Scarring, like many other diseases, is all about prevention. Once a scar is formed, it can be very tricky to treat. Surgical treatment is the most direct and effective way, but the surgical incision itself is a new trauma that will produce surgical incision scarring. Even with the most delicate surgical methods, the scar can only be improved, but not completely eradicated. Therefore, taking various measures to maximize the prevention of scar proliferation has the same significance as the treatment of scar. I. Early post-injury prevention Patients after burns, trauma and other traumas should seek medical attention as early as possible, treat the trauma properly and prevent or effectively control infection in a timely manner. Patients with burns should have their wounds closed by cutting, chipping or scabbing as soon as the systemic condition permits, such as performing skin grafting. After the trauma is healed, elastic bandage or elastic sleeve should be used for pressure in time to reduce scar growth, and external fixation should be applied in time to keep the joint in a functional position to minimize the deformity caused by scar contracture. The common sequelae of post-traumatic scarring include pruritus, burning pain, recurrent ulcers, scar hyperplasia or contracture deformity. Patients with severe scarring can often have a combination of these symptoms and require surgical treatment. Our center has summarized a set of principles to prevent and treat scarring in our long-term clinical frontline work to minimize scar proliferation and reduce patient pain. This includes reasonable selection of surgical patients, treatment of trauma, fine surgical operation techniques and proper postoperative care. 1. Patient selection Patient selection, i.e., accurate grasp of surgical indications. For scar patients with existing malignant disease or malignant tendency, or scar patients with severe dysfunction or ulcer, there is no choice but to operate. However, for patients with common scars, especially those who require cosmetic and cosmetic improvement, plastic surgeons should carefully grasp the indications for surgery and evaluate whether surgical treatment can improve the original scar to a greater extent before surgery, weighing the advantages and disadvantages of surgical treatment, especially when the scar is not obvious or located in a concealed area or without functional impairment. This is because if the surgical treatment is not done properly, it may make the existing scar more pronounced. Extra caution should also be taken for the sites where keloid hyperplasia and keloids are prevalent, such as the chest and shoulders, the sites where tension and movement exist, such as the upper part of the chest, the scapula, and the flexed side of the limbs, and the sites where breast gravity and chest breathing movement exist, such as the sternum, where the postoperative scar is prone to hyperplasia. 2.Wound treatment Some patients who come to the clinic still have unhealed wounds. For early fresh wounds, blood clots, foreign bodies and debris should be thoroughly removed, as well as tissues that are determined to have lost vitality. Close the trauma as early as possible; if the trauma is left to heal on its own, scar hyperplasia, scar contracture, and adhesions to deeper tissues often form. For late contaminated wounds, if the possibility of infection exists, the wound should be thoroughly debrided and drainage placed when the wound is closed. If infection has been determined to exist, antibiotics should be applied locally or systemically and the trauma should be closed in phase II after the infection has been controlled. For wounds with large tissue defects, tissue mobilization should be taken as early as possible to cover the wound to reduce granulation tissue and scar tissue formation. Advancing flaps, rotating flaps, distal flaps, or free skin grafts may be used. Sometimes, the simplest surgical approach is often the wisest. Unnecessary additional incisions should be avoided whenever possible, especially in patients with a tendency to keloid scarring. There are many surgical procedures, including direct excision and suturing, local reshaping, skin expansion, flap transfer or free grafting, depending on the patient’s condition. Although the surgical modalities are different, the following principles should be followed: Principles of surgical incision design (1) Choose the hidden area, such as under the breast, hair area, etc. Temporal or lateral neck surgery can be chosen in the hairline area. Choose incisions along the contour line, such as nasolabial folds, anterior axillary line, etc.; incisions along the skin line, such as in the forehead, eyelids, etc.; in the natural union, such as the ear-neck union, etc. The scar formation is less obvious or more concealed in these parts of the incision or trauma, which is more in line with the aesthetic features. (2) The incision at the extremities and joints is chosen at the flexion crease line or parallel to the skin tension line, avoiding making circular circular incisions or straight incisions across the joint surface. The purpose is to reduce the restriction of joint movement caused by scar contracture, and even joint deformity. (3) When the external body cavity must cross the contour line and skin line, a “Z” reshaped incision should be designed to facilitate the recovery of function after surgery. Intraoperative operation Plastic surgery must be operated in strict accordance with the principles of aseptic and non-invasive techniques to strive for one-stage healing of the incision. The operation should be performed gently and the instruments should be sharp to avoid unnecessary injuries. Hemostasis should be adequate and precise to reduce the possibility of postoperative hematoma complications. Wound closure should be accurate and without dead space formation. Suturing Tension-free suturing is the key. Tension-free suturing of the incision will inevitably result in significant scarring, regardless of the suturing method used. Each layer of tissue should be precisely aligned to fully reduce tension, and the skin should be sutured with the wound edges aligned, not too tight, to avoid necrosis of the tissue around the sutures. While satisfying the surgical effect, try to achieve small stitches and fine lines. Postoperative treatment (1) Wound dressing and dressing change Wound dressing and dressing change after plastic surgery is not only to protect the wound from infection, but also to achieve various purposes such as auxiliary fixation, elimination of latent cavity, prevention of secondary bleeding to form hematoma or venous stasis, and reduction of edema. The dressing at the end of the operation, the determination of the time for the first dressing change and the removal of stitches should be operated and mastered by the operator or the personnel who are familiar with the surgical procedure. (2) Symptomatic management of surgical incision scar As mentioned above, the surgical incision itself is a new trauma and will produce an incision scar. The surgical incision scar is far different from the scar with obvious hyperplasia and even contracture deformity. Depending on the patient’s physique, if no obvious hyperplasia occurs, it is usually a linear, low flat, light-colored scar that gradually fades over time. After the incision heals well, topical medication and timely compression with an elastic bandage or elastic sleeve are often used for the purpose of inhibiting scar proliferation. (3) Functional exercise Long-term dysfunctional limb deformity, mostly accompanied by joint stiffness and muscle atrophy, cannot be completely restored by surgery alone. Surgical treatment creates conditions for limb function improvement, and postoperative functional exercises, such as physical therapy, physiotherapy, occupational therapy, and auxiliary measures such as elastic traction and braces, are required to achieve maximum functional recovery. For the prevention and treatment of refractory scar (keloid), in addition to following all the above principles and enforcing them more strictly, a comprehensive treatment including drug injection, radiotherapy, physiotherapy and other treatments should be carried out after surgery to minimize postoperative recurrence.