Quantifying paretic upper limb impairment in stroke and cerebral palsy

Disability in upper extremity function, due to sensorimotor deficits and other
deficits, is a common problem for patients that suffered from a stroke and
adults with cerebral palsy (CP). This problem can lead to restricted mobility
of the upper extremity, resulting in an impact on the quality of life [1].
Clinical signs of impaired upper extremity function are muscle weaknesses due
to paresis or paralysis, abnormal reflex activity (spasticity), loss of
independent joint control (abnormal synergies) and changes in viscoelastic
properties (joint stiffness). Current clinical assessments to study these signs
include the Modified Ashworth scale and the Brunnstrom Fugl-Meyer scale.
However, such clinical assessments have limitations, such as a high observer
variability [2]. In order to improve treatment outcomes of upper extremity
function interventions, accurate diagnosis of the explanatory deficits is
needed. Previous studies already investigated assessment protocols to
distinguish some clinical signs/parameters with a neuromechanical model in
combination with a robot. To that end, a more comprehensive neuromechanical
assessment to distinguish all four clinical signs, might provide better
diagnosis. A robot device, combined with a scientific model, can presumably
identify and quantify the contribution of muscle weakness, abnormal reflex
activity, loss of independent joint control and changes in viscoelastic
properties to upper extremity impairment.

To develop a feasible assessment protocol to quantify the impaired upper
extremity function in terms of muscle weakness, spasticity, synergy and
viscoelastic properties around the elbow.
To evaluate the reliability (test-retest, measurement error) and construct
validity of the impaired upper extremity function parameters in chronic stroke
patients and adults with CP.

Two cross-sectional exploratory studies will be performed at Erasmus MC and
Rijndam Rehabilitation Center, The Netherlands.

This study is a non-invasive diagnostic study. During the study there will be
no direct benefits for the participants. However, results of the current
project can presumably facilitate treatment evaluation, treatment efficiency
and treatment policy in the long-term for these target populations. In this
study, a robot-arm device (SEP) developed by Hankamp (Enschede, the
Netherlands) will be used. The SEP imposes a force on the forearm of the
participants and measures relevant outcome parameters, which will be analyzed
using neuromuscular models. The device has several safety measures that are
explained in the IMDD file. Study participants will receive a SEP assessment
that takes up to 60 minutes and next to clinical measurements (Tardieu scale
and BMF/TASC).

Measurements can be experienced intensively for the affected arm because the
SEP-assessment will take up to an hour. In total 6 assessments will be
measured: 3 active measurements with the SEP-device, 1 passive measurement with
the SEP device, 1 active clinical assessment, and 1 passive clinical
assessment. During an assessment, 1 minute rest will be given between each
repetition and 5 minutes between assessments.
Patients will come to the hospital on different occasions:
For the first objective, the participants will come ones to the Erasmus MC.
For the second objective, the participants will come twice to the Erasmus MC (±
2 hours per visit).