Osteitis Fibrosa Cystica: Symptoms, Causes, and Treatment Guide
Updated: 2 days ago
Medically reviewed by Dr. Baraa Alnahhal, MD · Last reviewed: October 2026
Osteitis fibrosa cystica (OFC) is a rare bone disorder caused by untreated hyperparathyroidism, in which too much parathyroid hormone (PTH) weakens bones, causes deformities, and creates cyst-like holes. It was once common, but routine blood tests have made it rare: less than 5% of people with hyperparathyroidism in the United States develop it. Treatment usually means removing the overactive parathyroid gland or using medicine to control hormone levels, and bones can often rebuild afterward [1].
Quick Answer: What is osteitis fibrosa cystica?
Osteitis fibrosa cystica is a bone condition caused by long-term untreated hyperparathyroidism, which pulls calcium from bones and leaves them fragile and prone to fractures. Symptoms include bone pain, fatigue, weakness and kidney problems from high calcium. Blood tests and imaging confirm it. Standard treatment is a parathyroidectomy, after which bones can often remineralize and strengthen. [1]
What the research says
Fixing the parathyroid problem raises bone density. A meta-analysis of four randomized trials in mild, asymptomatic primary hyperparathyroidism (not OFC itself) found bone density was 3.55% higher in the lumbar spine and 3.44% higher in the total hip after parathyroidectomy than with active surveillance, with no clear difference in fracture risk (Anagnostis et al., J Endocrinol Invest, 2021).
Brown tumors tend to reverse after surgery. A systematic review of 52 articles covering 392 brown tumor lesions found that their uptake on nuclear imaging appeared reversible after parathyroidectomy, and that on several scan types they can mimic metastatic cancer (Jacquet-Francillon and Prevot, Ann Nucl Med, 2023).
What Is Osteitis Fibrosa Cystica?
Osteitis fibrosa cystica (OFC) is a complex bone disorder that arises as a rare complication of hyperparathyroidism. It occurs when the parathyroid glands become overactive and produce too much parathyroid hormone (PTH). PTH is essential for keeping bones strong, but too much of it makes the body break down bone tissue faster than it can be replaced [1].
The name points to the main features: bone changes with fibrous tissue and cyst-like holes. The result is weakened bones, structural deformities, and cavities within the skeleton. The condition was once known as von Recklinghausen’s disease of bone. Some clinicians call the bone lesions "brown tumors," but these are not cancer. They are areas of bone loss filled with fibrous tissue [1].
Term | Description |
Medical name | Osteitis fibrosa cystica (OFC) |
Historical name | Von Recklinghausen’s disease of bone |
Clinical feature | Brown tumor of bone (noncancerous lesions) |
Primary trigger | Long-term excess of parathyroid hormone (PTH) |
A long bone in cross-section: cyst-like lesions and fibrous tissue replace healthy bone while the outer cortex thins.
What are the symptoms and complications of osteitis fibrosa cystica?
Symptoms come mainly from weakened bone and from the effects of high calcium in the blood. The condition develops slowly over years of untreated hyperparathyroidism, so early signs can be subtle and easy to overlook [1].
Primary and Early Symptoms
Bone pain and tenderness: persistent aching, especially in the limbs or spine [1].
Frequent fractures: a higher chance of breaks in the arms, legs, or vertebrae [1].
General weakness: fatigue and muscle weakness [1].
Digestive issues: nausea, vomiting, and long-lasting constipation [1].
Urinary changes: urinating more often than usual (polyuria) [1].
Potential Complications
Left untreated, the hormone imbalance can harm more than the bones. High calcium (hypercalcemia) often leads to painful kidney stones and can eventually cause kidney failure. Some people also have abdominal pain, low energy, and depression [1].
What causes osteitis fibrosa cystica?
The only cause of osteitis fibrosa cystica is untreated hyperparathyroidism. This hormone disorder comes in two main types, depending on where the imbalance starts [1].
Type of hyperparathyroidism | Underlying cause |
Primary | A problem in the parathyroid glands themselves, such as a noncancerous or cancerous growth. |
Secondary | Another condition, such as vitamin D deficiency, lowers calcium and forces the glands to overwork. |
In both cases, the extra PTH makes the body pull calcium out of the bones and release it into the bloodstream. Over time, this leaves the bones hollow, fragile, and prone to the cyst-like changes of OFC [1].
How excess parathyroid hormone pulls calcium from bone and leads to bone loss, kidney stones, and fractures.
How is osteitis fibrosa cystica diagnosed?
A healthcare provider starts by reviewing your medical history and examining you for bone pain or visible deformities. Because OFC affects the whole body, testing looks at both hormone levels and bone health [1].
Blood tests: measure parathyroid hormone, calcium, and other minerals [1].
Imaging: X-rays and CT (computed tomography) scans show bone thinning, tiny fractures, and cyst-like lesions [1].
History review: your provider looks at long-term symptoms to see whether you may have had undiagnosed hyperparathyroidism [1].
How is osteitis fibrosa cystica managed and treated?
Treatment aims to bring PTH back to normal so bones can heal. The choice depends mostly on what is causing the hyperparathyroidism [1].
Surgical Intervention
The standard and most effective treatment for primary hyperparathyroidism is a parathyroidectomy, surgery to remove the overactive or abnormal parathyroid gland. Once the source of the extra PTH is gone, the body can start to reverse bone thinning and rebuild lost bone. Most people have four parathyroid glands, and the remaining glands can usually make enough hormone for normal function [1].
Medical Management
For people who cannot have surgery, or who have secondary hyperparathyroidism, other treatments include [1]:
Calcimimetics: medicines that mimic calcium in the blood, "tricking" the parathyroid glands into making less PTH.
Bisphosphonates: drugs commonly used for osteoporosis that slow bone loss.
Supplements: vitamin D and calcium may be prescribed to correct deficiencies in secondary hyperparathyroidism.
The path from diagnosis to recovery: blood tests and imaging, finding the cause, surgery or medication, then bone rebuilding and monitoring.
How can osteitis fibrosa cystica be prevented, and what is the long-term outlook?
The best way to prevent OFC is to find and manage hyperparathyroidism early. Routine blood tests can show high calcium before it does serious damage to the skeleton. Keeping vitamin D and calcium at healthy levels through diet, sunlight, and supplements, when advised by your provider, also helps [1].
With proper medical care the outlook is generally excellent. Treatment can stop bone thinning and let the skeleton remineralize, which improves quality of life and lowers the risk of future fractures [1].
What is the bottom line on osteitis fibrosa cystica?
Osteitis fibrosa cystica is rare today, but it is a clear reminder of what long-term untreated hyperparathyroidism can do to bone. If you have persistent bone pain, unusual fatigue, or a history of kidney stones, talk to your healthcare provider for a full evaluation. Finding and treating hyperparathyroidism early can prevent OFC and protect your long-term bone health.
Frequently Asked Questions
Is osteitis fibrosa cystica the same as osteoporosis?
No. Both conditions weaken bone, but OFC is caused by excess parathyroid hormone and involves cyst-like holes and fibrous tissue, while osteoporosis is a general thinning of bone density often linked to aging or estrogen loss.
Can the bone damage from OFC be reversed?
Often, yes. After successful treatment, such as a parathyroidectomy, bones can remineralize and regenerate, reversing much of the damage.
Why is it called a "brown tumor" of bone?
The lesions look brown because of iron-containing blood breakdown products from bleeding inside the bone. Despite the name, they are not cancerous tumors.
How common is osteitis fibrosa cystica today?
Osteitis fibrosa cystica is very rare in developed countries because routine blood tests catch hyperparathyroidism early. Less than 5% of people with hyperparathyroidism in the U.S. develop OFC.
What happens if I do not treat hyperparathyroidism?
Untreated hyperparathyroidism can lead to severe bone pain, frequent fractures, kidney stones, and possibly kidney failure.
Does surgery for OFC involve all the parathyroid glands?
Usually only the abnormal or overactive gland is removed. The remaining parathyroid glands are typically enough to keep hormone levels healthy.
Are there dietary changes that can help?
Getting enough calcium and vitamin D from food or supplements can help manage secondary hyperparathyroidism, but primary hyperparathyroidism usually needs medical or surgical treatment.
Can vitamin D deficiency cause OFC?
Yes. Severe, long-lasting vitamin D deficiency can lead to secondary hyperparathyroidism, which may eventually cause osteitis fibrosa cystica.
Is bone pain the only symptom?
No. Other symptoms include fatigue, nausea, constipation, and frequent urination caused by high calcium levels in the blood.
What tests are used to diagnose osteitis fibrosa cystica?
Blood tests measure parathyroid hormone, calcium, and other minerals. X-rays or CT scans then look for bone thinning, small fractures, and cyst-like holes in the bone.
Related Resources
Related reading on Rinnit:
References
Cleveland Clinic. Osteitis fibrosa cystica (OFC). Cleveland Clinic Health Library. Medically reviewed; last updated May 30, 2024. https://my.clevelandclinic.org/health/diseases/osteitis-fibrosa-cystica
Anagnostis P, Vaitsi K, Veneti S, et al. Efficacy of parathyroidectomy compared with active surveillance in patients with mild asymptomatic primary hyperparathyroidism: a systematic review and meta-analysis of randomized-controlled studies. J Endocrinol Invest. 2021;44(6):1127-1137 (published online 2020). PMID: 33074457. DOI: 10.1007/s40618-020-01447-7
Jacquet-Francillon N, Prevot N. Brown tumors in nuclear medicine: a systematic review. Ann Nucl Med. 2023;37(5):255-270. PMID: 36933117. DOI: 10.1007/s12149-023-01832-1
Medical disclaimer
This article is for informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have about a medical condition.
Comments