Variations in balance and body sway in middle-aged adults. Subjects with healthy backs compared with subjects with low-back dysfunction.

In a preliminary investigation of 45 middle aged adult subjects, 20 with low-back pain (LBP) and 25 with healthy backs (HB), balance responses (body sway) were measured under different sensory conditions with computerized force plate stabilometry. Compared with HB subjects, in the most stable and then the least stable balance positions, the LBP subjects demonstrated significantly greater postural sway, kept their center of force (COF) significantly more posterior, and were significantly less likely to be able to balance on one foot with eyes closed. Based on subjective observations, the LBP subjects were more likely to fulcrum about the hip and back to maintain uprightness in challenging balance tasks compared with healthy controls who maintained their fulcrum for the COF around the ankle. Research is needed to determine the incidence of balance problems in LBP patients compared with controls. Effective physical therapy assessment and treatment of LBP patients may require attention to postural alignment, strength, flexibility, joint stability, balance reactions, and postural strategies.