A comparative evaluation of the AOFAS Ankle-Hindfoot Scale and the Foot Function Index using the Oxford Foot Model

Introduction: The NeuroFlexor® is an apparatus that estimates the viscosity, elasticity and the neural component of the resistance in the wrist and finger flexor muscles when the wrist is passively extended. Only the neural component has been validated, and the device has not been used in children. It is proposed that viscosity and elasticity increase with increased muscle cross-sectional area. The aim of the study was to correlate the cross-sectional areas ofwrist and finger flexormuscleswith viscosity and elasticitymeasured with the NeuroFlexor®, and with grip strength. Patients/materials and methods: 15 typically developed subjects, 8–18 years old and one subject with cerebral palsy (CP), 17 years old, were testedwith theNeuroFlexor®. Ultrasoundwas used to obtain the cross-sectional areas of the flexor carpi radialis and flexor digitorum superficialismuscles. Grip strengthwasmeasured with the Grippit®. Results: There were moderate correlations between the viscosity and the cross sectional areas of the flexor carpi radialis (rrho=0.57; p=0.03) and the flexor digitorum superficialis (rrho=0.57; p=0.03). There were no correlations between elasticity and the flexor carpi radialis (rrho=0.30; p=0.28) and flexor digitorum superficialis (rrho=0.28; p=0.33). Discussion and conclusions: The current pilot study suggests that the NeuroFlexor® estimates viscosity correctly. The NeuroFlexor® has the potential to become a useful tool for treatment evaluation in children with CP and contribute to the understanding of contractures.