Thoracic Kyphosis and Lumbar Lordosis Assessment by Radiography and Photogrammetry: A Review of Normative Values and Reliability

The purpose of this study was to review referential values for thoracic kyphosis and lumbar lordosis for radiography and photogrammetry analysis and search for information about the interrater and intrarater reliability. The databases PubMed/Medline and LILACS were searched using the following keywords: radiograph and posture, postural alignment, and photogrammetry or photometry or biophotogrammetry. Studies containing values of thoracic kyphosis and lumbar lordosis or a reliability test assessed by radiography and photogrammetry were selected. Random numbers were generated in MATLAB from each study individually to establish normative values for the thoracic kyphosis and lumbar lordosis for both methods. After that, frequencies (median, first quartile, and third quartile) were obtained in SPSS 20.0 (IBM Corp, Armonk, New York). Twenty-six articles were selected, of which 23 studies contained values for thoracic kyphosis and lumbar lordosis and 10 tested the intra- and interrater reliability of both methods. For the studies with radiography that calculated the angle by the same method of assessment, the mean was 44.07° (4.75) for L1 to L5 and 58.01° (5.75) for L1 to S1, and for T1 to T12 the mean was 48.33° (6.24). Most studies used the intraclass correlation coefficient test, showing strong reliability. No concordance among the results for both methods was shown. Also, it was not possible to perform the same procedure with the photogrammetry studies because of the great discrepancy in procedures and angle calculations. To assess the reliability, it is necessary to use the proper statistical test.