A Kinematic Symmetry Index of Gait Patterns Between Older Adults With and Without Low Back Pain.

STUDY DESIGN: Cross-sectional study.

OBJECTIVE: To investigate the symmetry index for limb support patterns in right limb-dominant older adults with and without low back pain (LBP).

SUMMARY OF BACKGROUND DATA: The effects of bilateral asymmetry on gait performance were reported; however, there is a lack of understanding on kinematic symmetry to assess subjects with LBP. This asymmetry might be related to increased compensatory patterns to the dominant side in subjects with LBP.

METHODS: Eighty-two right limb-dominant older adults (45 control subjects and 37 subjects with LBP) participated in the study. A three-dimensional motion capture system was used to measure temporal-spatial gait parameters (cadence, speed, stride length, step length, and limb support times). The symmetry index was the ratio of the gait cycle between the limbs to compare the dominance pattern between groups.

RESULTS: Although the symmetry index was not different between groups, the initial limb support (t = 2.07, P = 0.04) and terminal limb support (t = -2.26, P = 0.02) times were significantly different. The LBP group demonstrated significantly greater nondominant initial support times and dominant terminal support times. The single-limb support was not different between groups (t = 1.72, P = 0.09). The limb support pattern demonstrated a significant interaction between groups (F = 4.72, P = 0.03) regardless of gait speed (F = 0.91, P = 0.34).

CONCLUSION: An asymmetrical gait pattern was evident in the LBP group as they demonstrated a longer double-limb support pattern due to a possible pain avoidance strategy. The control group demonstrated a symmetrical pattern for limb support in the stance phase. Clinicians need to consider asymmetric limb support patterns of gait modification similar to the control group when developing rehabilitation strategies for patients with LBP.

LEVEL OF EVIDENCE: 3.