Effects of Visual Feedback-Based Neck Exercise Training on Neck Position Sense and Balance in Patients with Chronic Stroke

INTERVENTION: Behavioral : All participants received a total of 90 min of intervention per day, five days per week for eight weeks. Both groups received 60 min per day of general neurodevelopmental treatment consisting of trunk control, weight‐shifting, sit‐to‐stand practice, standing balance, and gait training. An additional 30‐min cervical intervention consisted of 10 min of deep cervical flexor exercise and 20 min of group‐specific cervical sensorimotor training. Deep cervical flexor exercise was performed in the supine position using a pressure biofeedback unit placed beneath the cervical lordosis and inflated to a baseline pressure of 20 mmHg. Participants performed a gentle nodding movement without lifting the head. The target pressure was progressively increased through five levels of 22, 24, 26, 28, and 30 mmHg. Cervical sensorimotor training consisted of three 5‐min training sets, each followed by a 1‐min seated rest period. In the experimental group, participants wore a head‐mounted laser device and traced a 100‐cm‐long zigzag target positioned horizontally and vertically on a wall 1 m in front of them. The laser remained on during training, allowing participants to observe its position and trajectory and make immediate movement corrections using concurrent real‐time visual feedback. In the control group, participants used a black reference point positioned on a wall 1 m in front of them and attempted to return to the memorized neutral head position after cervical flexion, extension, left rotation, or right rotation. The laser was turned off during movement. After participants indicated that they had reached the neutral position, the laser was turned on for approximately 3 s to display the repositioning error, and the therapist provided delayed knowledge of results. Intervention duration, training frequency, number of sets, rest periods, and therapist supervision time were matched between the two groups. CONDITION: Diseases of the circulatory system PRIMARY OUTCOME: Change in Cervical Joint Position Error (JPE) (cm) SECONDARY OUTCOME: Change in Berg Balance Scale (BBS) Score (points) Change in Craniocervical Flexion Test (CCFT) Score (mmHg) Change in Sternocleidomastoid Muscle Stiffness (N/m) Change in Timed Up and Go (TUG) Test Time (seconds) Change in Upper Trapezius Muscle Stiffness (N/m) INCLUSION CRITERIA: Patients with hemiplegia diagnosed with either hemorrhagic or ischemic stroke based on computed tomography (CT) or magnetic resonance imaging (MRI) Patients with chronic stroke at least 6 months after onset A score of 24 or higher on the Mini‐Mental State Examination–Korean version (MMSE‐K) The ability to walk independently for at least 10 m, with or without an assistive device Spasticity of the paretic neck and shoulder muscles of grade 2 or lower on the Modified Ashworth Scale (MAS) Corrected visual acuity of 0.3 or higher, sufficient to perform visual training