Juvenile Osteoporosis
What Is Juvenile Osteoporosis?
Osteoporosis means “porous bones” or weaker bones. When a person has osteoporosis, their bones are less dense or strong when compared to a person without osteoporosis. In adults, this diagnosis can be made based on the results of a test called a dual energy x-ray absorptiometry (DXA) scan. In children, the term osteoporosis is used when the density of the bones is significantly below normal (noted on the DXA scan) AND they have a fracture history. A more concerning fracture history is when a child breaks a number of long bones, such as their forearm or leg instead of a couple of small bone fractures such as fingers and toes. The diagnosis of osteoporosis can also be used in children if a child has had a vertebral compression fracture (fracture in the spine) even if they did not have a DXA scan done. Since children build 90 percent of their bones in the first 20 years of life, it is very important to identify osteoporosis early.
What Causes Juvenile Osteoporosis?
Osteoporosis in children can be from a number of different causes. The main type of osteoporosis that children have is called secondary osteoporosis. Within secondary osteoporosis, a big factor is whether children are being treated with medications called corticosteroids, or steroids. Osteoporosis in children can also be a primary problem without a known cause.
- Secondary osteoporosis: A child has weak bones that are being caused by another health problem.
- Health problems that cause other issues in the body such as inflammation or trouble with absorption tend to place a child at risk for osteoporosis. Examples of this are juvenile rheumatoid arthritis, lupus, diabetes, kidney or liver disease, anorexia nervosa, celiac disease, crohn’s disease, or ulcerative colitis.
- The osteoporosis can also be secondary to the strength of a child and their ability to walk or not. For example, children with cerebral palsy are at higher risk of fracture and low bone density. This is similar in neuromuscular diseases such as spinal muscular atrophy, Duchenne muscular dystrophy, congenital muscular dystrophy, myotonic dystrophy and some peripheral neuropathies. In these cases, if a child is able to walk on their own, they are at lower risk of osteoporosis, and if a child cannot stand or walk on their own he or she is at higher risk for fracture and osteoporosis.
- Osteoporosis can also happen secondary to hormone imbalances. Hyperthyroidism causes the thyroid gland to be too active, which increases bone loss. The loss of menstruation or periods due to poor nutrition, overexercising or other health conditions can lower estrogen in the body, leading to lower bone density.
- Osteoporosis can be related to underlying skeletal dysplasias or genetic problems with the bones. An example of this is osteogenesis imperfecta, where a child either does not make as much bone, or makes poor quality bone, leading to low bone density, fractures and often osteoporosis.
- Medications are a big cause of decreases in bone density and possible development of secondary osteoporosis. Some seizure medications can affect the way the body absorbs vitamin D (and possibly other nutrients). Some chemotherapy or cancer treatments as well as transplant anti-rejection medications can lower the bone density.
- Corticosteroids, or steroid, medications are one of the biggest causes of lowering the bone density in children and adults. These medications are used frequently for problems with inflammation like arthritis or asthma. Corticosteroids can slow normal bone cell growth and can cause faster loss of minerals like calcium from the bones. If someone is on short courses of steroid medication more than 3 times per year or takes daily steroid medications for 3 months or longer, they are at risk for bone loss.
- Idiopathic juvenile osteoporosis: When a child has weak bones and is fracturing without a known cause.
- Sometimes, this is called a “diagnosis of exclusion,” meaning that the other causes listed above are investigated but no cause is found.
- This can happen at any age in childhood, but is most common in school-aged children.
What Are Signs & Symptoms of Juvenile Osteoporosis?
- Bone pain, most commonly in the back and lower extremities
- Multiple fractures of the long bones or of the spine, especially from low trauma
- Physical deformities such as rounding of the back (kyphosis) and loss of height
How Is Juvenile Osteoporosis Diagnosed?
A detailed history and physical is important in diagnosing osteoporosis, since there can be primary and many secondary causes of it. Bone density problems are diagnosed with a radiology test called dual-energy x-ray absorptiometry (DXA) scan. This scan does use radiation similar to a traditional x-ray, but at much lower amounts, making it a very safe test. This test is most commonly done in adults, usually in women above 50 years of age since they are at greatest risk for low bone density. It is done in other age groups as well if there are risk factors. The areas to measure and the comparisons used to understand the test results are different in adults and children. Because of this, it is best that your child have this test performed at a facility that frequently evaluates children. Additionally, the test is sensitive, so it is better to have follow up tests done on the same machine over time. In adults, T-scores are used. These compare the person being evaluated to a general group of persons in their 20’s. In children, Z-scores are used, which compare children to age and gender matched peers. A normal Z-score in a child is between –1.0 and +1.0. Low bone density is diagnosed with a Z-score </= -2.0 without a history of fracture. Osteoporosis is diagnosed if the Z-score is </= -2.0 with a significant fracture history. Your child’s provider may make a diagnosis of osteoporosis with a Z-score < –1.0 depending on other clinical factors.
How Is Juvenile Osteoporosis Treated?
If your child has been diagnosed with osteoporosis, the first thing to figure out is the cause. If the cause is something treatable, such as celiac disease or hyperthyroidism, then treating that health problem helps treat the osteoporosis. If it is from a cause that cannot be fully treated, then it is important to focus on improved nutrition and physical activity. You will need to make sure your child is getting enough calcium and vitamin D in their diet. Additionally, physical activity can make a positive difference in bone density, especially during the years around puberty. Physical activity should include weight bearing activities that can include walking, running, soccer, baseball, and tennis. It should also include resistance exercises to help with muscle mass. These activities may include biking, rollerblading, swimming, and strength training.
If your child has idiopathic juvenile osteoporosis, it is possible that they may not need more than the above recommendations. This disorder can sometimes go away on its own as children go through puberty. If the osteoporosis worsens or does not resolve on its own, osteoporosis medications called bisphosphonates may be recommended. These medications are approved for and commonly used in adults with osteoporosis, but have shown some success in children as well.
What Are the Long-Term Effects of Juvenile Osteoporosis?
Osteoporosis can cause continued fractures and bone pain and possible bone deformity if left untreated.
Additional Resources
For more information, please refer to the following websites: