The effect of lifting and lowering an external load on repositioning error of trunk flexion-extension in subjects with and without low back pain.

OBJECTIVE

To determine whether the repositioning error of trunk flexion-extension in individuals with low back pain is different from that in those not experiencing low back pain when lifting and lowering external loads.

DESIGN

A case-control study.

SETTING

Physical therapy department of a medical centre.

SUBJECTS

Twenty subjects with subacute low back pain and 20 control subjects without low back pain.

INTERVENTIONS

Tasks with and without lifting and lowering an external load.

MAIN OUTCOME MEASURES

The trunk repositioning errors were measured with Measurand Shape Tape.

RESULTS

In subjects with low back pain, trunk repositioning errors were significantly reduced when lifting and lowering an external load in the direction of flexion (3.77 +/- 1.26 degrees in a loaded condition versus 4.82 +/- 2.97 degrees in an unloaded condition; P < 0.05) and extension (3.17 +/- 2.15 degrees in a loaded condition versus 5.03 +/- 3.74 degrees in an unloaded condition; P < 0.05). In control subjects, trunk repositioning errors were not significantly changed when lifting and lowering an external load in the direction of flexion (2.80 +/- 1.39 degrees in a loaded condition versus 2.63 +/- 1.24 degrees in an unloaded condition; P > 0.05) and extension (2.87 +/- 11.40 degrees in a loaded condition versus 3.15 +/- 11.50 degrees in an unloaded condition; P > 0.05). The direction of motion (trunk flexion or extension) was not shown to be significant in this study.

CONCLUSION

Performing the task whilst lifting or lowering a submaximal load showed a reduced trunk repositioning error in subjects with subacute low back pain. Lifting and lowering a submaximal load might be considered as one of the rehabilitative strategies to hasten a return to work.