Nephrotic syndrome is mainly manifested by large amount of proteinuria, hypoalbuminemia, edema, hyperlipidemia and so on, which usually does not cause arm pain. If arm pain occurs in combination, it is generally considered to be caused by thrombus, local inflammation and other conditions. 1. Thrombus: patients with nephrotic syndrome have increased blood viscosity, and the blood is hypercoagulable, which can cause thrombus. If the thrombus occurs in the arteries of upper limbs, the upper limbs will be ischemic and hypoxic, and arm pain may occur. 2. Local inflammation: patients with nephrotic syndrome have a large amount of protein loss, and their body resistance is relatively poor, so they are prone to inflammation. If patients have upper limb muscle inflammation, arm pain may also occur. If patients with nephrotic syndrome suffer from frequent arm pain, it is recommended to consult a doctor for examination in a timely manner, clarify the cause of the disease under the guidance of a professional physician, and treat the disease in a timely manner.