Epidemiology of Spinal Cord Injury 419Marital Status
Given the relatively young age at which most individuals
incur an SCI, most (53.5%) have never married at the time of
their injury. There is an increased rate of divorce among per-
sons with SCI in comparison with the general population
(DeVivo & Fine, 1985; DeVivo, Hawkins, Richards, & Go,
1995), and the dissolution of the marriage tends to occur
within a year following injury onset.
Etiology of Injury
Motor vehicle accidents, falls, and gunshot wounds are the
three leading causes of SCI in the United States (Nobunaga,
Go, & Karunas, 1999). Gender differentiates the next two
causes, with diving and motorcycle accidents rounding out
the top “ve causes in men, while medical procedures and div-
ing accidents are the next leading causes of SCI in women.
While increased age reduces the chance of SCI due to sport-
ing accidents or violent acts, it is a large contributor to spinal
cord injuries resulting from falls.
While motor vehicle accidents continue to be the primary
cause of SCI in individuals up to age 45 years, injuries re-
sulting from violence, primarily in the form of gunshot
wounds, showed a startling increase of 64% in the 25-year
period from 1973 to 1998. A slight decrease in violence-
related SCI has been noted for the period from 1989 to 1998.
Ethnicity-related differences in SCI etiology exist. Violence
accounts for 7% to 8% of SCIs in Caucasians and Native
Americans, 46% in African Americans, 43.8% in Hispanics,
and 22% in Asians. Research is needed to determine whether
ethnic classi“cation functions as a proxy for other variables
that may be involved.
Sexuality and Reproductive Health
Based on the type of injury incurred, sexual response„like
sensation, movement, and other body functions„will be af-
fected in a predictable manner (see Figure 18.1). Thus, it is
important to determine the level, degree of injury, and
whether the injury affected the upper or lower motor neuron
system. When addressing issues of sexual function, it is
important to identify the aspect of the sexual response on
which to focus: erectile dysfunction, ejaculation, lubrication,
or orgasm.
When diagnosing erectile dysfunction, it is important to
determine whether re”exogenic or psychogenic erections are
attainable. Re”exogenic erections occur as a result of stimu-
lation in the genital area. Psychogenic erections result from
cognitive stimulation. Men with complete UMN injuries
typically retain the ability to achieve re”exogenic erections
while those with incomplete UMN injuries retain abilities
for both re”exogenic and psychogenic erections. Men with
incomplete LMN injuries often have the ability to achieve
psychogenic erections with a partially preserved ability for
re”exogenic erections.
Ejaculation is a complex process that involves coor-
dination of the sympathetic, parasympathetic, and somatic
nervous systems affected by SCI. Retrograde ejaculation, a
common consequence of SCI, occurs when semen is directed
into the bladder as a result of lack of closure at the neck of the
bladder. Use of pharmacological agents, vibratory stimula-
tion, electroejaculation, and direct aspiration of seminal ”uid
are techniques employed to obtain sperm from men with SCI
who would like to father children. Men report experiencing
orgasm as similar, weaker, or different, and 38% of men
with complete SCI report the ability to achieve orgasms
(Alexander, Sipski, & Findley, 1993).
Although sexual desire decreases after SCI, most men
continue to express interest in sexual activity. It is important
to recognize that preservation of sensation is not necessary
for sexual excitement and that stimulation above the level of
injury tends to become hypersensitive and erogenous, con-
tributing to the experience. Although most individuals with
SCI resume sexual activity within a year of injury, there is a
concomitant decrease in frequency of events, as well as a de-
creased sense of satisfaction, which (Berkman, Weissman, &
Frielich, 1978) may be a result of decreased availability of
partners. While 99% of men identify penile-vaginal inter-
course as their favorite preinjury sexual activity, this “gure
drops to 16% postinjury. Oral sex, kissing, and hugging
become preferred activities following SCI.
Information regarding female sexual response has been
based largely on self-report. Vaginal lubrication is compara-
ble to male erection and complete UMN injuries retain the
ability for re”exogenic but not psychogenic lubrication
(Sipski, Alexander, & Rosen, 1995). Women with incomplete
UMN SCIs maintain the capacity to achieve re”exogenic and
possibly psychogenic lubrication. About 25% of women with
complete LMN SCIs experience psychogenic lubrication,
and about 95% of women with incomplete LMN SCIs can
continue experiencing both forms of lubrication. Sipski et al.
(1995) support the belief that women with incomplete UMN
SCIs can achieve psychogenic lubrication based on pinprick
sensation at T11...12 dermatomes (see Figure 18.1), and
women with incomplete UMN SCIs affecting sacral seg-
ments can retain re”exogenic lubrication.
About half of all women with SCI report the ability to
achieve orgasm (Charlifue, Gerhart, Menter, Whiteneck, &
Manley, 1992). Whipple, Gerdes, and Komisaruk (1996)