Osteogenesis imperfecta (OI) 

Osteogenesis imperfecta is not the same as osteoporosis. But both conditions cause weak bones. 

What is osteogenesis imperfecta? 

Osteogenesis imperfecta (OI) is a rare inherited genetic condition. It is sometimes known as brittle bone disease. OI is caused by faults or 'mutations' in the genes that control the production of collagen. Collagen is the main protein found in bone and is important for bone strength. 

People with osteogenesis imperfecta have bones that don't develop normally. The collagen in their bones isn't made correctly, or they don't make enough of it. This means their bones are much weaker than usual and are more likely to break (fracture) easily. 

There are around 5,000 people with osteogenesis imperfecta in the UK. It is usually diagnosed during childhood. Its severity varies a lot, even among people in the same family. It may be mild or lead to severe complications. People with mild OI don't have a lot of fractures and so tend to be a normal height. But people with severe OI tend to be shorter than other people because they have many fractures. In some very severe cases, babies can have fractures before birth. 

For more detailed information about osteogenesis imperfecta and its treatment, visit the Brittle Bone Society website

Is osteogenesis imperfecta the same as osteoporosis? 

No. They both cause weak bones, but in different ways. 

Osteogenesis imperfecta affects the collagen protein inside bone. Osteoporosis affects the mesh-like structure inside bone. The struts that make-up this structure become thin. The outer shell of the bone becomes thin too. 

I have been told I have osteoporosis, but could I have osteogenesis imperfecta instead? 

This is very unlikely, especially if you are over the age of 50. 

Osteogenesis imperfecta is usually discovered during childhood when bones break very easily. Osteoporosis usually develops in later life - especially in women who have been through the menopause. 

However, osteogenesis imperfecta is occasionally diagnosed in adults. This is not very common, but might happen if you have: 

• a history of breaking bones easily as a child or teenager, or a family history of early-onset osteoporosis 
• a condition called hypermobility, where your joints are very flexible - sometimes known as being 'double-jointed'
• a child who has been diagnosed with osteogenesis imperfecta. 

In such cases, it may be worth discussing the possibility of osteogenesis imperfecta with your GP or specialist. 

If you have a bone density scan, an OI expert will need to look at your scans. Both osteogenesis imperfecta and osteoporosis cause a low bone density result. Extra care will be needed to interpret your results. 

Is osteogenesis imperfecta a risk factor for osteoporosis? 

No. Having osteogenesis imperfecta does not increase your risk of developing osteoporosis. But it does mean your bones are likely to be weak. As you get older, age-related bone loss and the menopause can make your bones even weaker. This means it is usually helpful to remain under the care of an OI specialist, especially if you are breaking bones easily again. 

What can I do help my bones? 

Your OI specialist will be able to give you the best advice on how to look after your bones. Having enough calcium and vitamin D is important. A healthy, varied and balanced diet can provide good amounts of calcium. But your healthcare professional may suggest you take an added supplement to help you get enough calcium and vitamin D. 

Where possible take regular physical activity that involves your bones carrying the weight of your body such as walking. It's also important to maintain a good posture and avoid trips and falls, which could lead to broken bones. Avoid smoking and drinking more than the recommended limits of alcohol. 

Getting more information and support

Our specialist Helpline nurses can help with any questions or concerns about osteoporosis or general bone health. But you'll need to speak to a specialist in osteogenesis imperfecta if you have, or are worried about, osteogenesis imperfecta. 

You may also find the Brittle Bone Society or Strongbones Children's Charitable Trust helpful. They should be able to give you more detailed information about osteogenesis imperfecta. 

Content reviewed: August 2023