Fibrous dysplasia protuberans in a patient with McCune-Albright syndrome

Fibrous dysplasia protuberans refers to a benign fibro-osseous exophytic mass originating in the intra-medullary cavity of an adjacent bone. A case of fibrous dysplasia protuberans is hereby presented, manifesting as an exudative pleural effusion in a 49 years old male with history of McCune-Albright syndrome. This case represents the first reported case of fibrous dysplasia protuberans in a patient with McCune-Albright syndrome. Without a high index of suspicion, detailed radiographic imaging and meticulous histological examination, this benign bony excrescence is likely to be misdiagnosed, especially in a patient with no previous history of fibrous dysplasia.     

A giant cranial aneurysmal bone cyst associated with fibrous dysplasia

An aneurysmal bone cyst (ABC) is a rare, benign fibro-osseous lesion, considered a vascular phenomenon secondary to fibrous dysplasia or a giant-cell tumour, and occurs mainly in long bones and vertebrae. In this case report a 16-year-old male presented with massive epistaxis. He was admitted with a 3-year history of chronic rhinitis, headaches, right ocular pain and recurrent epistaxis. CT scans showed a predominantly cystic, expansive mass obstructing both nasal cavities, extending to all paranasal sinuses and both orbits, with evidence of anterior cranial fossa skull base destruction. The patient underwent a craniofacial resection of the tumour performed with an external approach and an immediate reconstruction of the dural defect. Histology confirmed the lesion was an ABC associated with fibrous dysplasia. The patient's recovery was complete. A large facial aneurysmal bone cyst can damage the facial skeleton and skull base, and requires excision by a combined external approach.     

Integrated anti-remodeling and anabolic therapy for the osteoporosis of Hajdu–Cheney syndrome

Hajdu–Cheney syndrome (MIM 102500) is a rare skeletal dysplasia marked by severe generalized osteoporosis and focal bone loss (acro-osteolysis). Osteoporosis treatment outcome has been reported only once previously. Reported herein is the biochemical and densitometric response to integrated anti-remodeling and anabolic therapy in a woman with Hajdu–Cheney syndrome. Results suggest dissociation of bone formation from bone resorption resulting in dramatic increases in bone mineral density without clinical evidence of activated osteoporosis. An erratum to this article can be found at     

Fibrous dysplasia of the temporal bone: the use of computerized tomography

Fibrous dysplasia of the temporal bone is a rare condition characterized histologically by proliferation of fibrous tissue with scattered trabeculae of immature bone. Eighteen cases of monostotic fibrous dysplasia of the temporal bone have been reported in the literature. The clinical course of temporal bone fibrous dysplasia is unpredictable. Potential complications include cholesteatoma, recurrence, and malignant transformation. Surgery has been the recommended treatment, but the indications, approach, and extent have not been clearly established. The introduction of computerized tomography with high-resolution bone reconstruction is a significant advance in the therapeutic approach to temporal bone fibrous dysplasia. It accurately defines the extent of the disease within the temporal bone, and periodic scanning will reveal any progression. This information can be used to resolve many surgical dilemmas and to minimize secondary complications. This article includes a comprehensive review of the literature on temporal bone fibrous dysplasia and summarizes a case in which computerized tomography was used.     

Fibrous dysplasia in combination with aneurysmal bone cyst of the occipital bone and the clivus: case report and review of the literature

OBJECTIVE AND IMPORTANCE: Fibrous dysplasia of the cranium is a relatively uncommon disorder that affects primarily the anterior cranial region; its occurrence in the cranial base in combination with aneurysmal bone cyst (ABC) constitutes an extremely rare condition, only two cases of which have been reported previously in the literature. It is important to recognize and treat these cases properly because of the special location in the cranial base and the possibility of neural structure impingement. CLINICAL PRESENTATION: We report the case of a 19-year-old man with a slowly enlarging mass of the occiput, with computed tomographic and magnetic resonance imaging revealing involvement of petrous and basisphenoid bone and growing ABC. INTERVENTION: Open biopsy confirmed the diagnosis of fibrous dysplasia. Partial excision of the lesion and removal of the ABC were performed in a second stage after embolization. CONCLUSION: ABC associated with fibrous dysplasia of the cranial base may enlarge rapidly after puberty and require excision. This is facilitated by preoperative embolization.     

Mazabraud's syndrome: intramuscular myxoma associated with fibrous dysplasia of bone

A 53 year old male with a large swelling on the medial aspect of his right thigh was referred with a presumptive diagnosis of soft tissue sarcoma. However, biopsy revealed intramuscular myxoma and X-rays and CT scans suggested fibrous dysplasia of adjacent bone. Angiography had shown an expanded, hypervascular, intramedullary lesion in the femur, and a large avascular soft tissue mass lying medially in the distal thigh. Fibrous dysplasia of the femur was confirmed on bone biopsy. Subsequently one large and two smaller intramuscular myxomata were excised, with an uneventful postoperative course. This case illustrates Mazabraud's syndrome: the rare association between benign intramuscular myxoma and fibrous dysplasia of bone.     

Cystic fibrous dysplasia in the long bone

Prominent osteolysis associated with "ground glass" density of fibrous dysplasia may indicate cystic change or sarcomatous transformation. This complication has been reported only sporadically in the long bones. This article presents clinical, radiographic, and pathologic findings, and outcome of simple curettage and bone graft observed in a series of 8 patients with prominent cystic fibrous dysplasia of the long bone. Magnetic resonance imaging features provide a basis for separation of benign cystic change from malignant transformation. However, biopsy is necessary to distinguish nonspecific cystic degeneration from secondary aneurysmal bone cyst. Simple curettage with allo-chip-bone graft is an effective treatment for cystic fibrous dysplasia.     

Monostotic fibrous dysplasia in the parietal bone: a case report

In this paper a case of monostotic fibrous dysplasia in the left parietal bone is described. This 51-year-old female was admitted to our hospital for a head injury on January 12, 1983, and a flat, painless hump (7 X 7cm) was incidentally found in the left parietal region. Plain x-ray film of the skull showed a multicystic lesion with slightly sclerotic margin in the left parietal bone, and outward bulging of the outer table without destruction of the inner table in tangential view. CT scan at the level of bone window clearly demonstrated the same abnormality and intradiploic mass separated by some bony septums. Angiography revealed no positive findings, but RI bone scan (99m Tc) showed an abnormal uptake in this lesion. On February 1, 1983, operation was performed to verify the nature of the lesion and for relief of the left-sided headache. Post operative course was uneventful. Histological findings of this mass were of inactive fibrous dysplasia with fibrous tissue replacing the normal bone and surrounded by island or scorlled edge of bones. Monostotic fibrous dysplasia in the cranial vault is rare. It is often possible to make diagnosis in this disease on the clinical course, plain x-ray film and CT scan showing cystic findings and outer table bulging, and RI scan demonstrating abnormal uptake.(ABSTRACT TRUNCATED AT 250 WORDS)     

Bone turnover in children and adolescents with McCune-Albright syndrome treated with pamidronate for bone fibrous dysplasia

Bone fibrous dysplasia is one of the main features of McCune-Albright syndrome, a rare genetic condition caused by constitutive activating mutations of Gs-protein and defined by skin dysplasia, bone fibrous dysplasia, and autonomous multiple endocrinopathies. Raised serum alkaline phosphatase (ALP) and urinary hydroxyproline levels indicating bone metabolic hyperactivity have been reported in these patients. Encouraging therapeutic results have been achieved, mainly in adults, with pamidronate, an aminobisphosphonate. In this study we investigate newer bone metabolic indices in a cohort of 11 children and adolescents treated with pamidronate. Tenfold increases of bone ALP and urinary pyridinoline cross-links were found and osteocalcin levels were twofold higher compared with reference values. After treatment, significant decreases in bone ALP and cross-links (Wilcoxon test P < 0.06) were found. Bone mineral density (BMD) significantly increased during treatment. There were signs of radiological healing as thickening of the cortical bone was found in some cases.     

Fibromyxoma of bone: a case report and review of the literature

In this study, a case of fibromyxoma of the proximal femur in a 59-year old woman is reported. The classification of this rare bone tumour is still a matter of debate and some investigators have suggested that these lesions represent a degenerative form of fibrous dysplasia. Some authors make a further distinction between fibromyxoma and myxoma of bone. In a review of 23 cases of fibromyxoma and five cases of myxoma, no differences in clinical, radiographic and biologic behaviour between fibromyxoma and myxoma were found. Apart from the age at diagnosis, the most important difference between fibromyxoma and myxoma was the degree of myxoid matrix. Therefore, we suggest that extragnathic myxoma is a regressive variant of extragnathic fibromyxoma and should be termed as the same entity. In contrast to monostotic fibrous dysplasia fibromyxoma / myxoma often causes pain and presents as a Lodwick IC lesion with a soft tissue mass. Therefore, fibromyxoma / myxoma should be distinguished from fibrous dysplasia because of its different clinical and radiographic features.     

Efficacy of growth hormone therapy for patients with skeletal dysplasia

Most patients with skeletal dysplasia show severe short stature. Surgical therapy has been attempted to correct bone deformities, but therapy for improving their severe short stature has been rarely attempted. We undertook a clinical trial of growth hormone (GH) therapy for patients with skeletal dysplasia accompanying severe short stature caused by achondroplasia (ACH), hypochondroplasia (HCH), pseudoachondroplasia (PSACH), spondyloepiphyseal dysplasia congenita (SED), or Schmid type metaphyseal dysplasia (MD). This study examined the efficacy of GH therapy on height increase and change of height SD score over a 1-year period in patients with skeletal dysplasia and showed a short-term efficacy for skeletal dysplasia. In ACH, HCH, and MD, GH had a significant effect on height gain. However, PSACH and SED showed no height gain efficacy; in cases of PSACH, height SD score was worse after therapy. Severe adverse events were not observed except in one SED case, in which scoliosis worsened and height did not increase. For patients with skeletal dysplasia, GH therapy is moderately effective for height gain. It is ineffective in cases with severe spinal deformities, however; although bone growth was promoted, the ligaments and matrix were too weak to support muscle tonus and the effects of gravity, resulting in worsened kyphosis and lordosis. These results clarify why GH therapy is ineffective for height gain. The pathogenic genes of skeletal dysplasia have recently been detected and consequently changes in bone formation have been investigated in detail. Careful consideration of indications for therapy and cautious observation during therapy are crucial when attempting to treat advanced bone deformities.     

Clinical approach to clarifying the mechanism of abnormal bone metabolism in McCune–Albright syndrome

Recent advances in our knowledge of the abnormal bone metabolism associated with McCune-Albright syndrome (MAS) is briefly reviewed. Polyostotic fibrous bone dysplasia and hypophosphatemia are well-known characteristics of MAS. To clarify the mechanism of bone dysplasia, an approach that uses human cells isolated from MAS patients was important. It is now clear that normal skeletal stromal cells without mutation of the Gsα protein are necessary for the presence of bone dysplasia and that exaggerated production of interleukin-6 by fibrous bone cells with mutation of the Gsα protein is linked to the increased number of osteoclasts in bone tissues. The observation of increased bone resorption by the increased osteoclasts is one of the reasons for using bisphosphonates to treat the bone lesions of MAS. The key observation of the mechanism of hypophosphatemia in MAS was in a clinical report, which suggested that the presence of some humoral factors regulate phosphate metabolism. Recently, the humoral factor that causes hypophosphatemia in MAS was clarified to be fibroblast-growth factor 23 (FGF-23), although the possibility of some other humoral factors was not excluded. This is because a humoral factor inhibiting intestinal phosphate transport is present in culture medium obtained from the cells derived from fibrous bone dysplasia. The abnormal vitamin D mechanism in response to hypophosphatemia in MAS patients also proved recently to be caused by the increased circulating FGF-23 levels. The lines of evidence described suggest that FGF-23 and other factors may coexist, causing hyperphosphaturia and impaired intestinal absorption of phosphate, respectively. Recipient of JSBMR Academic Award 2004     

Rapidly growing Brtl/+ mouse model of osteogenesis imperfecta improves bone mass and strength with sclerostin antibody treatment

Osteogenesis imperfecta (OI) is a heritable collagen-related bone dysplasia, characterized by brittle bones with increased fracture risk that presents most severely in children. Anti-resorptive bisphosphonates are frequently used to treat pediatric OI and controlled clinical trials have shown that bisphosphonate therapy improves vertebral outcomes but has little benefit on long bone fracture rate. New treatments which increase bone mass throughout the pediatric OI skeleton would be beneficial. Sclerostin antibody (Scl-Ab) is a potential candidate anabolic therapy for pediatric OI and functions by stimulating osteoblastic bone formation via the canonical Wnt signaling pathway. To explore the effect of Scl-Ab on the rapidly growing OI skeleton, we treated rapidly growing 3 week old Brtl/+ mice, harboring a typical heterozygous OI-causing Gly → Cys substitution on col1a1, for 5 weeks with Scl-Ab. Scl-Ab had anabolic effects in Brtl/+ and led to new cortical bone formation and increased cortical bone mass. This anabolic action resulted in improved mechanical strength to WT Veh levels without altering the underlying brittle nature of the material. While Scl-Ab was anabolic in trabecular bone of the distal femur in both genotypes, the effect was less strong in these rapidly growing Brtl/+ mice compared to WT. In conclusion, Scl-Ab was able to stimulate bone formation in a rapidly growing Brtl/+ murine model of OI, and represents a potential new therapy to improve bone mass and reduce fracture risk in pediatric OI.     

Fibromyxoma of the axis

Fibromyxoma of bone is a rare benign tumor of fibrous tissue origin. The typical location is the jaws. Sporadic extragnathic cases have been reported, but fibromyxoma of the spine has not been reported. The histological appearance of fibromyxoma is benign and includes abundant extracellular fibrous and myxoid stroma with varying amounts of calcification and ossification. Myxoid changes are usually extensive. Extragnathic fibromyxoma of bone should be distinguished from benign cartilage-forming bone tumors, such as chondromyxoid and myxoid chondrosarcoma and myxoma of bone. It has also been suggested that fibromyxoma is a variant of myxoid fibrous dysplasia, whereas other authors reported extragnathic fibromyxoma resulting from myxoid degeneration of bone tumors, such as chondrosarcoma or fibrosarcoma. The overtreatment of patients with fibromyxoma of bone due to an aggressive imaging appearance should be avoided; the prognosis is excellent compared with the jaw variant and depends on the location and extent of the tumor. This article describes a case of a 21-year-old woman with fibromyxoma of bone originating from the spinous process of the axis. Clinical examination showed a tender mass in the midline of the posterior aspect the neck and slight limitation of neck range of motion; neurologic examination was normal. Diagnosis was obtained with a preoperative biopsy. Marginal excision of the lesion with posterior laminectomy of the axis was performed. The facets were preserved, and no fusion was performed. At last follow-up 2 years after diagnosis and treatment, the patient was asymptomatic with no evidence of local recurrence.     

Outcomes following trochleoplasty for patellar instability with trochlear dysplasia: a systematic review

Trochleoplasty is a procedure to deepen the trochlear groove in patients with trochlear dysplasia. This systematic review evaluates the clinical and radiological outcomes following trochleoplasty for patellar instability due to trochlear dysplasia. An electronic literature search was performed using the AMED, British Nursing Index, CINAHL, Cochrane, EMBASE, ovid Medline, physiotherapy evidence database (PEDro), PsycINFO, Pubmed and Zetoc databases from their inception to August 2007. All English language, human subject clinical studies, detailing the clinical and/or radiological outcomes of patellar instability patients following a trochleoplasty were included. Six papers were reviewed. Two independent reviewers appraised each paper using the CASP tool. Trochleoplasty was shown to be a safe and effective procedure to correct patellar instability in trochlear dysplasia patients. However, the evidence-base currently has a number of methodological limitations. Accordingly this review’s findings should be viewed with caution. Recommendations for further study are made to develop the evidence-base.     

Hadju-Cheney syndrome: response to therapy with bisphosphonates in two patients.

Hadju-Cheney syndrome is characterized by short stature, distinctive facies, and a slowly progressive skeletal dysplasia including acro-osteolysis. Autosomal dominant inheritance is typical, but the genetic defect and molecular pathogenesis of the syndrome are unknown. Osteoporosis with atraumatic fracture is a frequent finding, and previous studies have documented biochemical and morphometric evidence of high bone turnover. Here, we report the clinical details and response to therapy with bisphosphonates in two patients (mother and son) with Hadju-Cheney syndrome and postulate that osteoclast-mediated bone resorption is important in the generalized osteoporosis commonly associated with this condition.     

CD99 positive adamantinoma of the ulna with ipsilateral discrete osteofibrous dysplasia

An adamantinoma is a rare, low-grade malignant, osteolytic bone tumor occurring predominantly in the diaphysis of the tibia. Osteofibrous dysplasia has been suggested as a precursor lesion to adamantinoma. Evidence for the relationship between these two tumors is based on their similar histologic features, immunohistochemistry, shared clonal abnormalities, overlapping skeletal distribution, and simultaneous occurrence in the tibia and fibula. The ulna is an unusual site of involvement by adamantinoma and osteofibrous dysplasia. Simultaneous involvement of the ulna by adamantinoma and ossifying fibroma has not been previously reported. A case is presented of an adamantinoma of the distal ulna with unique pathologic features occurring with an ipsilateral discrete focus of osteofibrous dysplasia as additional evidence of the relationship between these two lesions.     

Radiographic characteristics of fibrous dysplasia of the clivus: a case report and review of the literature

Whereas fibrous dysplasia is a well-known, developmental skeletal disorder with a benign clinical course, fibrous dysplasia of the clivus is extremely rare and has seldom been reported. Differentiating this benign entity from more aggressive diseases involving the clivus is important for the proper management of lesions in this area. We here report a case of fibrous dysplasia of the clivus and discuss its radiographic features. The patient was 55-year-old male who had suffered from headache for months. Physical and neurological examinations found no abnormalities. The computed tomographic (CT) scan and magnetic resonance imaging (MRI) showed an abnormal mass lesion in the lower of the third clivus. On CT scan, the mass lesion exhibited a ground-glass appearance. The lesion was detected as hypointense and a mixture of hyperintense and isointense areas on T1-weighted and T2-weighted MRI, respectively. Heterogenous enhancement was noted after infusion of GD-DTPA. The patient underwent a transsphenoidal resection of the mass and the histopathologic diagnosis was fibrous dysplasia.     

Uncemented acetabular components with bulk femoral head autograft for acetabular reconstruction in developmental dysplasia of the hip: results at five to twelve years.

BACKGROUND: Anterolateral acetabular bone deficiency is one of the technical problems associated with total hip arthroplasty in patients with developmental hip dysplasia. The purpose of this study was to evaluate the results of one method of acetabular reconstruction for hip dysplasia-placement of an uncemented socket in conjunction with a bulk femoral head autograft. METHODS: Forty-four hips in thirty-five patients (twenty-nine female and six male; average age, thirty-nine years) with developmental hip dysplasia were treated with primary total hip arthroplasty with use of an uncemented porous-coated titanium cup fixed with screws and an autogenous bulk femoral head graft. The patients were followed clinically in a prospective fashion for five to 12.3 years (mean, 7.5 years), and radiographs were analyzed retrospectively. RESULTS: Four acetabular components were revised: two, because of severe polyethylene wear and osteolysis; one, because of aseptic loosening; and one, because of fracture of the acetabular shell. The mean Harris hip score for the unrevised hips improved from 51 points preoperatively to 91 points postoperatively. No unrevised socket had definite radiographic evidence of loosening. Forty-three of the forty-four hips had no radiographic evidence of resorption of the graft or had radiographic evidence of resorption limited to the nonstressed area of the graft lateral to the edge of the cup. CONCLUSIONS: This method of reconstruction provided reliable acetabular fixation and appeared to restore acetabular bone stock in patients with developmental hip dysplasia. We use this technique for patients with moderate anterolateral acetabular bone deficiency requiring total hip arthroplasty.