Biofeedback Training for Knee Joint Range of Motion in Patients with Ischemic Cerebral Stroke: a Pilot Study

BACKGROUND: After a stroke, patients often have impaired knee flexion of the paretic limb, which is one of the most common issues affecting walking ability. Biofeedback on joint kinematics is a relatively new technology that requires further research to understand its capabilities. AIM: The study aimed to evaluate the potential of using biofeedback to improve knee flexion range of motion in patients with hemiparesis during the early recovery period after ischemic cerebral stroke. METHODS: The main group of patients (n = 11; hemiparesis; early recovery period after ischemic cerebral stroke) completed a biofeedback training program for knee flexion range of motion, as well as a personalized rehabilitation program. The comparison group (n = 11) had the same selection criteria but received only standard rehabilitation. A biomechanical gait evaluation and clinical evaluation using various scales were performed before and after treatment. The control group included practically healthy volunteers (n = 34). RESULTS: A clinical evaluation using the scales showed significant improvement (p 0.05), as did two domains of the International Classification of Functioning, Disability, and Health. General functional patterns typical of hemiparetic gait were observed: decreased ability to support weight on the paretic limb, impaired reciprocity, and step-to-step asymmetry. In addition, a decrease in joint flexion range of motion was observed due to the paretic limb becoming relatively longer. Muscle activity decreased in nearly all muscle groups, particularly the calf muscles. This decrease reflected a reduction in ankle flexion range of motion and a condition known as drop foot. The absence of high-amplitude flexion was due to the weakness of the posterior thigh muscles. Analysis of step cycle phases in the main group revealed significant decreases (p 0.05) in the contralateral support and total double support phases. Reduced support on the healthy side led to a decreased load because both limbs provide more uniform support. This type of biofeedback training significantly increased (p 0.05) the swing range of motion of the paretic knee during weight transfer. This range of motion was the target of biofeedback training. The comparison group showed no significant change in the range of motion. CONCLUSION: Biofeedback training lasting 20 minutes for 10 days helps to reduce step asymmetry, increase endurance, and improve safety when walking. Biofeedback training is a promising noninvasive, non-drug treatment option for poststroke disorders. It has minimal contraindications and can be used to restore knee joint flexion range of motion and improve the support capacity of the paretic limb in patients during the early recovery period after ischemic stroke.