The pain can present acutely but in some cases can persist, leading to chronic pain. Chronic back pain in people with otherwise normal scans can result from central sensitization, in which an initial injury causes a longer-lasting state of heightened sensitivity to pain. This persistent state maintains pain even after the initial injury has healed. Treatment of sensitization may involve low doses of antidepressants and directed rehabilitation such as physical therapy. Spinal disc disease
Spinal disc disease occurs when the nucleus pulposus, a gel-like material in the inner core of the vertebral disc, ruptures. Rupturing of the nucleus pulposus can lead to compression of nerve roots. Symptoms may be unilateral or bilateral, and correlate to the region of the spine affected. The most common region for spinal disk disease is at L4–L5 or L5–S1. The risk for lumbar disc disease is increased in overweight individuals because of the increased compressive force on the nucleus pulposus, and is twice as likely to occur in men. A 2002 study found that lifestyle factors such as night-shift work and lack of physical activity can also increase the risk of lumbar disc disease. Severe spinal-cord compression is considered a surgical emergency and requires decompression to preserve motor and sensory function. Cauda equina syndrome involves severe compression of the cauda equina and presents initially with pain followed by motor and sensory. Bladder incontinence is seen in later stages of cauda equina syndrome.
Several studies, but not all, found age to be a significant factor: adolescents and young adults in the normal population reported the highest rate. In a study, 46% of college students reported at least one significant episode in the previous year. In another study, 20% of patients with minor head injury experience significant depersonalization and derealization. Several studies found that up to 66% of individuals in life-threatening accidents report transient depersonalization at minimum during or immediately after the accidents. Depersonalization occurs 2-4 times more in women than in men.A similar and overlapping concept called ipseity disturbance (ipse is Latin for "self" or "itself") may be part of the core process of schizophrenia spectrum disorders. However, specific to the schizophrenia spectrum seems to be "a dislocation of first-person perspective such that self and other or self and world may seem to be non-distinguishable, or in which the individual self or field of consciousness takes on an inordinate significance in relation to the objective or intersubjective world" (emphasis in original).For the purposes of evaluation and measurement depersonalization can be conceived of as a construct and scales are now available to map its dimensions in time and space. A study of undergraduate students found that individuals high on the depersonalization/derealization subscale of the Dissociative Experiences Scale exhibited a more pronounced cortisol response in stress.