1. Symptoms of congenital stenosing tenosynovitis The inability to straighten the thumb occurs in infancy, and others can break the thumb straight for him, but there is a relatively high resistance. There are times when there is a popping sound. There are also times when the thumb is in extension and cannot be bent, which is relatively uncommon. The appropriateness of this name is still controversial, because etiologically speaking, tendonitis is not necessarily present at birth and is not related to genetics. It is only now agreed that it is called so to distinguish it from tendonitis that occurs in adulthood. 2. What causes As with tenosynovitis in adults, thickening of the tendon can be found during surgery, creating a snag at the narrow tendon sheath, so the finger cannot move. It is estimated that this is caused by abnormal edema in this area during the development process. 3.Can it be cured? The cure rate is 100%. There is no need to worry. 4.How can I treat it? Children have great plasticity. There is no need to be busy with surgical treatment, conservative treatment can achieve a high success rate. Help your child to move the thumb frequently, straighten it passively and correct the bent condition. It is a good idea to make a splint-like thing to hold the thumb in a straightened position during the day. The easiest way to do this is to use a small wooden scoop of ice cream with some band-aids to hold it in place. Or use tape to hold the thumb in a straightened position. Each parent can come up with their own suitable solution. Especially at night, fix it on. During the day the child plays and it may come loose, but of course it does not have to be fixed 24 hours a day, all the time. 5.When do I need surgery? Generally, with the above conservative treatment, the problem can be solved within 2-3 years old. If you still can’t straighten it after 3 years old, you can consider surgery. General anesthesia is required. There is no evidence that general anesthesia affects intelligence. The surgery is simple, and loosening the tendon sheath is sufficient. There is a potential risk of damage to tendons and nerves.