Pediatric congenital tenosynovitis Pediatric congenital tenosynovitis occurs in infants and children between the ages of 4 and 5 years old, and is different from the stenosing tenosynovitis of adults. The main cause of congenital tenosynovitis is that the child’s nervous system is not well developed and the coordination of flexion and extension of the fingers is low; or because of habitual finger flexion and finger biting, or forceful grasping of toys and other reasons, the child’s fingers are often involuntarily in a state of flexion and tension, the thumb is bent for a long time resulting in inflammation and edema at the tendon sheath of the finger flexor tendon, and a hard nodule the size of a green bean appears under the skin at the finger near the joint. A painful nodule appears under the skin near the joint, and pressure is applied. The thumb (and occasionally other fingers) is passively flexed, and it is difficult to extend the finger, causing pain when the finger is passively extended, accompanied by a “trigger pull”-like popping sensation. If left untreated, some children may be unable to straighten their fingers due to prolonged flexion contracture of the finger flexor tendons, resulting in finger dysfunction. If congenital tenosynovitis in children is detected early by parents, there is usually no need to be overly nervous. Do not press and squeeze the hard knot of the affected finger, hot compress stimulation, because this will only aggravate the local edema, is not conducive to the dissipation of inflammation, there is no help for the straightening of the finger. The correct way to deal with the problem is: parents can gently hold the end of the affected finger, slowly pull the affected finger straight, keep the extended finger position for a few minutes, and then release the affected finger. If the affected finger regains the flexed position, repeat the pulling process again. This procedure can be repeated 5-10 times, 2-3 times per day. The vast majority of children will return to normal within a few days. In a very small number of cases where this method is ineffective, or where flexion of the affected finger has been prolonged and a contracture of the flexor tendon has occurred, surgical release is required at a children’s hospital. In children with congenital thumb tenosynovitis, surgical treatment is not usually necessary. Parents can give their children passive thumb stretching activities and do not knead the hard nodes on the palmar side of the thumb, and most children will be fine.