Spinal shrinkage and recovery in women with and without low back pain.

Abstract

To assess the behavior of the spinal column after loading in participants with and without low back pain (LBP) using spinal shrinkage measurements as a criterion and to analyze the relations among spinal shrinkage, recovery, and LBP. A case-control study with repeated measures. University department with recruitment from primary care. Convenience sample of 31 women (15 with chronic, nondisabling LBP [LBP group]; 16 with no history of low back disorders [control group]). Not applicable. Changes in body length as determined by using a stadiometer. The spinal shrinkage induced by the exercise was similar ( P >.05) in both groups (control group, mean +/- standard deviation of -3.99+/-1.13 mm; LBP group, -4.16+/-1.54 mm). Differences in spinal length were found after 20 minutes in the recovery position ( P <.05). The control group was able to recover stature to a greater extent (111.2%+/-13.6%) than the LBP group ( P <.05), which was unable to regain stature beyond baseline (57.5%+/-25.1%). A negative correlation was found between regaining stature and low back pain ( r =-.52, P <.05). Participants with LBP were unable to recover stature to the same extent as controls. We suggest that LBP is related to the diminished ability to recover rather than to the magnitude of the spinal shrinkage imposed during the task.