Psychosexual conflicts, personality factors, and cultural beliefs are considered as being of etiological

significance to koro. Sexual adjustment histories of non-Chinese victims are often significant, such as premorbid sex inadequacy, sexual promiscuity, guilt over masturbation, and impotence.

Koro is a culture-specific syndrome delusional disorder in which an individual has an overpowering belief that one's genitalia are retracting and will disappear, despite the lack of any true longstanding changes to the genitals. Koro is also known as shrinking penis, and it is listed in the "Diagnostic and Statistical Manual of Mental Disorders". The syndrome occurs worldwide, and mass hysteria of genital-shrinkage anxiety has a history in Africa, Asia, and Europe. In the United States and Europe, the syndrome is commonly known as genital retraction syndrome. The condition can be diagnosed through psychological assessment along with physical examination to rule out genuine disorders of the genitalia that could be causing true retraction.

Priapus, a minor Greek god of fertility, is marked by his oversized, permanent erection, which gave rise to the medical term priapism. Some researchers believe the depiction of Priapus' penis referred to a penile disease, and that paintings of Priapus were used to ward off the disease.

Aposthia is a rare congenital condition in humans, in which the foreskin of the penis is missing.

Toward the end of the nineteenth century, E. S. Talbot claimed that aposthia among Jews was evidence for the now-discredited Lamarckian theory of evolution. In his work, ""The Variation of Animals and Plants under Domestication"", Charles Darwin also mentioned cases of "born circumcised" babies as "conclusive evidence" for the now-discredited blending inheritance.

It is likely that the cases he described were actually hypospadias, a condition in which the urinary meatus is on the underside of the penis. Neither condition has been shown to have a higher frequency in Jews or Muslims.

Penetrating and blunt traumas combined make up approximately 90% of all civilian penile injuries (45% each), with burns and other accidents making up the remaining 10%.

Formicophilia, a form of zoophilia, is the sexual interest in being crawled upon or nibbled by insects, such as ants, or other small creatures. This paraphilia often involves the application of insects to the genitals, but other areas of the body may also be the focus. The desired effect may be a tickling, stinging or in the case of slugs, slimy sensation, or the infliction of psychological distress on another person. The term was coined by Ratnin Dewaraja and John Money in 1986 from the Latin "formica" (ant) + the Greek "philia" (love).

The causes of penile injury are mostly the same as other causes of trauma; however, penile injury is more likely to occur during sexual intercourse and masturbation than other traumas. Nocturnal erections and sleeping positions can be another cause of penile injury. Industrial and automobile accidents can also cause penile injury. Self-injury may also affect the penis.

Penile fracture is a relatively uncommon clinical condition. Vaginal intercourse and aggressive masturbation are the most common causes. A 2014 study of accident and emergency records at three hospitals in Campinas, Brazil, showed that woman on top positions caused the greatest risk with the missionary position being the safest. The research conjectured that when a woman is on top, she usually controls the movement and her entire body weight lands on the erect penis. She is not able to interrupt movement when the penis suffers a misaligned penetration. Conversely, when the man is controlling the movement, he has better chances of stopping the penetration thrusts in response to pain, minimizing harm to himself.

The practice of "taqaandan" (also "taghaandan") also puts men at risk of penile fracture. Taqaandan, which comes from a Kurdish word meaning "to click", involves bending the top part of the erect penis while holding the lower part of the shaft in place, until a click is heard and felt. Taqaandan is said to be painless and has been compared to cracking one's knuckles, but the practice of taqaandan has led to an increase in the prevalence of penile fractures in western Iran. Taqaandan may be performed to achieve detumescence.

Penile Artery Shunt Syndrome (PASS) is an iatrogenic clinical phenomenon first described by Tariq Hakky, Christopher Yang, Jonathan Pavlinec, Kamal Massis, and Rafael Carrion within the Sexual Medicine Program in the Department of Urology, at the University of South Florida, and Ricardo Munarriz, of Boston University School of Medicine Department of Urology in 2013. It may be a cause of refractory Erectile Dysfunction in patients who have undergone Penile Revascularization Surgery.

Diphallia, penile duplication (PD), diphallic terata, or diphallasparatus, is a rare developmental abnormality in which a male is born with two penises. The first reported case was by Johannes Jacob Wecker in 1609. Its occurrence is 1 in 5.5 million boys in the United States.

When diphallia is present, it is usually accompanied by renal, vertebral, hindgut, anorectal or other congenital anomalies. There is also a higher risk of spina bifida. Infants born with PD and its related conditions have a higher death rate from various infections associated with their more complex renal or colorectal systems.

It is thought diphallia occurs in the fetus between the 23rd and 25th days of gestation when an injury, chemical stress, or malfunctioning homeobox genes hamper proper function of the caudal cell mass of the fetal mesoderm as the urogenital sinus separates from the genital tubercle and rectum to form the penis.

Penile fracture is a medical emergency, and emergency surgical repair is the usual treatment. Delay in seeking treatment increases the complication rate. Non-surgical approaches result in 10–50% complication rates including erectile dysfunction, permanent penile curvature, damage to the urethra and pain during sexual intercourse, while operatively treated patients experience an 11% complication rate.

In some cases, retrograde urethrogram may be performed to rule out concurrent urethral injury.

Penile Revascularization is a specialized vascular-surgical treatment option for Erectile Dysfunction. The 2009 International Consultation on Sexual Dysfunctions recommended that revascularization be limited to nonsmoker, nondiabetic men younger than 55 years of age with isolated stenosis of the internal pudendal artery with absence of venous leak.

Patients with persistent erectile dysfunction after revascularization may benefit from repeat penile duplex ultrasound and pelvic angiography to evalauate the status of the bypass graft and to exclude the presence of a PASS as the cause. The prevalence of an aberrant obturator artery arising from the inferior epigastric artery is approximately 10.5%. If an aberrant obturator artery is visualized arising from the inferior epigastric artery prior to surgical penile revascularization, consideration should be given toward using an alternative source artery or to embolization to avoid the creation of a Penile Artery Shunt Syndrome encountered in this described case.

A ectopic testis is a testicle that, although not an undescended testicle, has taken a non-standard path through the body and ended up in an unusual location.

The positions of the ectopic testis may be: in the lower part of the abdomen, front of thigh, femoral canal, skin of penis or behind the scrotum. The testis is usually developed, and accompanied by an indirect inguinal hernia. It may be divorced from the epididymis which may lie in the scrotum.

A number of medical reports of phimosis incidence have been published over the years. They vary widely because of the difficulties of distinguishing physiological phimosis (developmental nonretractility) from pathological phimosis, definitional differences, ascertainment problems, and the multiple additional influences on post-neonatal circumcision rates in cultures where most newborn males are circumcised. A commonly cited incidence statistic for pathological phimosis is 1% of uncircumcised males. When phimosis is simply equated with nonretractility of the foreskin after age 3 years, considerably higher incidence rates have been reported.

Others have described incidences in adolescents and adults as high as 50%, though it is likely that many cases of physiological phimosis or partial nonretractility were included.

Sigmund Freud has footnoted the possibility that this fear may be derived from a lack of ingenuity allowing one to ornamentally distance the copulatory organs from the excretory organs. Such a condition can affect both men and women. For others, symptoms include what characterizes a panic attack. It does not necessarily have to be induced by an uncovered penis, but may also result from seeing the manbulging outline or curvature of the penis, perhaps through clothes consisting of thin fabric. In more extreme cases it has been likened to the fight or flight response ingrained within the human body wherein an individual ceases to be intimate with their male partner and is unable to visit mixed gender establishments where people are likely to wear more revealing clothing, such as a gym, beach, cinema or livingrooms with a switched on monitor. The fear can recur through any of the senses including accidental touch, sight, hearing the word penis or thinking about an erection. The phobia may have developed from a condition such as dyspareunia, a trauma (usually sexual) that occurred during childhood, but can also have a fortuitous origin. In literature covering human sexuality, it is used as an adjective only to negatively allude to penetrative sex acts. Men who have the phobia may try to avoid wearing jeans and other light fabrics, especially in public. Some analysts have purported that the condition may be inherited or may be a combination of genetic inheritance and life experiences. For men with the condition, one of the byproducts is difficulty consummating with a partner due to a sense of vulnerability. This vulnerability may have developed during childhood because they grew up being told by their parents that sex and its physiological functions were evil, sinful and dirty, but were subsequently unable to detach such shameful feelings nor reverse it upon reaching adulthood, even when romantic initiatives were subsequently approved of or encouraged by their parents.

Summer penile syndrome (also known as 'Lions Mane Penis') is a seasonal pediatric medical condition characterized by redness, swelling (Edema), and itching (pruritus) of the penile skin.

In the first reported case study, the patient had started keeping ants in a cupboard of his room as a hobby when he was nine. At this age he enjoyed "the ticklish feeling" of the ants crawling on his legs and thighs. At age ten, he had a sexual relationship with another boy, and was beaten when his father discovered this. By the age of 13 or 14, he had added snails and cockroaches to his collection, and was becoming increasingly preoccupied with it. He had begun masturbating while the ants crawled on his legs. At age 28, he was masturbating several times a week while cockroaches crawled on his thighs and testicles, and snails crawled over his nipples and penis. Sometimes he would hold a frog against his penis and enjoy the vibrations as it tried to escape. The patient was disgusted by his habit, but derived no pleasure from normal sexual activities. John Money suggested that the paraphilia developed as an alternative outlet after his normal sexual expression became associated with the trauma of his father's punishment.

Another case was described in 2012. At the age of 14, the patient saw an ice-cream stick covered with ants, and wondered how it would feel if his penis was in place of the stick. He began letting ants crawl on his genitals, especially fire ants, a practice he found sexually exciting and that continued into adulthood. The patient was socially and intellectually competent. He was also attracted to dogs and goats.

The most acute complication is paraphimosis. In this condition, the glans is swollen and painful, and the foreskin is immobilized by the swelling in a partially retracted position. The proximal penis is flaccid. Some studies found phimosis to be a risk factor for urinary retention and carcinoma of the penis.

Occurring at a rate between 1 in 10,000 to 1 in 50,000 with a male-to-female ratio of 2.3-6:1, bladder exstrophy is relatively rare. For those individuals with bladder exstrophy who maintain their ability to reproduce, the risk of bladder exstrophy in their children is approximately 500-fold greater than the general population.

Sclerosing lymphangitis is a skin condition characterized by a cordlike structure encircling the coronal sulcus of the penis, or running the length of the shaft, that has been attributed to trauma during vigorous sexual play.

Nonvenereal sclerosing lymphangitis is a rare penile lesion consisting of a minimally tender, indurated cord involving the coronal sulcus and occasionally adjacent distal penile skin. This disorder most often occurs after vigorous sexual activity and resolves spontaneously.

Etiology of Sclerosing lymphangitis is unknown but has been postulated to be secondary to thrombosis of lymphatic vessels. Spontaneous recovery can occur anywhere within a couple weeks to several months.

Although it is commonly recommended the patient abstain from any sexual activitiy during the recovery, there is no evidence that this expedites recovery nor that not abstaining worsens the condition.

Mondor's disease (also known as "Mondor's syndrome of superficial thrombophlebitis") is a rare condition which involves thrombophlebitis of the superficial veins of the breast and anterior chest wall. It sometimes occurs in the arm or penis. In axilla, this condition is known as axillary web syndrome.

Patients with this disease often have abrupt onset of superficial pain, with possible swelling and redness of a limited area of their anterior chest wall or breast. There is usually a lump present, which may be somewhat linear and tender. Because of the possibility of the lump being from another cause, patients are often referred for mammogram and/or breast ultrasound.

Mondor's disease is self-limiting and generally benign. A cause is often not identified, but when found includes trauma, surgery, or inflammation such as infection. There have been occasional cases of associated cancer. Management is with warm compresses and pain relievers, most commonly NSAIDS such as ibuprofen. When thrombophlebitis affects the greater veins, it can progress into the deep venous system, and may lead to pulmonary embolism.

It is named after Henri Mondor (1885-1962), a surgeon in Paris, France who first described the disease in 1939.

Peyronie's disease can be a physically and psychologically devastating disease. While most men will continue to be able to have sexual relations, they are likely to experience some degree of deformity and erectile dysfunction in the wake of the disease process. It is not uncommon for men afflicted with Peyronie's disease to exhibit depression or withdrawal from their sexual partners.

Summer penile syndrome is usually caused by chigger bites on the penis. Majority of cases occur in the summer months, with the clothing associated with warmer weather making penis-insect contact more likely.

Frenulum breve may be complicated by tearing of the frenulum during sexual or other activity and is a cause of dyspareunia. It may lead to erroneous labelling of the sufferer as having psychosexual problems. The torn frenulum may result in healing with scar tissue that is less flexible after the incident causing further difficulties. However, this tearing can also solve the problem, healing such that the frenulum is longer and therefore no longer problematic. The diagnosis of frenulum breve is almost always confused with that of phimosis and a generally tight foreskin, since the symptom is difficulty retracting the foreskin. Most men with phimosis also have frenulum breve to a certain extent.

Inflammation has many possible causes, including irritation by environmental substances, physical trauma, and infection such as bacterial, viral, or fungal. Some of these infections are sexually transmitted diseases.

It is less common among people who are circumcised as in many cases the foreskin contributes to the disease. Both not enough cleaning and too much cleaning can cause problems. Diabetes can make balanitis more likely, especially if the blood sugar is poorly controlled.

It is important to exclude other causes of similar symptoms such as penile cancer.