[Low cement distribution index is a risk factor for refracture of the adjacent segments after percutaneous vertebroplasty].

OBJECTIVE: To investigate the impact of cement distribution index on the occurrence of refracture in the adjacent segments after percutaneous vertebroplasty. METHODS: This retrospective analysis was conducted among 143 patients who received percutaneous vertebroplasty for osteoporotic vertebral compression fracture between April, 2011 and April, 2014. Of the 134 patients with complete follow-up data, 18 had adjacent segment fracture within 1 year following the surgeries (re-fracture group), and 116 patients without new fracture served as the control group. All the patients underwent X-ray examinations after the surgery and according to the position and shape, the cement in the vertebrae were classified into 5 types (I to V), and the volume-cubage index was computed based on the cement volume and vertebral cubage. Age, gender, bone mineral density (BMD), cement distribution index, volume-cubage index, and cement leakage were evaluated in the 2 groups, and the variables with significant differences between the 2 groups were analyzed in Logistic regression analysis. RESULTS: BMD was significantly lower and the rate of cement leakage was significantly higher in the re-fracture group than in the control group (P<0.05). Significant difference was found in cement distribution index between the 2 groups (P<0.05) but not in age, gender, cement volume or volume-cubage index (P>0.05). Logistic regression analysis indicated that BMD, cement leakage and cement distribution index all significantly affected the occurrence of adjacent vertebral fractures following percutaneous vertebroplasty. CONCLUSION: A low BMD, cement leakage and a low cement distribution index are all risks factor of adjacent vertebral fracture after percutaneous vertebroplasty.

Expression of Fas receptor and apoptosis in vertebral endplates with degenerative disc diseases categorized as Modic type I or II.

STUDY DESIGN: Vertebral endplate tissues were obtained from patients with degenerated lumbar disc classified as Modic type 1 or type 2 and investigated with immunohistochemical staining and the DNA nick end labelling techniques. OBJECTIVE: To examine the expression of fas receptor (FasR) and apoptosis in the endplate cells isolated from patients with degenerative disc disease and to see whether they are associated with the pathological change of endplate. METHODS: Fifty-six degenerated lumbar endplate specimens were obtained from the patients with degenerative disc disease categorized as type Modic I or II in magnetic resonance imaging (MRI) and eight nondegenerated specimens as control (vertebra burst fracture patients without degenerative change in MRI) during surgical procedures. Immunohistochemical staining was performed to determine the presence of FasR and apoptosis in sections of those endplate tissues. To investigate whether the FasR expression and apoptosis in endplate were influenced by degeneration and ageing of the discs, the level of FasR expression and apoptosis in the changed and unchanged endplates was analysed. RESULTS: FasR were expressed in the cytoplasm of the endplate cells. A higher degree of FasR expression and apoptosis in endplate cells in degenerated discs was found than that in nondegenerated discs. In cell culture, the level of FasR expression and apoptosis in cells from the degenerative endplates was higher than those in unchanged endplates. The percentage of FasR-positive endplate and apoptotic endplate cells correlated significantly with the patient's age (r=0.301, p<0.05; r=0.307, p<0.05. respectively), but not with the degree of disc degeneration in MRI (r=0.047, p>0.05; r=0.066, p>0.05, respectively). CONCLUSION: This is the first study to compare the expression of FasR and apoptosis on vertebral endplate cells in degenerated disc with in nondegenerated disc. The results show that the endplate in degenerated disc may undergo fas-mediated apoptosis and vice versa, endplate degenerative changes may promotes apoptosis of the endplate cells within degenerated disc.

[Expressions of interleukin 18 and prostaglandin E2 and their correlation in the synoviocytes of patients with osteoarthritis].

OBJECTIVE: To explore the expression of interleukin 18 (IL-18) and prostaglandin E2 (PGE2) and their relationship in the synoviocytes of patients with osteoarthritis (OA). METHODS: The synovial tissues were obtained from 30 OA patients to isolate the synoviocytes for primary culture. The concentrations of IL-18 and PGE2 in the supernatants of synoviocyte culture were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: The concentration of IL-18 averaged 51.559-/+27.614 pg/ml and PGE2 327.036-/+333.561 pg/ml in the supernatant of the synoviocytes. A significant positive correlation was noted between their expressions (r=0.863, P<0.01). CONCLUSION: IL-18 may induce the production of PGE2, and their interactions they may play an important role in the pathogenesis of OA.

[Biological characteristics of human degenerative vertebral endplate cells].

OBJECTIVE: To observe the morphology and phenotypes of cells extracted from the endplate in the intervertebral discs and identify the factors affecting their biological characteristic. METHODS: The intervertebral disc endplate were digested enzymatically, and the morphology of the obtained cells was examined under light microscope. Immunhistochemical analysis of collagen II and real-time PCR was carried out, and the morphologies, viability, cell growth, apoptosis and chondrocyte matrix production were compared between the cells isolated from the degenerative and normal vertebral endplates. RESULTS: The cells in primary culture presented with spherical and oval morphology, and the cytoplasm was stained blue with toluidine blue. The morphologies of the cartilage endplate cells and the articular cells were almost identical. All the freshly isolated cells expressed collagen II. The degenerative vertebral endplate cells showed decreased expression of collagen II with increased apoptotic cells as compared with normal vertebral endplate cells. CONCLUSION: The intervertebral disc endplate cells, like articular cartilage cells, express cartilage-specific matrix proteins. Degenerative vertebral endplate cells show decreased cell vitality with increases cell apoptosis.