. PlastReconstr Surg 1998;102:711e721.

    8. Gottlieb LJ, Krieger LM. From the reconstructive ladder to thereconstructive elevator. Plast Reconstr Surg 1994;93:1503e1504.

    Disclosure Information: Nothing to disclose.

    Reply

    Lixuan Lu, MD, Xiaohai Zhu, MD,Antang Liu, MD, Hua Jiang, MD, Jie Zhang, MDShanghai, Chinaa simple sequential algorithm, which seems to be whatthe authors are advocating. It eludes us why one wouldchoose to subject patients to a period of suffering (ie,mandatory immobilization), and offer free flap recon-struction only when patients cannot bear the longhospital stay and the suffering of limb immobilization,when more superior modes of reconstruction areavailable.

    REFERENCES

    1. Lu L, Liu A, Zhu L, et al. Cross-leg flaps: our preferred alterna-tive to free flaps in the treatment of complex traumatic lowerextremity wounds. J Am Coll Surg 2013;217:461e471.

    2. Erdmann D, Lee B, Roberts CD, Levin LS. Management oflawnmower injuries to the lower extremity in children and

    Cross-Leg Flaps: Preferred Alternative To Free Flaps?References