Neuromuscular Control and Motor Unit Behavior in Patients With Knee Osteoarthritis

Inclusion Criteria: \- 1. age 55 to 75 years. 2\. Diagnosed with moderate knee traumatic arthritis (Kellgren-Lawrence classification II or III)(experimental group). The control group must not have a diagnosis of osteoarthritis of the knee and must have normal knee joint function. 3\. Physical Health Status: Able to perform basic movements requiring isometric knee contraction tests and electromyography recording. 4\. Able to wear knee orthotics. Exclusion Criteria: * 1\. Knee or lower extremity injury: Recent (within the past 6 months) history of severe injury, fracture, or surgery to the knee or lower extremity. 2\. Other joint disorders: Coexisting joint disorders (such as rheumatoid arthritis or gouty arthritis). 3\. Neuromuscular disorders: Presence of neuromuscular dysfunction, such as stroke, Parkinson's disease, or peripheral neuropathy. 4\. Uncontrolled cardiovascular disease, hypertension, diabetes, or other medical conditions. Taking medications that affect neuromuscular function. 5\. Allergy or intolerance: Allergy to laboratory equipment (such as electromyography electrode gel) or knee brace materials.