Electromyographic recordings of low back pain subjects and non-pain controls in six different positions: effect of pain levels.

Surface electromyographic (EMG) activity recordings of bilateral paraspinal muscle tension were measured twice on 20 non-pain controls and on 46 low back pain subjects (21 individuals with intervertebral disk disorders and 25 subjects with unspecified musculoskeletal backache) during 6 positions: standing, bending from the waist, rising, sitting with back unsupported, sitting with back supported, and prone. Back pain subjects were measured during both low pain and high pain states. Results revealed a non-significant trend for all subjects, regardless of diagnosis, to have higher paraspinal muscle tension levels on the second (or high pain) assessment.

Electromyographic recordings of 5 types of low back pain subjects and non-pain controls in different positions.

Surface EMG recordings of bilateral paraspinal muscle tension were measured on 207 subjects (29 non-back pain controls, 20 individuals with spondyloarthritis, 52 with intervertebral disk disorders, 66 with unspecified musculoskeletal backache, 17 with some combination of the above 3 groups and 23 subjects with other types of back pain, including unknown, scoliosis and psychogenic) in 6 positions: standing, bending from the waist, rising, sitting with back unsupported, sitting with back supported and prone. Results of both individual and group analyses revealed a significant main effect of diagnosis. Post hoc analyses (Duncan's) revealed controls to have significantly lower overall EMG levels than the intervertebral disk disorders and unspecified musculoskeletal backache groups.

Psychological factors influencing chronic phantom limb pain: an analysis of the literature.

The behavioral literature concerning chronic phantom limb pain was reanalyzed in order to determine the role of psychological factors in initiating and controlling the intensity of its episodes. Some of the behavioral literature presents an inaccurate picture of amputees who have phantom pain. This apparently happened because many of the data were gathered from those amputees requesting treatment for phantom pain who were referred to mental health professionals.