In this study a lumbar spinal fusion animal model is established to assess the effect of spinal fusion cage,and explore theminimum area ratio of titanium cage section to vertebral section that ensures bone healing and...In this study a lumbar spinal fusion animal model is established to assess the effect of spinal fusion cage,and explore theminimum area ratio of titanium cage section to vertebral section that ensures bone healing and biomechanical property.Lumbarcorpectomy was conducted by posterolateral approach with titanium cage implantation combined with plate fixation.Titaniumcages with the same length but different diameters were used.After implantation of titanium cages,the progress of bone healingwas observed and the bone biomechanical properties were measured,including deformation and displacement in axial compression,flexion,extension,and lateral bending motion.The factors affecting the in vivo growth of spine supporting body wereanalyzed.The results show that the area ratio of titanium cage section to vertebral section should reach 1/2 to ensure the bonehealing,sufficient bone intensity and biomechanical properties.Some bone healing indicators,such as BMP,suggest that there isa relationship between the peak time and the peak value of bone formation and metabolism markers and the bone healing strength.展开更多
To study the effect of titanium alloy cage on the treatment of the ischemic necrosis of femoral head in dog, the model of the ischemic necrosis of femoral head was made with the liquid nitrogen in 15 hybrid adult dogs...To study the effect of titanium alloy cage on the treatment of the ischemic necrosis of femoral head in dog, the model of the ischemic necrosis of femoral head was made with the liquid nitrogen in 15 hybrid adult dogs. The titanium alloy cage made of a hollow cylinder was driven into the subchondral bone of necrotic femoral head via central channel. The dogs were divided into 3 groups, each group was sacrificed 3, 6, 12 weeks after the operation respectively. No collapse of femoral head was observed after the operation. The position of the cages was good on radiograph. Microscopically, the cancellous bone of necrotic femoral head rebuilt gradually and grew into cage. After 12 weeks of creeping substitution, the cancellous bone filled up the hollow cavity and holes of the cages. It is concluded that the titanium alloy cage can provide structural support for the subchondral bone and prevent collapse and can be used for the treatment of the ischemic necrosis of femoral head.展开更多
Objective To compare the clinical effects of treating cervical prolapse of intervertebral disc by using Solis cage, titanium cage and autogenous iliac crest graft (AICG) combined with titanium plate. Methods 64 cases ...Objective To compare the clinical effects of treating cervical prolapse of intervertebral disc by using Solis cage, titanium cage and autogenous iliac crest graft (AICG) combined with titanium plate. Methods 64 cases of cervical prolapse of intervertebral disc were analyzed retrospectively. All the patients were followed up for about one year. Group A is composed of 20 patients (30 intervertebral spaces) treated with microdiscectomy and Solis cage fusion; group B is composed of 21 patients(22 intervertebral spaces) treated with titanium cage and group C is involved of 23 patients(28 intervertebral spaces) which were dealt with AICG combined with titanium plate. The differences in the total X ray exposure time, time working on iliac bone, incidence of complications, fusion rate, incidence of JOA score recovery rate more than 50% and rehabilitation time of the three groups are analyzed. Results All indexes from group A and B were more satisfactory than those from group C (P<0.05). The statistic analysis results of the incidence of complications of cervical part, rehabilitation time in group A are 5.0±1.8, 5.1±1.2; and that is 14.3±2.6, 7.5 ±1.6 and 26.1±6.2, 8.6±2.3 in group B and group C respectively. There is significant difference between group A and group B on the incidence of complications of cervical part and rehabilitation time (P<0.05). Results of the incidence of JOA score recovery rate >50% in group A(95.8±3.2) was more satisfactory than that in group B(93.6±2.9), while there was no statistical difference between group A and group B (P>0.05). Conclusion The Solis cage is better in treating the cervical prolapse of intervertebral disc than other ways. Also, it makes the operation easier, rehabilitation time shorter, and it causes fewer complications.展开更多
Few biomechanical data exist regarding whether the polyetheretherketone (PEEK) spacer or titanium spacer is better for posterior lumbar interbody fusion (PLIF). This study evaluated the biomechanical influence that th...Few biomechanical data exist regarding whether the polyetheretherketone (PEEK) spacer or titanium spacer is better for posterior lumbar interbody fusion (PLIF). This study evaluated the biomechanical influence that these types of spacers with different levels of hardness exert on the vertebra by using finite element analysis including bone strength distribution. To evaluate the risk of spacer subsidence for PLIF, we built a finite element model of the lumbar spine using computed tomography data of osteoporosis patients. Then, we simulated PLIF in L3/4 and built models with the hardness of the interbody spacer set as PEEK and titanium. Bones around the spacer were subjected to different load conditions. Then, fracture elements and some stress states of the two modalities were compared. In both models of PLIF simulation, fracture elements and stress were concentrated in the bones around the spacer. Fracture elements and stress values of the model simulating the PEEK spacer were significantly smaller compared to those of the titanium simulation model. For PLIF of osteoporotic vertebrae, this suggested that the PEEK spacer is in a mechanical environment less susceptible to subsidence caused by microfractures of bone tissue and bone remodeling-related fusion aspects. Therefore, PEEK spacers are bio-mechanically more useful.展开更多
This work focuses on the influence of elastic modulus on biomechanical properties of lumbar interbody fusion cages by selecting two titanium alloys with different elastic modulus. They were made by a new β type alloy...This work focuses on the influence of elastic modulus on biomechanical properties of lumbar interbody fusion cages by selecting two titanium alloys with different elastic modulus. They were made by a new β type alloy with chemical composition of Ti-24Nb-4Zr-7.6Sn having low Young＇s modulus -50 GPa and by a conventional biomedical alloy Ti-6Al-4V having Young＇s modulus -110 GPa. The results showed that the designed cages with low modulus （LMC） and high modulus （HMC） can keep identical compression load -9.8 kN and endure fatigue cycles higher than 5× 10^6 without functional or mechanical failure under 2.0 kN axial compression. The anti-subsidence ability of both group cages were examined by axial compression of thoracic spine specimens （T9-T10） dissected freshly from the calf with averaged age of 6 months. The results showed that the LMC has better anti-subsidence ability than the HMC （p〈0.05）. The above results suggest that the cage with low elastic modulus has great potential for clinical applications.展开更多
文摘In this study a lumbar spinal fusion animal model is established to assess the effect of spinal fusion cage,and explore theminimum area ratio of titanium cage section to vertebral section that ensures bone healing and biomechanical property.Lumbarcorpectomy was conducted by posterolateral approach with titanium cage implantation combined with plate fixation.Titaniumcages with the same length but different diameters were used.After implantation of titanium cages,the progress of bone healingwas observed and the bone biomechanical properties were measured,including deformation and displacement in axial compression,flexion,extension,and lateral bending motion.The factors affecting the in vivo growth of spine supporting body wereanalyzed.The results show that the area ratio of titanium cage section to vertebral section should reach 1/2 to ensure the bonehealing,sufficient bone intensity and biomechanical properties.Some bone healing indicators,such as BMP,suggest that there isa relationship between the peak time and the peak value of bone formation and metabolism markers and the bone healing strength.
基金a grant from the National Natural Sciences Foundation of China (No. 30170945)
文摘To study the effect of titanium alloy cage on the treatment of the ischemic necrosis of femoral head in dog, the model of the ischemic necrosis of femoral head was made with the liquid nitrogen in 15 hybrid adult dogs. The titanium alloy cage made of a hollow cylinder was driven into the subchondral bone of necrotic femoral head via central channel. The dogs were divided into 3 groups, each group was sacrificed 3, 6, 12 weeks after the operation respectively. No collapse of femoral head was observed after the operation. The position of the cages was good on radiograph. Microscopically, the cancellous bone of necrotic femoral head rebuilt gradually and grew into cage. After 12 weeks of creeping substitution, the cancellous bone filled up the hollow cavity and holes of the cages. It is concluded that the titanium alloy cage can provide structural support for the subchondral bone and prevent collapse and can be used for the treatment of the ischemic necrosis of femoral head.
文摘Objective To compare the clinical effects of treating cervical prolapse of intervertebral disc by using Solis cage, titanium cage and autogenous iliac crest graft (AICG) combined with titanium plate. Methods 64 cases of cervical prolapse of intervertebral disc were analyzed retrospectively. All the patients were followed up for about one year. Group A is composed of 20 patients (30 intervertebral spaces) treated with microdiscectomy and Solis cage fusion; group B is composed of 21 patients(22 intervertebral spaces) treated with titanium cage and group C is involved of 23 patients(28 intervertebral spaces) which were dealt with AICG combined with titanium plate. The differences in the total X ray exposure time, time working on iliac bone, incidence of complications, fusion rate, incidence of JOA score recovery rate more than 50% and rehabilitation time of the three groups are analyzed. Results All indexes from group A and B were more satisfactory than those from group C (P<0.05). The statistic analysis results of the incidence of complications of cervical part, rehabilitation time in group A are 5.0±1.8, 5.1±1.2; and that is 14.3±2.6, 7.5 ±1.6 and 26.1±6.2, 8.6±2.3 in group B and group C respectively. There is significant difference between group A and group B on the incidence of complications of cervical part and rehabilitation time (P<0.05). Results of the incidence of JOA score recovery rate >50% in group A(95.8±3.2) was more satisfactory than that in group B(93.6±2.9), while there was no statistical difference between group A and group B (P>0.05). Conclusion The Solis cage is better in treating the cervical prolapse of intervertebral disc than other ways. Also, it makes the operation easier, rehabilitation time shorter, and it causes fewer complications.
文摘Few biomechanical data exist regarding whether the polyetheretherketone (PEEK) spacer or titanium spacer is better for posterior lumbar interbody fusion (PLIF). This study evaluated the biomechanical influence that these types of spacers with different levels of hardness exert on the vertebra by using finite element analysis including bone strength distribution. To evaluate the risk of spacer subsidence for PLIF, we built a finite element model of the lumbar spine using computed tomography data of osteoporosis patients. Then, we simulated PLIF in L3/4 and built models with the hardness of the interbody spacer set as PEEK and titanium. Bones around the spacer were subjected to different load conditions. Then, fracture elements and some stress states of the two modalities were compared. In both models of PLIF simulation, fracture elements and stress were concentrated in the bones around the spacer. Fracture elements and stress values of the model simulating the PEEK spacer were significantly smaller compared to those of the titanium simulation model. For PLIF of osteoporotic vertebrae, this suggested that the PEEK spacer is in a mechanical environment less susceptible to subsidence caused by microfractures of bone tissue and bone remodeling-related fusion aspects. Therefore, PEEK spacers are bio-mechanically more useful.
文摘This work focuses on the influence of elastic modulus on biomechanical properties of lumbar interbody fusion cages by selecting two titanium alloys with different elastic modulus. They were made by a new β type alloy with chemical composition of Ti-24Nb-4Zr-7.6Sn having low Young＇s modulus -50 GPa and by a conventional biomedical alloy Ti-6Al-4V having Young＇s modulus -110 GPa. The results showed that the designed cages with low modulus （LMC） and high modulus （HMC） can keep identical compression load -9.8 kN and endure fatigue cycles higher than 5× 10^6 without functional or mechanical failure under 2.0 kN axial compression. The anti-subsidence ability of both group cages were examined by axial compression of thoracic spine specimens （T9-T10） dissected freshly from the calf with averaged age of 6 months. The results showed that the LMC has better anti-subsidence ability than the HMC （p〈0.05）. The above results suggest that the cage with low elastic modulus has great potential for clinical applications.
