Use of thirty latissimus dorsi flaps

Experiences with 30 latissimus dorsi flaps are described. Used either as a muscle flap, as a myocutaneous flap, or as an "island" of skin nourished by a subcutaneous pedicle of muscle and vessels, the flap has an excellent blood supply and is suitable for many repairs of defects of the chest wall.     

Experience with thirteen latissimus dorsi myocutaneous free flaps.

Subcutaneous "pocketing" is proposed as a simple and convenient method to nourish a denuded, replanted end of a finger, when the amputation is between the lunule and the DIP joint. The investigation of a laboratory model is presented, and our initial clinical experience is reported.     

Preconditioning of latissimus dorsi muscle flaps with monophosphoryl lipid a

The use of dynamic myoplasty to restore function to failing organs is an exciting new application of skeletal muscle flaps. A complication of large flap elevation that can compromise flap function is ischemia-induced necrosis; one approach to minimizing this is to pretreat tissues with ischemic preconditioning. The purpose of this study was to determine whether systemic administration of monophosphoryl lipid A, a drug known to mimic late-phase ischemic preconditioning in the heart, could reduce ischemia-induced necrosis in latissimus dorsi muscle flaps. Forty latissimus dorsi muscle flaps from 20 Sprague-Dawley rats were allocated into four groups. In group I (n = 10), flaps were not preconditioned and served as controls. In group II (n = 10), flaps received ischemic preconditioning with two 30-minute periods of ischemia interspersed by 10 minutes of reperfusion. In group III (n = 10), rats received an intravenous bolus of approximately 0.3 ml of monophosphoryl lipid A vehicle only. In group IV (n = 10), rats received an intravenous bolus of 450 microg/kg of monophosphoryl lipid A and vehicle. Twenty-four hours after treatment, all latissimus dorsi muscle flaps were elevated on a single neurovascular pedicle and subjected to 4 hours of ischemia. After 72 hours of reperfusion, latissimus dorsi muscles were harvested, weighed, stained with nitroblue tetrazolium, and assessed for percent necrosis using digitized images of muscle sections and computerized planimetry. The percent necrosis in ischemic preconditioning-treated flaps (group II) was significantly reduced by 57 percent (p < 0.05) compared with control flaps (group I). The percent necrosis in flaps treated with monophosphoryl lipid A (group IV) was significantly reduced by 58 percent (p < 0.05) compared with vehicle-control flaps (group III). There was no difference in mean percent necrosis between ischemic preconditioning (group II) and monophosphoryl lipid A-treated (group IV) flaps or between ischemic preconditioning-control (group I) and monophosphoryl lipid A vehicle-control (group III) flaps. Intravenous administration of systemic monophosphoryl lipid A mimics the late-phase protective effect of ischemic preconditioning in the authors' rat latissimus dorsi muscle flap model.     

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.     

Reducing the vascular delay period in latissimus dorsi muscle flaps for use in cardiomyoplasty

Although the mechanism by which vascular delay benefits skin flaps is not completely understood, this topic has been extensively studied and reported on in the literature. In contrast, little has been documented about the effects of vascular delay in skeletal muscle flaps. Recent animal studies tested the effectiveness of vascular delay to enhance latissimus dorsi muscle flap viability for use in cardiomyoplasty and found that it prevented distal flap necrosis. However, these studies did not define the optimal time period necessary to achieve this beneficial effect. The purpose of this study was to determine how many days of "delay" can elicit the beneficial effects of vascular delay on latissimus dorsi muscle flaps. To accomplish this, 90 latissimus dorsi muscles of 45 male Sprague-Dawley rats were randomly subjected to vascular delay on one side or a sham procedure on the other. After predetermined delay periods (0, 3, 7, 10, and 14 days) or a sham procedure, all latissimus dorsi muscles were elevated as single pedicled flaps based only on their thoracodorsal neurovascular pedicle. Latissimus dorsi muscle perfusion was measured using a Laser Doppler Perfusion Imager just before and immediately after flap elevation. The muscles were then returned to their original vascular beds, isolated from adjacent tissue with Silastic film, sutured into place to maintain their original size and shape, and left there for 5 days. After 5 days, the latissimus dorsi muscle flaps were dissected free, scanned again (Laser Doppler Perfusion Imager-perfusion measurements), and the area of distal necrosis was measured using digitized planimetry of magnified images. The authors' results showed that delay periods of 3, 7, 10, and 14 days significantly increased (p < 0.05) blood perfusion and decreased (p < 0.05) distal flap necrosis when compared with sham controls. On the basis of these findings, the authors conclude that in their rat latissimus dorsi muscle flap model the beneficial effects of vascular delay are present as early as 3 days. If these findings also hold true in humans, they could be useful in cardiomyoplasty by allowing surgeons to shorten the amount of time between the vascular delay procedure and the cardiomyoplasty procedure in these very sick patients.     

The free latissimus dorsi myocutaneous flap.

The general anatomy and the detailed vascular anatomy of the latissimus dorsi myocutaneous flap is described, and its use as a free flap is illustrated. The speed and ease with which it can be raised, its long vascular pedicle, the large diameter of the donor vessels, and the potentially large size of the flap are emphasized.     

Widely split latissimus dorsi muscle flaps for reconstruction of long soft-tissue defects in lower extremities

Although the latissimus dorsi is one of the largest and longest muscles in the human body, it is still sometimes inadequate for reconstruction of a soft-tissue defect of extensive length and dimension. Eight patients with such lower limb defects were treated with latissimus dorsi muscles split into two hemiflaps sequentially linked, one after the other like a chain. Six transfers were completely successful, one required reexploration for arterial occlusion, and two hemiflaps had a partial loss that could be managed by touching up the skin graft. The average split sequential-link muscle was 42 cm in length. Although two patients had a partial loss, we consider that the widely split single latissimus dorsi muscle can still be used reliably to reconstruct a long slender defect, or two separate, longitudinally located, medium-sized defects in the same leg.     

Vascular endothelial growth factor expression in pig latissimus dorsi myocutaneous flaps after ischemia reperfusion injury

Exogenous administration of vascular endothelial growth factor (VEGF) improves long-term viability of myocutaneous flaps. However, endogenous expression of this substance in flaps following ischemia-reperfusion injury has not been reported previously. Endogenous production of VEGF was measured in myocutaneous pig latissimus dorsi flaps after ischemia-reperfusion injury. Latissimus dorsi myocutaneous flaps (15 x 10 cm) were simultaneously elevated bilaterally in six Yorkshire-type male pigs (25 kg). Before elevation, three flap zones (5 x 10 cm) were marked according to their distance from the vascular pedicle. After isolation of the vascular pedicle, ischemia-reperfusion injury was induced in one flap by occlusion of the thoracodorsal artery and vein for 4 hours, followed by 2 hours of reperfusion. The contralateral flap served as a control. Perfusion in each zone was monitored by laser Doppler flowmetry at baseline, during ischemia, and during reperfusion. At the end of the protocol, skin and muscle biopsies of each flap zone and adjacent tissues were obtained for later determination of VEGF protein levels. VEGF concentrations were quantified using the Quantikine human VEGF immunoassay. Skin perfusion was similar among all flap zones before surgery. Flow fell in all flaps immediately after flap elevation. After 4 hours of ischemia, blood flow in the ischemic flaps was significantly decreased (p < 0.05) compared with nonischemic control flaps. After 2 hours of reperfusion, flow in ischemic flap skin recovered to levels similar to those in control flaps. VEGF protein concentrations in muscle tissue exceeded concentrations in skin and decreased from zones 2 to 3 in control and ischemic flaps. No significant differences in VEGF concentrations between ischemic and control muscle zones were observed. However, the concentration of VEGF in all muscle zones was significantly higher (p < 0.05) than muscle adjacent to the flap. Concentrations in skin zones 1 and 2 were significantly higher (p < 0.05) in ischemic flaps than in control flaps, but levels in zone 3 (most ischemic flaps) showed no significant difference.     

A new experimental model for myocutaneous flaps: latissimus dorsi of the rabbit--an anatomic study

A new experimental model, the latissimus dorsi flap of the rabbit, was studied. This was found to be a relatively inexpensive research model. Its use is advocated for composite tissue transfer as transposition, island, or free myocutaneous flaps.     

The tailored latissimus dorsi free flap

A technique is described for dissection of the latissimus dorsi free flap which yields musculocutaneous cover accurately tailored to the primary defect. It involves exposure high into the axilla, early transverse incision of the muscle to enhance visualization of the pedicle, and transection of the muscle close to the point at which the thoracodorsal artery enters. This last step eliminates the bulky portion of the muscle between this point of vascular supply and its insertion.     

The reduced latissimus dorsi musculocutaneous flap

This report introduces a new device among latissimus dorsi flaps: the reduced latissimus dorsi musculocutaneous flap. This flap consists of a proximal musculocutaneous unit and a distal, thin fasciocutaneous unit (the reduced portion). The former unit carries a reliable blood supply from the thoracodorsal artery and is able to cover deeper recipient defects, while the latter provides a well-contoured reconstruction of the defect. If needed, an extended portion and/or a thin cutaneous flap can be carried along with the flap according to the defect. In our clinic, we have so far used four pedicled and one free reduced latissimus dorsi musculocutaneous flap in the repair of a variety of defects. All flaps survived, and satisfactory contour of the recipient site was achieved in each case. These clinical experiences clarify that a reduced portion 10 cm in length can be safely carried, and it is suggested that survival of this flap does not depend on its width-to-length ratio.     

Tissue carbon dioxide tension: a putative specific indicator of ischemia in porcine latissimus dorsi flaps

Free flap surgical procedures are technically challenging, and anastomosis failure may lead to arterial or venous occlusion and flap necrosis. To improve myocutaneous flap survival rates, more reliable methods to detect ischemia are needed. On the basis of theoretical considerations, carbon dioxide tension, reflecting intracellular acidosis, may be suitable indicators of early ischemia. It was hypothesized that tissue carbon dioxide tension increased rapidly when metabolism became anaerobic and would be correlated with acute venoarterial differences in lactate levels, potassium levels, and acid-base parameters. Because metabolic disturbances have been observed to be less pronounced in flaps with venous occlusion, it was hypothesized that tissue carbon dioxide tension and venoarterial differences in lactate and potassium levels and acid-base parameters would increase less during venous occlusion than during arterial occlusion. In 14 pigs, latissimus dorsi myocutaneous flaps were surgically isolated, exposed to acute ischemia for 150 minutes with complete arterial occlusion (seven subjects) or venous occlusion (seven subjects), and reperfused for 30 minutes. After arterial occlusion, pedicle blood flow decreased immediately to less than 10 percent of baseline flow. Blood flow decreased more slowly after venous occlusion but within 3 minutes reached almost the same low levels as observed during arterial occlusion. Venous oxygen saturation decreased from approximately 70 percent to approximately 20 percent, whereas oxygen uptake was almost arrested. Tissue carbon dioxide tension increased to two times baseline values in both groups (p < 0.01). The venoarterial differences in carbon dioxide tension, pH, base excess, glucose levels, lactate levels, and potassium levels increased significantly (p < 0.01). Tissue carbon dioxide tension measured during the occlusion period were closely correlated with venoarterial differences in pH, base excess, glucose levels, lactate levels, and potassium levels (median r2, 0.67 to 0.92). After termination of arterial or venous occlusion, more pronounced hyperemia was observed in the arterial occlusion group than in the venous occlusion group (p < 0.05). Oxygen uptake (p < 0.05) and venoarterial differences in lactate and potassium levels (p < 0.05) were significantly more pronounced in the arterial occlusion group. In the venous occlusion group, with less pronounced hyperemia, venoarterial differences in acid-base parameters remained significantly different from baseline values before occlusion (p < 0.01). The data indicate that tissue carbon dioxide tension can be used to detect anaerobic metabolism, caused by arterial or venous occlusion, in myocutaneous flaps. The correlations between carbon dioxide tension and venoarterial differences in acid-base parameters were excellent. Because carbon dioxide tension can be measured continuously in real time, such measurements are more likely to represent a clinically useful parameter than are venoarterial differences.     

Lumbar hernia after latissimus dorsi flap

The authors present what they believe to be the first recorded case of a lumbar hernia following latissimus dorsi myocutaneous flap procedure. The authors discuss the diagnosis by physical examination and x-ray confirmation, pointing out the importance of not mistaking the hernia for a seroma. Suggestions for avoiding the problem are given, relating primarily to preservation of the fascia underlying the distal latissimus aponeurosis.     

Simultaneous bilateral breast reconstruction using latissimus dorsi myocutaneous flaps: a retrospective review of an institutional experience

A single institution's experience in the simultaneous reconstruction of both breasts using bilateral latissimus dorsi myocutaneous flaps is presented. The procedure was performed on 24 patients by the attending staff of the department of plastic surgery at St. Joseph Hospital in Houston, Texas, between 1979 and 1999. Of the 24 patients reviewed, six had immediate reconstructions, 13 had delayed primary reconstructions, and five had secondary reconstructions of failed or unsatisfactory primary procedures. In the group with delayed reconstructions, the average time between mastectomy and reconstruction was 46.4 months, with a range from 7 days to 21 years. The operative method, results, and outcomes of our experience in these patients is presented.