What could a golf ball size hard knot be on the back of your infants head be?

A golf ball-sized hard knot on the back of an infant's head could be a number of things, some potentially serious. It is important to have the knot evaluated by a healthcare provider as soon as possible. Some potential causes of a golf ball-sized hard knot on the back of an infant's head include:

- Cephalohematoma: A cephalohematoma is a collection of blood that forms under the scalp of a newborn baby. It is usually caused by trauma during childbirth and is not typically serious. However, if the cephalohematoma is large or growing, it may need to be drained.

- Subgaleal hematoma: A subgaleal hematoma is a collection of blood that forms between the scalp and the skull of a newborn baby. It is also usually caused by trauma during childbirth and can be more serious than a cephalohematoma.

- Caput succedaneum: A caput succedaneum is a temporary swelling of the scalp of a newborn baby. It is caused by pressure on the scalp during childbirth and is not usually serious.

- Encephalocele: An encephalocele is a rare birth defect in which the skull does not close completely, allowing brain tissue to protrude through the opening. Encephaloceles can be serious and may require surgery.

- Dermoid cyst: A dermoid cyst is a rare type of birth defect in which a small sac filled with skin cells and other tissue forms under the skin. Dermoid cysts are usually benign, but they may need to be removed if they become infected or cause problems.

It is important to remember that only a healthcare provider can accurately diagnose the cause of a golf ball-sized hard knot on the back of an infant's head. If your child has a knot on their head, it is important to seek medical attention immediately.