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Background Aims: Advances in bone tissue engineering with mesenchymal stromal cells (MSC) as an alternative to conventional orthopedic procedures has opened new horizons for the treatment of large bone defects. Bone marrow (BM) and trabecular bone are both sources of MSC. Regarding clinical use, we tested the potency of MSC from different sources., Methods: We obtained MSC from 17 donors (mean age 64.6 years) by extensive washing of trabecular bone from the femoral head and trochanter, as well as BM aspirates of the iliac crest and trochanter. The starting material was evaluated by histologic analysis and assessment of colony-forming unit-fibroblasts (CFU-F). The MSC populations were compared for proliferation and differentiation potential, at RNA and morphologic levels., Results: MSC proliferation potential and immunophenotype (expression of CD49a, CD73, CD90, CD105, CD146 and Stro-1) were similar whatever the starting material. However, the differentiation potential of MSC obtained by bone washing was impaired compared with aspiration; culture-amplified cells showed few Oil Red O-positive adipocytes and few mineralized areas and formed inconsistent Alcian blue-positive high-density micropellets after growth under adipogenic, osteogenic and chondrogenic conditions, respectively. MSC cultured with 1 ng/mL fibroblast growth factor 2 (FGF-2) showed better differentiation potential., Conclusions: Trabecular bone MSC from elderly patients is not good starting material for use in cell therapy for bone repair and regeneration, unless cultured in the presence of FGF-2.

Thoracolumbar fractures are frequent and the functional outcomes are sometimes severe. This multicentric study, including five medical centers, was performed to evaluate the long-term outcomes of the patients. One hundred and thirty six patients with thoracolumbar fracture (T11 to L2) was evaluated with a minimal follow-up of two years. Every one had a clinical exam with a score of Oswestry and an X-Ray study (before and after treatment and at revision). Most of them presented compression fractures, the most often at L1 level. On X-rays, a gain was noted on the vertebral kyphosis immediately after surgery, but there is a loss of correction over time whatever the treatment. The clinical outcomes for the patients were great, with an Oswestry average score of 6,4. A correlation was noted between this functional score and vertebral kyphosis. So, an anterior column strengthening (isolated or performed during the surgery) could improve these functional outcomes. Moreover, the Thoraco Lumbar Injury Severity Score (TLISS) seems to be a simple organigram to determine the most appropriate treatment of these fractures, with particular attention to the distraction mechanism or posterior ligamentous complex lesions. However, RMI before surgery is necessary to evaluate these lesions.

The tibial valgus osteotomy whatever its technique has a survival rate of about 85 % to 10 years, if we consider the reoperation as a criterion of failure, with a confidence index at 78%. The age, weight, sex and functional signs have no impact on the outcome. We have found no evidence in the preoperative radiographic assessment, neither the medial pinch, or varus epiphyseal neither varisant gap, which could be a failure and a reoperation before the tenth year. Good results were observed significantly when there is an over-valgus at least 3 degrees of global axis of the lower limb. This corresponds to a valgus epiphyseal by more than 2 degrees . The substantial reduction in the gap varisant that lowers the overall time varisant below 200 kg cm provides the same positive results. The outcome will depend directly on the accuracy of the calculation of the preoperative correction performed and the quality of surgical achievement. Because of the need for precision, navigation technique appears as reliable, simple which makes it also possible to monitor the front slope and tibial rotation induced. The osteosynthesis must be stable and rigid to avoid postoperative loss of correction.

The aim of this study was to assess the frequency of gastrointestinal side effects (GSE) and hepatotoxicity in patients treated with rifampicin for an osteoarticular infection and to determine if there is an association between rifampicin plasma concentrations and side effects. Rifampicin plasma concentrations were prospectively measured before (trough concentration, C(0)) and 2 +/- 0.5 h (peak concentration, C(2)) after drug intake. The presence of GSE, the alanine transferase (ALT) value, and concomitantly administered medications were recorded on the day rifampicin concentrations were measured. C(0) and C(2) were compared for differences regarding the presence or absence of side effects. Multivariate analysis was performed, with associated medications being taken into account. Seventy C(0) and 57 C(2) values were measured in 46 adults after a median treatment of 8 days (range, 1-179). Wide inter-individual variability was observed for C(0) and C(2). Thirteen (28%) patients reported GSE at least once. When GSE occurred, C(0) (median, 1 mg L(-1); range, 0.1-9.9 mg L(-1)) and C(2) (median, 10.3 mg L(-1); range, 1.8-40.3 mg L(-1)) were similar to C(0) (median, 0.6 mg L(-1); range, 0.1-10.3 mg L(-1)) and C(2) (median, 10.9 mg L(-1); range, 2.9-29.0 mg L(-1)) without GSE. The ALT value was more than normal in only three patients (6.5%) after rifampicin treatment began. The patients received no different associated medications whether or not GSE were present. Multivariate analysis showed no association between rifampicin plasma concentrations and GSE. GSE occur frequently in patients receiving rifampicin for osteoarticular infection but without an association with rifampicin plasma concentrations. Thus, therapeutic drug monitoring of rifampicin is irrelevant in the management of GSE.

Mesenchymal stem cells (MSC) are progenitors of osteoblasts, chondrocytes and adipocytes. They are in the bone marrow at the concentration of 1 to 104 at 105 mononucleated cells. There is not specific marker to select them. They can be cultured and differentiated in osteoblats or chondrocytes. They induced osteoformation in autologous bone graft. Therapeutic application includes concentrate of bone marrow or MSC expanded by culture, implanted with or without biomaterials. The implantation of MSC cultured on biomaterial has not been yet published in human. The aim of these technics is to reduce the use of bone graft. The first indications for these technics will be pseudarthrosis and bone defect.

The first step for treatment of bone metastases is to confirm the diagnosis, particularly if there is only one localisation, so as to exclude a primary bone tumour. Surgery and percutaneous injection of acrylic cement are both efficient to relieve pain. Their indications and timing have to be discussed in pluridisciplinary staff. Long bones metastases have to be nailed before pathologic fracture. If there is suspicion of hypervascularisation, the lesion has to be embolized before any procedure. Treatment of spinal metastases with neurological impairment is an emergency. Paraplegia may be a consequence within a few hours. They have to be treated in an orthopedic or neurosurgery department with the experience of posterior and anterior approach of the spine. Surveillance may be useful to diagnose these metastases before neurological impairment. Depending from the type of cancer, the chemo- and radiotherapy sensibility, the number of metastases, the condition of the posterior wall of the vertebra and the general condition of the patient, different surgical treatments may be possible going from complete resection of the lesion to percutaneous injection of acrylic cement. Conventional radiotherapy is associated to surgery. Satisfactory results of such treatments justify greater involvement of orthopaedic surgery team in multidisciplinary staff.

Pathological osteolyses are considered a consequence of a disturbance in the mechanisms that govern the bone remodeling, mainly the communication between osteoclasts and osteoblasts. Osteoprotegerin (OPG) and receptor activator of NF-kappaB ligand (RANKL) are newly discovered molecules that play a key role in these communications. RANKL is essential for osteoclast differentiation via its receptor RANK located on the osteoclast membrane. OPG is a soluble decoy receptor that inhibits osteoclast differentiation through its binding to RANKL. The aim of this study is the analysis of the RANKL/OPG balance by complementary methods (semiquantitative reverse transcription-polymerase chain reaction, immunohistochemistry, and enzyme-linked immunosorbent assay) in human osteolysis associated to various bone etiologies (n = 60), tumoral (primitive, secondary) or not, compared to healthy tissues (n = 16). Results demonstrated that RANKL/OPG ratio was significantly increased in patients suffering from severe osteolysis compared to the control group and that this imbalance is involved in bone resorption mechanisms. In this study, OPG expression appears to reflect a protective mechanism of the skeleton to compensate increased bone resorption by inhibiting osteoclast formation and bone resorbing activity. Moreover, as revealed by immunohistochemistry, RANKL and OPG were colocalized in all of the tissues analyzed. To define the veracity of RANKL/OPG index in assessing and managing patients with severe osteolysis, an extended population of patients suffering from severe osteolysis must be now monitored.

We present a comparative study of measurement of dog-epithelium-specific IgE by two Pharmacia CAP Rast techniques e2 and e5. For both measurements the technique is identical, but the allergen extracts are different: e2 = dachshund extract whilst e5 = a mixture of squames of german shepherd and poodle. We show that the e5-specific IgE seems to be more sensitive than the e2-specific IgE.