The Assessment of Knee Joints Function in People After Stroke

Stroke patients were examined twice at the beginning of rehabilitation and after approximately 15 days of exercise. The control group (healthy participants) was assessed once. Wireless motion sensors connected to a mobile application were used to assess the kinematics of the knee joints. They were used to assess the range of motion in the knee joints (passive, active, active at maximum speed), proprioception (joint position sense tests), step-up test, step-down test, getting up and sitting on a chair, step and squat. Functional tests such as The Five Times Sit-to-Stand Test, Timed Up&Go, The Step Test, the 5m walking test, and the 30-s Chair Stand Test were carried out. The strength of the knee extensors and flexors was also assessed using the Leg Force Feedback device. Balance was assessed on a posturography platform by performing tests such as standing with eyes open and closed on a stable surface and standing with eyes open and closed on an unstable surface. The symmetry of lower limb loads in a standing position was also assessed.

Inclusion criteria

to the stroke group were as follows :

• the time from stroke: less than a year,
• age: between 35 and 65 years old,
• ability to stand independently for at least 5 minutes without an assistive device,
• ability to walk 5 m independently,
• ability to communicate and understand the tasks required in the study,
• a modified Ashworth scale spasticity score of 1+ or less in the affected knee (0: no resistance, 5: affected parts stiff in flexion or extension),
• muscle strength on the Manual Muscle Test of 3/4 or more in the affected knee,
• Barthel Index score 80 or more.

Exclusion criteria

from the post-stroke group were as follows:

• age below 35 or over 65,
• sensorimotor aphasia,
• cognitive disorders that make it impossible to understand and obey commands,
• lack of active movement in the knee joint,
• Manual Muscle Test strength of the quadriceps muscles below 3,
• no ability to walk 5 meters,
• lack of informed consent to participate in the study,
• other neurological diseases (such as MS, Parkinson's disease, neuropathies),
• fractures in the lower limbs, which could affect the structure and function of the knee joint,
• previous operations on the lower limbs (including ACL reconstruction, knee arthroplasty or hip, osteotomy of the knee joint).
• vision disorders,
• unilateral spatial neglect syndrome.

The control group consisted of healthy volunteers with no prior history of trauma or neurological disease affecting the structure and function of the lower limb.