The principle of penile lengthening surgery is the main procedure to treat penile dysplasia, small penile deformities and traumatic partial penile defects. Many patients have a strong sense of inferiority due to short penis, and some patients with short penis have difficulty in making the female partner reach orgasm during sex, so they all hope to solve these problems through safe penis lengthening surgery. The length of normal adult penis in China is about 4.5~11.0cm in normal condition, with an average length of 7.1±1.5cm and a circumference of about 5.5~11.0cm, with an average circumference of 7.8±0.7cm; when erect, the length is about 10.7~16.5cm, with an average of 13.0±1.3cm and a circumference of about 8.5~13.5cm, with an average of 12.2±1.2cm. If the length of the penis is less than 10 cm when erect and the sexual life is not harmonious, penile lengthening is feasible according to the patient’s request. Principle of penile lengthening In the past, some scholars believed that the sex-sensitive zone of women existed only in the clitoris, labia and 2/3 area from the inner vaginal opening, so the length of the penis did not affect the quality of sexual life, but according to recent studies, the sex-sensitive zone also exists in the distal 1/3 of the vagina of women, and women tend to get strong sexual pleasure by repeatedly sliding the penis from the cervix to the fornix, which provides a theoretical basis for penile lengthening provides a theoretical basis for penile lengthening. The penis consists of two penile corpus cavernosum and one urethral corpus cavernosum, the root of which is fixed to the pubic arch by two penile corpus cavernosum feet, and the body of the penis is fixed to the lower part of the pubic symphysis and the abdominal white line by means of the penile suspensory ligament. The penile suspensory ligament is divided into the superficial penile suspensory ligament and the deep penile suspensory ligament. According to the anatomical study, the thickness of the superficial suspensory ligament of the penis is about 0.6-2.0cm; the thickness of the deep suspensory ligament of the penis is about 2.2-2.8cm. the length from the anterior edge of the superficial suspensory ligament of the penis to the posterior edge of the deep suspensory ligament of the penis is about 4.0-6.8cm, with an average of 5.5cm. when the superficial and deep suspensory ligaments of the penis are completely cut and separated to the pubic arch, the original fixed in the pubic symphysis and below the pubic bone branch When the superficial and deep suspensory ligaments of the penis were completely severed and separated to the pubic arch, the penis, which had been fixed under the pubic symphysis and the pubic symphysis, was fully free, thus increasing the length of the penile body. Because the penile corpus cavernosum foot is attached to the pubic arch and both sides of the sciatic branch, and covered by the sciatic corpus cavernosum muscle and tendon membrane, so that when the penis is erect, it can still maintain the erectile strength and stability of the penis, through a large number of cadaveric anatomy and clinical practice found that by cutting the penis shallow and deep suspensory ligament can make the penis extended 4 ~ 6cm. Indications for penile lengthening surgery 1, penile dysplasia: adult men who have penis If the length of the penis is less than 10cm in the erect state and the sexual life is not harmonious, penile lengthening is feasible according to the patient’s request. 2, partial penile defect: the development of the penile corpus cavernosum of such patients is basically normal. Penile lengthening can be performed first by cutting off all the superficial and deep suspensory ligaments of the penis, or even separating to the foot of the penile corpus cavernosum, so that the penile corpus cavernosum buried in front of the pubic symphysis can be freed, and the abdominal flap, inguinal flap or scrotal flap can be used to wrap around the exposed penile corpus cavernosum wound. With this method instead of penile reconstruction, not only can the length of the penis be effectively extended, but also make the penis have normal sensation and erectile function after surgery. 3, small penile deformity: after endocrine treatment in early childhood and adolescence, the length and circumference of the penis are still much lower than normal, and penile lengthening and thickening surgery is feasible to improve penile morphology. 4.Cryptogenic penis or cryptogenic transposition of penis: while performing the correction of cryptogenic penis or cryptogenic transposition of penis, the superficial and deep suspensory ligaments of penis can be cut off, which can fully extend the penis and make the form of penis more satisfactory after surgery. However, at the same time, attention should be paid to the presence of urethral defects or opening abnormalities. 5, penile venous erectile dysfunction: performing penile lengthening at the same time as ligation of superficial and deep veins of the dorsal penis can achieve better results. Penis lengthening surgery methods and steps 1, preoperative preparation: preoperative perineal skin preparation, measurement of the length and circumference of the penis in normal and erect state, preoperative conversation to inform patients and their families that the root of the penis may be slightly shifted downward after surgery, and the root of the penis may appear depressed in the short term. 2.Anesthesia: The anesthesia method is chosen according to the patient’s age, and epidural or general anesthesia is usually used. 3.Position: supine position. 4.Surgery：Surgical methods and steps Anterior pubic arch cavernous extension method (Long’s penile lengthening) This procedure was pioneered by Professor Long Daochou in 1984. This procedure avoids the dorsal penile artery and the dorsal penile nerve, and sexual function is not affected after the operation. At the same time, part of the superficial dorsal penile vein is ligated during the operation, so that the erectile function of some patients with penile venous erectile dysfunction is improved. The entire skin is incised according to the designed incision, and the superficial penile suspensory ligament is exposed by separating downward layer by layer. The head of the penis is pulled so that the penile suspensory ligament is under tension, and the superficial fascia and loose connective tissue on both sides of the suspensory ligament are separated. After cutting the superficial suspensory ligament of the penis, the deep suspensory ligament of the penis can be seen beneath it. Cut the deep suspensory ligament and separate the penile corpus cavernosum to the pubic arch, or if necessary, separate part and continue to separate part of the corpus cavernosum foot, so that the penile corpus cavernosum originally fixed to the subpubic branch can be fully separated to make the penis more extended. The wound is thoroughly hemostatic, and the deep dorsal penile vein can be sutured if necessary. The adipose tissue and connective tissue on both sides of the pubic arch are freed to form two tissue flaps, which are filled in the space in front of the pubic arch after the superficial and deep suspensory ligaments of the penis are severed and sutured to the periosteum of the pubic symphysis, thus eliminating the dead space and preventing re-adhesion of the ligaments. The incision margins were sutured in layers according to the incision design. Postoperative treatment of penile lengthening surgery 1. The penis is fixed upward after surgery so that there is no tension in the flap at the root of the penis; 2. After surgery, pay attention to the oozing and edema of the incision at the root of the penis and observe the blood flow of the flap at the root of the penis; 3. To inhibit penile erection, you can start taking hexestrol 4mg orally or intramuscularly two days before surgery, 1 time/day, or chlorpromazine 12.5mg, 1 time/day, and isopromazine 25mg, 1 time/day; 4. 4. Remove the catheter about 3 to 4 days after the operation; 5. 5 days after the operation, start to pull the head of the penis forward and down, start to pull lightly. 7 days later, gradually increase the weight to avoid adhesions between the two severed ends of the superficial suspensory ligament; 6. 2 weeks after the operation, remove the stitches; 7. 7. After the operation, you should lie down as much as possible, and use an elastic bandage with appropriate pressure to wrap the penis to promote the edema to subside; 8. 6 weeks after the operation, prohibit sexual intercourse. Penis lengthening surgery complications and treatment 1, post-operative penile foreskin edema: post-operative penile foreskin edema is the most common complication after penile lengthening surgery, generally appearing 3-5 days after surgery, lasting 5 to 10 days. It is manifested as penile foreskin swelling, foreskin surface skin shiny, common penile distal foreskin edema is heavier, especially the ventral tether edema is most obvious. As part of the superficial dorsal penile vein and part of the lymphatic vessels are cut off during surgery, and some even cut off the deep dorsal vein, resulting in partial lymphatic and venous return obstruction, penile foreskin edema often occurs. In addition, abnormal erection of the penis after surgery can also aggravate the obstruction of penile reflux, and excessive activity of the patient out of bed early can also cause edema due to gravity. Preventive and curative measures: ① Ask the patient to lie down as much as possible after the operation; ② Apply blood-stasis-activating drugs for swelling treatment; ③ Use elastic bandage compression method for physical therapy in severe cases. 2, flap tip necrosis: flap tip necrosis is manifested as the penile root flap in the postoperative 48-72 hours, the flap tip whitening, dark red phenomenon. Then gradually become black and necrotic. Preventive measures: ① postoperative routine external fixation of the penis in neutral position to reduce the strain on the flap by penile draping to make the flap tension too high; ② postoperative suppression of penile erection; ③ application of insulation, microwave therapy, drugs and other methods to promote the blood circulation of the flap. Once this complication occurs, it should be actively dealt with. First of all, active drug exchange treatment should be taken, while removing the unfavorable factors affecting blood supply, and supplemented with drugs to improve microcirculation. The blood crust of the incision should be removed with hydrogen peroxide solution and antibiotic saline before the drug exchange. If it still cannot be improved, surgical debridement should be taken to remove the necrotic tissue and re-suture it. Auxiliary flap repair can be designed if the tension is high. 3, hematoma: The occurrence of hematoma is usually caused by incomplete intraoperative hemostasis or poor postoperative drainage. Because of the relative difficulty in exposing the surgical field of penile lengthening, it is difficult to stop bleeding; in addition, the blood supply of the perineum is relatively rich, and there is more blood leakage from the trauma, and poor postoperative drainage can also cause the occurrence of hematoma. Preventive measures: ① Strict and thorough intraoperative hemostasis, which is the most critical point; ② Place drainage tablets or drainage tubes in the surgical area for drainage, and observe the drainage every day; ③ Routine application of hemostatic drugs after surgery. The treatment of complications should be based on the above treatment using methods such as local pressure bandaging. If active bleeding is found by puncture, surgical incision should be actively performed to completely stop bleeding and remove the hematoma. 4, delayed wound healing: wound healing time is generally 12 to 16 days, so the removal time should be strictly limited to 2 weeks after, too early removal is not conducive to wound healing. If the wound still cannot heal after 3 weeks, it is considered as delayed wound healing. It is generally considered to be related to the patient’s organism condition and nutrition level, and improper postoperative care is also one of the reasons. For patients who require penile lengthening, the indications for surgery should be strictly grasped, and some people with serious organic lesions should be considered as contraindicated for surgery. Therefore, in addition to conventional treatment for this type of patients, systemic supportive treatment is also very important. In addition, the poor nutrition of some patients after surgery due to various reasons is also one of the reasons for delayed wound healing, and it is very important to strengthen the nutrition of patients comprehensively. 5.Infection: Infection occurs mostly due to the aseptic operation is not strict, postoperative drug change and improper care. As the postoperative patients often have relative difficulty in urination due to pain and foreskin edema, the situation of urine soaking the incision may also occur. Therefore, post-operative medication changes and care should be carried out in a timely and strict aseptic operation, and the incision should be closely observed. Because the surgical site of penile lengthening is special, postoperative antibiotics should be applied routinely to prevent infection. Once the infection occurs, the postoperative care and drug change treatment should be strengthened and sensitive antibiotics should be selected according to the drug sensitivity test. 6.Postoperative penile webbing deformity: strictly speaking, postoperative penile webbing deformity is not a real complication because this condition occurs because: ① the design and conduct of the surgical flap is mainly on the dorsal side of the penis; ② the skin on the ventral side of the penis is not supplemented accordingly after surgery, but is met by the elastic stretching of the skin; ③ when the length of penile lengthening exceeds the elastic limit of the ventral skin, the ventral side of the penis A web-like deformity is formed where the skin folds and the penile scrotum are connected. In order to ensure the viability of the flap, the surgeon retains too much of the flap and the penis becomes too bulky and webbed. For such patients, a second operation can be performed to correct the webbed penis, with a general interval of 3 to 6 months between phase I surgery and phase II shaping.