The proprioceptive system helps the spine assume an exact position when moving from one position to another. Studies show that this repositioning mechanism is altered in patients with chronic neck pain. But what happens with patients who have chronic low back pain (LBP)?
In this study, a repositioning test is used to see if this mechanism is disturbed in LBP patients. Patients with LBP for more than six months were compared to healthy adults the same age without back pain.
An electromagnetic tracking system was used to record the position of the spine. Each person in the study was seated on a stool in a straight spine position. The pelvis was tilted forward slightly. After bending forward, the subjects were asked to sit up and assume the target (upright) position. Everyone wore a blindfold to keep them from using their vision to return to the exact position.
The authors report that there were no differences in repositioning errors between the healthy group and the group with LBP. This suggests that abnormal sensory cues aren’t measurable with this test.
The repositioning test may not be the best measure of changes in proprioception that can occur with LBP. More study is needed to find a test of sensorimotor dysfunction in chronic LBP patients. Once the abnormal sensory cues can be measured, a rehab program to address the problem can be designed.