Soreness and weakness in the leg joints is mainly due to the following causes: 1. Trauma, such as common muscle strains or soft tissue contusions, joint injuries, which lead to soreness and weakness in the lower limbs. 2. May be due to some diseases, such as synovitis, rheumatoid arthritis, rheumatoid arthritis, gouty arthritis and other diseases, which lead to soreness and weakness in the leg joints. 3. 3, mostly due to strain in daily life, such as meniscal wear or osteoarthritis, resulting in weakness in the lower limbs. 4, due to a lack of calcium or potassium in the body, poor personal fitness, anemia and other conditions, triggering the emergence of weakness in the leg joints.