Vertebroplasty versus kyphoplasty in osteoporotic vertebral compression fracture: a meta-analysis of prospective comparative studies.

PURPOSE: The goal of this article is to evaluate the efficacy and the safety of the percutaneous vertebroplasty (PVP) versus percutaneous kyphoplasty (PKP) in dealing with the osteoporotic vertebral compression fracture (OVCF). METHODS: In July 2014, a comprehensive systematic computer-based online search was performed by using the databases of PubMed, EMBASE, Cochrane Library, Web of Science, Wan Fang, and the China Biological Medicine. Only prospective comparative trials (PCT) and randomized controlled trials (RCT) that compared PVP with PKP were included. Trials were screened based on the inclusion and exclusion criteria previously formed. The Cochrane collaboration guidelines were also used to assess the quality of these included studies. The primary data of these studies [volume of the cement, postoperative vertebral height, visual analog scale (VAS) score and Oswestry Disability Index (ODI) score after the surgery, and so on] were carefully abstracted and processed by Revman 5.2.0 software The publication bias of the main results (cement leakage and adjacent-level fracture) were examined by Stata 12.0 (Begg and Egger test). Furthermore, the stability of the main results were also detected by sensitivity and cumulative analyses. RESULTS: Six RCT and 14 PCT studies involving 1,429 patients met our criteria and were included finally. Comparing these two methods, the PKP group took more operation time [SMD = 0.66, 95 % CI (0.28, 1.03), p = 0.0006] with higher anterior vertebral body height [SMD = 1.40, 95 % CI (0.49, 2.32), p = 0.003], greatly reduced Cobb angle in the long run [SMD = -0.61, 95 % CI (-1.04, -0.19), p = 0.005] and had lower risk of cement leakage. However, in VAS scores and ODI scores after the surgery whether for the short-term efficacy (no more than 1 week after the surgery) or long-term efficacy (more than six months), Cobb angle in the short run and new fracture in the adjacent level, no statistically differences were found between the two groups. CONCLUSIONS: Based on current evidence, PVP takes less time in the operation, while it has greater risk of cement leakage, was inferior in reducing Cobb angle in the long term and results in lower anterior vertebral body height after the surgery. For pain relief, which is the main desire of the patients, both procedures provide significant improvement in VAS and ODI pain scores. PVP is still an effective procedure.

Construction of collagen II/hyaluronate/chondroitin-6-sulfate tri-copolymer scaffold for nucleus pulposus tissue engineering and preliminary analysis of its physico-chemical properties and biocompatibility.

To construct a novel scaffold for nucleus pulposus (NP) tissue engineering, The porous type II collagen (CII)/hyaluronate (HyA)-chondroitin-6-sulfate (6-CS) scaffold was prepared using 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC) and N-hydroxysuccinimide (NHS) cross-linking system. The physico-chemical properties and biocompatibility of CII/HyA-CS scaffolds were evaluated. The results suggested CII/HyA-CS scaffolds have a highly porous structure (porosity: 94.8 +/- 1.5%), high water-binding capacity (79.2 +/- 2.8%) and significantly improved mechanical stability by EDC/NHS crosslinking (denaturation temperature: 74.6 +/- 1.8 and 58.1 +/- 2.6 degrees C, respectively, for the crosslinked scaffolds and the non-crosslinked; collagenase degradation rate: 39.5 +/- 3.4 and 63.5 +/- 2.0%, respectively, for the crosslinked scaffolds and the non-crosslinked). The CII/HyA-CS scaffolds also showed satisfactory cytocompatibility and histocompatibility as well as low immunogenicity. These results indicate CII/HyA-CS scaffolds may be an alternative material for NP tissue engineering due to the similarity of its composition and physico-chemical properties to those of the extracellular matrices (ECM) of native NP.

Anti-HBV effect of liposome-encapsulated matrine in vitro and in vivo.

AIM: To study the anti-HBV effect of liposome-encapsulated matrine (Lip-M) in vitro and in vivo. METHODS: 2.2.15 cell line was cultured in vitro to observe the effect of Lip-M and matrine on the secretion of HBsAg and HBeAg. The toxicity of Lip-M and matrine to 2.2.15 cell line was also studied by MTT method. In in vivo study, drug treatment experiment was carried out on the 13th day after ducks were infected with duck hepatitis B virus (DHBV). The ducks were randomly divided into 4 groups with 5-6 ducks in each group. Lip-M and matrine were given to DHBV-infected ducks respectively by gastric perfusion. Four groups were observed: group of Lip-M (20 mg/kg), group of Lip-M (10 mg/kg), group of matrine (20 mg/kg) and group of blank model. The drug was given once daily for 20 d continuously, and normal saline was used as control. The blood was drawn from the posterior tibial vein of all ducks before treatment (T(0)), after the medication for 5 (T5), 10 (T10), 15 (T15), 20 (T20) d and withdrawl of the drug for 3 d (P3). The serum samples were separated and stored at -70 degrees, DHBV-DNA was detected by the dot-blot hybridization. RESULTS: After addition of Lip-M and matrine to 2.2.15 cell line for eleven d, the median toxic concentration (TC50) of Lip-M and matrine was 7.29 mg/mL and 1.33 mg/mL respectively. The median concentration (IC50) of Lip-M to inhibit HBsAg and HBeAg expression was 0.078 mg/mL and 3.35 mg/mL respectively. The treatment index (TI) value of Lip-M for HBsAg and HBeAg was 93.46 and 2.17 respectively, better than that of matrine. The DHBV-infected duck model treatment test showed that the duck serum DHBV-DNA levels were markedly reduced in the group of Lip-M (20 mg/kg) after treated by gastric perfusion for 10, 15 and 20 d (0.43+/-0.22 vs 0.95+/-0.18, t = 4.70, P = 0.001<0.01.0.40+/-0.12 vs 0.95+/-0.18, t = 6.34, P = 0.000<0.01. 0.22+/-0.10 vs 0.95+/-0.18, t = 8.30, P = 0.000<0.01), compared to the group of matrine (20 mg/kg) (0.43+/-0.22 vs 0.79+/-0.19, t = 3.17, P = 0.01<0.05. 0.40+/-0.12 vs 0.73+/-0.24, t = 3.21, P = 0.009<0.05. 0.22+/-0.10 vs 0.55+/-0.32, t = 2.27, P = 0.046<0.05.), and the control(0.43+/-0.22 vs 0.98+/-0.29, t = 3.68, P = 0.005<0.01. 0.40+/-0.12 vs 0.97+/-0.30, t = 4.26, P = 0.002<0.01. 0.22+/-0.10 vs 0.95+/-0.27, t = 5.76, P = 0.000<0.01). After the treatment for 20 d and withdrawl of the drug for 3 d, duck serum DHBV-DNA level in the group of Lip-M (10 mg/kg) markedly reduced (0.56+/-0.26 vs 0.95+/-0.38, t = 5.26, P = 0.003<0.05. 0.55+/-0.25 vs 0.95+/-0.38, t = 5.52, P = 0.003<0.05), and the difference was significant as compared with the control (0.56+/-0.26 vs 0.95+/-0.27, t = 2.37, P = 0.042<0.05. 0.55+/-0.25 vs 0.89+/-0.18, t = 2.55, P = 0.031<0.05), but not significant as compared with the group of matrine (20 mg/kg). After withdrawl of the drug for 3 d, the levels of DHBV-DNA did not relapse in both groups of Lip-M. CONCLUSION: Lip-M can evidently inhibit the replication of hepatitis B virus in vitro and in vivo; its anti-HBV effect is better than that of matrine.

Regeneration of the intervertebral disc with nucleus pulposus cell-seeded collagen II/hyaluronan/chondroitin-6-sulfate tri-copolymer constructs in a rabbit disc degeneration model.

STUDY DESIGN: Advancement in tissue engineering provides a promising approach to recover the functionality of the degenerated intervertebral disc. In our study, a nucleus pulposus (NP) cell-seeded collagen II/hyaluronan/chondroitin-6-sulfate (CII/HyA/CS) tri-copolymer construct was implanted into the disc space directly after nucleotomy in a rabbit model. OBJECTIVE: The aim of this study was to investigate whether the NP cell-seeded CII/HyA/CS tri-copolymer constructs could regenerate the degenerated disc in vivo after implantation into the rabbit nucleotomy model. SUMMARY OF BACKGROUND DATA: Nucleotomy is one of the most prevalent surgical modalities to treat degenerative disc disease, which could achieve good short-term effects of pain relieve, whereas removal of the entire or partial NP changes the biomechanical characteristics of the remaining disc and the adjacent vertebral segments and a series of long-term complications such as accelerated annulus and the facet joints degeneration may ensue. Therefore, it is necessary to think about possible procedures immediately after the primary nucleotomy surgery to avoid these complications. METHODS: NP cells isolated from thoracic and lumbar spines of New Zealand White rabbits of approximately 3 weeks of age and 1 kg in weight were labeled with a 5- (and-6) -carboxyflurescein diacetate succinimidyl ester (CFDA-SE) fluorescent dye and seeded within the CII/HyA/CS scaffold by a centrifugation method. After in vitro culture for 1 week, NP cell-seeded CII/HyA/CS tri-copolymer constructs were allografted into the disc defects of recipient rabbit immediately after nucleotomy of the lumbar spine. The Bradner Disc Index and the T2-weighted signal intensity index were determined using lateral plane radiographs and magnetic resonance imaging at 4, 12, and 24 weeks after the operation. Finally, the operated discs were explanted for gross morphological observation, histological evaluation, and cell viability assessment. Animals with only nucleotomy and cell-free CII/HyA/CS scaffold implantation served as controls. RESULTS: In our study, we could demonstrate that the T2-weighted signal intensity index of the operated discs decreased in all three groups 1 month after surgery and the index of the cell-containing scaffold insertion group was significantly higher than that of the other two groups. After 24 weeks, the index of the cell-containing scaffold insertion group increased significantly. However, further decline was observed in both the noninsertion group and the scaffold insertion group. In radiographic analysis, the narrowing of the intervertebral disc space was significantly retarded by the cell-scaffold hybrids implantation up to 24 postoperative weeks. Furthermore, the gross morphology and histological evaluation indicated that the allografted NP cells were viable and showed extracellular matrix production. CONCLUSION: In our study, we had constructed rabbit NP cell-seeded CII/HyA/CS tri-copolymer implants in vitro. Immediately after nucleotomy of the recipient rabbit, we allografted the precultured cell-scaffold hybrids into the lacuna of the disc. Results documented survival of the allografted NP cells and extracellular matrix deposition, which finally resulted in maintenance of disc height and restoration of T2-weighted signal intensity on magnetic resonance imaging.

Comparison of percutaneous and open anterior screw fixation in the treatment of type II and rostral type III odontoid fractures.

STUDY DESIGN: Prospective controlled study of the clinical and radiographic results of a group of 42 cases having undergone anterior screw fixation for type II and rostal type III odontoid fractures. OBJECTIVE: The objective of this study is to determine the safety and efficacy of percutaneous anterior screw fixation as an alternative new technique in the management of type II and rostal type III odontoid fractures. SUMMARY OF BACKGROUND DATA: Minimally invasive spinal techniques have only recently been developed. However, clinical and radiographic outcome of minimally invasive anterior screw fixation for odontoid fractures has been evaluated in very few studies. There have been no prospective clinical reports published on the comparison of percutaneous anterior screw fixation for type II and "shallow" type III odontoid fractures or a traditional open manner. METHODS: Forty-two patients, 26 men and 16 women, with an average age of 47.1 years (32-65) were prospectively evaluated. All patients underwent percutaneous anterior screw fixation(n = 19) or open screw fixation (n = 23). The following data were compared between the two groups: operative time, blood loss, radiograph exposure time, the clinical and radiographic results, and complications. Radiologic examination of the cervical spine with plain radiographs was performed at 3, 6, and 12 months after surgery. RESULTS: In comparison with open fixation group, percutaneous fixation group had significantly less operating time and less blood loss. The radiation time and clinical outcome were basically identical in two groups. Radiographic evaluation showed satisfactory bony union and no evidence of abnormal movement at the fracture site in both percutaneous fixation group (18 of 19 cases) and open fixation group (22 of 23 cases). Two cases of postoperative dysphagia occurred in open screw fixation group. CONCLUSION: Percutaneous anterior screw fixation is a safe and reliable procedure for treatment of type II and rostral type III odontoid fractures with potential advantages.

Collagen II/hyaluronan/chondroitin-6-sulfate tri-copolymer scaffold for nucleus pulposus tissue engineering.

This study aims to investigate the bioactivity of collagen II/hyaluronan/chondroitin-6-sulfate tri-copolymer as bionic scaffold for nucleus pulposus (NP) tissue engineering. Collagen II (C II) (pH 1-2) was mixed with hyaluronan (HyA) and lyophilized to prepare C II/HyA matrices. Chondroitin 6-sulfate (6-CS) was covalently attached to the C II/HyA matrices using 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide (NHS). Then, cells were expanded from rabbit NP and seeded in the tri-copolymer scaffold. Cell-scaffold hybrids were maintained for up to 28 days in culture. Cell viability/proliferation, extracellular matrix (ECM)-related gene expression, and the content of sulfated glycosaminoglycans (s-GAG) were evaluated. Our results are as following: when cultured for 28 days, the cell-scaffold hybrids maintained active cell viability/proliferation and exhibited a significantly increased s-GAG content. In addition, rabbit NP cells cultured in the scaffold demonstrated a significantly higher level of C II and aggrecan gene expression and a significantly lower level of Collagen I (C I) gene expression when compared with that of monolayer cells. Histological studies and scanning electron microscopy (SEM) further indicated newly secreted ECM deposits in the scaffolds. In conclusion, the C II/HyA-CS scaffold may be an alternative material for NP tissue engineering due to its satisfactory bioactivity, and it deserves further in vivo investigation.