The primary manifestations of rheumatoid arthritis in the knee include swelling, pain, and functional impairment, accompanied by significant limitations in movement. As the condition progresses, it may lead to joint deformities, severely impacting the patient's quality of life. Systemic symptoms such as fever, fatigue, weight loss, and anemia may also occur. When knee swelling is pronounced, there can be a significant accumulation of fluid in the joint cavity, and a popliteal cyst may develop. Therefore, timely diagnosis and treatment are crucial. Local measures, such as joint aspiration and intra-articular corticosteroid injections, can be performed to alleviate symptoms, providing anti-inflammatory, analgesic, and anti-swelling effects.