Pathogenesis Of Back Pain Research Articles

Henry Vernon Crock

Henry Vernon Crock (“Harry”) was a brilliantly innovative spinal surgeon, whose detailed investigations of the blood supply to the spinal cord drew attention to its crucial role in the pathogenesis...

Pathophysiology of Low Back Pain during Exposure to Microgravity

Astronauts exposed to microgravity frequently report low back pain. This pain is described as moderate to severe in intensity. This condition warrants investigation as low back pain may hinder an astronaut's ability to perform challenging tasks by virtue of disruption of sleep and, subsequently, mental concentration. It is reported by astronauts that a "fetal tuck position" described as knees to chest position relieves back pain. It is possible that the pathogenesis of back pain in microgravity is discogenic (or mechanical) and somatic, referred from the sinuvertebral nerves due to excessive expansion of the lumbar intervertebral discs associated with reduction of gravitational compressive loads in space. The fetal tuck position may increase lumbar intervertebral disc hydrostatic pressure by flexion and transfer of spinal compressive forces toward the anterior region of the lumbar discs, subsequently reducing disc volume. Moreover, this position may reduce Type IV mechanoreceptor facilitation and nerve impulse propagation from the sinuvertebral nerves of the annulus fibrosus, and thus diminish low back pain perception. Elongated posterior soft tissues (apophyseal joint capsules and ligaments) with spinal flexion may potentially stimulate Type I and II mechanoreceptors. This neutralizes substance P in the spinal cord dorsal horn by increasing naturally occurring opioids such as enkephalins. Separately, other investigators have reported a higher incidence of herniated discs (HNP) in astronauts postflight. Further studies of countermeasures are recommended to prevent excessive spinal elongation and disc expansion, reduce low back pain in microgravity, and simulate 1-G disc homeostasis, which may also help prevent HNPs postflight.

Back pain in osteoporotic vertebral fractures

This review article examines the epidemiology and pathogenesis of back pain and vertebral fractures in osteoporosis, reviewing the management of pain in patients with vertebral fractures and the direct and indirect effect of osteoporosis treatments on back pain. The management of patients with vertebral fractures has largely concentrated on the prevention of further fractures by the treatment of underlying osteoporosis, with drug treatment for acute and chronic back pain and the non-pharmacological management of vertebral fractures receiving less attention. Emerging evidence suggests that, in addition to reducing the incidence of vertebral fractures, calcitonin, intravenous bisphosphonates and teriparatide may also have a direct effect on bone pain. Targeted analgesia, tailored to individual need is often required in both the acute and chronic phases following vertebral fracture. Vertebroplasty and kyphoplasty have also been approved for use in the management of vertebral fractures and may prove useful in selected patients unresponsive to conventional pain relief. There is some evidence to support the use of individualised tailored exercise programmes aimed at strengthening back muscles to maintain bone density and reduce further fracture incidence. In addition the use of specific orthoses may help to reduce kyphosis, improve mobility and reduce pain. Chronic back pain associated with vertebral fracture provides a great challenge to health care professionals and the patient. This demands a combination of options, including not only therapeutic interventions, but also physiotherapy, psychological support and patient education.

Epidural neuroplasty

Epidural neuroplasty is an interventional pain management technique used to rreat pain originating from structures within or adjacent to the epidural space or in the intervertebral foramen at all segmental levels. The technique is based on sound scientific foundations that include substantial knowledge regarding the pathogenesis of back pain and radiculopathy. For the technique to be safe and for maximization of therapeutic benefit, strict adherence to the details (technique, patient selection) described here is recommended.

IgG and IgM concentration in the prolapsed human intervertebral disc and sciatica etiology.

A prospective study was conducted in patients who underwent surgeries for sciatica. The results were compared to those of control subjects. This study expanded knowledge about the pathogenesis of back pain and sciatica in disc herniation. Nucleus pulposus, retrieved from 10 patients who underwent surgeries for sciatica caused by disc herniation and from 8 patients used as control subjects, was homogenized and together with serum and cerebrospinal fluid was examined for local production of IgG and IgM by rate nephelometry. Experimental data have shown an inflammatory reaction in the nucleus pulposus of animal models. An increased ratio IgGNP/IgGs x 10(3) and IgMNP/IgMs x 10(3) was found in all patient samples, whereas only the IgMNP/IgMs x 10(3) ratio was significantly higher (P < 0.005) when compared with those of the control values. These findings may be secondary to an inflammatory reaction close to the nerve root and prolapsed nucleus pulposus. Therefore, they may contribute in some way to the inflammatory origin of sciatica.

Life Events and Psychological Disturbance in Patients with Low-Back Pain

To elucidate the possible contribution of psychologic factors in the pathogenesis of back pain, an assessment of life events and psychiatric symptoms was undertaken in 80 new referrals. In 57, the back pain had a definite onset recent enough to allow this to be dated accurately; these definite onset cases were divided into 26 in whom a specific organic diagnosis could be made and 31 in whom the cause of the pain was uncertain. An additional 23 patients had chronic pain, or could not date the onset of their symptoms. Unlike previous studies, events that occurred after the onset of back pain and thus could have been a consequence of the back pain were excluded. Before onset of back pain there was a significant excess of adverse life events in those with definite onset back pain of uncertain cause, compared with those with a specific diagnosis: there was no such excess in the periods before referral and attendance at the clinic. Diagnosable psychiatric illness was virtually confined to those with chronic pain. These findings indicate that stress, but not psychiatric illness, is involved in the onset of back pain. Further research is now required to ascertain whether those patients who have many psychiatric symptoms at the time of onset are those who develop chronic pain.