The causes of right leg pain include muscle strain, sciatica, lower limb vascular disease, etc., as follows: First, muscle strain: it may be a muscle strain or muscle strain of the right lower limb, mostly caused by too much sports. When sports are too strenuous, it is easy to cause strains in the thigh muscles, or excessive accumulation of lactic acid in the thigh muscles, which can cause pain and soreness in the legs. Second, sciatica: If the pain in the right leg radiates from the back of the buttock to the calf, it is generally considered to be sciatic pain, which may be due to a herniated lumbar disc compressing the nerve root, or it may be pear-shaped muscle syndrome. Third, lower limb vascular diseases: such as lower limb occlusive vasculitis, due to the reduction of blood supply to the lower limbs, it will cause the feeling of coldness and pain in the lower limbs. In addition, there may be venous thrombosis of the lower limbs, which may also cause swelling and pain in the right leg.