Intra-medullary osteosclerosis of the tibia in children

BACKGROUND

Intra-medullary osteosclerosis of the tibia is a rare condition characterised by chronic pain due to diaphyseal hyperostosis with no detectable triggering factor. The main differential diagnoses are stress fracture and osteoid osteoma. Of the few cases reported to date, most were in adults. The objective of this study was to assess paediatric patients with intra-medullary osteosclerosis to determine whether the first visit provides sufficient information to establish the diagnosis and rule out both osteoid osteoma and stress fracture, whether a biopsy is required, and which treatment is optimal.

HYPOTHESIS

The diagnosis of intra-medullary osteosclerosis of the tibia can be made at the first visit.

PATIENTS AND METHODS

Seven paediatric patients, 4 males and 3 females, with a mean age of 11 years, were included in this retrospective study. We evaluated the clinical features, findings from imaging studies (standard radiographs, computed tomography, magnetic resonance imaging, and bone scintigraphy), and treatment outcomes.

RESULTS

At the first visit, all patients had a painful swelling at the middle of the shin and imaging study evidence of antero-lateral tibial cortical thickening extending into the medullary cavity; in 5 patients, a linear lucency was visible. No other bone abnormalities were seen. Treatments included non-operative measures, pinning, and nailing. None of these treatments provided permanent bone healing or pain relief, although transitory freedom from pain with or without radiological bone healing was achieved.

DISCUSSION

Intra-medullary osteosclerosis of the tibia is rarely reported and therefore probably underdiagnosed. Distinctive characteristics of the cortical and endosteal thickening include location at the antero-lateral mid-diaphysis and, in some cases, the concomitant presence of a linear lucency that can provide the early diagnosis. The distinctive radiological features allow differentiation from a stress fracture. The management is challenging.

LEVEL OF EVIDENCE

IV, retrospective observational study.

Use of apparent diffusion coefficient as a response biomarker in bone: effect of developing sclerosis on quantified values

OBJECTIVE

To investigate the effect of sclerosis on apparent diffusion coefficient measurements in bone metastases from prostate cancer undergoing treatment.

MATERIALS AND METHODS

Sixteen patients underwent CT scans and MRI at baseline and 12 weeks following commencement of chemotherapy. For each patient, up to five bone metastases were selected. Hounsfield units were measured on CT and apparent diffusion coefficient (ADC) was measured on diffusion weighted MRI at both time points. Correlations between changes in apparent diffusion coefficient and Hounsfield units were investigated.

RESULTS

Corresponding pre- and post-treatment apparent diffusion coefficient and Hounsfield units were available on 60 lesions from 16 patients. Overall, there was no significant correlation between changes in apparent diffusion coefficient with Hounsfield units. However, where changes in Hounsfield units increased by more than 50 %, there was a trend for an associated ADC rise.

CONCLUSIONS

Increasing sclerosis of bone metastases on treatment does not significantly impede diffusion.

Bone metabolic activity in hyperostosis cranialis interna measured with 18F-fluoride PET

Purpose

¹⁸F-Fluoride PET/CT is a relatively undervalued diagnostic test to measure bone metabolism in bone diseases. Hyperostosis cranialis interna (HCI) is a (hereditary) bone disease characterised by endosteal hyperostosis and osteosclerosis of the skull and the skull base. Bone overgrowth causes entrapment and dysfunction of several cranial nerves. The aim of this study is to compare standardised uptake values (SUVs) at different sites in order to quantify bone metabolism in the affected anatomical regions in HCI patients.

Methods

Nine affected family members, seven non-affected family members and nine non-HCI non-family members underwent ¹⁸F-fluoride PET/CT scans. SUVs were systematically measured in the different regions of interest: frontal bone, sphenoid bone, petrous bone and clivus. Moreover, the average ¹⁸F-fluoride uptake in the entire skull was measured by assessing the uptake in axial slides. Visual assessment of the PET scans of affected individuals was performed to discover the process of disturbed bone metabolism in HCI.

Results

¹⁸F-Fluoride uptake is statistically significantly higher in the sphenoid bone and clivus regions of affected family members. Visual assessment of the scans of HCI patients is relevant in detecting disease severity and the pattern of disturbed bone metabolism throughout life.

Conclusion

¹⁸F-Fluoride PET/CT is useful in quantifying the metabolic activity in HCI and provides information about the process of disturbed bone metabolism in this specific disorder. Limitations are a narrow window between normal and pathological activity and the influence of age. This study emphasises that ¹⁸F-fluoride PET/CT may also be a promising diagnostic tool for other metabolic bone disorders, even those with an indolent course.

Dysosteosclerosis presents as an "osteoclast-poor" form of osteopetrosis: comprehensive investigation of a 3-year-old girl and literature review

Dysosteosclerosis (DSS), an extremely rare dense bone disease, features short stature and fractures and sometimes optic atrophy, cranial nerve palsy, developmental delay, and failure of tooth eruption in infancy or early childhood consistent with osteopetrosis (OPT). Bone histology during childhood shows unresorbed primary spongiosa from deficient osteoclast action. Additionally, there is remarkable progressive flattening of all vertebrae and, by adolescence, paradoxical metaphyseal osteopenia with thin cortical bone. Reports of consanguinity indicate autosomal recessive inheritance, yet more affected males than females suggest X-linked recessive inheritance. We investigated a nonconsanguineous girl with DSS. Osteosclerosis was discovered at age 7 months. Our studies, spanning ages 11 to 44 months, showed weight at approximately 50th percentile, and length diminishing from approximately 30th percentile to -2.3 SD. Head circumference was +4 SD. The patient had frontal bossing, blue sclera, normal teeth, genu valgum, and unremarkable joints. Radiographs showed orbital and facial sclerosis, basilar thickening, bone-in-bone appearance of the pelvis, sclerotic long bone ends, and fractures of ribs and extremities. Progressive metaphyseal widening occurred as vertebrae changed from ovoid to flattened and became beaked anteriorly. A hemogram was normal. Consistent with OPT, serum parathyroid hormone (PTH) concentrations reflected dietary calcium levels. Serum bone alkaline phosphatase, osteocalcin, and TRACP-5b were subnormal. The iliac crest contained excessive primary spongiosa and no osteoclasts. No mutations were identified in the splice sites or exons for the genes encoding chloride channel 7, T-cell immune regulator 1, OPT-associated transmembrane protein 1, and monocyte colony-stimulating factor (M-CSF) and its receptor C-FMS, ANKH, OPG, RANK, and RANKL. Genomic copy-number microarray was unrevealing. Hence, DSS is a distinctive OPT of unknown etiology featuring osteoclast deficiency during early childhood. How osteopenia follows is an enigma of human skeletal pathobiology.

Sclerostin: current knowledge and future perspectives

In recent years study of rare human bone disorders has led to the identification of important signaling pathways that regulate bone formation. Such diseases include the bone sclerosing dysplasias sclerosteosis and van Buchem disease, which are due to deficiency of sclerostin, a protein secreted by osteocytes that inhibits bone formation by osteoblasts. The restricted expression pattern of sclerostin in the skeleton and the exclusive bone phenotype of good quality of patients with sclerosteosis and van Buchem disease provide the basis for the design of therapeutics that stimulate bone formation. We review here current knowledge of the regulation of the expression and formation of sclerostin, its mechanism of action, and its potential as a bone-building treatment for patients with osteoporosis.

[Focal osteosclerotic lesions of the jaws--a review focusing on diagnostic and therpeutic aspects]

The diagnosis of osteosclerotic lesions is sometimes quite challenging for the general dental practitioner. When having no clear reason for a sclerotic process in the jaw bone, the dentist is often left without a definite diagnosis and treatment plan. Additionally, the literature often mixes terms for sclerotic bone lesions in the mandible or maxilla, causing further confusion about classification, therapy and prognosis of these entities. Although osteosclerotic jaw lesions can arise in every decade of life, they often are encountered by chance on routine radiographic examinations. For further diagnosis these lesions are even referred for invasive procedures such as bone biopsies. Nevertheless, accurate knowledge about the pathogenesis, radiographic and clinical appearance of these lesions could already lead to a diagnosis without the need for further biopsies. The present review focuses on the focal osteosclerosis of the jaws, discussing diagnosis, treatment and important differential diagnoses.

Inflammatory demyelinating neuropathies and neuropathies associated with monoclonal gammopathies: treatment update

This review focuses on recent data regarding inflammatory demyelinating neuropathies and neuropathies associated with monoclonal gammopathies. We describe both acute and chronic inflammatory neuropathies, and we discuss conditions ranging from mostly cell-mediated to antibody-mediated disorders. These diseases are characterized by proximal and distal sensory motor involvement. Treatments are based on immune-modulation and/or immune-suppression. Work-up sequence and therapeutical modes are discussed in the light of recently published data, with a special interest on new treatment modalities.

Sclerosing bone disorders

Sclerosing bone disorders are a diagnostic challenge. However, hereditary sclerosing disorders often have characteristic radiological features that allow their diagnosis. Osteocondensation can result from decreased bone resorption; malignant recessive osteopetroses have been related to mutations in several genes necessary for osteoclast function and also, more recently, to osteoclast differentiation (RANK-L). Albers-Schonberg disease or autosomal-dominant osteopetrosis type II has the characteristic 'sandwich vertebrae' and 'bone within bone' radiological features. It has been related to mutation in chloride channel 7, which is necessary for osteoclast acidification. Osteocondensation can also be related to increased bone formation. Camurati-Engelman dysplasia is a disabilitating disorder with leg pain and weakness, and thickening of the diaphysis of long bones on x ray. It is due to activating mutations in the gene encoding TGF-beta, a growth factor that increases bone formation. Other less common recessive or dominant sclerosing disorders, such as endosteal hyperostosis, sclerostosis, van Buchen disease and high bone mass syndrome, are due to mutations in two genes (LRP5 and SOST) of the Wnt pathway that induce increased osteoblast activity. Recent elucidation of the molecular mechanism responsible for several hereditary diseases with osteocondensation has improved our comprehension of bone remodelling. It has allowed the discovery of new targets for the treatment of postmenopausal osteoporosis, some of which are already being investigated in clinical trials. Molecular mechanism for some hereditary osteocondensation remains to be discovered.

Sclerosing bone dysplasias: neurologic assessment and management

PURPOSE OF REVIEW

Sclerosing bone dysplasias are rare genetic disorders of bone remodeling in which excessive bone formation takes place, resulting in encroachment on neural structures. The infant usually appears normal at birth, and the first sign of a problem only comes when a neurologic deficit develops, usually in the form of an acute facial palsy. Although less than 300 cases have been published, these conditions should always be considered in the differential diagnosis of facial nerve palsy, especially in children.

RECENT FINDINGS

This review highlights the neurologic presentation and assessment as well as the management of sclerosing bone dysplasias. An exciting development is the recent discovery of the sclerosteosis (SOST) gene, which is involved with excessive bone formation in sclerosteosis and Van Buchem disease. Researchers in bone metabolism and pharmaceutical companies are now utilizing this knowledge to develop a medicine for osteoporosis.

SUMMARY

In children and young adults an acute facial palsy, especially if it is recurrent, as well as a conductive hearing loss may be the first sign of a sclerosing bone dysplasia.

Multiple myeloma presenting with widespread osteosclerotic lesions

Sclerotic lesions are rare in malignant monoclonal gammopathies, although they are occasionally associated with POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy and skin changes). In most cases, osseous lesions in POEMS syndrome present as an isolated sclerotic deposit or a combination of both lytic and sclerotic lesions. Diffuse osteosclerosis is extremely rare and may lead to the diagnosis of multiple myeloma, classically known to present as lytic lesions in the skeleton, with or without diffuse osteoporosis. We report a 74-year-old woman with widespread and substantial osteosclerotic lesions, associated with IgA-lambda myeloma, and with no other criteria for POEMS syndrome, and who was rapidly diagnosed with compression of the spinal cord. Detailed knowledge of imaging features in myeloma emphasises the need to consider plasma cell neoplasm in the differential diagnosis of any pattern of bone sclerosis. Although exceptional, multiple myeloma must be borne in mind in the presence of diffuse bone sclerosis.

Sclerosing osteomyelitis of Garré periostitis ossificans

Sclerosing osteomyelitis of Garré is a rare syndrome; the mandible is the most commonly affected bone segment in the cervicofacial region. This chronic disease is characterized by a nonsuppurative ossifying periostitis with subperiosteal bone formation, commonly reactive to a mild infection or irritation. The differential diagnosis must be made with similar clinical conditions with hard mandibular swelling associated with bony sclerosis. Presumptive diagnosis can be achieved by radiology, but such diagnosis must be confirmed by histology. The aim of therapy is to remove the cause when recognized, aided by an adequate antibiotic therapy. Clinical, radiographic, and histologic features are presented in this case report.

[Pycnodysostosis--common ancestor of some Danish patients. Examination and diagnosis based on molecular genetics]

Eight patients with pycnodysostosis from six Danish families were examined for mutations in the cathepsin K gene. Three different mutations are the cause of pycnodysostosis in the six families--five of whom come from Ringkøbing County and one from Vejle County. One mutation has a high frequency in the families from Ringkoebing County. The five families are related through a common ancestor, who introduced the mutation around the year 1100. The disease is described with respect to aetiology, symptoms, prognosis, diagnosis, and symptomatic treatment. Research in pycnodysostosis may bring important knowledge to the understanding of related diseases, such as osteoporosis.

Unusual jaw lesions in the paediatric and adolescent patient: a management challenge

While major maxillofacial pathology in the young patient is relatively uncommon, non-malignant conditions may pose a significant treatment dilemma due to their aggressive or unpredictable behaviour. Several such diseases managed by the Oral and Maxillofacial Surgery Unit at the Royal Children's Hospital of Melbourne have been selected for review. Illustrative case reports to highlight the principles of management are presented.

A model of myelofibrosis and osteosclerosis in mice induced by overexpressing thrombopoietin (mpl ligand): reversal of disease by bone marrow transplantation

We have previously shown that mice induced to overexpress thrombopoietin (TPO) by retroviral-mediated gene transfer into bone marrow (BM) cells develop myelofibrosis and osteosclerosis. It was speculated that these effects were secondary to TPO, resulting from high levels of megakaryocytes and platelets. Also, it was proposed that these mice represent a model for myelofibrosis and osteosclerosis. In this report, we show that levels of both transforming growth factor-beta 1 and platelet-derived growth factor are increased twofold to fivefold in the platelet-poor plasma of TPO overexpressing mice compared with control mice. These data suggest that the increased megakaryocytes produce elevated levels of these cytokines that lead to the pathogenesis of disease. Further, we retransplanted TPO overexpressing mice, at 40 to 42 weeks after primary transplantation, with normal BM cells. After the secondary transplantation, megakaryocytes and platelets returned to normal levels and the myelofibrosis and osteosclerosis were completely corrected. These data extend our initial studies of the effects of overexpression of TPO and show the potential use of this model to explore the underlying cause of myelofibrosis and osteosclerosis and potential treatments for these diseases.

Congenitally osteosclerotic (os/os) rabbits are not cured by bone marrow transplantation from normal littermates

The osteopetrotic (os) rabbit is a lethal mutation of autosomal recessive inheritance characterized by hypocalcemia, hypophosphatemia, fibrosis of marrow spaces, and ultrastructural abnormalities in both osteoclasts and osteoblasts. Procedures involving the transplantation of cells from normal hemopoietic tissues, which are sources of osteoclast precursors, are known to cure osteopetrosis in several mutations including some children. We tested the ability of transplanted bone marrow and/or spleen from normal littermates to reverse the skeletal sclerosis in os rabbits. Treatment of 15 neonatal mutants consisted of immunosuppression by whole-body irradiation followed by transplantation of normal bone marrow and/or spleen cell suspensions. This treatment failed to prolong life span or to cure osteopetrosis judged radiographically and histologically for up to 3 weeks posttreatment, the longest time of survival. These data indicate that transplantation of stem cells from multiple hemopoietic tissues, procedures known to cure osteopetrosis in other mutations, is not effective in the os rabbit. These results support the hypothesis that the skeletal microenvironment is not capable of supporting the development and function of normal osteoclasts in this mutation.

Condensing osteitis of the clavicle. Report of two cases and review of the literature

Condensing osteitis of the clavicle, better defined as aseptic enlarging osteosclerosis of the clavicle, is a rare and benign idiopathic lesion. It is probably of degenerative or mechanical origin, and is most commonly seen in middle-aged women as a tender swelling over the medial one-third of the clavicle. Although the clinical features may be confusing and nonspecific, the typical radiographic and histopathological findings will mostly lead to a correct diagnosis of this disorder. The differential diagnosis is quite extensive. Most difficult to differentiate are: avascular necrosis of the medial clavicular epiphysis, sternoclavicular orsteoarthritis, low-grade chronic osteomyelitis, sternocostoclavicular hyperostosis and Tietze's syndrome. The authors recommend a thorough physical examination and technical tests, not only in subjects with pain of the clavicle but also in those with shoulder pain only, especially in women who are in their fourth decade. Treatment with analgesic and anti-inflammatory medications may be variably effective. In refractory cases excisions of the medial one-third of the clavicle may be indicated to offer better relief of symptoms as well as to exclude malignancy.

[The POEMS syndrome]

The rare POEMS syndrome which combines hematology, bone, endocrine, neurology and skin manifestations, associated to a non-frequent osteosclerotic type of multiple myeloma is reviewed. The clinical, analytical, radiologic, immunologic, electrophysiologic and histopathologic features are detailed, as well as the different pathogenetical theories of its several manifestations, in an attempt to unify them. The different treatment schedules following the onset and corresponding prognostic are detailed.

Congenitally osteosclerotic (oc/oc) mice are resistant to cure by transplantation of bone marrow or spleen cells from normal littermates

The osteosclerotic mouse is a new, lethal recessive skeletal mutation which inherits osteopetrosis as an autosomal recessive. Affected mice are hypocalcemic and also have rickets. Osteoclasts are small and numerous with little evidence of function. This report examines the effects of bone marrow and spleen cell transplantation from normal littermates on survival and the radiographic appearance of the skeleton in 29 mutants. This procedure did not significantly prolong life or effect radiographic changes in the skeleton of most (27) recipients. However, two treated mutants lived for almost a year with radiographically normal skeletons. These variable responses to stem cell transplantation in an osteopetrotic mutant with rickets deserve further study.

The management of patients with back pain and idiopathic vertebral sclerosis

Twenty-two patients with severe back pain associated with radiologic evidence of vertebral sclerosis are reported. There were 19 women and 3 men; the average age was 42 years. Duration of pain averaged 4.3 years. The characteristic radiologic findings were diffuse sclerosis of the anterior inferior portion of the vertebral body and narrowing of the adjacent disc space. There was no extension of the sclerosis beyond the vertebral body, no paravertebral mass, and no loss of vertebral height. These radiologic characteristics, in conjunction with other clinical findings, should permit a diagnosis without the need for biopsy.

Therapeutic trial of plasma exchange in osteosclerotic myeloma associated with the POEMS syndrome

A patient with osteosclerotic myeloma and POEMS syndrome, unresponsive to pulse prednisone and melphalan therapy, was admitted to the hospital for a trial of plasma exchange therapy. The presentation included IgG lambda monoclonal gammopathy, peripheral neuropathy, hepatosplenomegaly, hyperpigmentation and thickening of the skin, edema, and tense ascites. Laboratory tests confirmed hypothyroidism, hypogonadism, and adrenal insufficiency. Six exchange procedures failed to affect the clinical course, and the patient died. Greater-than-one-plasma-volume exchanges (patient's measured plasma volume, 2,703 cc) were performed. When IgG and cholesterol removal were compared to the predicted removal, based on the volume of plasma removed, significantly less reduction in concentration than predicted was measured. IgG concentrations increased postapheresis and, at 2 weeks, three-fourths of the removed IgG had reaccumulated. A reduced efficiency of removal of both IgG and cholesterol can be explained by postulating increased vascular permeability with free exchange of soluble substances from one compartment to another. If an abnormal product is produced by the disease and is responsible for the clinical syndrome, a more intensive schedule of plasma exchange therapy may be needed to achieve a sustained depletion of the responsible soluble substance. Alternatively, neither increased vascular permeability or the clinical manifestations are responsive to removal of a soluble substance or are caused by a soluble substance produced by the malignancy.

Periapical condensing osteitis and endodontic treatment

Forty-nine roots of thirty-six teeth with the diagnosis of condensing osteitis were followed up by means of radiographs and patient files after endodontic treatment. The mean observation period was 4.3 years. Prior to endodontic treatment the periodontal membrane was widened on thirty-eight roots but on follow-up only on twelve. The periapical condensing osteitis showed total regression on thirty-six of the forty-nine roots. No condensing osteitis showed progress. The results show rebuilding of bone structures to normal appearance after endodontic treatment of periapical condensing osteitis.

Sclerosteosis: neurogenetic and pathophysiologic analysis of an American kinship

We studied an American kinship with sclerosteosis, an autosomal-recessive disorder of bone remodeling and bone overgrowth of the calvaria, skull base, and tubular bones. Unlike osteopetrosis, which is attributed to abnormal immune and osteoclast function as well as bone resorption, sclerosteosis appears to be primarily a disorder of osteoblast (bone formation) hyperactivity. Related to cranial vascular and neural foraminal narrowing and reduced intracranial volume, affected patients with sclerosteosis demonstrate frequent seventh nerve palsy, progressive optic and cranial neuropathies, mixed hearing loss, brainstem compression, intracranial hypertension with increased elastance, and sudden, premature death. Management should involve early childhood identification of homozygotes, monitoring and aggressive treatment of intracranial hypertension, and extensive bone removal from skull, posterior fossa, and cervical spine.

Reversal of severe bone marrow fibrosis and osteosclerosis following allogeneic bone marrow transplantation for chronic granulocytic leukaemia

Severe marrow fibrosis and osteosclerosis gradually disappeared after a 33-year-old woman received an allogeneic bone marrow transplantation (BMT) as experimental treatment for chronic granulocytic leukaemia. Serial biopsies demonstrate gradual resolution of dense reticulin fibrosis, collagen fibrosis and osteosclerosis, and restoration of normal marrow architecture after transplantation. These changes correspond with histological and cytogenetic evidence of normal marrow engraftment and sustained complete remission from chronic granulocytic leukaemia. In this case severe marrow infiltration with reticulin and collagen fibrosis as well as severe derangement of marrow architecture and obliteration of the medullary cavity by osteosclerosis was an entirely reversible process after allogeneic bone marrow transplantation, and did not prevent successful engraftment, haemopoietic and cytogenetic reconstitution and complete remission from chronic granulocytic leukaemia.

[Proceedings: The clinical effects of human growth hormone. Report on an international symposium of the German Kabi Corp. on February 15, 1975 in Munich]

Report of an International Symposion (Febr. 15, 1975, Munich). Human growth hormone (HGH) acts on proliferation of cartilage, the basal process of growth, by the way of somatomedine and changes in protein metabolism. Growth can be enhanced in hypopituitary dwardism and with higher dosage in other forms of failure to thrive. HGH also seems to have a beneficial effect in patients with muscular dystrophy as shown in a preliminary report but not in thrombocytopenia. First observations on patients with osteogenesis imperfecta and on patients with non healing fractures of the long bones (pseudarthroses) have shown significant improvement. Of importance are the reports on stopping severe gastric hemorrhage in patients with stress ulcera.