There are several common reasons for painful pressure on the muscles under the thumb: first, local tendon sheath cysts that have grown to compress the nerves and cause painful pressure. In this case, the patient can improve the ultrasound examination to clarify the size and location of the tendon sheath cyst, and try to perform surgery to remove the tendon sheath cyst. During the operation, attention should be paid to the complete removal of the cyst wall to avoid recurrence of the cyst; second, the patient is accidentally hit by a foreign object, which can cause laceration of the muscles under the thumb, accompanied by the formation of a hematoma. At this time, the patient will have obvious pressure pain, and the patient can reduce tissue exudation by applying local ice. 24 hours later, using hot ointment pack for external application and blood circulation and stasis cream for external application, the hematoma tends to absorb on its own in patients with mild symptoms and pain relief. If the hematoma is too large to be absorbed, surgical incision and drainage can be performed to control the local pain and infection symptoms as soon as possible.