Combined Pedicled Trapezius Flap With Negative Pressure Wound Therapy for Treating a Traumatic Chest Wall Defect With Intrathoracic Infection

Traumatic chest wall defect normally involves severe tissue damage.¹ Most patients die before rescue because the progress of the disease is dramatically rapid. Those patients who manage to arrive to the emergency department still face a high mortality due to difficulties in treating the disease and its complications.² Therefore, few cases of reconstruction of traumatic chest wall defect have been reported. Both soft tissues and bony structures may need to be reconstructed for a chest wall defect³. However, whether or not to restore the skeletal stability of the chest wall is still being debated.³ When the size of the soft tissue defect is larger than 5 cm, locoregional muscle flaps are commonly needed to cover the defect. The most frequently used muscle flaps are pectoralis major, latissimus dorsi, serratus anterior, and rectus abdominis.⁴ However, if these muscles cannot be used in patients with a massive chest wall defect, no consensus has been reached on which flap to use as an alternative. Free flap is one of the options.⁴ The advantages of free flaps are the relatively controllable size of the donor site and that they have no effect on respiratory function. However, it has a higher failure risk compared with the locoregional muscle flaps due to a high requirement for the condition of recipient vessels and soft tissues. Complete debridement and infection control are the basis for a successful reconstruction of the chest wall.⁵ Traditionally, intrathoracic infection is treated with closed thoracic drainage and antibiotics. As a new treatment method, negative pressure wound therapy has a remarkable effect on controlling infection and promoting would healing,^6,7 but only a few studies reported its application for intrathoracic infection.⁸ This report describes a case in which a massive traumatic chest wall defect with intrathoracic infection was successfully reconstructed by combining pedicled trapezius flap and negative pressure wound therapy.

A 46-year-old male patient sustained a traumatic amputation of his right upper extremity in a forklift accident. The scapula and clavicle were partially amputated, and the right lung was exposed to the outside. The patient was admitted to the local hospital and underwent an emergency surgery. The wound was debrided of all devitalized tissue and covered by the negative pressure wound therapy materials. The ribs were fixed by a claw. Meanwhile, the patient required mechanical ventilation and extensive blood transfusion to maintain the circulation system. The patient developed an extensive soft tissue necrosis 5 days later, and a second debridement was conducted. The mechanical ventilation was changed to tracheotomy ventilation. The patient developed a severe and uncontrollable intrathoracic infection 3 days later and transferred hospitals. 

At the time of presentation to the second hospital, the right pectoralis major, pectoralis minor, intercostal muscles, the majority of the latissimus dorsi, and ribs 1-5 of the patient were necrotic (Figure 1). The rib claw was loose. The lung was exposed to the outside and was covered by pus and necrotic tissues (Video 1). The intrathoracic cavity was full of pus as well. During the debridement, all of the necrotic tissue was resected and the negative pressure wound therapy materials filled into the intrathoracic space for an adequate drainage. The defect was covered by the negative pressure wound therapy materials. The infection was controlled following an additional 2 rounds of debridement. The chest wall was left with a massive defect that required reconstruction. 

The chest wall defect was too large for any single muscle flap to completely cover the defect. After a complete debridement, the right anterolateral thigh flap was selected to cover the lung and the defect as much as possible (Figure 2). The size of the anterolateral thigh flap was 37 x 18 cm. The lateral femoral circumflex artery was anastomosed with the right superior thyroid artery. The 2 accompanying veins were anastomosed with superior thyroid vein and internal jugular vein, respectively. Negative pressure wound therapy materials covered the rest of the defect. Unfortunately, the flap developed a vascular crisis 3 days later and ultimately devitalized because the anastomotic artery developed thrombus due to infection of the tracheotomy site. 

An additional 3 rounds of debridement combined with negative pressure wound therapy were needed to control the infection. During the last debridement, the trapezius flap was used to cover the lung, with the intercostal artery perforator flap and negative pressure wound therapy materials covering the rest of the defect (Figures 3 and 4). The size of the trapezius flap was 35 x 12 cm, and the size of the intercostal artery perforator flap was 20 x 10 cm. However, most of the intercostal artery perforator flap was necrotic 10 days later. Another debridement was conducted, and a thin scalp cutting from the patient’s head was cropped into small pieces and implanted to the wound. At this time point, all the surgeries were completed and the trapezius flap survived well. During the surgeries, use of prosthetic materials was attempted to reconstruct the rigid chest; however, the infection could not be controlled with use of the prosthetic materials. All prosthetic materials were eventually removed, and only muscle flaps were used to cover the defect. The patient resumed normal life after the surgery (Figure 5). At 2-year follow-up, respiratory function was barely affected but the trapezius flap moved when the patient breathed (Video 2).

In this case, the negative pressure wound therapy shows its advantages in controlling intrathoracic infection. This report describes placing negative pressure wound therapy materials into all the dead space in the chest, which ensure an adequate drainage of the pus and the necrotic tissues. Meanwhile, the negative pressure dressing can simulate the natural negative pressure in the chest, promoting lung recruitment and minimizing the effect of the infection on respiratory function.  The negative pressure wound therapy materials can also improve the quality of the local granulation tissue by increasing blood flow and local oxygen supply and decreasing the tissue edema, which provides a bed for subsequent reconstruction with muscle flaps. The application of negative pressure wound therapy to intrathoracic infection has been proven effective.⁸ Previous studies have shown that the application of negative pressure wound therapy can improve the success rate of implanted muscle flaps.⁷ 

The most commonly used pedicled muscle flaps for chest reconstruction are the pectoralis major and the latissimus dorsi.⁴ In this case, the pectoralis major, the latissimus dorsi, and most parts of the right chest wall were damaged. The right anterolateral thigh flap was initially chosen to cover the chest wall defect as much as possible. However, the flap ultimately devitalized due to infection. The free muscle flaps use a special microsurgical vascular anastomosis technique and require high-quality granulation tissue, which increases the risk of failure. In this case, the infection of the wound and the intrathoracic space were controlled. Nevertheless, the infection from the site of tracheotomy ventilation spread to the free muscle flap, which finally caused a thrombus in the anastomotic artery. This case suggests that, if the free muscle flap is to be transplanted, the infection of the wound and all potential infections near the wound need to be completely controlled. Additionally, the trapezius flap was previously shown to be a robust and simple option in reconstruction of other body defects.^9-11

Normally, reconstruction of the chest wall defect also includes the reconstruction of the rigid structures. In this case, the patient also had a defect of ribs 1-5. Prosthetic materials were used to maintain the rigid part of the chest in the initial stage; however, the infection could not be controlled with the prosthetic materials in the wound. Eventually the prosthetic material was abandoned and only the trapezius muscle flap was used to cover the chest wall defect. Though the muscle flap moved with breathing, it did not affect respiratory function of the patient. 

Patients with a massive traumatic chest wall defect have a high rate of mortality. The survival depends on timely rescue and multidisciplinary cooperation in treatments. This case report describes the reconstruction of a massive traumatic chest wall defect with intrathoracic infection by combining pedicled trapezius flap with negative pressure wound therapy. Negative pressure wound therapy techniques show advantages in controlling intrathoracic infection for continuous drainage and isolation from outside. The negative pressure wound therapy also promotes the growth of the granulation tissue, which provide the reconstruction bed for the muscle flaps. Effective debridement and complete infection control ensure success of the muscle flap transplantation. The trapezius muscle flap can successfully reconstruct the chest wall defect when the commonly used muscle flaps—such as pectoralis major, latissimus dorsi, serratus anterior, and rectus abdominis—are damaged during the trauma. 

Affiliations: Department of Orthopedic Surgery, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China

Corresponding author: Ning Qu; quningsmile@yahoo.com

Ethics: This study conforms to the Declaration of Helsinki ethical principles for medical research. 

This study was approved by IRB, and informed consent was obtained from the patient.

Disclosures: The authors have no relevant financial or nonfinancial interests to disclose.