Idiopathic low back pain and the therapeutic use of spinal manipulation make a significant impact clinically, socially, and financially. It has been estimated that more than 75 percent of us will experience low-back pain at some time in our lives costing an estimated $20-$50 billion annually. Recent findings from meta-analyses indicate that spinal manipulation can be recommended clinically for the treatment of acute and chronic idiopathic low back pain. Chiropractors deliver more than 90 percent of spinal manipulations performed in the United and annual expenditures on chiropractic services exceed $4.7 billion annually. Neither the causes of idiopathic low back pain nor the mechanisms underlying the physiological effects of spinal manipulation are well understood. Recent investigations by the applicant indicate that the mechanical history of a vertebra alters the sensitivity of lumbar paraspinal muscle spindles to subsequent vertebral movement. Muscle spindle discharge in response to vertebral gliding (translation) depended upon whether the vertebra had been previously held in a position that unloaded or loaded the spindle for as little as 5 seconds. We believe this novel finding in the spine is important because motion segments are continually subjected to passive forces that can fix their spatial orientation. The proposed experiments are based upon 3 hypotheses. (1) Sensitivity of paraspinal muscle spindles to vertebral translation increases when linear displacement of the vertebra has previously unloaded the paraspinal muscle spindle. (2) Sensitivity of paraspinal muscle spindles to vertebral translation decreases when linear displacement of the vertebra has previously loaded the paraspinal muscle spindle. (3) The therapeutic effects of spinal manipulation may be mediated, in part, by its ability to correct the positional-history-dependent changes in paraspinal muscle spindle sensitivity. History-dependent alterations in sensory feedback from paraspinal muscle spindles could lead to proprioceptive errors and adversely affect neural control of segmental motion. Knowledge of mechanical factors that affect sensory input from vertebral tissues will help provide a better understanding of the most appropriate preventive and therapeutic interventions for spinal care. Spinal manipulation is inherently a biomechanical intervention and the therapeutic successes of spinal manipulation for idiopathic low back pain may relate, in part, to the mechanical component of idiopathic low back.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
1R01NS046818-01
Application #
6596318
Study Section
Geriatrics and Rehabilitation Medicine (GRM)
Program Officer
Chen, Daofen
Project Start
2003-04-01
Project End
2007-03-31
Budget Start
2003-04-01
Budget End
2004-03-31
Support Year
1
Fiscal Year
2003
Total Cost
$277,651
Indirect Cost
Name
Palmer College of Chiropractic
Department
Type
Other Domestic Higher Education
DUNS #
075845834
City
Davenport
State
IA
Country
United States
Zip Code
52803
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Reed, William R; Cao, Dong-Yuan; Ge, Weiqing et al. (2013) Using vertebral movement and intact paraspinal muscles to determine the distribution of intrafusal fiber innervation of muscle spindle afferents in the anesthetized cat. Exp Brain Res 225:205-15
Cao, Dong-Yuan; Reed, William R; Long, Cynthia R et al. (2013) Effects of thrust amplitude and duration of high-velocity, low-amplitude spinal manipulation on lumbar muscle spindle responses to vertebral position and movement. J Manipulative Physiol Ther 36:68-77
Ge, Weiqing; Pickar, Joel G (2012) The decreased responsiveness of lumbar muscle spindles to a prior history of spinal muscle lengthening is graded with the magnitude of change in vertebral position. J Electromyogr Kinesiol 22:814-20
Ge, Weiqing; Cao, Dong-Yuan; Long, Cynthia R et al. (2011) Plane of vertebral movement eliciting muscle lengthening history in the low back influences the decrease in muscle spindle responsiveness of the cat. J Appl Physiol 111:1735-43
Cao, Dong-Yuan; Pickar, Joel G (2011) Lengthening but not shortening history of paraspinal muscle spindles in the low back alters their dynamic sensitivity. J Neurophysiol 105:434-41
Cao, Dong-Yuan; Pickar, Joel G (2009) Thoracolumbar fascia does not influence proprioceptive signaling from lumbar paraspinal muscle spindles in the cat. J Anat 215:417-24
Ge, Weiqing; Pickar, Joel G (2008) Time course for the development of muscle history in lumbar paraspinal muscle spindles arising from changes in vertebral position. Spine J 8:320-8
Ge, Weiqing; Long, Cynthia R; Pickar, Joel G (2005) Vertebral position alters paraspinal muscle spindle responsiveness in the feline spine: effect of positioning duration. J Physiol 569:655-65