Pectoralis Major Muscle Flap Utilization in Salvage Esophagectomy Including Great Vessel Resection Reconstructed by Prosthetic Grafts.

BACKGROUND: Salvage surgery is a therapeutic option for recurrent or residual esophageal cancer after definitive chemoradiation therapy. This report aimed to describe the procedure of reconstruction after salvage esophagectomy involving great vessel resection using prosthetic grafts, a pectoralis major muscle (PM) flap, and free jejunal transfer, if required. To the best of our knowledge, no previous report has described the reconstruction of the defect after combined esophageal and great vessel resection. PATIENTS AND METHODS: From January 2017 to December 2022, 4 patients underwent salvage esophagectomy with excision of the great vessels and reconstruction with prosthetic grafts, as well as a PM flap placement in a single center. We retrospectively investigated the patients' clinical data. The patients were all men, with a median age of 70 (range, 67-77) years. Regarding neoadjuvant therapy, 2 patients received chemoradiation therapy, 1 patient received radiotherapy only due to drug-induced pneumonia, and 1 patient received chemotherapy with adjuvant radiotherapy. RESULTS: Alimentary tract reconstruction was performed by free jejunal transfer in 2 cases, direct suture in 1 case, and stomach roll in 1 case. In all cases, a vascular bypass was established before tumor resection. We created mediastinal tracheostoma in 2 cases. A PM flap was inserted to cover the prosthetic grafts and approximate the tracheal mucosa. With regard to major complications, leakage from the jejunal esophageal anastomotic site was observed in 2 cases. The leakage improved with conservative treatment without graft removal or replacement in both cases. CONCLUSIONS: In cases of locally recurrent or residual tumors after definitive chemoradiation therapy, salvage esophagectomy along with great vessel resection, followed by reconstruction using prosthetic grafts, PM flaps, and free jejunal transfer, if necessary, is a useful option.

The Ischemic Tolerance up to Four Hours of Free Jejunum Flap: A Retrospective Cohort Study.

BACKGROUND: While free jejunum transfer (FJT) following total pharyngo-laryngo-esophagectomy (TPLE) is a reliable reconstruction technique, the jejunum flap is viewed as more susceptible to ischemia than a standard free flap. Animal studies have indicated that the jejunum can tolerate ischemia for as little as 2 to 3 hours. Clinical studies also reported increased complications after the FJT with more than 3 hours of ischemia. Traditionally, our institution has carried out FJT with an initial intestinal anastomosis, followed by a vascular anastomosis, which often results in extended jejunal ischemia time. In this study, we retrospectively examined the actual tolerance of the jejunum to ischemia, considering perioperative complications and postoperative dysphagia. METHODS: We retrospectively studied 402 consecutive cases involving TPLE + FJT. Patients were divided into five groups based on jejunum ischemia time (∼119 minutes, 120∼149 minutes, 150∼179 minutes, 180∼209 minutes, 210 minutes∼), with each variable and result item compared between the groups. Univariate and multivariate analyses were conducted to identify independent factors influencing the four results: three perioperative complications (pedicle thrombosis, anastomotic leak, surgical site infection) and dysphagia at 6 months postoperatively. RESULTS: The mean jejunal ischemia time was 164.6 ± 28.4 (90-259) minutes. When comparing groups divided by jejunal ischemia time, we found no significant differences in overall outcomes or complications. Our multivariate analyses indicated that jejunal ischemia time did not impact the three perioperative complications and postoperative dysphagia. CONCLUSION: In TPLE + FJT, a jejunal ischemia time of up to 4 hours had no effect on perioperative complications or postoperative dysphagia. The TPLE + FJT technique, involving a jejunal anastomosis first followed by vascular anastomosis, benefits from an easier jejunal anastomosis but suffers from a longer jejunal ischemia time. However, we found that ischemia time does not pose significant problems, although we have not evaluated the effects of jejunal ischemia extending beyond 4 hours.

Soft Tissue Reconstruction Using the Free Forearm Fillet Flap in the Salvage of Forequarter Amputations for Recurrent Sarcoma: A Report of 2 Cases.

ABSTRACT: Reconstruction after radical forequarter amputation for recurrent proximal extremity sarcoma is challenging because the defect is significant, and the axillary or subclavian vessels are resected with the tumor, indicating that the pedicle of nearby flaps is often cut off. Free flaps are commonly used to cover the defect, but the donor site morbidity is problematic. Another problem with resecting the axillary or subclavian vessels is difficulty obtaining recipient vessels with matching calibers for another free flap. The authors presented 2 cases that successfully solved all these problems by covering the defects by the forearm fillet flaps.The forearm fillet flap has the advantage of using a portion that is usually discarded, so there is no donor site morbidity. Moreover, using the brachial artery as the pedicle of the flap allows the anastomosis to the stump of the resected axillary or subclavian artery because differences in caliber are slight.The use of the forearm fillet flaps has been reported less frequently than the fillet flaps in the lower extremities, and most cases are posttraumatic. In cases of trauma, complications are reported to occur in about 1 in 4 patients, but in cases after tumor resection, ischemic time can be controlled, and there are no risks of contamination or unnoticed forearm damage, so more stable results can be expected as in this report.Using the free flap from the distal portion of the resected upper limb, especially in cases with a short prognosis, is a viable option that effectively minimizes damage to the donor site and maintains quality of life.

Free Flap Reconstruction of Oncologic Gluteal Defects.

ABSTRACT: A number of studies have already examined gluteal reconstruction with free flaps. Thus, the aim of this study was to investigate the reliability of free flap reconstruction for oncologic gluteal defects. This retrospective cohort study included 23 patients who underwent immediate soft tissue reconstruction for an oncologic gluteal defect. Fifteen patients underwent reconstruction with a free flap and 8 with a regional flap. The postoperative results were compared between the free and regional flaps. In the free flap group, the latissimus dorsi musculocutaneous flap was used in 12 patients, the thoracodorsal artery perforator flap in 2 patients, and the anterolateral thigh flap in 1 patient. Recipient vessels were the inferior gluteal vessels or their branches in 8 patients and the superior gluteal vessels or their branches in 7 patients. All flaps have fully survived in both groups without vascular compromise. Dehiscence of the gluteal wound tended to be more common in the regional flap group; however, the difference between the groups was not statistically significant. The use of free flap reconstruction for large oncologic defects in the gluteal region is a feasible and reliable option. Tension-free wound closure and simplified suture lines can provide reliable wound coverage irrespective of the postoperative patient's position or movement. Because of the risk of postoperative compression on the vascular pedicle, selecting the appropriate recipient vessel and type of microvascular anastomosis is key for the success of free flap transfer in this region.

Combined use of ipsilateral latissimus dorsi flap and anterolateral thigh flap to reconstruct extensive trunk defects.

Reconstruction of a full-thickness trunk defect is challenging because of the complex nature of such defects, which include the chest wall, abdominal wall, and diaphragm. We herein describe three patients in whom extensive trunk defects after sarcoma resection were reconstructed with a latissimus dorsi flap and an anterolateral thigh flap. In two patients, the defect included both the chest wall and the abdominal wall. The other patient had an extensive full-thickness chest wall defect. The size of the anterolateral thigh flap for each patient was 34 × 10 cm, 26 × 15 cm, and 23 × 5 cm, respectively. Although one patient required take-back for additional venous drainage, all wounds healed with no other complications. No respiratory dysfunction or abdominal wall hernia occurred in any patients. The combined use of a latissimus dorsi flap and an anterolateral thigh flap may provide reliable coverage of an extensive trunk defect and robust support of the chest and abdominal walls. Additionally, the availability of a two-team approach without a positional change makes this combination a versatile reconstructive option.

Large-to-Small End-to-Side Venous Anastomosis in Free Flap Transfer.

BACKGROUND: Vessel size discrepancy is one of the major risk factors for anastomotic failure in free flap transfer. The situation becomes challenging for reconstructive microsurgeons when the recipient vein is much smaller than the flap vein. We investigated the feasibility of large-to-small end-to-side venous anastomosis for such cases. MATERIALS AND METHODS: The subjects were 16 consecutive patients who underwent a free flap transfer for oncologic defects with a large-to-small end-to-side venous anastomosis. The larger flap vein was anastomosed to the side slit of the smaller recipient vein under an operating microscope. Surgical details and postoperative outcome were investigated retrospectively. RESULTS: An anterolateral thigh flap was used in five patients, a superficial inferior epigastric artery flap in four, a thoracodorsal artery perforator flap in three, and a latissimus dorsi musculocutaneous flap and a fibular osteocutaneous flap in two patients each. The internal mammary vein and the anterior tibial vein were most frequently used as a recipient vein (four patients each), followed by the deep inferior epigastric vein (three patients). The extent of vessel size discrepancy ranged from 1.3- to 3.3-fold, and the mean discrepancy was 1.9-fold. No anastomotic failure occurred postoperatively, and the flap survived in all patients. CONCLUSIONS: Large-to-small end-to-side venous anastomosis can be a versatile option when only a small vein is available as a recipient vein. Internal mammary, deep inferior epigastric, and anterior tibial veins are good candidates for this technique.

The use of lower abdominal perforator flaps in soft-tissue reconstruction after sarcoma resection.

BACKGROUND: Historically, conventional musculocutaneous flaps have been commonly used for reconstruction after soft tissue sarcoma resection, and the use of lower abdominal perforator flaps has not been popular. This report examined the current role of lower abdominal perforator flaps in sarcoma treatment. METHODS: We reviewed the outcomes of 14 patients (mean age: 46.3 years, range: 18-79 years) who underwent immediate reconstruction with a deep inferior epigastric artery perforator (DIEP) flap or a superficial inferior epigastric artery (SIEA) flap after sarcoma resection. The defects ranged in size from 7 × 6 cm2 to 25 × 22 cm2 (mean: 16.5 × 12.1 cm2 ). An oblique design was used for pedicled DIEP flaps and a transverse design for free DIEP flaps. RESULTS: Free SIEA flaps were used in six patients, pedicled DIEP flaps in five, and free DIEP flaps in three. The flaps ranged in size from 13 × 8 cm2 to 36 × 12.5 cm2 (mean: 23.1 × 9.2 cm2 ). All DIEP flaps except one were harvested based on one dominant perforator. All flaps survived without vascular compromise. Surgical site infection and seroma occurred at the recipient site in one patient each. No donor-site complications occurred. CONCLUSIONS: Lower abdominal perforator flaps can serve as a versatile donor site for reconstruction after sarcoma resection.

Free latissimus dorsi musculocutaneous flap for external hemipelvectomy reconstruction.

INTRODUCTION: External hemipelvectomy is one of the most extensive surgical procedures for locally advanced pelvic tumors. Stump coverage with the local tissues can be difficult in recurrent cases. Herein, we report our experience with immediate stump coverage using a free latissimus dorsi musculocutaneous (LDMC) flap after external hemipelvectomy for recurrent pelvic malignancies. METHODS: Six patients underwent external hemipelvectomy and immediate reconstruction using a free LDMC flap between November 2012 and June 2017. The mean age of the patients was 65 years (range: 63-69 years). The primary tumors were myxoid liposarcoma, chondrosarcoma, osteosarcoma, squamous cell carcinoma, and pleomorphic liposarcoma. A free LDMC flap was harvested from the ipsilateral back and transferred to the defect. When an intercostal nerve was found at the recipient site, the thoracodorsal nerve was coaptated with the intercostal nerve to reinnervate the muscle. RESULTS: The mean flap size was 23 × 10 cm and the range was 20 × 8-27 × 13.5 cm. The contralateral deep inferior epigastric vessels were used as recipient vessels in all patients. Thoracodorsal-intercostal nerve coaptation was performed in 2 patients. The flap survived in all patients. Three patients had complications of abscess formation. No patient developed postoperative hernia. CONCLUSION: Although it is challenging to do reconstruction after external hemipelvectomy, a free LDMC flap has several advantages, including a large coverage area, stability of circulation, ease of elevation, and preservation of the strength of the remaining abdominal wall. Technical tips for selecting anastomosis vessels are important and nerve coaptation could be effective.

Comparison of Donor Site Drainage Duration and Seroma Rate Between Latissimus Dorsi Musculocutaneous Flaps and Thoracodorsal Artery Perforator Flaps.

INTRODUCTION: Donor site seroma formation and prolonged drainage duration are common complications of using latissimus dorsi musculocutaneous (LDMC) flaps. The present retrospective study aimed to investigate the effect of types of back flap harvest on drainage duration and seroma formation rates. METHODS: Adult patients (n = 155) who underwent reconstruction with a latissimus dorsi flap from January 2010 to October 2015 were included in the study, of which 54 patients underwent breast reconstruction with a pedicled LDMC flap (LD breast group), 80 patients underwent an LDMC flap transfer for purposes other than breast reconstruction (LD nonbreast group), and 21 patients underwent soft tissue reconstruction with a thoracodorsal artery perforator (TAP) flap (TAP group). Flap size, drainage durations, and seroma formation rates at donor sites were compared among the 3 groups. RESULTS: Flap sizes significantly differed between the LD nonbreast group (median value, 185.5 cm) and the other 2 groups (119 cm in the LD breast group. 127.5 cm in the TAP group), with no significant difference observed between the LD breast and TAP groups. The mean drainage duration was 11.6 days for the LD breast group. 9.82 days for the LD nonbreast group, and 4.81 days for the TAP group. Drainage durations significantly differed among the groups. Seroma formation rate of the LD breast group (42.6%) was significantly higher than those of the other groups. CONCLUSIONS: The type of back flap harvest used significantly affected drainage duration and seroma formation rate in the present study. Lumbar fat extension with the use of a LDMC flap for breast reconstruction may lead to seroma formation. Thoracodorsal artery perforator flaps are associated with minimal risks of seroma formation and significantly shortened drainage duration compared with LDMC flaps.

The Superior Rectal Artery as a Recipient Vessel for Free Flap Transfer After Partial Sacrectomy in Patients With Chordoma.

Free flaps have rarely been used to reconstruct lumbosacral defects, primarily because of the lack of suitable recipient vessels in this region. We propose the novel use of the superior rectal artery as a recipient vessel for free flap transfer after partial or total sacrectomy. We transferred free flow-through latissimus dorsi musculocutaneous flaps, with the superior rectal vessels as recipient vessels, to reconstruct defects after partial sacrectomy in 2 patients with sacral chordoma. The flaps survived completely, and the wounds healed uneventfully in both patients. The superior rectal artery is easier to dissect and anastomose than are gluteal vessels and is less affected by patients' postoperative postural change than are extraperitoneal vessels. We believe that the superior rectal artery is a versatile recipient vessel for free flap transfer to reconstruct sacrectomy defects.

Scapula harvest in the supine position for immediate mandibular reconstruction.

PURPOSE: The scapula is the second most popular donor site for mandibular reconstruction after the fibula. Scapula harvest is generally performed in the lateral decubitus position and the requirement of positional changes hamper the widespread use of the scapula. This study compared scapula harvest for immediate mandibular reconstruction between the supine and lateral decubitus positions. METHODS: We reviewed the outcomes of 16 patients who underwent segmental mandibulectomy and immediate reconstruction of the scapula based on the angular branch of the thoracodorsal artery. The scapula was harvested in the lateral decubitus (lateral decubitus group) or supine position (supine group) in eight patients each. Several perioperative parameters were compared between the two groups. RESULTS: One scapula was lost because of inadvertent injury of the angular branch in the supine group. The operative time was significantly shorter in the supine group than in the lateral decubitus group. CONCLUSION: Harvesting of the scapula in the supine position is a feasible option for immediate mandibular reconstruction. Although deep anatomic knowledge and technical expertise are necessary, this strategy can eliminate positional change and significantly reduce the operative time.

Zygomatico-orbital artery as a recipient vessel for microsurgical head and neck reconstruction.

The selection of recipient vessels in head and neck reconstruction is one of the key factors influencing its difficulty and outcome. We report a case of a microsurgical scalp reconstruction using the zygomatico-orbital artery as a recipient vessel.A 71-year-old woman had intractable skin ulcers on her head after neurosurgeries. Computed tomography angiography findings showed that the superficial temporal artery was obstructed and that the zygomatico-orbital artery ran forward and upward. She underwent scalp reconstruction using a free anterior lateral thigh flap. The zygomatico-orbital artery was dissected distally, cut, and turned over cranially. The diameter of the zygomatico-orbital artery was 1.2 mm. The blood flow through the zygomatico-orbital artery was sufficient. The thinned scalp area was excised, and some of the titanium devices and infectious tissues were removed. An anterior lateral thigh flap measuring 20 × 9 cm was harvested and transferred to the defect in the head. The discrepancy in calibers was within double, and the zygomatico-orbital artery fit the descending branch of the lateral circumflex femoral artery. The flap was transferred successfully.The zygomatico-orbital artery is one of the branches from the external carotid artery and supports the suprazygomatic territory. The zygomatico-orbital artery is present in 78% to 92% of people and originates from the superficial temporal artery and sometimes from the frontal branch of superficial temporal artery. The mean diameter of the zygomatico-orbital artery at origin is reported to be 1.20 mm. The zygomatico-orbital artery is another option as a recipient vessel in head and neck reconstruction.

Outcomes of Sling Procedure Using a Free Vascularized Fibular Graft After Resection of the Proximal Humerus.

Background: The proximal humerus is a common site for both primary and metastatic bone tumors. Although various methods have been developed for reconstruction following resection of the proximal humerus, a consensus on which technique is best has not been established. We focused on the sling procedure using a free vascularized fibular graft (FVFG) and conducted what we believe to be the largest retrospective study of patients to undergo this surgery to date. Methods: We retrospectively reviewed the data of 19 patients who underwent the sling procedure with use of an FVFG at our hospital between 1998 and 2022. The median age was 20 years, and the median follow-up duration was 63.1 months. Surgical data, oncological outcomes, the postoperative course, complications, and functional outcomes as measured with use of the Musculoskeletal Tumor Society (MSTS) score were thoroughly reviewed. Results: The median operative duration was 555 minutes, and the median blood loss was 374 mL. The median length of the bone defect was 17.0 cm, and the median length of the graft was 20.0 cm. With respect to oncological outcomes, 9 patients were continuously disease-free, 9 patients had no evidence of disease, and 1 patient was alive with disease. Bone union was present in 13 of the 17 patients for whom it was evaluable. The median time to bone union was 4 months. Graft growth was observed in 2 pediatric patients. Postoperative fracture was a major complication at the recipient site. The incidence of pseudarthrosis significantly increased when the FVFG could not be inserted into the remaining humeral bone or was split in half (p = 0.002). Although a few patients demonstrated peroneal nerve palsy at the donor site, the symptom was temporary. The overall functional outcome was favorable, with an average MSTS score of 66.9%. Conclusions: The sling procedure demonstrated a low complication rate and a favorable functional outcome overall. Therefore, we believe that this procedure is a useful reconstruction method for patients in a broad age range who have a wide defect of the proximal humerus. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Superficial Temporal Vein and Alternative Middle Temporal Vein as Recipient Veins for Free-flap Reconstruction.

The superficial and middle temporal veins (STV and MTV) have been used as recipient veins for free-flap reconstruction; however, the STV is sometimes small and cannot be used, while the MTV is not fully recognized or utilized as a recipient vein. The purpose of the present study was to evaluate the reliability of the STV/MTV as recipient veins and to verify the utility and availability of the MTV by comparing the two veins. Thirty-five consecutive cases of free-flap reconstruction utilizing recipient vessels in the temporal region were retrospectively reviewed. Regarding recipient veins, the STV was the only option in the first 18 cases; the MTV was included among the options in the latter 17 cases. The calibers of the STV/MTV were evaluated at two level points (1: zygomatic arch, 2: palpebral fissure) using the results of preoperative dynamic-enhanced computed tomography (CT). Two cases of severe venous congestion were identified among the first 18 patients. After the adoption of the MTV, the MTV was used in 10 of the 17 cases, and no vascular complication occurred. On CT imaging evaluation, the caliber of the MTV (Point 2) (2.94 ± 0.55 mm) was significantly larger than the calibers of the STV (Point 1) (2.40 ± 0.48 mm) and MTV (Point 1) (2.49 ± 0.43 mm) (both P < 0.001). Regarding the recipient veins in the temporal area, the MTV can offer an option with a larger caliber or for additional venous anastomosis when the condition of the STV is inadequate.

Crescent-shaped skin paddle for a fibular flap: Avoiding skin grafting at the donor site.

A fibular osteocutaneous flap is the mainstay of oromandibular reconstruction. This report aimed to present a crescent-shaped skin paddle, a novel fibular skin paddle designed to achieve both sufficient intraoral lining and primary closure of the donor site. A 3-5-cm-wide crescent-shaped skin paddle was harvested according to the locations of the distal septocutaneous perforators on preoperative color Doppler sonography. This narrow skin paddle fits well morphologically into the mucosal defect, enabling a reliable intraoral lining. This advantage becomes more evident when the mandibular defect crosses the midline or extends posteriorly to the maxillary tuberosity as the shape of the mucosal defect becomes arcuate. Primary closure of the donor site is easier to achieve because the required width of the crescent-shaped skin paddle is minimized. This method reduces donor-site morbidity associated with skin grafting while ensuring safe intraoral closure with a fibular osteocutaneous flap.

A Quantitative Evaluation of the Flow-Increasing Effect of Flow-Through Arterial Anastomosis in the Vascular Pedicle of Free Flaps: A Prospective Clinical Before-and-After Study.

BACKGROUND: The clinical application of flow-through anastomosis has been reported in various studies; however, no studies have quantitatively evaluated and compared the actual hemodynamics in flow-through anastomosis and end-to-end anastomosis. This study quantitatively evaluated the blood inflow (volumetric flow rate) and vascular resistance (pulsatility index) of flow-through arterial anastomosis using an ultrasonic flowmeter, and compared these values with those of end-to-end anastomosis in actual clinical settings. In addition, factors affecting the outcomes have also been examined. METHODS: Twenty-eight patients who underwent free flap reconstruction after tumor resection were subjected to flow-through arterial anastomosis and flow examination. First, in the end-to-end state, the proximal anastomotic site was measured. This was followed by the opening of the distal arterial clamp, and measurement was then continued (in the flow-through state). RESULTS: In flow-through arterial anastomosis compared with end-to-end anastomosis, the volumetric flow rate was significantly increased (18.9 ± 14.1 ml/minute versus 6.0 ± 6.3 ml/minute) and the pulsatility index was significantly decreased (5.2 ± 3.7 versus 13.6 ± 10.2), when comparing paired data. Multiple regression analyses revealed that a perforator flap (versus a musculocutaneous flap) was independently associated with both reduced volumetric flow rate and increased pulsatility index in end-to-end anastomosis, and that hypertension was independently associated with an increased pulsatility index in end-to-end anastomosis. However, no factors in flow-through anastomosis were significantly associated with those values. CONCLUSION: In terms of blood flow and vascular resistance, flow-through arterial anastomosis was considered to have promising quantitative effects and should be performed when the conditions of both the donor and recipient vessels meet the requirements. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Chronological flap volume and distribution changes after reconstruction of total maxillectomy defect using a rectus abdominis myocutaneous flap.

BACKGROUND/PURPOSE: After total or subtotal maxillectomy, reconstruction using a free rectus abdominis myocutaneous (RAMC) flap is a fundamental and useful option. The purpose of the present study was to clarify the degree of flap volume change and volume distribution change with time after total or subtotal maxillectomy and free RAMC flap reconstruction and to examine the factors affecting the results. METHODS: A total of 20 patients who underwent total or subtotal maxillectomy with free RAMC flap reconstruction were examined, and the flap volume change rate (volume at final evaluation [POD 181-360] / volume at initial evaluation [POD 5-30]) was investigated using the results of imaging tests. Moreover, the flap was divided into four blocks (A-D) in the cranio-caudal direction, and the volume change of each block was individually analyzed. RESULTS: The overall volume change rate of fat/muscle/total was 0.84 ± 0.21/0.36 ± 0.08/0.67 ± 0.15, at the mean follow-up period of 309±35 days after the operation. The multiple regression analysis revealed that weight loss (for fat), postoperative RT (for fat and muscle), and young age (for muscle) were independently associated with flap volume loss. The results also indicated that the fat volume was stable, whereas the muscle volume decreased to <40% over time, assuming there were no influencing factors. Regarding flap volume distribution change, the fat volume tended to gather toward the central-cranial direction, while the muscle volume gathered toward the cranial direction, and total flap volume gathered toward the central direction.

The concept of "whole perforator system" in the lateral thoracic region for latissimus dorsi muscle-preserving large flaps: An anatomical study and case series.

BACKGROUND: Previous studies have reported on the abundant cutaneous perforating blood vessels around the latissimus dorsi (LD) lateral border, such as a thoracodorsal artery perforator (TDAP) of septocutaneous type (TDAP-sc) and muscle-perforating type (TDAP-mp), or the lateral thoracic artery perforator (LTAP). These perforators have been clinically utilized for flap elevation; however, there have been few studies that accurately examined all the cutaneous perforators (TDAP-sc, TDAP-mp, LTAP) around the LD lateral border. Here, we propose a new "whole perforator system" (WPS) concept in the lateral thoracic region and a methodology that enables elevating large flaps with reliable perfusion in a muscle-preserving manner. METHODS: We first performed an anatomical study that verified the number and perforating points of all perforators around the LD lateral border using the results of dynamic contrast-enhanced magnetic resonance imaging of patients with breast cancer. Following the anatomical evaluation, we performed large muscle-preserving flap transfer that contained all of the perforators around the LD lateral border in an actual clinical setting. RESULTS: A total of 175 latissimus dorsi from 98 patients were included. The mean number of perforators (TDAP-sc + TDAP-mp + LTAP) per side was 4.51±1.44 (2-9); TDAP-sc was present in 57.1% (100/175) of cases, and TDAP-mp in 76.6% (134/175); the TDAP total prevalence rate (TDAP-sc + TDAP-mp) was 96.0% (168/175). The LTAP existence rate was 94.3% (165/175). Distance from the axillary artery to the TDAP-sc was 148.7±56.3 mm, which was significantly proximal to the TDAP-mp (183.8±54.2 mm) and LTAP (172.2±81.3 mm). CONCLUSION: The lateral thoracic region has an abundant cutaneous perforator system derived from the descending branch of the thoracodorsal and lateral thoracic arteries. Clinical application of the lateral thoracic WPS flap is promising, with a large survival area even with muscle-preserving procedures and requiring a relatively simple procedure.

Boomerang-shaped Lateral-to-back Flap Utilizing Multiple Thoracodorsal Artery Perforators around the Lateral Border of Latissimus Dorsi Muscle for Reconstruction of Large Circular Defect.

We herein report the successful reconstruction of an extensive circular skin defect of the elbow region using a boomerang-shaped lateral-to-back muscle-sparing latissimus dorsi myocutanous flap utilizing multiple thoracodorsal artery perforators around the lateral border of the latissimus dorsi. The patient was a 74-year-old woman who presented with pleomorphic sarcoma in the left elbow region. The tumor was extensively resected and the skin defect was 13.5 × 12 cm. The boomerang-shaped lateral-to-back muscle-sparing-latissimus dorsi myocutanous flap was transferred as a free flap with the pedicle vessels anastomosed to the brachial artery and vein. The 2 wings of the boomerang were bent in a U shape to completely cover the skin defect. The donor site was closed primarily. This flap can be a versatile option for reconstructing extensive skin defects in various areas with little donor-site morbidity.