Objective To summarize the physicochemical properties, manufacturing technique, and biological characteristics of porous tantalum and its application progress and related problems in spinal surgery. Methods The domestic and foreign related literature about porous tantalum was summarized and analyzed. Results Porous tantalum is characterized by high porosity, high coefficient of friction, low elastic modulus, good biocompatibility, and superior osseointegration capability. Its manufacture methods include chemical vapor deposition and infiltration technique, foam impregnation and powder metallurgy technique, and heat treatment method. Good clinical efficacy has achieved in the application of porous tantalum interbody fusion Cage in cervical and lumbar fusion surgery, but there is controversy in spinal fusion rate, especially in cervical fusion rate. Surface modification can increase the osseointegration capability of porous tantalum and intervertebral bony fusion. Conclusion Good clinical efficacy has achieved in the application of porous tantalum interbody fusion Cage in lumbar fusion surgery, while there is a dispute in cervical fusion surgery. In order to further observation, studies with more patients and longer follow-up would be needed.
Graphene and its derivatives have good physical and chemical properties and biological properties, which can promote stem cell proliferation and osteogenic differentiation, and it has antibacterial properties and drug release property. Therefore, it has broad application prospects in the field of orthopedic biomaterials. This paper mainly introduces the research progress of graphene nanocomposite materials applied in the aspects of bone tissue engineering scaffold, bone repair, bone graft materials, etc. in order to provide desirable information for the future application basis and clinical research.
ObjectiveTo review the biological characteristics of self-assembling peptide nanofiber scaffold (SAPNS) and its potential to induce bone repair. MethodsThe literature regarding SAPNS and its application in bone repair was extensively analyzed and reviewed. ResultsSAPNS is derived from natural amino acids, and has the properties of good biocompatibility and non-toxic degradation products. Their microenvironment highly mimics the natural extracellular matrix, and controlled release of growth factors as well as modification with functional motifs can substantially improve their bioactivity. Many studies on cell composite culture and bone defect repair of animal models reveal that SAPNS has the ability to promote the function of bone cells (e.g. adherence, proliferation, and differentiation) in vitro, and enhance new bone tissue formation in vivo. ConclusionSAPNS may be an ideal material for bone repair, but its biologically mechanical properties need further improvement.
ObjectiveTo compare the biomechanical differences between the kidney-shaped nano-hydroxyapatite/polyamide 66 (n-HA/PA66) Cage and the bullet-shaped n-HA/PA66 Cage. MethodsL2-L5 spinal specimens were selected from 10 adult male pigs. L2, L3 and L4, L5 served as a motor unit respectively, 20 motor units altogether. They were divided into 4 groups (n=5):no treatment was given as control group (group A); nucleus pulposus resection was performed (group B); bullet-shaped Cage (group C), and kidney-shaped Cage (group D) were used in transforaminal lumbar interbody fusion (TLIF) through left intervertebral foramen and supplemented by posterior pedicle screw fixation. The intervertebral height (IH) and the position of Cages were observed on the X-ray films. The range of motion (ROM) was measured. ResultsThere was no significant difference in the preoperative IH among 4 groups (F=0.166, P=0.917). No significant change was found in IH between at pre- and post-operation in group B (P>0.05); it increased after operation in groups C and D, but difference was not statistically significant (P>0.05). There was no significant difference in the postoperative IH among groups B, C, and D (P>0.05). The distance from Cage to the left margin was (3.06±0.51) mm in group C (close to the left) and (5.68±0.69) mm in group D (close to the middle), showing significant difference (t=6.787, P=0.000). The ROM in all directions were significantly lower in groups C and D than in groups A and B (P<0.05), and in group A than in group B (P<0.05). The right bending and compression ROM of group C were significantly higher than those of group D (P<0.05), but no statistically significant difference was found in the other direction ROM (P>0.05). ConclusionThe bullet-shaped and kidney-shaped Cages have similar results in restoring IH and maintaining the stability of the spine assisted by internal fixation. Kidney-shaped Cage is more stable than bullet-shaped Cage in the axial compression and the bending load opposite implant, it can be placed in the middle and back of the vertebral body more ideally.
ObjectiveTo discuss the effect of glucosamine-hydrochloride (Glu/Ch) in protecting and repairing the cartilage in blood-induced joint damage (BJD) in vivo. MethodsThirty-two adult New Zealand rabbits were randomly divided into 4 groups (n=8):high-dose Glu/Ch treated group (group A), low-dose Glu/Ch treated group (group B), positive control group (group C), and negative control group (group D). A joint bleeding model was established by blood injection into articular cavity in groups A, B, and C. Glu/Ch was given by gavage in groups A (250 mg/kg) and B (21.5 mg/kg) once a day for 8 weeks, and the same dosage of saline was given in groups C and D. The serum cartilage oligomeric matrix protein (COMP), serum chondroitin sulfate 846(CS846), and urinary C-terminal telopepide of type II collagen (CTX-II) were measured at 3 days, 7 days, 2 weeks, and 8 weeks after modeling. The expressions of cytokines such as interleukin 1β (IL-1β) and tumor necrosis factor α (TNF-α) in synovial fluid were analyzed by ELISA at 8 weeks after modeling. The expression of matrix metalloproteinase 13(MMP-13) was detected by immunohistochemistry. Alcian blue staining and Safranin-O staining were performed to calculate the percentage of the positive staining areas. The proteoglycan content was detected by semi-quantitative analysis in the articular cartilage. ResultsThe COMP concentration was significantly higher in groups A, B, and C than group D, and in groups B and C than group A at 3 days after modeling (P<0.05); no significant difference was found among groups A, B, and D at 7 days (P>0.05), and it was significantly lower in groups A, B, and D than group C (P<0.05); there was no significant difference among 4 groups after 2 and 8 weeks (P>0.05). Difference in CS846 concentration had no significance among 4 groups at each time point (P>0.05). The CTX-II concentration of groups A, B, and C was significantly higher than that of group D at each time point (P<0.05); it was significantly lower in group A than groups B and C at 7 days, 2 weeks, and 8 weeks (P<0.05). The TNF-α concentration of groups A and B was significantly higher than group D, and was significantly lower than group C at 8 weeks (P<0.05), but no significant difference was observed between groups A and B (P>0.05). The IL-1β concentration was significantly higher in group C than the other groups (P<0.05), and in group B than groups A and D (P<0.05), but there was no significant difference between groups A and D (P>0.05). The MMP-13 expression was significantly higher in group C than groups A, B, and D (P<0.05), in groups A and B than group D (P<0.05). A significant decrease in the area stained with Alcian blue and Safranin-O was observed in group C. There were significant differences in the percentage of the positive stained areas of Alcian blue and Safranin-O among 4 groups (P<0.05). The relative quantities of proteoglycan from small to large in order was groups C, B, A, and D, respectively, showing significant differences (P<0.05). ConclusionThe metabolism disorder of cartilage matrix and synovium inflammatory reaction can be observed in rat joint bleeding model. Glu/Ch has certain protective effect on the cartilage after BJD by down-regulating IL-1β, TNF-α, and MMP-13, as well as increasing proteoglycan content in the cartilage.
The present study is aimed to investigate the early clinical effects of nano-hydroxyapatite/polyamide 66 intervertebral fusion cage (n-HA/PA66 cage) for the treatment of lumbar degenerative diseases. We selected 27 patients with lumbar degenerative diseases who were managed by posterior decompression or reset operation combined with n-HA/PA66 cage intervertebral fusion and internal fixation from August 2010 to January 2012. The oswestry disability index (ODI), low back and leg pain visual analogue score (VAS), and intervertebral height (IH) were evaluated at preoperation, 1 week postoperation and the last follow-up period, respectively. Intervertebral bony fusion was evaluated at the last follow-up time. The patients were followed up for 12-24 months (averaged 19 months). The ODI, VAS and IH were significantly improved at 1 week postoperation and the last follow-up time compared with those at preoperative period (P<0.05). But there was no significant difference between 1 week postoperative and the last follow-up time (P<0.05). Brantigan's standard was used to evaluate fusion at the last follow-up time. There were 19 patients with grade 5 fusion, 8 with grade 4 fusion, with a fusion rate of 100%, and none with grade 1-3 fusions. There was no cage translocation and internal fixation breakage. These results suggested that n-HA/PA66 cage was an ideal biological material in the posterior lumbar interbody fusion and internal fixation operation for treatment of lumbar degenerative diseases. It can effectively maintain the intervertebral height and keep a high rate of bony fusion. The early clinical effect has been satisfactory.
ObjectiveTo explore the effectiveness of posterior unilateral transpedicular debridement, bone graft fusion, and pedicle screw fixation for thoracolumbar tuberculosis. MethodsBetween January 2009 and January 2013, 97 patients with thoracolumbar tuberculosis were treated with posterior unilateral transpedicular debridement, bone graft fusion, and pedicle screw fixation in 53 cases (group A), and with traditional posterior operation in 44 cases (group B). There was no significant difference in age, sex, disease duration, affected segments, Frankel grade, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), sagittal Cobb angle, visual analogue scale (VAS), and Oswestry disability index (ODI) between 2 groups (P>0.05). The surgery and follow-up results were compared between 2 groups. ResultsThe patients were followed up 24-60 months. All patients achieved intervertebral bone fusion after operation. The bone graft fusion time of groups A and B was (6.79±1.68) months and (6.89±2.00) months respectively, showing no significant difference (t=-0.251, P=0.802). There was no significant difference in operation time, intraoperation blood loss, and postoperative hospitalization time between 2 groups (P>0.05); the postoperative drainage volume of group A was significantly less than that of group B (P<0.05). The CRP and ESR at 1 year and the VAS score at last follow-up were significantly decreased when compared with preoperative values in 2 groups (P<0.05), but no significant difference was found between 2 groups (P>0.05). The Cobb angle at 1 week and at last follow-up and ODI at 3 months and at last followup were significantly improved in 2 groups (P<0.05), but there was no significant difference between the time points after operation (P>0.05). At 3 months after operation, the ODI of group A was significantly lower than that of group B (t=-2.185, P=0.027), but no significant difference was found in Cobb angle, Cobb angle loss, and ODI at other time points between 2 groups (P>0.05). At last follow-up, the Frankel classification of nerve function was improved 1-2 grades in 2 groups, showing no significant difference between 2 groups (Z=-0.180, P=0.857). No complication of internal fixation breakage or loosening was observed. ConclusionThe effectiveness of posterior unilateral transpedicular debridement, bone graft fusion, and pedicle screw fixation in the treatment of thoracolumbar tuberculosis is satisfactory, with the advantages of less trauma, strong spinal stability, and fast function recovery.