Although spinal cord injury (SCI) often causes sexual dysfunction, many people with SCI are able to have satisfying sex lives. Physical limitations acquired from SCI affect sexual function and sexuality in broader areas, which in turn has important effects on quality of life. Damage to the spinal cord impairs its ability to transmit messages between the brain and parts of the body below the level of the lesion. This results in lost or reduced sensation and muscle motion, and affects orgasm, erection, ejaculation, and vaginal lubrication. More indirect causes of sexual dysfunction include pain, weakness, and side effects of medications. Psycho-social causes include depression and altered self-image. Many people with SCI have satisfying sex lives, and many experience sexual arousal and orgasm. People with SCI may employ a variety of adaptations to help carry on their sex lives healthily, by focusing on different areas of the body and types of sexual acts. Neural plasticity may account for increases in sensitivity in parts of the body that have not lost sensation, so people often find newly sensitive erotic areas of the skin in erogenous zones or near borders between areas of preserved and lost sensation.
Drugs, devices, surgery, and other interventions exist to help men achieve erection and ejaculation. Although male fertility is reduced, many men with SCI can still father children, particularly with medical interventions. Women's fertility is not usually affected, although precautions must be taken for safe pregnancy and delivery. People with SCI need to take measures during sexual activity to deal with SCI effects such as weakness and movement limitations, and to avoid injuries such as skin damage in areas of reduced sensation. Education and counseling about sexuality is an important part of SCI rehabilitation but is often missing or insufficient. Rehabilitation for children and adolescents aims to promote the healthy development of sexuality and includes education for them and their families. Culturally inherited biases and stereotypes negatively affect people with SCI, particularly when held by professional caregivers. Body image and other insecurities affect sexual function and have profound repercussions on self-esteem and self-concept. SCI causes difficulties in romantic partnerships, due to problems with sexual function and to other stresses introduced by the injury and disability, but many of those with SCI have fulfilling relationships and marriages. Relationships, self-esteem, and reproductive ability are all aspects of sexuality, which encompasses not just sexual practices but a complex array of factors: cultural, social, psychological, and emotional influences.
Sexuality and identity
Sexuality is an important part of each person's identity, although some people might have no interest in sex. Sexuality has biological, psychological, emotional, spiritual, social, and cultural aspects. It involves not only sexual behaviors but relationships, self-image, sex drive, reproduction, sexual orientation, and gender expression. Each person's sexuality is influenced by lifelong socialization, in which factors such as religious and cultural background play a part, and is expressed in self-esteem and the beliefs one holds about oneself (identifying as a certain gender, or as an attractive person).
SCI is extremely disruptive to sexuality, and it most frequently happens to young people, who are at a peak in their sexual and reproductive lives. Yet the importance of sexuality as a part of life is not diminished by a disabling injury. Although for years people with SCI were believed to be asexual, research has shown sexuality to be a high priority for people with SCI and an important aspect of quality of life. In fact, of all abilities they would like to have return, most paraplegics rated sexual function as their top priority, and most tetraplegics rated it second, after hand and arm function. Sexual function has a profound impact on self-esteem and adjustment to life post-injury. People who are able to adapt to their changed bodies and to have satisfying sex lives have better overall quality of life.
Sexual function SCI usually causes sexual dysfunction, due to problems with sensation and the body's arousal responses. The ability to experience sexual pleasure and orgasm are among the top priorities for sexual rehabilitation among injured people.
Much research has been done into erection. By two years post-injury, 80% of men recover at least partial erectile function, though many experience problems with the reliability and duration of their erections if they do not use interventions to enhance them. Studies have found that half or up to 65% of men with SCI have orgasms, although the experience may feel different than it did before the injury. Most men say it feels weaker, and takes longer and more stimulation to achieve.
Common problems women experience post-SCI are pain with intercourse and difficulty achieving orgasm. Around half of women with SCI are able to reach orgasm, usually when their genitals are stimulated. Some women report the sensation of orgasm to be the same as before the injury, and others say the sensation is reduced.
Complete and incomplete injury The severity of the injury is an important aspect in determining how much sexual function returns as a person recovers. According to the American Spinal Injury Association grading scale, an incomplete SCI is one in which some amount of sensation or motor function is preserved in the rectum. This indicates that the brain can still send and receive some messages to the lowest parts of the spinal cord, beyond the damaged area. In people with incomplete injury, some or all of the spinal tracts involved in sexual responses remain intact, allowing, for example, orgasms like those of uninjured people. In men, having an incomplete injury improves chances of being able to achieve erections and orgasms over those with complete injuries.
Even people with complete SCI, in whom the spinal cord cannot transmit any messages past the level of the lesion, can achieve orgasm. In 1960, in one of the earliest studies to look at orgasm and SCI, the term phantom orgasm was coined to describe women's perception of orgasmic sensations despite SCI—but subsequent studies have suggested the experience is not merely psychological. Men with complete SCI report sexual sensations at the time of ejaculation, accompanied by physical signs normally found at orgasm, such as increased blood pressure. Women can experience orgasm with vibration to the cervix regardless of level or completeness of injury; the sensation is the same as uninjured women experience.
The peripheral nerves of the parasympathetic nervous system that carry messages to the brain (afferent nerve fibers) may explain why people with complete SCI feel sexual and climactic sensations. One proposed explanation for orgasm in women despite complete SCI is that the vagus nerve bypasses the spinal cord and carries sensory information from the genitals directly to the brain. Women with complete injuries can achieve sexual arousal and orgasm through stimulation of the clitoris, cervix, or vagina, which are each innervated by different nerve pathways, which suggests that even if SCI interferes with one area, the function might be preserved in others. In both injured and uninjured people, the brain is responsible for the way sensations of climax are perceived: the qualitative experiences associated with climax are modulated by the brain, rather than a specific area of the body.
Level of injury
In addition to completeness of injury, the location of the damage on the spinal cord influences how much sexual function is retained or regained after injury. Injuries can occur in the cervical (neck), thoracic (back), lumbar (lower back), or sacral (pelvic) levels. Between each pair of vertebrae, spinal nerves branch off of the spinal cord and carry information to and from specific parts of the body. The location of injury to the spinal cord maps to the body, and the area of skin innervated by a specific spinal nerve is called a dermatome. All dermatomes below the level of injury to the spinal cord may lose sensation.
An injury at a lower point on the spine does not necessarily mean better sexual function; for example, people with injuries in the sacral region are less likely to be able to orgasm than those with injuries higher on the spine. Women with injuries above the sacral level have a greater likelihood of orgasm in response to stimulation of the clitoris than those with sacral injuries (59% vs 17%). In men, injuries above the sacral level are associated with better function in terms of erections and ejaculation, and fewer and less severe reports of dysfunction. This may be due to reflexes that do not require input from the brain, which sacral injuries might interrupt.
Psychogenic and reflexogenic responses The body's physical arousal response (vaginal lubrication and engorgement of the clitoris in women and erection in men) occurs due to two separate pathways which normally work together: psychogenic and reflex. Arousal due to fantasies, visual input, or other mental stimulation is a psychogenic sexual experience, and arousal resulting from physical contact to the genital area is reflexogenic. In psychogenic arousal, messages travel from the brain via the spinal cord to the nerves in the genital area. The psychogenic pathway is served by the spinal cord at levels T11–L2. Thus people injured above the level of the T11 vertebra do not usually experience psychogenic erection or vaginal lubrication, but those with an injury below T12 can. Even without these physical responses, people with SCI often feel aroused, just as uninjured people do. The ability to feel the sensation of a pinprick and light touch in the dermatomes for T11–L2 predicts how well the ability to have psychogenic arousal is preserved in both sexes. Input from the psychogenic pathway is sympathetic, and most of the time it sends inhibitory signals that prevent the physical arousal response; in response to sexual stimulation, excitatory signals are increased and inhibition is reduced. Removing the inhibition that is normally present allows the spinal reflexes that trigger the arousal response to take effect.
The reflexogenic pathway activates the parasympathetic nervous system in response to the sensation of touch. It is mediated by a reflex arc that goes to the spinal cord (not to the brain) and is served by the sacral segments of the spinal cord at S2–S4. A woman with a spinal cord lesion above T11 may not be able to experience psychogenic vaginal lubrication, but may still have reflex lubrication if her sacral segments are uninjured. Likewise, although a man's ability to get a psychogenic erection when mentally aroused may be impaired after a higher-level SCI, he may still be able to get a reflex or "spontaneous" erection. These erections may result in the absence of psychological arousal when the penis is touched or brushed, e.g. by clothing, but they do not last long and are generally lost when the stimulus is removed. Reflex erections may increase in frequency after SCI, due to the loss of inhibitory input from the brain that would suppress the response in an uninjured man. Conversely, an injury below the S1 level impairs reflex erections but not psychogenic erections. People who have some preservation of sensation in the dermatomes at the S4 and S5 levels and display a bulbocavernosus reflex (contraction of the pelvic floor in response to pressure on the clitoris or glans penis) are usually able to experience reflex erections or lubrication. Like other reflexes, reflexive sexual responses may be lost immediately after injury but return over time as the individual recovers from spinal shock.
Factors in reduced function