A. An 11 year old boy who is 4'5" tall is at the 10th percentile for his height, and while short, if that is where he has always been on his growth chart, he is likely growing normally.
Genetics plays a very big role in how tall a child will be. Based on this height predictor, a boy who has a mother who is 5' and a father who is 5'8" tall has the genetic potential to be 5'6" tall. That is also at the 10th percentile for height for an adult and would currently place him right on track to meet his genetic potential for his height.
So he likely has familial short stature, a common cause of short stature in which a child's parents and other family members are also short. These children usually grow at a normal rate, although they are short, and they follow a growth curve that may be below, but runs parallel to the normal growth curves.
When evaluating children who are short, more important than where they are on a growth chart is how they have been growing. To look at this pattern of growth, or a child's height velocity, you usually have to look at several years of growth. Children who are growing normally should follow their growth curve fairly closely, so even if they are at the 5th or 3rd percentile, if that is where they have always been, then they are probably growing normally. If your child is crossing percentiles or lines on the growth curve, then there may be a medical problem causing him to be short. Keep in mind that children may normally cross percentiles in the first few years of life and this is actually a common finding in children with familial short stature or a consititutional growth delay.
Other red flags that may indicate a growth problem include having a chronic medical condition or other symptoms, such as vomiting, diarrhea, fever, weight loss, poor appetite, poor nutrition, headaches, delayed puberty, having disproportionate short stature, which can be a sign of a chromosomal disorder, or being short and overweight, which can indicate an endocrine or hormonal problem.
The most important part of an evaluation of children with short stature is reviewing their growth records. If you have had more than one Pediatrician, then it is a good idea to get all of your children's old records. If they are short, but growing normally, then no further testing may be required. Your doctor may decide to just observe your children's growth over the next 3-6 months to make sure that they continues to grow normally.