Importance of the assessment of knee joint function after a stroke

Purpose: This study aimed to assess knee joint function in post-stroke patients using wireless motion sensors and functional tests. This type of evaluation may be important for improving gait quality. Methods: The study included 25 post-stroke patients (age 53.5 ± 8.4 years) and 25 healthy controls (age 51.1 ± 7.7 years). Knee function was assessed using passive range of motion (PROM), active range of motion (AROM) at any speed, maximum speed AROM (FROM), and joint position sense (JPS). Orthyo^® motion sensors and a mobile app were used for measurements. The following functional tests have been used: Five Times Sit-to-Stand Test (FTSST) and Timed Up and Go Test (TUG). Results: Before rehabilitation, the average values of PROM ( p = 0.006), AROM ( p = 0.005), FROM average ( p < 0.001) and maximal velocity ( p < 0.001), JPS 30° ( p = 0.002), JPS 60° ( p = 0.002) and JPS 80° ( p < 0.001) were significantly worse in the paretic limb than in healthy people. The applied rehabilitation contributed to improving the PROM and AROM and the average and maximum speed of rapid movement in the knee joint. Proprioception (JPS) also improved. Only the average ( p < 0.001) and maximum speed ( p < 0.001) in the FROM test in the knee joint of the paretic limb after rehabilitation significantly differed from the values in healthy people. The patients' performance (functional tests) improved after rehabilitation (TUG ( p < 0.001) and FTSST ( p < 0.001)), but it did not reach the level of healthy people. Conclusions: The function of the knee joint in the paretic limb is significantly impaired and requires inclusion in the therapy plan in the early period after stroke.