Treatment for Fibrous Dysplasia
Bisphosphonate therapy is the treatment of choice for fibrous dysplasia, particularly for patients with bone pain, with intravenous pamidronate (180 mg every 6 months) being the most effective option for symptomatic relief.
Clinical Presentation and Diagnosis
Fibrous dysplasia (FD) is a rare skeletal disorder characterized by abnormal fibroblast and osteoblast proliferation with increased bone resorption. It presents in two main forms:
- Monostotic FD: Involves a single bone (more common)
- Polyostotic FD: Involves multiple bones
- McCune-Albright Syndrome: Polyostotic FD with endocrine abnormalities and café-au-lait skin pigmentation (approximately 3% of FD cases)
FD commonly affects the long bones, ribs, and craniofacial bones. Most cases are asymptomatic and discovered incidentally, but symptomatic cases present with:
- Bone pain
- Pathologic fractures
- Bone deformities
- Compression symptoms (especially in craniofacial involvement)
Treatment Algorithm
1. Asymptomatic Patients
- Clinical observation and patient education
- Regular follow-up to monitor for disease progression
- No specific treatment required
2. Symptomatic Patients
First-line Treatment: Bisphosphonates
Intravenous pamidronate: 180 mg every 6 months for adults 1
- Relieves bone pain in approximately 50% of patients
- Decreases bone resorption
- Improves radiological appearance in some cases
- Increases bone mineral density at affected sites
Alternative bisphosphonates:
- Alendronate (oral)
- Zoledronic acid (4 mg IV every 6 months) - though limited evidence suggests it may not provide substantial improvement over pamidronate in resistant cases 1
Supportive Treatments
- Calcium and vitamin D supplementation for patients with deficiency 1
- Phosphorus supplementation for patients with both FD and renal phosphate wasting 1
3. Surgical Management
Surgery is indicated for:
- Confirmatory biopsy
- Correction of deformity
- Prevention of pathologic fracture
- Eradication of symptomatic lesions
- Addressing compression symptoms
Cortical bone grafts are preferred over cancellous grafts due to superior physical qualities of remodeled cortical bone 2.
Treatment Efficacy and Monitoring
- Pain relief: Most consistent benefit of bisphosphonate therapy 1, 3, 4
- Biochemical markers: Decrease in bone turnover markers with treatment 4
- Radiological improvement: Filling of lytic lesions and/or thickening of cortices in approximately 50% of patients, though not consistently observed 1, 4
Important Considerations
Limited evidence base: Most treatment recommendations come from open studies without controls 1
Treatment limitations: Current therapies focus on symptom management and maintaining bone density rather than stopping disease progression 5
Long-term monitoring: Regular follow-up is essential as there is no therapy for preventing disease advancement
Malignant transformation: Though rare, patients should be monitored for this possibility 5
Treatment response variability: Individual response to bisphosphonates varies significantly
While bisphosphonates have shown efficacy in managing symptoms of fibrous dysplasia, randomized controlled trials are still needed to better establish optimal treatment protocols. The current approach focuses on symptom management rather than disease modification, with surgical intervention reserved for specific indications.