The Association of Fear of Movement and Postural Sway in People with Low Back Pain

Abstract

Background: Fear of movement is thought to interfere with the recovery from low back pain (LBP). To date, the relationship between fears and movement characteristics such as balance has not been adequately elucidated. Recent findings suggest that more specific fears need to be assessed and put in relation to a specific movement task. We propose that the fear to move the trunk in a certain direction is distinctly related to the amount of postural sway in different directions. Therefore, our aim was to investigate whether fear of movement in general and on a certain movement plane is related to postural sway. Methods: Data was collected from participants with LBP during two assessments approximately three weeks apart. Postural sway was measured with a force-platform during quiet standing with the eyes closed. Fear of movement was assessed with an abbreviated version of the Tampa Scale of Kinesiophobia (TSK-11) and custom items referring to fear from trunk movements on the sagittal and the frontal plane. Results: Based on data from 25 participants, fear of movement on the frontal plane was positively related to displacement on the sagittal and frontal plane and to velocity on the frontal plane (P=.04; P=.004; P=.002). Fear of movement on the sagittal plane was not associated with any direction specific measure of sway. A positive relation of the TSK-11 with velocity of the frontal plane (P=.008) was found, but no association with undirected measures of sway. Discussion: Fear of movement in the frontal plane may be especially relevant to postural sway under the investigated stance conditions. It is possible that fear of moving in the frontal plane could interfere with balance control at the hip, shifting the weight from side to side on the frontal plane to control balance. Conclusion: For the first time the directional relationship of fear of movement and postural sway was studied by investigating the postural sway with a force-platform. Fear of movement on the frontal plane was positively associated with several measures of postural sway.