Fibrous Dysplasia

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Continuing Education Activity

Fibrous dysplasia is a typically benign bone lesion characterized by intramedullary fibro-osseous proliferation secondary to altered osteogenesis. The polyostotic form often presents in childhood. Malignant transformation is rare, and remote radiation therapy has been reported as a risk factor. McCune-Albright syndrome is a relatively rare condition featuring polyostotic fibrous dysplasia (often unilateral) with skin pigmentation lesions and endocrine dysfunction (often female precocious puberty). This activity examines how to properly evaluate fibrous dysplasia and highlights the role of the interprofessional team in caring for patients with this condition.


  • Review the history and physical exam of a patient with fibrous dysplasia.
  • Summarize the treatment of fibrous dysplasia.
  • Describe the evaluation of a patient suspected of having fibrous dysplasia.
  • Explain how the facilitation of interprofessional team education and discussion can optimize the effective detection of fibrous dysplasia and inform the need for subsequent evaluations.


Fibrous dysplasia is a typically benign bone lesion characterized by intramedullary fibro-osseous proliferation secondary to altered osteogenesis.[1] First introduced by Lichtenstein and Jaffe in 1942 and originally termed Jaffe-Lichtenstein syndrome, fibrous dysplasia can occur in monostotic form (single bone) or polyostotic form (multiple bones).[1] Fibro-osseous tissue replacing normal bone can result in complications including fractures or compression of adjacent soft tissues including neurovascular structures.[2] Monostotic fibrous dysplasia is often an asymptomatic clinical entity. The polyostotic form often presents in childhood. Adult presentation often occurs incidentally during imaging for an unrelated indication.[2] Fibro-osseous replacement of bone can lead to pathologic fracture, especially in weight-bearing bones or the upper extremities in athletes.[3] Malignant transformation is rare, and remote radiation therapy has been reported as a risk factor.[4] McCune-Albright syndrome is a relatively rare condition featuring polyostotic fibrous dysplasia (often unilateral) with skin pigmentation lesions and endocrine dysfunction (often female precocious puberty). Mazabraud syndrome is a very rare polyostotic variant that features coexistent single or multiple intramuscular myxomas.[5]


The etiology of fibrous dysplasia has been linked with a missense mutation in the GNAS1 gene on chromosome 20. Abnormal proliferation of fibrous tissue ensues following an activating mutation.[6]


Incidence has been estimated at 1 in 5,000 to 10,000.[7] Most commonly fibrous dysplasia is first diagnosed in children or young adults. There is not a gender predilection. Overall, fibrous dysplasia constitutes 5% of all benign bone lesions.[2] The monostotic form is the most frequent, accounting for 75% to 80% of fibrous dysplasia cases.[8]


Fibrous dysplasia has histologic elements of immature collagen and immature bone trabeculae forming a fibrocellular matrix.[9] Trabeculae are not rimmed by osteoblasts secondary to osteoblast maturation arrest and histologic transition from normal to abnormal bone is usually abrupt.[9]

History and Physical

Patients with monostotic fibrous dysplasia are often asymptomatic.  Occasionally patients may present with bone pain. Pathologic fracture with minor inciting trauma can also be a first presentation.[10] Pregnancy can increase disease activity and therefore increase the risk of pain and pathologic fracture.[11] History and physical examination may contribute little to disease evaluation in cases of asymptomatic osseous involvement. History should address the characteristics of bone tenderness, bony protuberance, osseous asymmetry, endocrine disturbance, and dermatologic complaints. A family history of bone lesions may be present in hereditary forms of fibrous dysplasia such as cherubism. Although malignant transformation is rare, it does occur in less than 1% of cases.[12] In a patient with known fibrous dysplasia, periodic evaluation for aggressive lesion growth should be performed.[13] McCune-Albright syndrome should be considered in the setting of hyperfunctioning endocrinopathy.

Physical exam has a minor role in evaluating lesions. In the setting of pain, focal palpation may increase pain with fractures. Visual inspection for skeletal deformities and asymmetries can provide clues to sites of involvement. Leg length discrepancy may indicate disease such as the classic shepherd’s crook deformity at the proximal femur.[14] Facial involvement can result in orbital asymmetry.[15] Other potential face complications include proptosis, frontal bossing, or enlargement of the mandible.[16]

Common sites of involvement subject to deformity are the ribs, long bones, and craniofacial structures. Less common sites include the hands, sternum, and spine.[17][18] In the setting of McCune-Albright syndrome, the physical examination should include an evaluation of the skin to asses for cafe au lait skin pigmentation. Skin acne may be a feature of endocrinopathy (Cushing syndrome).[19] A thorough physical examination to assess the endocrine system should be performed. This also includes the cardiopulmonary, gastrointestinal as well as thyroid evaluation.[20] Assessment of vision and hearing in the setting of craniofacial manifestation of fibrous dysplasia is also important.[2]


Imaging plays a chief role in the diagnosis and evaluation of the disease extent. Radiography should be utilized first in an evaluation. Advanced imaging such as computerized tomography (CT) and magnetic resonance imaging (MRI) can exclude other bone lesions; evaluate for soft tissue complications occurring from fractures, craniofacial neurovascular complications; and assess lesions for rare malignant transformation.[21] CT and MRI also have a role in the evaluation of adrenal hyperplasia, thyroid nodules, and pituitary tumors.[22][23] Classically, bone lesions have an internal ground glass matrix on radiographs and CT, but appearance can be varied with lytic and/or sclerotic components, possible bone expansion, and cortical thinning [12] Bowing deformities (including the femoral shepherd's crook deformity), discrepant limb length, and short stature secondary to premature fusion of growth plates can be characterized with imaging.[21] Bone scan demonstrating increased Technetium-99m radiotracer uptake may have a role in polyostotic cases to assess disease extent.[24] Finally, biopsy with histologic evaluation may be necessary in select cases when imaging features mimic malignant lesions.[14]

Treatment / Management

Monostotic fibrous dysplasia cases are often asymptomatic. Patients in this category can be followed periodically with assessment for new symptoms and radiographs.[25] Treatment is not required in asymptomatic cases. Adult medication therapy with bisphosphonates can alleviate bone pain and disease-associated osteoporosis.[10] Bisphosphonates inhibit osteoclastic bone resorption, preserving cortical bone mass and thereby reducing fracture risk.[26][27] Surgery may have a role in symptomatic fibrous dysplasia management. Surgical management includes internal fixation following pathologic fractures or prophylactic internal fixation in lesions weakening weight-bearing bones.[14] Additional surgical interventions include correction of extremity and spine deformities and limb length discrepancies.[14] Craniofacial surgery can play an important role in alleviating nerve compression symptoms.[28] Surgery may involve bone lesion curettage, bone grafting, and insertion of metallic fixation rods, plates, and screws.[14]

Differential Diagnosis

In the setting of polyostotic McCune-Albright syndrome, accurate assessment of the cafe au lait skin pigmentation lesions is important. Associated skin lesion borders have been described as serrated, which is in contrast to smooth skin lesion borders in neurofibromatosis.[11]

Fibrous dysplasia often has varied imaging presentation and osseous sites of involvement and therefore other bone diseases must often be considered. Monostotic radiologic appearance can mimic simple bone cyst, giant cell tumor, fibroxanthoma, osteoblastoma, hemangioma, osteofibrous dysplasia, and Paget disease.  Polyostotic appearance can mimic neurofibromatosis, hyperparathyroidism (Brown tumors), enchondromatosis, and eosinophilic granuloma.[25][11] Patient age, bone location (fibrous dysplasia has a predilection for the long bone diaphysis), presence of ground glass matrix, and non-aggressive appearance may be lesion features that favor fibrous dysplasia.[11] Bone biopsy does have a role if malignancy cannot be excluded following clinical and imaging work up.[14]


Usually fibrous dysplasia is monostotic and asymptomatic. In the cases of severe bone deformity, bowing may result in musculoskeletal dysfunction or accelerate development of osteoarthritis.[29] Spine lesions may predispose to scoliosis and subsequent functional limitations.[30] Craniofacial cases may have associated cranial nerve deficits including vision and hearing loss.[31][32] Malignant transformation to sarcoma is rare but can occur with a prior history of radiation therapy.[33]


  • Pediatric orthopedics
  • Orthopedics
  • Genetics

Deterrence and Patient Education

Patient education regarding the risk of fracture is important.[34] In cases of craniofacial disease, patients should be coached to monitor for evolving cranial nerve deficits including vision and hearing loss. In the setting of McCune-Albright syndrome, parents and the patient should be educated on the various manifestations of the syndrome and genetic counseling should be performed.[35] Routine visits to an endocrinologist should be incorporated to monitor for symptoms of endocrine dysfunction.

Enhancing Healthcare Team Outcomes

Managing fibrous dysplasia involves an interprofessional team approach, primarily with pediatrics/primary care, orthopedics, and radiology.  Genetics and endocrinology should be added for cases of McCune-Albright syndrome. Craniofacial involvement should prompt neurology, ophthalmology, audiology, and possible neurosurgery consultation.[3][36] Additional support from physical therapy and psychiatry in cases of disability or deformity may be warranted.[3]

Article Details

Article Author

Dawood Tafti

Article Editor:

Nathan D. Cecava


2/5/2022 8:50:24 AM

PubMed Link:

Fibrous Dysplasia



Schoenau E,Rauch F, Fibrous dysplasia. Hormone research. 2002     [PubMed PMID: 12065933]


DiCaprio MR,Enneking WF, Fibrous dysplasia. Pathophysiology, evaluation, and treatment. The Journal of bone and joint surgery. American volume. 2005 Aug     [PubMed PMID: 16085630]


Leet AI,Collins MT, Current approach to fibrous dysplasia of bone and McCune-Albright syndrome. Journal of children's orthopaedics. 2007 Mar     [PubMed PMID: 19308500]


Hansen MR,Moffat JC, Osteosarcoma of the Skull Base after Radiation Therapy in a Patient with McCune-Albright Syndrome: Case Report. Skull base : official journal of North American Skull Base Society ... [et al.]. 2003 May     [PubMed PMID: 15912163]


Munksgaard PS,Salkus G,Iyer VV,Fisker RV, Mazabraud's syndrome: case report and literature review. Acta radiologica short reports. 2013     [PubMed PMID: 24198959]


Robinson C,Collins MT,Boyce AM, Fibrous Dysplasia/McCune-Albright Syndrome: Clinical and Translational Perspectives. Current osteoporosis reports. 2016 Oct     [PubMed PMID: 27492469]


Pai B,Ferdinand D, Fibrous dysplasia causing safeguarding concerns. Archives of disease in childhood. 2013 Dec     [PubMed PMID: 23966029]


Riddle ND,Bui MM, Fibrous dysplasia. Archives of pathology     [PubMed PMID: 23276185]


Riminucci M,Liu B,Corsi A,Shenker A,Spiegel AM,Robey PG,Bianco P, The histopathology of fibrous dysplasia of bone in patients with activating mutations of the Gs alpha gene: site-specific patterns and recurrent histological hallmarks. The Journal of pathology. 1999 Jan     [PubMed PMID: 10365102]


Chapurlat RD,Gensburger D,Jimenez-Andrade JM,Ghilardi JR,Kelly M,Mantyh P, Pathophysiology and medical treatment of pain in fibrous dysplasia of bone. Orphanet journal of rare diseases. 2012 May 24     [PubMed PMID: 22640953]


Kransdorf MJ,Moser RP Jr,Gilkey FW, Fibrous dysplasia. Radiographics : a review publication of the Radiological Society of North America, Inc. 1990 May     [PubMed PMID: 2188311]


Adetayo OA,Salcedo SE,Borad V,Richards SS,Workman AD,Ray AO, Fibrous dysplasia: an overview of disease process, indications for surgical management, and a case report. Eplasty. 2015     [PubMed PMID: 25848443]


Ruggieri P,Sim FH,Bond JR,Unni KK, Malignancies in fibrous dysplasia. Cancer. 1994 Mar 1     [PubMed PMID: 8111708]


Stanton RP,Ippolito E,Springfield D,Lindaman L,Wientroub S,Leet A, The surgical management of fibrous dysplasia of bone. Orphanet journal of rare diseases. 2012 May 24     [PubMed PMID: 22640754]


Gupta S,Jain S,Newaskar V,Ali M, Craniofacial fibrous dysplasia with facial asymmetry, canted occlusion and open bite: a case report with 2 years follow-up. The journal of contemporary dental practice. 2014 Sep 1     [PubMed PMID: 25707839]


Sandhu SV,Sandhu JS,Sabharwal A, Clinicoradiologic perspective of a severe case of polyostotic fibrous dysplasia. Journal of oral and maxillofacial pathology : JOMFP. 2012 May     [PubMed PMID: 22923911]


Zorzin L,Palmieri G,Marrese C,Spagnoli LG, Polyostotic fibrous dysplasia involving the sternum. Clinical rheumatology. 1988 Mar     [PubMed PMID: 3261673]


Batista KT,Araújo HJ,Schwartzman UP, Monostotic fibrous dysplasia of the metacarpal: a case report. Revista brasileira de ortopedia. 2016 Nov-Dec     [PubMed PMID: 28050548]


Dean L, McCune-Albright Syndrome null. 2012     [PubMed PMID: 28520344]


Francis GL,Waguespack SG,Bauer AJ,Angelos P,Benvenga S,Cerutti JM,Dinauer CA,Hamilton J,Hay ID,Luster M,Parisi MT,Rachmiel M,Thompson GB,Yamashita S, Management Guidelines for Children with Thyroid Nodules and Differentiated Thyroid Cancer. Thyroid : official journal of the American Thyroid Association. 2015 Jul     [PubMed PMID: 25900731]


Fitzpatrick KA,Taljanovic MS,Speer DP,Graham AR,Jacobson JA,Barnes GR,Hunter TB, Imaging findings of fibrous dysplasia with histopathologic and intraoperative correlation. AJR. American journal of roentgenology. 2004 Jun     [PubMed PMID: 15149980]


O'Laughlin RL,Selinger SE,Moriarty PE, Pituitary adenoma in McCune-Albright syndrome: MR demonstration. Journal of computer assisted tomography. 1989 Jul-Aug     [PubMed PMID: 2745790]


Kirk JM,Brain CE,Carson DJ,Hyde JC,Grant DB, Cushing's syndrome caused by nodular adrenal hyperplasia in children with McCune-Albright syndrome. The Journal of pediatrics. 1999 Jun     [PubMed PMID: 10356155]


Zhibin Y,Quanyong L,Libo C,Jun Z,Hankui L,Jifang Z,Ruisen Z, The role of radionuclide bone scintigraphy in fibrous dysplasia of bone. Clinical nuclear medicine. 2004 Mar     [PubMed PMID: 15162988]


Bousson V,Rey-Jouvin C,Laredo JD,Le Merrer M,Martin-Duverneuil N,Feydy A,Aubert S,Chapurlat R,Orcel P, Fibrous dysplasia and McCune-Albright syndrome: imaging for positive and differential diagnoses, prognosis, and follow-up guidelines. European journal of radiology. 2014 Oct     [PubMed PMID: 25043984]


Shahnazari M,Yao W,Dai W,Wang B,Ionova-Martin SS,Ritchie RO,Heeren D,Burghardt AJ,Nicolella DP,Kimiecik MG,Lane NE, Higher doses of bisphosphonates further improve bone mass, architecture, and strength but not the tissue material properties in aged rats. Bone. 2010 May     [PubMed PMID: 19931661]


Zacharin M,O'Sullivan M, Intravenous pamidronate treatment of polyostotic fibrous dysplasia associated with the McCune Albright syndrome. The Journal of pediatrics. 2000 Sep     [PubMed PMID: 10969268]


Tan YC,Yu CC,Chang CN,Ma L,Chen YR, Optic nerve compression in craniofacial fibrous dysplasia: the role and indications for decompression. Plastic and reconstructive surgery. 2007 Dec     [PubMed PMID: 18090759]


Kushare IV,Colo D,Bakhshi H,Dormans JP, Fibrous dysplasia of the proximal femur: surgical management options and outcomes. Journal of children's orthopaedics. 2014 Dec     [PubMed PMID: 25409925]


Mancini F,Corsi A,De Maio F,Riminucci M,Ippolito E, Scoliosis and spine involvement in fibrous dysplasia of bone. European spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society. 2009 Feb     [PubMed PMID: 19130098]


Michael CB,Lee AG,Patrinely JR,Stal S,Blacklock JB, Visual loss associated with fibrous dysplasia of the anterior skull base. Case report and review of the literature. Journal of neurosurgery. 2000 Feb     [PubMed PMID: 10659026]


Boyce AM,Brewer C,DeKlotz TR,Zalewski CK,King KA,Collins MT,Kim HJ, Association of Hearing Loss and Otologic Outcomes With Fibrous Dysplasia. JAMA otolaryngology-- head     [PubMed PMID: 29192304]


Qu N,Yao W,Cui X,Zhang H, Malignant transformation in monostotic fibrous dysplasia: clinical features, imaging features, outcomes in 10 patients, and review. Medicine. 2015 Jan     [PubMed PMID: 25621678]


Han I,Choi ES,Kim HS, Monostotic fibrous dysplasia of the proximal femur: natural history and predisposing factors for disease progression. The bone     [PubMed PMID: 24788504]


Dumitrescu CE,Collins MT, McCune-Albright syndrome. Orphanet journal of rare diseases. 2008 May 19     [PubMed PMID: 18489744]


Bowers CA,Taussky P,Couldwell WT, Surgical treatment of craniofacial fibrous dysplasia in adults. Neurosurgical review. 2014 Jan     [PubMed PMID: 24221055]