Can tri-axial accelerometers be used to improve current clinical measures of spinal mobility in patients with axial spondyloarthritis?

Abstract

Background: Spinal mobility limitation is a characteristic feature in Axial Spondyloarthritis (AxSpA). Current clinical measurements of spinal mobility have shown low criterion-concurrent validity. This thesis sought to determine criterion-concurrent validity for a new, and clinically feasible, measurement of spinal mobility in AxSpA patients using tri-axial accelerometers. Methods: Two perpendicular upright reference radiographs were taken followed by three flexion trials. For all postures, three measurements were taken: clinical tape, followed immediately by synchronized radiograph and accelerometer at the end ranges of forward and bilateral flexion. Results: In forward bending, accelerometers (r=0.590, p=0.010) had a stronger correlation to radiographs than all three tape measures. In lateral bending, the Lateral Spinal Flexion (r=0.743, p=0.001) and Domjan tape measure (r=0.708, p=0.002) correlated stronger with radiograph than the accelerometer method (r=0.556, p=0.016). Conclusion: The accelerometer measure is superior to current tape measures of spinal mobility in forward bending; but is outperformed in that respect by the LSF and Domjan clinical tests. Further evaluation of accelerometer and tape methods in early stage spinal mobility assessment is warranted.