2.1.1 Surgical Technique
A Siemens 64-slice dual-source CT and colour Doppler ultrasound diagnostic apparatus (Siemens Acuson Sequoia 512, Germany) was used to scan and locate the perforators of the thoracodorsal arteries in the donor areas of the patients. Major and long perforators were selected, and their courses, the locations of the exit points, the approximate diameters of the perforators, and adjacent structures were marked.
The procedure was performed under general anaesthesia. Briefly, the patient was placed in the lateral decubitus position with abduction of the shoulder on the donor area side. The operative field was disinfected.
The anterior edge of the latissimus dorsi muscle and the scapula were marked. The connecting line between the posterior axillary wall and the posterior superior iliac spine was used as a reference axis to design the flap. According to the sizes and shapes of the hand wound defects, we designed the flap along the major thoracodorsal artery perforators. The area size of flap was appropriately enlarged according to the thickness of the fat at the donor site.
According to the design line of the flap, an incision was made at the medial edge of the flap. Separation was performed medially from the subcutaneous tissue layer towards the lateral side until the marked points of the major perforators were reached. Then an incision was made along the design line to incise the lateral edge of the flap. While vascular pedicles of adequate length were completely developed, the flap was divided to polyfoliate flaps with the pedicle intact. Thus, each flap had an independent perforator. The wound at the donor site was directly closed with sutures.
Then, the patient was placed in the supine position. The vessels of the flap were perfused using diluted heparin and lidocaine to identify open branches from the pedicle. Any open branches of each perforator were ligated. Then, the flap was moved to the recipient area and secured with intermittent sutures. The artery of the pedicle was anastomosed to an artery in the recipient area. An accompanying vein of the pedicle was anastomosed to an accompanying vein of the artery in the recipient area, and the other accompanying vein was anastomosed to the superficial vein. End-to-end anastomosis was used in this procedure unless a large diameter difference between the two vessels was evident; if a large difference was evident, end-to-side anastomosis was used.
After surgery, the patient was admitted to the flap transplantation intensive care unit where he or she was treated with anti-inflammatory, antispasmodic, and anticoagulant agents. The patient was cared for in a quiet room with a temperature of 25–28°C and maintained complete bed rest for one week. Assigned staff observed the blood supply of the flaps every hour.
2.1.2 Surgical subjects
Patients with hand skin and soft tissue defects who were admitted to Ningbo No. 6 Hospital (Ningbo, China) from January 2015 to February 2018 and met the inclusion criteria were included in the study. The inclusion criteria were multiple skin and soft tissue defects in the hand, exposed deep tissues, and the lack of availability of a single flap to repair all the wounds. The exclusion criteria were age > 60 years, severe arteriosclerosis in the blood vessel of the recipient area, wound infection, and restrictions to free flap use due to damaged blood vessels in the recipient area. After being informed of the details of the surgery, the patients chose the surgical plan and signed the informed consent form for surgery and for participation in this study.
Fifteen patients were enrolled in the study, including 12 men and three women, with an average age of 37.7 years (range: 19 to 48 years). The causes of injury included crush injury (11 patients), thermal pressure injury (three patients), and car accident injury (one patient). The injury sites included the fingers (six patients), the dorsum of hand (six patients), and the dorsum of hand combined with the fingers (three patients). All patients presented with bone or extensor tendon exposure, and three patients had extensor tendon defects. The skin defect area (cm2) was 25.2 (range: 15 to 43 ). Wound debridement was performed in all 15 patients during emergency surgery, and the wounds were covered with flaps approximately one week later once the wounds were free of infection.
Free thoracodorsal artery polyfoliate perforator flaps for the repair of skin defects on the dorsum of the right hand and the dorsal side of the thumb.
A 40-year-old man presented with a crush injury of the right hand and skin defects on the dorsal side of the hand and thumb. CTA and colour Doppler ultrasound were performed to locate the perforators, and then free thoracodorsal artery polyfoliate perforator flaps were used to repair the defects. The artery and veins of the pedicle were anastomosed (end-to-end) to the radial artery, the radial vein, and the cephalic vein, respectively. The flap survived with a good blood supply. The wound at the donor site was closed directly. (Fig. 1)
Free thoracodorsal artery polyfoliate perforator flaps for the repair of skin defects on the right index and middle fingers.
A 23-year-old man was admitted to the hospital due to a wound defect in the right middle finger caused by a car accident. After initial debridement, free thoracodorsal artery polyfoliate perforator flaps were used to repair the wound. The artery and veins of the flap were anastomosed (end-to-end) to the radial artery, radial vein, and the cephalic vein, respectively. The flap survived. The wound at the donor site was directly closed with sutures and was relatively invisible. (Fig. 2)