Lightning Podiums: Value and Outcomes in Spinal Surgery - Room 801B

Presented by: I. Lieberman


R. Haddas(1), I. Lieberman(2)

(1) Texas Back Institute, Research Foundation, Plano, TX, United States
(2) Texas Back Institute, Plano, TX, United States


Introduction: Patients with adult degenerative scoliosis (ADS) demonstrate an altered balance. Balance is defined as the ability of the human body to maintain its center of mass (COM) within the base of support with minimal postural sway. Sway is the movement of the COM in the horizontal plane when a person is standing in a static position. Self-reported measures are routinely used in the clinical setting to capture data related to back and leg pain symptoms, function and perceived disability, in the setting of adult degenerative scoliosis. However, few studies have examined the correlation between patients' self-reported clinical outcome and objective biomechanical balance analysis. The purpose of this study was to determine the correlation between self-reported assessments of function with objective biomechanical measures of function.

Methods: Data were prospectively collected from patients (N=30) with symptomatic ADS who were deemed appropriate surgical candidates. Functional balance analysis was performed the week before surgery. The functional balance test was similar to a Romberg´s test in which the patients were required to stand erect with their feet together and eyes open in their self-perceived balanced and natural position for a full minute. COM and head displacements in the sagittal and coronal planes during the functional balance test were calculated using a custom algorithm. We further measured and calculated total sway amount by the overall length of the COM displacement line in the horizontal plane in all directions. Furthermore, back pain and leg pain Visual Analogue Scale (VAS), and Oswestry Disability Index (ODI) scores were obtained on the same day of testing. Correlations were determined between the self-report clinical outcome questionnaire measures and objective balance analysis biomechanical data using Pearson´s Product Correlation in SPSS.

Results: The ODI was correlated with horizontal COM sway in the sagittal (r=0.53, p=0.003) and coronal (r=0.42, p=0.023) planes, and COM total sway (r=0.52, p=0.004). Furthermore, ODI was correlated with horizontal head sway in the sagittal (r=0.43, p=0.021) and coronal (r=0.36, p=0.050) planes, and head total sway(r=0.37, p=0.049). The ODI standing question was correlated with COM total sway (r=0.44, p=0.017), horizontal head sway in the sagittal (r=0.39, p=0.036) and coronal (r=0.36, p=0.050) planes, and head total sway(r=0.41, p=0.028). The leg VAS was correlated with COM total sway (r=-0.33, p=0.050). The back VAS was not correlated with any functional balance parameters.

Discussion: This study demonstrated a strong correlation between biomechanical parameters as measured with objective balance analysis and functional disability as measured with patient reported outcome measures including the VAS and ODI. Functional balance analysis can be a useful tool to evaluate patients with spine deformity and to assess the outcomes of treatment in this group of patients. Objective motor performance measures will improve the evaluation and understanding of the biomechanical effects of spinal disorders on locomotion. Functional balance and disability are strongly correlated in surgical ADS patients.