Objective:

1. to investigate reliability, validity and responsiveness of shearwave elastography (SWE) to assess muscle stiffness of overactive upper or lower limb muscles in different angle joint positions in patients with neurological condition
2. to investigate the relationship between muscle stiffness measured by SWE and by MyotonPro
3. to investigate the correlation between muscle stiffness measured by SWE and clinical outcomes

Methods: each patient will be assessed three times: two times at an interval of 15 minutes on the same day and one time at an interval of one week at the same time of the day. The following measurements will be made at each evaluation: SWE, MyotonPro, clinical evaluation. SWE and MytotonPro will be taken at different angle joint position.

Outcomes: muscle stiffness measured by SWE and MyotonPro at different angle joint positions, and clinical evaluation (passive range of motion, modified ashworth scale, tardieu scale, fuglmeyer) Hypothesis: SWE is a valid, reliable, and resposive method to assess muscle stiffness in neurological population with muscle overactivity. The results of SWE will be correlated with the results of MyotonPro and with clinical outcomes.

Inclusion Criteria:

• age > 18 years
• hemiparesia/-plegia following neurological condition (TBI, stroke,...)
• > 3 months after injury
• muscle overactivity in lower limb

Exclusion Criteria:

• other neurological or orthopaedic conditions involving the affected limb
• aphasia or major cognitive impairment limiting functional assessment
• botulinum toxin injection in the last 3 months
• previous treatment of muscle overactivity with surgical procedures.

In- or outpatients of the physical rehabilitation unit of the Cliniques universitaires Saint-Luc