Tendon sheath cysts are usually painful only when they are large or have recently been active. There are two ways to deal with this condition: first, reduce the activity of the joint as much as possible, or use simple braces for external fixation to reduce the friction of the tendon in the tendon sheath to avoid further increase in the size of the cyst, and at the same time, you can use topical Yunnan Baiyao aerosol to help to relieve the symptoms. Secondly, if the size of the cyst is increasing and the treatment described above is not effective, a simple surgery can be performed to remove the tendon sheath cyst, followed by some joint rehabilitation exercises to gradually restore the normal level. Although there is still a possibility of recurrence of the surgery after removal of the tendon sheath cyst, this possibility is relatively low and the surgical treatment is more effective.