Calcific myonecrosis as a late complication of an open fracture

Abstracts Abstract: Introduction: dystrophic calcification or calcinosis generally develops within a few years of juvenile dermatomyositis (DM). Its prevalence varies from 6 to 50 percents. This condition is unusual in adult DM. the calcinosis occurs predominantly in sites that have been subject to friction or trauma such as elbows and knees. It is most often localized to the subcutaneous tissue but can also develop in the skin, fascia or muscle. The calcinosis seems to progress as long as there is active inflammatory disease and it is often treatment resistant. Several treatments may be tried such as diltiazem, probencid, alendronate, aluminum hydroxide and low dose warfarin, but none is proven benefit. The case: the case is a 51 years old female with diagnosis of DM from 7 years ago. She was on prednisolone 5 mg/d and methotrexate 7.5 mg/w and the disease was in remission. 1 year ago she felt pain in right gluteal region and gradually a hard mass in this region. She denied any trauma or injection to this area. In physical examinations right buttock is fewer larger than the other one and a hard tender mass palpated in right gluteous sized 5*7 cm. this mass not interfere with right hip motions. In radiography two calcifications seen in right buttock, one in gluteal muscle and the other in proximal right femur. Conclusions: this is a rare case of adult DM with calcification in right gluteal area. Soft tissue calcification in our case not responded to diltiazem,alendronate and aluminium hydroxide gel. This article is part of a Special Issue entitled ECTS 2012. Disclosure of interest: None Declared. doi:10.1016/j.bone.2012.02.550

PP362 Calcific myonecrosis as a late complication of an open fracture A. Michaela, S. Sajidb,⁎, R. Shavec, S. Buttb a Geriatrics Medicine Department, Russells Hall Hospital, Dudley, UK b Orthopaedic Department, Russells Hall Hospital, Dudley, UK c Radiology Department, Russells Hall Hospital, Dudley, UK Abstract: Case report: A 76 y male presented with a firm swelling on the lateral aspect of his right leg. He had an open right tibia and fibula fracture 58 years previously, which was treated conservatively. On examination he had a 4 cm nontender well-defined firm lump on the lateral aspect of his right leg. There was no neurovascular deficits. Blood count, liver functions, and ESR were normal. X-rays showed marked calcification in the muscles of the right leg and healed fractures of tibia and fibula. Ultrasound scan showed extensive calcific density within the soft tissues of posterior and lateral compartments. MRI revealed marked atrophy of the proximal calf muscles, suggesting previous compartment syndrome, and a distinct area of calcification separate from the bony skeleton. The atrophy of musculature and the pattern of calcification led to the diagnosis of calcific myonecrosis. The patient remained asymptomatic and was managed conservatively. Discussion: Originally described as a late complication of Volkman's ischaemic contracture, CM is a rare late complication of compartment syndrome or neurovascular injury. Calcification occurs predominately in the lower limb, most frequently the anterior compartment of the leg. There are case reports of the upper limb and the foot. CM typically manifests as a fusiform area of calcification on X-ray. MRI shows a well-circumscribed linear mass with peripheral calcification and a liquid centre, within a compartment or involving one particular muscle. There are case reports of erosion of neighbouring bones. Patients present 10 to 64 years after an injury. There is usually a history of trauma resulting in compartment syndrome or a history of muscle ischaemia. Peripheral nerve injury has been implicated in the development of CM. The pathogenesis of CM remains unclear. It is a benign condition. Differential diagnosis of soft tissue calcification include myositis ossificans, dermato/ polymyositis and neoplasms. MRI is the diagnostic modality of choice. Role of surgery is controversial.Some authors advocate excision. Some avoid any operative intervention if diagnosis is incidental as there is a high rate of complications including significant blood loss, chronic sinus formation and amputation. Conclusion: Calcific myonecrosis is a late sequela of compartment syndrome or neurovascular injury. It manifests as a fusiform area of calcification on X-ray. The pathophysiology is unclear. Operative intervention has a high rate of complication. This article is part of a Special Issue entitled ECTS 2012. Disclosure of interest: None Declared. doi:10.1016/j.bone.2012.02.551

PP363 Increasing levels of serum sclerostin, an osteocyte-expressed negative regulator of bone formation, are associated with atherosclerotic disease in type 2 diabetes S. Moralesa,b,⁎, B. García-Fontanaa, A. García-Martína, P. Rozas-Morenoc, J.A. García-Salcedoa,d, R. Reyes-Garcíaa, M. Muñoz-Torresa

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a Bone Metabolic Unit (RETICEF), Endocrinology Division, Hospital Universitario San Cecilio b Proteomic Research Service, Fundación para la Investigación Biosanitaria de Andalucía Oriental -Alejandro Otero- (FIBAO), Granada c Endocrinology Division, Hospital General de Ciudad Real, Ciudad Real d Molecular Biology, Instituto de Parasitología y Biomedicina “López Neyra” , Granada, Spain

Abstract: Objective: In vitro studies have shown that calcification induces vascular smooth muscle cells (VSMCs) to undergo an osteocytic phenotype transition. In vivo studies in diabetic murine models have demonstrated that sclerostin, an osteocyte-derived negative regulator of bone formation, is up-regulated during calcification of VSMCs. Our aim was to explore the hypothesis that increased circulating sclerostin levels are associated with atherosclerotic disease in patients with type 2 diabetes mellitus (T2DM). Methods: Cross-sectional study of 75 patients with T2DM (female: 45.3%, mean age 59 ± 5.7 years and male: 54.7%, mean age 57.4 ± 6.7 years). We evaluated intima–media thickness, and the prevalence of ischemic heart disease, atherosclerotic plaques and aortic calcifications. Serum sclerostin levels were determined by ELISA immunoassay. Results: Overall 58.6% of T2DM patients had atherosclerotic disease (AD), 37.3% had ischemic heart disease, 54.6% had abnormal intima–media thickness, 28.1% had carotid plaques and 34.7% had aortic calcifications. Serum sclerostin was significantly higher in T2DM males than in T2DM females (P b 0.001). Mean serum sclerostin was significantly higher (P = 0.006) in patients with AD (59.0 ± 26.2 pmol/L) compared with those without AD (44.8± 16.5 pmol/L). Sclerostin serum levels remained significantly higher in male patients with vs without AD (68.4± 25.0 pmol/L vs 51.6 ±21.6 pmol/L; P = 0.042). Also, higher concentrations of sclerostin were found in male patients with abnormal intima–media thickness (68.9± 26.7 pmol/L vs 47.1 ± 16.0 pmol/L; P = 0.004), carotid plaques (79.0 ± 23.7 pmol/L vs 49.0 ± 20.5 pmol/L; P b 0.001) and aortic calcifications (70.2 ± 28.9 pmol/L vs 50.7 ± 21.2 pmol/L; P = 0.034). Serum sclerostin levels were significantly higher in female patients with vs without abnormal intima–media thickness (44.5 ± 12.2 pmol/L vs 36.1 ± 8.05 pmol/L; P = 0.029) and aortic calcifications (48.7 ± 13.9 pmol/L vs 36.3 ± 7.74 pmol/L; P = 0.004). Linear regression analysis demonstrated that serum sclerostin levels are predictors of AD after adjusting for age, gender, BMI, creatinine, homocysteine, HbA1c, other cardiovascular risk factors and surrogate markers of cardiovascular disease (β = 0.305; P = 0.04). Conclusion: Serum sclerostin levels were positively associated with parameters of atherosclerosis, suggesting that sclerostin is up-regulated during the progress of atherosclerotic disease in T2DM patients. This work was funded by projects PI081302 and RD06/0013/1014. This article is part of a Special Issue entitled ECTS 2012. Disclosure of interest: None Declared.

doi:10.1016/j.bone.2012.02.552

PP364 Generation and characterization of a neuroblastoma cell line stably expressing the tissue-nonspecific alkaline phosphatase enzyme TNSALP S. Grasera,⁎, C. Hofmannb, F. Jakoba, B. Mentrupa a Orthopedic Center for Musculoskeletal Research b Children's Hospital, Section of Paediatric Rheumatology, Osteology, Immunology and Infectious Diseases, University of Wuerzburg, Wuerzburg, Germany Abstract: Hypophosphatasia (HPP) is a rare hereditary disease, caused by mutations in the ALPL gene, which encodes the tissue nonspecific alkaline phosphatase (TNSALP). Patients show altered skeletal and dental mineralization, differing in severity depending on the specific mutation. TNSALP is an ectoenzyme, which functions as a dimer and cleaves its extracellular substrates pyridoxal phosphate (PLP), phosphoethanolamine (PEA) and inorganic pyrophosphate (PPi) and promotes the formation of hydroxyapatite crystals, a crucial step in bone mineralization. Apart from the bone phenotype HPP may cause epilepsy and depression/anxiety. Distinct specific neurons in the brain show high expression of TNSALP according to literature data. To further unravel the role of TNSALP in brain function, we analyzed the enzyme TNSALP in the neuroblastoma cell line SH-SY5Y (ATCC: CRL-2266). The endogenous mRNA expression and enzyme activity of TNSALP is very low in SH-SY5Y cells. Therefore we established a stable cell line which over expresses this enzyme. Cells were lipofected with a linearized pcDNA3.1 vector (Invitrogen; Darmstadt Germany), including the coding region of the human ALPL gene, and were selected with geneticin. The stable integration of the transfected DNA was controlled by PCR with genomic DNA and vector-specific primers. The resulting increase of ALPL