Establishing the validity of surface topography for assessment of scoliosis: a prospective study.

STUDY DESIGN

Descriptive survey.

OBJECTIVES

Compare radiographic parameters measured using surface topography (ST) with those obtained radiographically to determine the validity of ST for scoliotic assessment.

METHODS

While anterior-posterior radiography is the gold standard for diagnosing scoliosis, repeated radiographic use is associated with increased carcinogenicity. Studies have thus focused on radiation-free systems, including ST, to calculate the scoliotic angle. Seventeen patients ages 25-76 were included. Each patient received one AP radiograph and three repeated ST measurements over two months. Values were analyzed by two raters to determine comparability between ST and radiographic measurements. Interobserver reliability (ICC) was calculated and statistical significance was determined by the p-value of a paired two-tailed t-test.

RESULTS

ICC showed excellent reliability (> 0.90). There was no significant difference (p > 0.40) in apical vertebral deviation/translation between conventional radiography (0.9 ± 0.8) and ST (1.2 ± 1.0). There was no significant difference (p > 0.30) in sagittal balance radiographic (4.0 ± 3.1) and ST (4.4 ± 3.3), and coronal balance radiographic (1.4 ± 1.3) and ST (1.1 ± 1.1) measurements. Significant difference (p < .001) was found between lumbar lordosis radiographic (52.6 ± 18.4) and ST (37.9 ± 16.6), kyphotic angle radiographic (35.1 ± 16.0) and ST (50.0 ± 11.9), and scoliotic angle radiographic (11.3 ± 12.4) and ST (17.7 ± 10.2) measurements.

CONCLUSIONS

No significant difference was observed between various ST and radiographic measurements, including apical vertebral deviation, sagittal balance, and coronal balance. While a larger prospective study is needed to further assess the validity of ST, these initial measurements suggest the possibility of an effective and radiation-free adjunctive method of assessing balance in the coronal plane.