Validation of the walking index for spinal cord injury in a US and European clinical population

Abstract

To demonstrate the prospective construct validity of the walking index for spinal cord injury (WISCI) in US/European clinical population. Prospective Cohort in Denmark, Germany, Italy and the USA. PARTICIPANTS/METHOD: Participants with acute complete/incomplete (ASIA Impairment Scale (AIS) A, B, C and D) traumatic spinal cord injuries were enrolled from four centers. Lower extremity motor scores (LEMS), WISCI level and Locomotor Functional Independence Measure (LFIM) levels were assessed with change in ambulatory status. WISCI progression was assessed for monotonic direction of improvement (MDI). LEMS were correlated to WISCI/LFIM. Use of walking aids/braces were analyzed. One hundred and seventy participants were enrolled and 20 excluded. Of the 150 participants (USA 112/150; Europe 38/150) (AIS A=59, B=19, C=32, D=40), LEMS and WISCI assessments were performed initially and at final assessment (3-12 months post injury) or until maximum WISCI score of 20. Eighty-five percent of motor complete (66/78) and 10% (7/72) of motor incomplete participants showed no progression (73/150). Of the remaining participants (77/150) who improved, 81% (62/77) showed MDI. However, the deviation from MDI occurred only at one time-point in 10/15 participants. LEMS correlated with WISCI at initial and final assessment (0.47 and 0.91 P<0.001). Parallel bar use differed between the US and Europe possibly due to patterns of care. Use of braces also differed. The results support the hierarchical ranking of the WISCI scale and the correlation of WISCI levels to impairment (LEMS) in a clinical setting of four nations. Differences in practice between the US and Europe need consideration in design of trials.