Normative NeuroFlexor data for detection of spasticity after stroke: a cross-sectional study

J Neuroeng Rehabil. 2016 Mar 18;13:30. doi: 10.1186/s12984-016-0133-x.


Background and objective: The NeuroFlexor is a novel instrument for quantification of neural, viscous and elastic components of passive movement resistance. The aim of this study was to provide normative data and cut-off values from healthy subjects and to use these to explore signs of spasticity at the wrist and fingers in patients recovering from stroke.

Methods: 107 healthy subjects (age range 28-68 years; 51 % females) and 39 stroke patients (age range 33-69 years; 33 % females), 2-4 weeks after stroke, were assessed with the NeuroFlexor. Cut-off values based on mean + 3SD of the reference data were calculated. In patients, the modified Ashworth scale (MAS) was also applied.

Results: In healthy subjects, neural component was 0.8 ± 0.9 N (mean ± SD), elastic component was 2.7 ± 1.1 N, viscous component was 0.3 ± 0.3 N and resting tension was 5.9 ± 1 N. Age only correlated with elastic component (r = -0.3, p = 0.01). Elasticity and resting tension were higher in males compared to females (p = 0.001) and both correlated positively with height (p = 0.01). Values above healthy population cut-off were observed in 16 patients (41 %) for neural component, in 2 (5 %) for elastic component and in 23 (59 %) for viscous component. Neural component above cut-off did not correspond well to MAS ratings. Ten patients with MAS = 0 had neural component values above cut-off and five patients with MAS ≥ 1 had neural component within normal range.

Conclusion: This study provides NeuroFlexor cut-off values that are useful for detection of spasticity in the early phase after stroke.

Keywords: Biomechanics; Muscle spasticity; Normative data; Stroke; Upper extremity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Accelerometry / instrumentation*
  • Adult
  • Aged
  • Cross-Sectional Studies
  • Female
  • Humans
  • Male
  • Middle Aged
  • Movement / physiology
  • Muscle Spasticity / diagnosis*
  • Muscle Spasticity / etiology
  • Stroke / complications*