Study design: Retrospective, observational study.

Objectives: This study aimed to examine the association between spinopelvic parameters and balance function in low back pain (LBP).

Methods: Among patients in the rehabilitation medicine department, the data of 182 patients (mean age, 47.8 years; M/F = 64/118) was obtained retrospectively. Spinopelvic parameters were measured through a whole-body low-dose biplanar radiography using the EOS imaging system, and balance function was evaluated by the center of pressure (COP) movement using the Zebris treadmill system. Pearson correlations were used to determine the relationship between radiographic and balance function. Stepwise multiple linear regression analyses were conducted with the balance function as a dependent variable and age and spinopelvic parameters as independent variables.

Results: Increased age, knee flexion (KF), pelvic tilt (PT), C7-central sacral line (C7-CSL) and C7 sagittal vertical axis (SVA), and decreased spino-sacral angle (SSA) were associated with both poor static and dynamic balance. Moreover, increased Cobb's angle and decreased thoracic kyphosis (TK) and lumbar lordosis (LL) was associated with poor static balance. Increased pelvic incidence (PI) was related to poor dynamic balance. Increased age, Cobb's angle, SVA, and decreased TK were risk factors for poor static balance. For dynamic balance, increased age, C7-CSL, and PT were risk factors for poor sagittal balance, whereas increased CAM-plumb line and PT were risk factors for poor coronal balance.

Conclusions: Balance function was associated with spinopelvic parameters in patients with LBP. Increased SVA, followed by increased PT, was the strongest independent factor associated with poor static and dynamic balance.