Comparison of three different surgical approaches for treatment of thoracolumbar burst fracture / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>The main treatment method used for thoracolumbar fractures is open reduction and internal fixation. Commonly there are three surgical approaches: anterior, posterior and paraspinal. We attempt to compare the three approaches based on our clinical data analysis.</p><p><b>METHODS</b>A group of 94 patients with Denis type A or B thoracolumbar burst fracture between March 2008 and September 2010 were recruited in this study. These patients were treated by anterior-, posterior- or paraspinal-approach reduction with or without decompression. The fracture was fixed with titanium mesh and Z-plate via anterior approach (24 patients), screw and rod system via posterior approach (38 patients) or paraspinal approach (32 patients). Clinical evaluations included operation duration, blood loss, incision length, preoperative and postoperative Oswestry disability index (ODI).</p><p><b>RESULTS</b>The average operation duration (94.1 min +/- 13.7 min), blood loss (86.7 ml +/-0.0 ml), length of incision (9.3 mm +/- 0.7 mm) and postoperative ODI (6 +/- 0.5) were significantly lower (P less than 0.05) in paraspinal approach group than in traditional posterior approach group (operation duration 94.1 min +/- 13.7 min, blood loss 143.3 ml +/-28.3 ml, length of incision 15.4 cm +/- 2.1 cm and ODI 12 +/- 0.7) and anterior approach group (operation duration 176.3 min +/- 20.7 min, blood loss 255.1 ml +/- 38.4 ml, length of incision 18.6 cm +/- 2.4 cm and ODI 13 +/- 2.4). There was not statistical difference in terms of Cobb angle on radiographs among the three approaches.</p><p><b>CONCLUSION</b>The anterior approach surgery is convenient for resection of the vertebrae and reconstruction of vertebral height, but it is more complicated and traumatic. Hence it is mostly used for severe Denis type B fracture. The posterior approach is commonly applied to most thoracolumbar fractures and has fewer complications compared with the anterior approach, but it has some shortcomings as well. The paraspinal approach has great advantages compared with the other two approaches. It is in accordance with the concept of minimally invasive surgery and can replace most posterior approach operations.</p>

Optimized method for isolating and culturing human nucleus pulposus cells / 中国组织工程研究

BACKGROUND: There are different methods to isolate and culture human nucleus pulposus cells, and the differences in digestive enzymes components and digestion time quite are significant. So how to rapidly and efficiently harvest human nucleus pulposus cells has become a research hotspot. OBJECTIVE: To optimize the digestive enzymes components and digestion methods for the preparation of human nucleus pulposus cells. METHODS: Nucleus pulposus tissue specimens were selected from three adult discs in the Department of Orthopedics, China-Japan Union Hospital of Jilin University. The acute traumatic disc tissues that outstanding to the spinal canal were taken under aseptic conditions, and then the peripheral white annulus and jel y-like nucleus pulposus in the center could be seen. According to different mixed enzyme concentration ratio, the samples were divided into two groups. The enzyme Ⅰ group was treated with 0.2% Ⅱ col agenase; and the mixed enzymeⅡ group was digested with 0.25% trypsin for 30 minutes, and then treated with 0.2% Ⅱ col agenase. According to digestion time, each group was divided into three subgroups: 2 hours group, 4 hours group, and overnight group. Final y, suspended cel volume was decided as 2 mL to count cells. Dulbecco’s modified Eagle’s medium containing fetal bovine serum was used for cel culture in vitro. Trypan blue staining was performed to count total cel number and ratio of living cells. Methylthiazolyldiphenyl-tetrazolium bromide assay was used to detect the growth curve of nucleus pulposus cells. RESULTS AND CONCLUSION: Based on the two digestion enzyme concentration, the number of digested cells in the enzyme Ⅰ group was larger than that in the enzyme Ⅱ group after digested for 2 and 4 hours, but the difference was not significant (P > 0.05). Overnight, cellsurvival rate was decreased in the enzyme Ⅰ group after digested for 2 and 4 hours when compared with the enzyme Ⅱ group, and the difference was significant (P < 0.05). After digested for 4 hours, tissue blocks disappeared, and the number of cells reached maximum. The results indicate that enzyme Ⅰgroup composite with Ⅱ col agenase is benefit for the separation of nucleus pulposus cells, and the digestion time is appropriate to 4 hours. This condition has the advantages of simple operation, high efficiency and low cost, and it considered that digestion of nucleus pulposus tissues with 0.2% Ⅱ col agenase for 4 hours is the best condition to obtain nucleus pulposus cells.