Osteogenesis imperfecta (brittle bone disease): symptoms and treatment

Great Ormond Street Hospital says the main feature is fractures usually caused by minimal impact, and that symptoms can range from very mild to severe. The Brittle Bone Society says bones may break at any time, even without trauma, and some people with OI hardly have any symptoms while others have a physical disability that needs walking aids or wheelchairs.

• Fractures with minimal force, which varies from child to child.

• Bones with an altered shape, such as shortened or bowed bones, and scoliosis (curvature of the spine).

• The whites of the eyes appearing blue or grey (blue sclerae).

• Hypermobile or very flexible joints, ligaments that stretch easily and joint or bone pain.

• Problems with the formation of teeth (dentinogenesis imperfecta), described as brittle teeth.

• Tiring more easily than other children, and shorter stature.

• Hearing problems, which GOSH says usually affect people after puberty.

OI is a disorder of collagen. Collagen is a protein found throughout the body, especially in bones, ligaments, tendons and skin. In OI there is either not enough collagen or it is of poor quality, so it cannot support the mineral structure of the bone. This makes the bones weak and fragile.

The Brittle Bone Society says a classification system describes the different types, and severity can be described as mild, moderate or severe. Because collagen is found in other tissues too, there can be problems beyond the bones, such as loose joints, hearing loss and fragile teeth.

A genetic condition such as OI can be passed from parents to children. The Brittle Bone Society says around 25% of children with OI are born into a family with no family history, when the child has a new (spontaneous) dominant mutation. The adult health factsheet from the same charity says that with most forms of OI there is a 50% chance that a baby will inherit the condition from an affected parent.

If you are thinking about having children, the factsheet suggests discussing it with your specialist and seeking advice from a geneticist, and that you may also need to see an obstetrician to discuss possible difficulties during pregnancy and delivery. It says women should usually avoid getting pregnant while taking bisphosphonates, and you can talk to your specialist about contraception.

Great Ormond Street Hospital says no single test can identify OI in all cases. In most cases it is diagnosed clinically: the doctor performs a physical examination and takes a full medical history. X-rays are usually suggested to check for fractures and bone changes.

Bone density (DEXA) scans can be carried out on children weighing more than 10kg, but there is not enough data to give accurate results under the age of five. Genetic testing is possible but not undertaken routinely, and OI remains a clinical diagnosis.

Great Ormond Street Hospital says the majority of people with mild or moderate OI are treated with physiotherapy and management of symptoms as they occur. The main medicines are bisphosphonates, such as pamidronate and zoledronic acid, which prevent loss of bone mass. Your child may not need treatment soon after diagnosis but could benefit from it months or years later, and some children never need bisphosphonates. Vitamin D supplements are recommended for all patients, as vitamin D helps the body absorb calcium and make bone.

The Brittle Bone Society's bisphosphonate factsheet says bisphosphonates may increase bone density, reduce bone pain and in some studies reduce fractures. They are not a cure for the underlying collagen defect and are best used in centres able to provide multidisciplinary care, including orthopaedic surgeons, physiotherapy and occupational therapy.

The Brittle Bone Society says intravenous bisphosphonates often cause a flu-like reaction the first time, with a temperature and aches that usually settles within two to three days and does not normally recur. Some oral bisphosphonates can cause stomach discomfort or irritation of the oesophagus if not taken as recommended.

It says some centres pause treatment for a few weeks before planned surgery that involves cutting a bone, because healing after such an operation can be slower, and that there is no evidence that bisphosphonates slow healing of a fracture or interfere with growth. It recommends regular dental checks and good oral hygiene, and that dentists know if you are taking one before any planned procedure. It also says the effects reported seem generally positive for children and less so for adults.

Great Ormond Street Hospital says children with OI will continue to need regular check-ups from a specialist OI service throughout childhood and adolescence before moving to an adult service at around 16 to 18 years of age, with discussion starting at around age 12. It says that with some adaptations, children and young people can have a near-normal lifestyle, attending school and college and starting work.

The Brittle Bone Society says NHS England commissions specialist services for children with complex, severe or atypical childhood OI, which provide multidisciplinary care and advice to the local hospital team. Ask your GP or paediatrician about referral if OI is suspected.

The Brittle Bone Society's adult factsheet says most adults experience a decrease in the rate of fractures after puberty, but that tendon, muscle and joint problems may worsen with time and hearing loss may become significant. It says approximately 50% of adults with OI will experience some degree of hearing loss in their lifetime, and recommends hearing and vision checks every two to three years.

It also lists breathing problems as the main concern for many adults, particularly with significant spinal curvature, so chest infections should be treated quickly; heart valve problems in a small number of people; and kidney stones in about 20% of people. Tips for staying healthy include maintaining a healthy weight, a balanced diet with appropriate calcium and vitamin D, not smoking, using alcohol in moderation, a safe low-impact exercise programme and regular bone density scans.

On the NHS, children with suspected or confirmed OI are usually referred through a paediatrician to a specialist metabolic bone or OI service, with local teams providing fracture care. Adults are seen by endocrinologists or rheumatologists, often in a metabolic bone clinic, supported by orthopaedics, physiotherapy and occupational therapy.

Private paediatric and endocrine services can assess bone health and arrange scans, but OI is a lifelong condition best managed by teams with experience of it. Ask how any private care would link to NHS specialist services so that bisphosphonate treatment, scans and fracture care stay coordinated.