Baby just after birth, always like to hold the little hand into a bulging fist, in fact, this is due to the baby’s cerebral cortex development is still immature, hand muscle activity regulation is poor, resulting in the contraction of the muscles of the flexor finger dominant, and the relative lack of strength of the muscles of the fingers, the baby always clenched two small fists, the baby’s hand most of the time is a clenched fist state, the thumb is other The four fingers are wrapped in it, sometimes sticking out. The younger the baby is, the more obvious this phenomenon is, which is called the “grip reflex” and is a normal physiological phenomenon. As the baby grows, when the baby reaches 3 to 4 months, with the gradual development and maturity of the nervous system, the strength of the flexor muscles will gradually weaken, the strength of the extensor muscles will gradually increase, and the two will gradually reach a relatively balanced state, by then, the baby’s small hands will also show a relaxed and free state. But due to individual differences in babies, some babies will appear slightly open fingers, or all open phenomenon, this is normal, this is the natural growth process of babies. But parents are not recommended to break the baby’s fingers in order to send friends, or attention, which will lead to poor bone and muscle development, and do not force the baby to make other, not the baby’s age can make the behavior! For the newly promoted parents of the parents, in the parenting road is “thorns all over”, “bumpy”, a single we are used to the baby holding a small fist phenomenon, are a big learning. The daily parents will be confused baby normal fist and thumb in the buckle, the following we will talk about the difference between the two. The thumb inside the buckle: is the baby’s hand open palm, the thumb position for across the palm clenched in the hand, this is the thumb inside the buckle, also called the skin thumb sign, is not normal phenomenon. Normal fist clenching: not across the center is the normal fist clenching reflex, fist clenching reflex is a normal physiological phenomenon. Identification method 1, 3 months old baby: gently tap the back of the baby’s hand, the baby’s hand will open, observe the position of the thumb; clenching fist more than opening time during the day. 2, 3-4 months: about half of the time open, half of the time clenched fist. 3.After 4 months of age: the hand is basically fully open, and you can observe the position of the thumb when the baby grasps something. If after more than 3 months, the baby’s hand still continues to make a fist, can not open or thumb inward, then parents should be alert to the following possible diseases. 1. Neurological damage. Especially premature babies, babies with hypoxic asphyxia, babies with meningitis 2, high muscle tone. Excessive strength (tension or spasm) of the thumb retractor, thumb-to-palmar and thumb short flexor muscles 3, low muscle tone. Short thumb extensor, short thumb extensor, long thumb extensor, and long thumb extensor are not strong enough If the baby is frightened, crying, or tense, it may also cause a short period of internal thumb clenching, so make sure the baby is relaxed during the physical examination. If parents suspect that their baby has an inward thumb, it is recommended that they take their baby to a regular medical institution for a thorough examination and early intervention under the guidance of a professional physician or rehabilitator!