Various defects may occur following radical resection of head and neck tumours, and a considerable portion of these defects requires free flap repair 7-9. The quality of repair directly affects patients' postoperative recovery and quality of life. There are two key factors that affect the quality of repair, namely, the surgical skill and clinical experience of the surgeon and the correct flap selection 5, 10-12. Oral and oropharyngeal mucosa is soft, and the function of the relevant organ is very complex and sophisticated. Therefore, when repairing oral or pharyngeal defects, a ductile skin flap should be used whenever possible. Only in this way can a patient's oral oropharyngeal morphology and function be restored. This TDAPs can well meet the demand of softness for head and neck defect repair. Our study is the largest application of TDAPs to repair head and neck defects in mainland China at present. Meanwhile, we also reported a pedicle double island TDAP for the first time.
Stable, quantitative measurements of skin hardness and elasticity have long been lacking 13, 14. In this study, we used the ElastiMeter and SkinFibroMeter in a novel way to measure the elasticity and hardness of the skin flap, demonstrating that these tools can quantitatively evaluate skin elasticity and stiffness. The ElastiMeter and SkinFibroMeter also have the advantages of being highly sensitive, portable and accurate. Unlike diagnostic methods based on skin biopsy and puncture, ElastiMeter and SkinFibroMeter measurements are non-invasive and do not damage skin structures, thereby reducing patient anxiety. In addition, the wireless data collection system uses DMC software, enabling real-time data acquisition and storage. The measurement process is simple, requiring only depression of the operation button and adjustment of the power and velocity of the probe. The site of measurement was the donor site of the flap, not the flap.This can avoid measurement errors between different patiens. In this study, the use of these measurements revealed that TDAP donor skin is the most ductile of all commonly used skin flaps—even softer than the forearm, which is considered to be the softest flap. The use of TDAP for repair of oral or pharyngeal defects also led to full recovery of swallowing, speaking and other functions, as confirmed by patient follow-up.
When choosing a flap, scarring and other complications at the donor site are other important considerations. The surgical incision at the donor site of TDAP is concealed under the armpit, and the average surgical scar is only 14.5 cm. In addition, because the flap was prepared with retention of the important nerves, there was almost no damage to the adjacent muscles. As a result, there was no serious dysfunction in the postoperative donor site. In this study, the most common donor site complications included localised paraesthesia, muscle weakness and poor wound healing. The main causes of the above complications are intraoperative injury of the latissimus dorsi muscle motor nerve and cutaneous nerve 15, 16. Therefore, during flap preparation, the latissimus dorsi muscle motor nerve and cutaneous nerve should be protected as much as possible with avoidance of large suture tension to minimise donor site complications.
In the current study, all of the transplanted flaps survived. Factors known to influence the success rate of skin flap transplantation 17 include the surgeon's clinical experience and a good match between the vascular diameter of the skin flap and the neck. The diameter of the arteries and veins of the TDAPs was about 2 mm, which is suitable for anastomosis with the head and neck vessels. From this point of view, TDAPs are very suitable for reconstruction and repair of head and neck defects.
Although TDAPs offer many advantages for repair and reconstruction of head and neck defects, there are two notable disadvantages. First, there may be some interference with head and neck surgery when preparing the flap. Both groups could be performed simultaneously if necessary. Second, the thickness of TDAPs is too great in some patients, and a thinning treatment may be required.