Propositions pratiques d'utilisation des ultrasons quantitatifs osseux dans le management de l'ostéoporose [Practical proposals for the use of quantitative bone ultrasound in the management of osteoporosis]

As an emerging alternative to DXA, there is a growing interest in the use of quantitative ultrasound (QUS) measurements for the non invasive assessment of fracture risk in the management of osteoporosis. While the potential of QUS in the management of osteoporosis have been highly recognized by the scientific community and granted by the majority of the international bone disease organizations, it becomes important to develop strategies how to use ultrasound clinically. Our paper is highlighting Swiss operational clinical propositions for 2 QUS devices sold in Switzerland, on how to use the QUS in the management of osteoporosis.

Methicillin-susceptible Staphylococcus aureus clonal complex 398: high prevalence and geographical heterogeneity in bone and joint infection and nasal carriage.

The prevalence of clonal complex (CC) 398 methicillin-susceptible Staphylococcus aureus (MSSA) was unexpectedly high among bone and joint infections (BJIs) and nasal-colonizing isolates in France, with surprising geographical heterogeneity. With none of the major, most-known staphylococcal virulence genes, MSSA CC398 BJI was associated with lower biological inflammatory syndrome and lower treatment failure rates.

Biofilm formation by staphylococci on fresh, fresh-frozen and processed human and bovine bone grafts.

Biofilm formation is a multi-step process influenced by surface properties. We investigated early and mature biofilm of Staphylococcus aureus on 4 different biological calcium phosphate (CaP) bone grafts used for filling bone defects. We investigated standardised cylinders of fresh and fresh-frozen human bone grafts were harvested from femoral heads; processed humanand bovine bone grafts were obtained preformed. Biofilm formation was done in tryptic soy broth (TSB) using S. aureus (ATCC 29213) with static conditions. Biofilm density after 3 h (early biofilm) and 24 h (mature biofilm) was investigated by sonication and microcalorimetry. After 3 h, bacterial density was highest on fresh-frozenandfresh bone grafts. After 24 h, biofilm density was lowest on freshbone grafts (p < 0.001) compared to the other 3 materials, which did not differ quantitatively (p > 0.05). The lowest increase in bacterial density was detected on fresh bone grafts (p < 0.001). Despite normal shaped colonies, we found additional small colonies on the surface of the fresh and fresh-frozen samples by sonication. This was also apparent in microcalorimetric heat-flow curves. The four investigated CaP bone grafts showed minor structural differences in architecture but marked differences concerning serum coverage and the content of bone marrow, fibrous tissue and bone cells. These variations resulted in a decreased biofilm density on freshand fresh-frozenbone grafts after 24 h, despite an increased early biofilm formation and might also be responsible for the variations in colony morphology (small colonies). Detection of small colony variants by microcalorimetry might be a new approach to improve the understanding of biofilm formation.

Peri-prosthetic stress fractures after reversed shoulder arthroplasty

Introduction: Reversed shoulder prostheses have a semi-congruent design. Furthermore, the center of rotation is inferiorly displaced and a significant tension in the deltoid is often necessary to ensure the joint stability. Consequently, stress transmitted to peri-prosthetic bone may be increased, and could lead to stress fractures. We review a series of patients after reversed shoulder arthroplasty (RSA) and look specifically at the occurrence of postoperative peri-prosthetic stress fractures. Methods: Between 2001 and 2006, 46 consecutive RSA were performed. There were 26 women and 20 men with a mean age of 74 years (53-86). All had preoperative MRI or CT-scan, which did not reveal any fracture. All had a delto-pectoral approach with standard rehabilitation. Review was performed at a mean follow up of 30 months (6-60), and consisted of clinical and radiological (plain X-rays) examinations. Every time a fracture was suspected or in case of recurrent unexpected pain, CT-scan evaluations were performed. The occurrence of peri-prosthetic fractures was looked for. Results: Three patients (7%) sustained a scapular fracture (1 spinal and 2 acromial) without any trauma, between 3 and 6 months after the RSA. Furthermore, one of these patients developed 3 months later a spontaneous clavicular fracture, leading to an overall stress fracture rate of 9%. The four fractures were treated conservatively. Three malunions and one acromial non-union occurred. The range of motion in abduction and flexion decreased significantly after the fracture and stayed limited in all cases. All the three patients reported a recurrence of pain. Conclusion: Peri-prosthetic stress fractures, especially in the acromion and in the spine of the scapula are not unusual after RSA. The etiology is not well known. The increase of stress in peri-prosthetic bone may be due to the semi-congruent design and to an overtension of the deltoid. The management of this complication stays difficult. The conservative treatment leads to mal- or non-union, with persistent pain and limited range of motion.

Interaction between calcium intake and menarcheal age on bone mass gain: an eight-year follow-up study from prepuberty to postmenarche.

Both late menarcheal age and low calcium intake (Ca intake) during growth are risk factors for osteoporosis, probably by impairing peak bone mass. We investigated whether lasting gain in areal bone mineral density (aBMD) in response to increased Ca intake varies according to menarcheal age and, conversely, whether Ca intake could influence menarcheal age. In an initial study, 144 prepubertal girls were randomized in a double-blind controlled trial to receive either a Ca supplement (Ca-suppl.) of 850 mg/d or placebo from age 7.9-8.9 yr. Mean aBMD gain determined by dual energy x-ray absorptiometry at six sites (radius metaphysis, radius diaphysis, femoral neck, trochanter, femoral diaphysis, and L2-L4) was significantly (P = 0.004) greater in the Ca-suppl. than in the placebo group (27 vs. 21 mg/cm(2)). In 122 girls followed up, menarcheal age was recorded, and aBMD was determined at 16.4 yr of age. Menarcheal age was lower in the Ca-suppl. than in the placebo group (P = 0.048). Menarcheal age and Ca intake were negatively correlated (r = -0.35; P < 0.001), as were aBMD gains from age 7.9-16.4 yr and menarcheal age at all skeletal sites (range: r = -0.41 to r = -0.22; P < 0.001 to P = 0.016). The positive effect of Ca-suppl. on the mean aBMD gain from baseline remained significantly greater in girls below, but not in those above, the median of menarcheal age (13.0 yr). Early menarcheal age (12.1 +/- 0.5 yr): placebo, 286 +/- 36 mg/cm(2); Ca-suppl., 317 +/- 46 (P = 0.009); late menarcheal age (13.9 +/- 0.5 yr): placebo, 284 +/- 58; Ca-suppl., 276 +/- 50 (P > 0.05). The level of Ca intake during prepuberty may influence the timing of menarche, which, in turn, could influence long-term bone mass gain in response to Ca supplementation. Thus, both determinants of early menarcheal age and high Ca intake may positively interact on bone mineral mass accrual.

Development of Ewing's sarcoma from primary bone marrow-derived mesenchymal progenitor cells.

Ewing's sarcoma is a member of Ewing's family tumors (EFTs) and the second most common solid bone and soft tissue malignancy of children and young adults. It is associated in 85% of cases with the t(11;22)(q24:q12) chromosomal translocation that generates fusion of the 5' segment of the EWS gene with the 3' segment of the ETS family gene FLI-1. The EWS-FLI-1 fusion protein behaves as an aberrant transcriptional activator and is believed to contribute to EFT development. However, EWS-FLI-1 induces growth arrest and apoptosis in normal fibroblasts, and primary cells that are permissive for its putative oncogenic properties have not been discovered, hampering basic understanding of EFT biology. Here, we show that EWS-FLI-1 alone can transform primary bone marrow-derived mesenchymal progenitor cells and generate tumors that display hallmarks of Ewing's sarcoma, including a small round cell phenotype, expression of EFT-associated markers, insulin like growth factor-I dependence, and induction or repression of numerous EWS-FLI-1 target genes. These observations provide the first identification of candidate primary cells from which EFTs originate and suggest that EWS-FLI-1 expression may constitute the initiating event in EFT pathogenesis.

Sustained improvement in left ventricular function after bone marrow derived cell therapy in patients with acute ST elevation myocardial infarction. A 5-year follow-up from the Stem Cell Transplantation in Ischaemic Myocardium Study.

BACKGROUND: Intracoronary injection of autologous bone marrow-derived mononucleated cells (BM-MNC) may improve LV function shortly after acute ST elevation myocardial infarction (STEMI), but little is known about the long-term durability of the treatment effect. METHODS: In a single-centre trial a total of 60 patients with acute anterior STEMI, successful reperfusion therapy and a left ventricular ejection fraction (LVEF) of <50% were screened for the study. 23 patients were actively treated with intracoronary infusion of BM-MNC within a median of 3 days. The open-label control group consisted of 19 patients who did not consent to undergo BM-MNC treatment but agreed to undergo regular clinical and echocardiographic follow-up for up to 5 years after AMI. RESULTS: Whereas at 4 months there was no significant difference between the increase in LVEF in the BM-MNC group and the control group (+7.0%, 95%CI 3.6; 10.4) vs. +3.9%, 95%CI -2.1; 10), the absolute increase at 5 years remained stable in the BM-MNC but not in the control group (+7.95%, 95%CI 3.5; 12.4 vs. -0.5%, 95%CI -5.4; 4.4; p for interaction between groups = 0.035). DISCUSSION: In this single-centre, open-labelled study, intracoronary administration of BM-MNC is feasible and safe in the short term. It is also associated with sustained improvement of left ventricular function in patients with acute myocardial infarction, encouraging phase III studies to examine the potential BM-MNC effect on clinical outcome.

Can the trabecular bone score be considered as a major clinical risk factor of osteoporotic fractures? A meta-like analysis.

To have an added value over BMD, a CRF of osteoporotic fracture must be predictable of the fracture, independent of BMD, reversible and quantifiable. Many major recognized CRF exist. Out of these factors many of them are indirect factor of bone quality. TBS predicts fracture independently of BMD as demonstrated from previous studies. The aim of the study is to verify if TBS can be considered as a major CRF of osteoporotic fracture. Existing validated datasets of Caucasian women were analyzed. These datasets stem from different studies performed by the authors of this report or provided to our group. However, the level of evidence of these studies will vary. Thus, the different datasets were weighted differently according to their design. This meta-like analysis involves more than 32000 women (≥50years) with 2000 osteoporotic fractures from two prospective studies (OFELY&MANITOBA) and 7 cross-sectional studies. Weighted relative risk (RR) for TBS was expressed for each decrease of one standard deviation as well as per tertile difference (TBS=1.300 and 1.200) and compared with those obtained for the major CRF included in FRAX®. Overall TBS RR obtained (adjusted for age) was 1.79 [95%CI-1.37-2.37]. For all women combined, RR for fracture for the lowest compared with the middle TBS tertile was 1.55[1.46-1.68] and for the lowest compared with the highest TBS tertile was 2.8[2.70-3.00]. TBS is comparable to most of the major CRF and thus could be used as one of them. Further studies have to be conducted to confirm these first findings.

Intra-articular osteoid osteoma of the knee: clinical and therapeutical particularities

The intra-articular osteoid osteoma (10-13% of the cases) is often difficult to identify. They present frequent atypical clinical signs and radiological images that eventually lead to inadequate treatment. For example, it has been observed that this pathology leads to inappropriate arthroscopies (up to 40%). Meniscal tear and then osteochondritis were initially suspected on a patient with an intra-articular osteoid osteoma at the tibia level. For the treatment, any damage of the cartilage has to be avoided. Thermoablation with radiofrequency is the treatment of choice

Let-7a Is a Direct EWS-FLI-1 Target Implicated in Ewing's Sarcoma Development.

Ewing's sarcoma family tumors (ESFT) are the second most common bone malignancy in children and young adults, characterized by unique chromosomal translocations that in 85% of cases lead to expression of the EWS-FLI-1 fusion protein. EWS-FLI-1 functions as an aberrant transcription factor that can both induce and suppress members of its target gene repertoire. We have recently demonstrated that EWS-FLI-1 can alter microRNA (miRNA) expression and that miRNA145 is a direct EWS-FLI-1 target whose suppression is implicated in ESFT development. Here, we use miRNA arrays to compare the global miRNA expression profile of human mesenchymal stem cells (MSC) and ESFT cell lines, and show that ESFT display a distinct miRNA signature that includes induction of the oncogenic miRNA 17-92 cluster and repression of the tumor suppressor let-7 family. We demonstrate that direct repression of let-7a by EWS-FLI-1 participates in the tumorigenic potential of ESFT cells in vivo. The mechanism whereby let-7a expression regulates ESFT growth is shown to be mediated by its target gene HMGA2, as let-7a overexpression and HMGA2 repression both block ESFT cell tumorigenicity. Consistent with these observations, systemic delivery of synthetic let-7a into ESFT-bearing mice restored its expression in tumor cells, decreased HMGA2 expression levels and resulted in ESFT growth inhibition in vivo. Our observations provide evidence that deregulation of let-7a target gene expression participates in ESFT development and identify let-7a as promising new therapeutic target for one of the most aggressive pediatric malignancies.

Trabecular Bone Score Helps Classifying Women At Riskof Fracture Prospectively In The Ofely Study

Objectives: Trabecular Bone Score (TBS, Med-Imaps, France) is an index of bone microarchitecture calculated from antero-posterior spine DXA scan and reported to be associated with fracture in prior case-control studies and in a large prospective study with the Prodigy DXA device. Our aim was to assess the ability of TBS to predict incident fracture and improve the classification of fracture prospectively in the OFELY study.Materials/Methods: TBS was assessed in 564 postmenopausal women (66±8 years old) from the OFELY cohort, who had a spine DXA scan (QDR 4500A, Hologic, USA) between year 2000 and 2001. During a mean follow up of 7.8±1.3 years, 94 women sustained a fragility fracture.Results: At the time of baseline DXA scan, women with incident fracture were significantly older (70±9 vs. 65± 8 years), had a lower spine BMD (T-score: −1.9±1.2 vs. −1.3±1.3, p<0.001) and spine TBS (−3.1%, p<0.001) than women without incident fracture. After adjustment for age, BMI and the presence of prevalent fracture, the magnitude of fracture prediction was similar for spine BMD (OR=1.42 [1.11;1.82] per SD decrease [95% CI]) and TBS (OR=1.34 [1.04;1.74]) but the combination of TBS and spine BMD did not improve fracture prediction. Spine BMD and TBS were both correlated with age (respectively r=−0.17 and −0.49, p<0.001) and correlated together with 39% of TBS explained by spine BMD (r=0.63, p<0.001). When using the WHO classification, 38% of the fractures occurred in osteoporotic (fracture rate=29%), 47% in osteopenic (fracture rate=16%) and 15% in women with T-score >−1 (fracture rate=9%). By classifying our population in tertiles of TBS, we found that 47% of the fractures occurred in the lowest tertile of TBS (fracture rate=23%) and 39% of the fracture that occurred in osteopenic women were in the lowest tertile of TBS.Conclusions: Spine BMD and TBS predicted fractures equally well. The addition of TBS to spine BMD added only limited information on fracture risk prediction in our cohort when considering the all range of BMD. Nevertheless combining the osteopenic T-score and the lowest TBS helped defining a subset of osteopenic women at higher risk of fracture.Disclosure of Interest: None declared.

The effects of nutrition, puberty and dancing on bone density in adolescent ballet dancers.

Ballet dancers have on average a low bone mineral content (BMC), with elevated fracture-risk, low body mass index (BMI) for age (body mass index, kg/m2), low energy intake, and delayed puberty. This study aims at a better understanding of the interactions of these factors, especially with regard to nutrition. During a competition for pre-professional dancers we examined 127 female participants (60 Asians, 67 Caucasians). They averaged 16.7 years of age, started dancing at 5.8 years, and danced 22 hours/week. Assessments were made for BMI, BMC (DXA), and bone mineral apparent density (BMAD) at the lumbar spine and femoral neck, pubertal stage (Tanner score), and nutritional status (EAT-40 questionnaire and a qualitative three-day dietary record). BMI for age was found to be normal in only 42.5% of the dancers, while 15.7% had a more or less severe degree of thinness (12.6% Grade2 and 3.1% Grade 3 thinness). Menarche was late (13.9 years, range 11 to 16.8 years). Food intake, evaluated by number of consumed food portions, was below the recommendations for a normally active population in all food groups except animal proteins, where the intake was more than twice the recommended amount. In this population, with low BMI and intense exercise, BMC was low and associated with nutritional factors; dairy products had a positive and non-dairy proteins a negative influence. A positive correlation between BMAD and years since menarche confirmed the importance of exposure to estrogens and the negative impact of delayed puberty. Because of this and the probable negative influence of a high intake of non-dairy proteins, such as meat, fish, and eggs, and the positive association with a high dairy intake, ballet schools should promote balanced diets and normal weight and should recognize and help dancers avoid eating disorders and delayed puberty caused by extensive dancing and inadequate nutrition.

Bone microarchitecture assessed by TBS predicts osteoporotic fractures independent of bone density: The manitoba study.

The measurement of BMD by dual-energy X-ray absorptiometry (DXA) is the "gold standard" for diagnosing osteoporosis but does not directly reflect deterioration in bone microarchitecture. The trabecular bone score (TBS), a novel gray-level texture measurement that can be extracted from DXA images, correlates with 3D parameters of bone microarchitecture. Our aim was to evaluate the ability of lumbar spine TBS to predict future clinical osteoporotic fractures. A total of 29,407 women 50 years of age or older at the time of baseline hip and spine DXA were identified from a database containing all clinical results for the Province of Manitoba, Canada. Health service records were assessed for the incidence of nontraumatic osteoporotic fracture codes subsequent to BMD testing (mean follow-up 4.7 years). Lumbar spine TBS was derived for each spine DXA examination blinded to clinical parameters and outcomes. Osteoporotic fractures were identified in 1668 (5.7%) women, including 439 (1.5%) spine and 293 (1.0%) hip fractures. Significantly lower spine TBS and BMD were identified in women with major osteoporotic, spine, and hip fractures (all p < 0.0001). Spine TBS and BMD predicted fractures equally well, and the combination was superior to either measurement alone (p < 0.001). Spine TBS predicts osteoporotic fractures and provides information that is independent of spine and hip BMD. Combining the TBS trabecular texture index with BMD incrementally improves fracture prediction in postmenopausal women. © 2011 American Society for Bone and Mineral Research.