[Development and in vivo biomechanics of goat mobile artificial lumbar spine complex].

OBJECTIVE: Mobile artificial lumbar complex (MALC) which suitable for reconstruction after subtotal lumbar resection in goats was developed,and to test stability of the complex and postoperative lumbar segmental motor function. METHODS: Eighteen male boer goats aged from 1 to 2 years old (weighted from 35 to 45 kg) were selected and divided into control group,fusion group and non-fusion group,with 6 goats in each group. According to preoperative CT scans and MRI examinations of lumbar,the goat MALC was designed and performed by 3D printed for non-fusion group. Operation was performed on three groups respectively,and only vertebral body and disc were exposed in control group. In fusion group,L4 part of vertebral body and the upper and lower complete disc tissues were removed,and the lumbar spine bone plate fixation was performed with titanium mesh bone grafting. In non-fusion group,vertebral body and disc were removed in the same way,and MALC was implanted. AP and lateral X-rays of lumbar vertebrae in goat were taken at 6 months after surgery,in order to understand whether the plant was dislocated,displaced and fractured. Biomechanical tests were performed on the specimens by mechanical instrument to measure range of motion (ROM) of L2,3,L3,4,L4,5 intervertebral space and the overall ROM of L2-5 lumbar vertebrae. RESULTS: MALC of lumbar vertebra was designed by 3D printing,and its component artificial vertebrae and upper and lower artificial end plates were manufactured. The semi-spherical structure was fabricated by precision lathe using high-crosslinked polyethylene material,and the prosthesis was assembled. Postoperative AP and lateral X-rays of lumbar vertebra at 6 months showed the implant position of implant and MALC were good without displacement and dislocation. In vitro biomechanical test of lumbar vertebrae specimens:(1) There were no statistical significance in ROM of lumbar intervertebral space flexion and extension,lateral flexion and rotation on L3,4 and L4,5,between non-fusion group and control group (P>0.05),while ROM of fusion group was significantly reduced compared with the other two groups (P<0.05). There were no significant difference in ROM of L2,3 intervertebral flexion and extension,lateral flexion and rotation between non-fusion group and control group (P>0.05),while fusion group was significantly increased compared with the other two groups (P<0.001). (2) There was no significant difference in overall lumbar ROM of L2-5 (P> 0.05). CONCLUSION: The individual MALC could restore intervertebral height of lumbar vertebra while maintaining the stability of lumbar vertebra and re-establishing motor function of lumbar space.

Associations between D3R expression in synovial mast cells and disease activity and oxidant status in patients with rheumatoid arthritis.

Dopamine D3 receptor (D3R) on immune cells is involved in the pathogenesis of rheumatoid arthritis (RA). Mast cells (MCs) are currently identified as important effector cells in synovial inflammation of RA, but little is known about the role of D3R on synovial MCs in the pathogenesis of RA. Several inflammatory cells in the synovium induce reactive oxygen species (ROS) formation which are involved in the progression of RA. However, it is unclear whether D3R on synovial MCs is related to the levels of ROS in RA patients. In this study, a total of 73 patients with RA were divided into three groups according to disease activity DAS28 scores. The number of cases in group 1, group 2, and group 3 was 19, 26, and 28, respectively. We examined D3R-positive MC numbers in the synovial fluid and ROS levels in each group of RA patients, and we also analyzed the association of D3R-positive MC numbers with RA disease activity and ROS levels. MDA and protein carbonylation in the serum and synovial fluid were measured to reflect the level of lipid peroxidation and protein oxidation, respectively. Additionally, superoxide dismutase (SOD) and catalase (CAT) in the serum and synovial fluid were used to be markers of antioxidant levels. Our results showed that D3R-positive MCs in the synovial fluid showed a declining trend with the increased disease activity DAS28 score in RA patients. There was negative correlation between D3R-positive MC numbers in the synovial fluid and disease severity DAS28 score of RA patients. Moreover, D3R-positive MC numbers in the synovial fluid were negatively correlated with the level of MDA and protein carbonylation while were positively correlated with antioxidant levels such as SOD and CAT in RA patients. Our results suggested that D3R on MCs may be involved in ROS-mediated pathogenesis of RA.

Image-guided minimally invasive percutaneous treatment of spinal metastasis.

In order to provide effective options for minimally invasive treatment of spinal metastases, the present study retrospectively evaluated the efficacy and safety of image-guided minimally invasive percutaneous treatment of spinal metastases. Image-guided percutaneous vertebral body enhancement, radiofrequency ablation (RFA) and tumor debulking combined with other methods to strengthen the vertebrae were applied dependent on the indications. Percutaneous vertebroplasty (PVP) was used when vertebral body destruction was simple. In addition, RFA was used in cases where pure spinal epidural soft tissue mass or accessories (spinous process, vertebral plate and vertebral pedicle) were destroyed, but vertebral integrity and stability existed. Tumor debulking (also known as limited RFA) combined with vertebral augmentation were used in cases presenting destruction of the epidural soft tissue mass and accessories, and pathological vertebral fractures. A comprehensive assessment was performed through a standardized questionnaire and indicators including biomechanical stability of the spine, quality of life, neurological status and tumor progression status were assessed during the 6 weeks-6 months follow-up following surgery. After the most suitable treatment was used, the biomechanical stability of the spine was increased, the pain caused by spinal metastases within 6 weeks was significantly reduced, while the daily activities and quality of life were improved. The mean progression-free survival of tumors was 330±54 days, and no associated complications occurred. Therefore, the use of a combination of image-guided PVP, RFA and other methods is safe and effective for the treatment of spinal metastases.

[Impact of anterior cervical fusion surgeries on adjacent segments: a finite element analysis].

OBJECTIVE: To investigate the changes in the range of motion (ROM) and stress of the intervertebral disc and facet joint of the adjacent segments following anterior cervical corpectomy and fusion (ACCF) and anterior cervical discectomy and fusion (ACDF) using finite element analysis. METHODS: A three-dimensional finite element model of the lower cervical vertebrae was constructed and validated by comparing the ROM of the finite element model against the published data. After the validation of successful modeling, finite element models of ACDF and ACCF were constructed. The ROM and the stress of the intervertebral disc and facet joint of the adjacent segments were compared between the intact lower cervical vertebrae and the cervical vertebrae after ACDF and ACCF. RESULTS: The ROM of the finite element model was consistent with the published data. The total ROM and the ROM of the fusion segments with ACDF and ACCF were significantly decreased compared with the intact cervical vertebrae. In the adjacent segments following ACDF and ACCF, the ROM the adjacent segments and the stress peak of the intervertebral disc and facet joint all increased obviously compared with those of intact cervical vertebrae. CONCLUSION: After fusion surgeries, the total ROM of the cervical vertebrae decreases and the ROM of the adjacent segment increases. The stress peak of the intervertebral disc and facet joint of the adjacent segments also increases to significantly alter the physiological characteristics of the intact cervical vertebrae.

[Clinical observation on the treatment of atlantoaxial dislocation based on the classification].

OBJECTIVE: To retrospectively analyze the surgical methods and its clinical effects and explore a clinical classification and treatment strategy for atlantoaxial dislocation(AAD). METHODS: The clinical data of 89 patients with atlantoaxial dislocation were analyzed from September 2005 to September 2013. There were 49 males and 40 females, aged from 13 to 67 years with an average of 48.1 years. According to the reductive effects with preoperative cervical dynamic radiograph and high weight skeletal traction under general anesthesia, the dislocations were classified into three types:easy reduction type, hard reduction type and irreducible type. The patients with easy reduction type were treated with posterior screw rod internal fixation after manual reduction, while the patients with hard reduction type were treated with posterior screw rod fixation after high weight skeletal traction reduction under general anesthesia. The patients with irreducible type were treated with transoral atlantoaxial joint release or depression and posterior internal fixation and fusion. According to JOA scores to evaluate the neurological status and treatment outcome. RESULTS: Thirty patients were classified as easy reduction type, 55 patients as hard reduction type, and 4 patients as irreducible type. The preoperative JOA score was 8.2±3.1 on average, while the postoperative score was 14.2±2.4. The improvement rate was 40.1% to 82.5% with an average of 62.5%. Eighty nine patients were followed up from 6 to 37 months with a mean of 17.3 months. Eighty two cases obtained anatomical reduction and 85 cases obtained bony fusion. One case complicated with hyponatremia after operation and 1 case combined with Guillain-Barre syndrome, 4 cases complicated with delayed union wounds, 1 case died of for respiratory failure 2 years after operation. No wound infections were found in the patients approach for transoral operation. CONCLUSIONS: According to the cervical dynamic radiograph and high weight skeletal traction under general anesthesia to classify for atlantoaxial dislocation, and adopting well strategies to treat the patients, can achieve satisfactory effects.

[Clinical application of continuous douche and vacuum sealing drainage in refractory tissue, bone and joint infections after debridement].

OBJECTIVE: To explore effect and the application value of continuous douche and vacuum sealing drainage (VSD) in refractory tissue, and joint infections after complete debridement. METHODS: As retrospective analysis of treatment time and restoration or recurrence, from Jan. 2006 to Dec. 2007, 61 cases of refractory tissue, bone and joint infections underwent continuous douche and VSD combined with the treatment of anti-inflammatory and rehabilitation training after debridement in our hospital. The 61 patients included 39 males and 22 females with age ranging from 10 to 58 years with an average of (35 +/- 12) years, among whom 61 identified to have ankle ulcers combined with infections,open fracture combined with infections, sacrococcygeal pressure ulcers combined with infections, infections after hip replacement, infections after open fracture, and infections after skin avulsion postoperation were 11, 15, 9, 3, 5 and 18 cases respectively. The course was from 2 weeks to 11 months with an average of 4 months. RESULTS: In all 61 patients,the mean healing time was 17, 36, 42, 24, 32, 29 and 28 days in ankle ulcers and infections, tibia and fibula open fracture and infections, femoral shaft fracture and infections, sacrococcygeal pressure ulcers and infections, infections after hip replacement, infections after open fracture, and infections after skin avulsion postoperation respectively. The replacement of VSD was 1, 2-4, 3-5, 1-3, 2-4, 2-3 and 1-3 times in each group respectively. There was no wound recurrence except for 2 cases with recurrent in 61 cases with external fixation nail hole semi-pathological fracture in 1 case of femoral shaft fracture and infection and 1 case of tibia and fibula fracture and infection after follow-up at least one year. CONCLUSION: Application of continuous douche and VSD can effectively decrease incidence of complications and promote the refractory tissue, bone and joint infections wound growth, healing and considerably shorten the healing time.

[Isolation, culture and purification of olfactory ensheathing cells from human fetal olfactory mucosa].

OBJECTIVE: To explore the method for obtaining olfactory ensheathing cells from human fetal olfactory mucosa by cell culture for selective adhesion in the presence of neurotrophin-3 (NT3) and low-concentration serum. METHODS: The olfactory ensheathing cells were cultured alternatively in DMEM/F12 culture medium containing 10% fetal bovine serum (FBS) and the medium containing NT3 and 2.5% FBS every 72 h. The cells were observed for morphological changes and identified using immunocytochemistry with P75NTR and GFAP, and the cell purity was estimated. RESULTS: The olfactory ensheathing cells from human fetal olfactory mucosa were positive for P75(NTR) and GFAP, and in in vitro culture, the cells exhibited dipolar or tripolar appearance with long thin neurites. On the 9th day of cell culture, the purity of the olfactory ensheathing cells reached about 83%. CONCLUSION: The olfactory ensheathing cells can be obtained by in vitro culture for selective adhesion in the presence of NT3 and low-concentration serum.

[Culture and purification of olfactory ensheathing cells from human fetal using different attachment rates combined with the technique of using NT3 intermittently].

AIM: To explore a simple and pragmatic method to obtain sufficient olfactory ensheathing cells from human fetal by using different attachment rates in harvested cells with the combinating of the technique of using NT3 intermittently. METHODS: DMEM/F12 culture solution including 100 mL/L of fetal bovine serum or including NT3 was used to culture olfactory ensheathing cells intermittently every 48 h. The conditions and growth degree of OECs were observed, and P75 immunocytochemistry was used to estimate the purity of the cells. RESULTS: Human fetal OECs were positive after P75 immunocytochemistry. They appeared to be dipolar or tripolar cells and their processes formed a network in vitro. The purity of OECs in good conditions reached about 95% on 9 d and 83% on 12 d. CONCLUSION: The method of using different attachment rates combined with the technique of using NT3 intermittently can culture and purify OECs simply and effectively.