What are Adult Rare Bone Diseases
Adult rare bone diseases (ARBDs) are a group of conditions that disrupt bone health. These disorders can make bones more likely to break, become misshapen, grow too much or become unusually heavy.
There are many types of ARBDs, including Osteogenesis Imperfecta, X-Linked Hypophosphatemia and Fibrous Dysplasia. Each condition affects the bones differently and needs varying tests and treatments.
Osteogenesis Imperfecta (OI)
This is a condition that affects connective tissue, which supports the body. When it doesn’t work properly, bones become fragile and break easily.
It is caused by a problem with the gene that produces Type 1 Collagen, an important protein that gives bones their strength. There are different types of OI:
- Type 1 is the most common and mildest, with fewer fractures
- Type 2 is very severe and often life-limiting
- Type 3 is severe in those who survive infancy, with frequent fractures and bone deformities.
Diagnosis can occur in adulthood and is based on patient history, supported by blood tests, imaging (DEXA), and genetic testing.
There is no cure, and treatment focuses on managing symptoms, including bisphosphonates, calcium and vitamin D, as well as monitoring and physiotherapy.
X-Linked Hypophosphatemia (XLH)
This condition affects how the body handles phosphate, a mineral needed for strong bones. A mutation causes the body to lose too much phosphate through the kidneys, which leads to weak bones, causing symptoms including:
- bowed legs
- short height
- bone pain
- frequent fractures.
Diagnosis is based on blood and urine tests, scans and genetic testing. There is no cure, but treatment includes phosphate and vitamin D supplements, specific medications, and supportive care such as physiotherapy.
Fibrous Dysplasia (FD)
This condition causes normal bone to be replaced with softer, scar-like tissue, making bones weaker and more likely to bend or break.
FD can affect a single bone or multiple bones. Symptoms may include bone pain, fractures and sometimes early puberty.
Diagnosis is made using imaging such as CT scans, bone scans, and X-rays. There is no cure, but treatment focuses on managing symptoms, including pain relief, and regular monitoring.
What is the ARBDs Collaborative Network
Rare Disease Collaborative Networks (RDCNs) are NHS initiatives that aim to improve the diagnosis and treatment of patients with rare conditions.
The ARBD Collaborative Network focuses on improving care for adults with rare bone disorders, of which there are over 450 types. It helps bring together specialists across the UK to improve diagnosis, treatment and research.
Manchester is one of the leading trusts within the ARBD network and offers RDCNs regularly alongside 24 other providers. The ARBD network supports collaboration between specialists, improves patient pathways, and promotes research and education in rare bone diseases.
For further support and information, patients can access resources through organisations such as the Rare Disease UK Network and the Brittle Bone Society, which provide information, support groups, and guidance for those living with rare bone conditions.
For more information or to get involved, contact the NHS England Rare Disease Collaborative Networks team at england.rdcns@nhs.net.
Links
Credits:
Zainab Qaisar – University of Manchester medical student