Morphological characteristics of L 4, 5 facet joints in degenerative lumbar spondylolisthesis / 中华骨科杂志

Objective:To observe the morphological characteristics of L 4, 5 facet joints in patients with degenerative lumbar spondylolisthesis (DLS) of different spinopelvic types based on Roussouly classification. Methods:We retrospectively analyzed 142 patients with DLS who visited the department of orthopaedics in the Affiliated Hospital of Southwest Medical University from August 2018 to May 2022. There were 33 males aged 65.0±10.7 years and 109 females aged 61.8±9.6 years. The following morphological parameters of the L 4, 5 facet joint were measured on the CT images: facet joint angle (FJA), pedicle facet angle (PFA), facet joint tropism (FT) and facet joint osteoarthritis (OA) degree; the sacral slope (SS), lumbar lordosis (LL) and percentage of L 4 slip distance (SDP) were measured on preoperative standing neutral lumbar radiographs. According to the Roussouly classification, the patients were divided into four groups (type I, type II, type III, and type IV). The differences of morphological parameters of the facet joints and SDP were compared among the four groups, and the correlation between the FJA and PFA was analyzed. Results:There were 142 patients, including 28 type I, 50 type II, 43 type III, and 21 type IV according to the Roussouly classification. The SDPs of type I, type II, type III, and type IV were 19.1%±3.4%, 18.6%±3.9%, 21.7%±3.9%, 25.0%±2.4%, respectively. Except for types I and II, there were statistically significant differences in pairwise comparison among all other types ( P<0.05). The FJAs in type I and type II (31.4°±6.3°, 35.2°±6.8°) were larger than those in type III (28.4°±5.6°) and type IV (23.4°±4.5°), and the FJA in type III was larger than that in type IV. Conversely, the FJA in type I was smaller than that in type II. These differences were statistically significant ( P<0.05). The PFAs in type I and type II (113.9°±4.9°, 111.3°±5.6°) were smaller than those in type III (116.3°±4.4°) and type IV (121.8°±3.5°), and the PFA in type III was smaller than that in type IV, while, the PFA in type I was larger than that in type II. These differences were statistically significant ( P<0.05). The degree of OA in both type I and type II was lower than that in type III and type IV, with statistically significant differences ( P<0.05). However, there were no statistically significant differences in the degree of OA between type I and type II and between type III and type IV ( P> 0.05). Additionally, there were no statistically significant differences ( F=0.40, P=0.752) in the FT values among type I, type II, type III, and type IV (5.8°±2.3°, 5.6°±2.4°, 6.1°±1.8°, 5.9°±1.9°). Pearson correlation analysis showed that FJA was negatively correlated with PFA ( r=-0.68, P<0.001). Conclusion:In the slip segment of DLS, the facet joint morphology was part of the joint configuration in different spinopelvic types, not just the result of joint remodeling after DLS. Morphological characteristics of the facet joints and DLS interacted with each other.

Imageology classification and treatment option for atypical Hangman fractures / 中华骨科杂志

Objective The purpose of the retrospective study was to introduce a treatment option for atypical Hangman fractures (AHF) based on a new classification.Methods Sixty-seven patients with Hangman fractures were treated with a comprehensive treatment strategy.Firstly,Hangman fractures were classified as typical or atypical (AHF) lesions using computed tomography scans of the cervical spine.Secondly,AHF was divided into 1 of 4 types (type A1,A2,B1,and B2) devised by us to clarify the feature of injury.Thirdly,the injury status of disco-ligamentous complex (intact/indeterminate/ruptured) was evaluated using magnetic resonance imaging.If it was a stable lesion,conservative treatment was recommended.If not surgical treatment using anterior or/and posterior stabilization and fusion at C2-C3 level was used.Results Fifty-one patients were identified with AHF.According to our classification,thirty patients were classified as type A1,14 cases as typeA2,5 cases as type B1,and 2 cases as type B2 lesions.Thirteen AHF without C2-C3 instability (12 as type A1 and 1 as type B1) were treated with non-operative treatment,and 38 AHF with C2-C3 instability (18 as type A1,14 as type A2,4 as type B1,and 2 as type B2) were treated with operative treatment.Three patients (all with type A1 lesions) with slightly displacement of C2-3 underwent isolated direct screw osteosynthesis.The remaining 35 underwent posterior stabilization and fusion at C2-C3 level:24 patients with posterior approach with C2 lag screws and C3 non-lag screws fixation and fusion (11 as type A1,10 as type A2,2 as type B1,and 1 as type B2);3 patients with posterior approach with C1 and C3 screw-rod fixation and fusion (1 as type A1 and 1 as type B1);7 with anterior approach by C2-3 discectomy and fusion (3 as type A1 and 4 as type A2);and 2 with anterior and posterior approach (1 as type B1 and 1 as type B2).The average follow-up period was 26 months (range,12-86 months).Neck pain improved significantly at 3-month follow-up,and neurologic status improved at least 1 grade in 12 patients with neurologic deficits at final follow-up.Radiological evaluation showed bony fusion in all patients at 12-month follow-up.Radiological evaluation showed that all 13 AHF without C2-C3 instability treated with non-operative treatment gained fractures fusion at 3-6 month follow-up.Posterior approaches with C1 or C2 and C3 screw-rod fixation and fusion were found to obtain a better alignment of C2-C3 and satisfactory fusion of C2 pedicle factures than anterior approach.Conclusion The treatment option for AHF based on a new classification is helpful in managing such fractures,resulting in good clinical and radiological outcomes.C2 lag screws with or without C3 pedicle screws fixation via posterior approach may not only reduce fractures but also obtain alignment of C2-C3 effectively.

Outcome of posterior pedicle screw fixation combined with bucking bar technique in treatment of C2 pedicle fractures / 中华创伤杂志

Objective To evaluate the efficacy of pedicle screw fixation combined with bucking bar technique in treatment of C2 pedicle fractures.Methods A retrospective case series study was conducted for 26 cases of C2 pedicle fractures undergone posterior pedicle screw fixation after putting the bucking bar on the anterior surface of C2 via oral cavity from April 2004 to April 2014.There were 19 males and 7 females,with a mean age of 42 years (range,27-71 years).Bilateral C2 pedicle screw placement status,operation time and intraoperative blood loss were recorded.American Spinal Injury Association (ASIA) impairment scale and Visual Analogue Scale (VAS) were used for outcome evaluation.Fracture reduction and symptoms such as sore throat,expectoration,hoarse voice,dysphagia and condition of posterior pharyngeal wall were detected after operation.Results Pedicle fixation of C2 pedicle fractures was completed successfully in 21 cases,repeat C2 pedicle fixation took place in three,and C1-3 fixation was conducted for two.Operation time was (83.2 ± 16.6) min and blood loss was (171.2 ± 115.5)ml.One of the cases experiencing repeat manipulation for screw insertion had transient body balance disorder caused by cerebellar ischemia and recovered within 2 days.X-ray and CT showed complete reduction in 17 cases and incomplete reduction in nine cases.Bony fusion was obtained 6 months after operation.Twenty cases were followed up for 3-46 months (mean,26 months).Final follow-up showed anatomical reduction and bony healing in 19 cases,while malunion in other three cases.ASIA grade improved from C to D in one case,whereas the rest showed a complete neurological recovery (ASIA grade E).VAS improved from preoperative 3-8 points [(5.2 ± 2.5) points] to 0-4 points [(1.6 ±1.5) points] at the final follow-up (P ＜ 0.05).Mild swollen sore throat occurred in four cases after operation.Laryngoscopy showed injury to the posterior pharyngeal wall mucosa (Grade Ⅰ in six cases and Grade Ⅱ in two cases),which were healed within 5-7 days after operation.Conclusion For C2 pedicle fractures,pedicle screw fixation combined with bucking bar technique via oral cavity benefits fracture reduction and stability without apparent impairment to the soft tissue of pharyngeal mucosa.

Hepatocyte apoptosis and mitochondrial permeability transition pore opening in rats with nonalcoholic fatty liver / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the role of hepatocyte apoptosis and mitochondrial permeability transition pore (MPTP) opening in the pathogenesis of nonalcoholic fatty liver disease (NAFLD).</p><p><b>METHODS</b>Thirty male SD rats were randomized into normal diet group and high-fat diet group. At 4, 8 and 12 week of feeding. The hepatocyte apoptosis index (AI) was measured using flow cytometry, and MPTP opening was evaluated with ultraviolet spectrophotometry. Immunohistochemistry was employed to detect hepatic expressions of Bcl-2 and Bax, and Western blotting was used to detect Bax protein expression changes.</p><p><b>RESULTS</b>High-fat feeding resulted in significantly increased hepatocyte AI at 4-12 weeks and gradually increased MPTP opening. In the high-fat diet group, hepatic Bcl-2 expression was detected but the positive cell number remained stable, whereas Bax-positive cell number increased steadily with time with progressively increased intensity of Bax protein expression, resulting in gradually decreased Bcl-2/Bax ratio.</p><p><b>CONCLUSION</b>Hepatocyte apoptosis occurs in the rat model of NAFLD in close correlation with mitochondrial damage. Increased MPTP opening as the result of increased Bax expression and aberrant Bcl-2/Bax ratio is an important mechanism of hepatocyte mitochondrial damage in NAFLD.</p>

Feasibility of manubrium sterni cancellous bone plus pyramesh in anterior cervical spinal fusion surgery / 中国组织工程研究

BACKGROUND: Current commonly used bone graft materials include cancellous bone or bone blocks from ilium, tibia, fibula and others. There is no report of bone graft and fusion in cervical spine from manubrium sterni. OBJECTIVE: To measure lateral X-ray of cervical vertebrae with no degeneration and manubrium sterni samples to explore feasibility of autologous cancellous bone graft of manubrium sterni with pyramesh in anterior cervical spinal fusion surgery, so as to develop a new source of autogenous bone graft.METHODS: A total of 40 manubrium sterni specimens were selected and the length, maximum width and minimum width, thickness, anterior and posterior cortex thickness of manubrium sterni were measured. Manubrium sterni area was calculated: the length, maximum width and minimum width were 4 mm reduced from those of manubrium sterni, its thickness was 2 mm reduced from that of manubrium sterni. The formula of measuring the manubrium sterni volume is (maximum width of manubrium sterni + the minimum width of manubrium sterni)×length of manubrium sterni × thickness of manubrium sterni×1/2. Intervertebral height and vertebral height from C2 to C7 were measured from lateral cervical radiograph of 106 patients with cervical radiolopathy, and the length of pyramesh needed in anterior cervical spinal surgery for one, two, three discs resection, one vertebra plus two discs resection and two vertebrae plus three discs resection was calculated. RESULTS AND CONCLUSION: The manubrium sterni volume was (17 735.51±5 234.92) mm3 and the volume of bone-grafting area was (8 982.83±2 427.76) mm3. The length of pyramesh and volume of bone used in operation were minimal for one disc resection, and maximal for two vertebrae plus three discs resection. The volume of bone graft in the pyramesh was significantly less than the donor area in any anterior cervical spinal fusion operation. Results show that autologous cancellous graft of manubrium sterni combined with pyramesh supporting can be used in anterior cervical spinal fusion surgery. Compared with autologous iliac graft, this method is simpler and does not influence early functional exercise or walking bearing weight.

Management of thoracolumbar burst fracture through anterior approach with preserved posterior vertebral wall / 中华创伤杂志

Objective To evaluate the clinical result and feasibility of anterior approach with posterior vertebral wall preserved in the treatment of thoracolumbar burst fracture with or without paraplegia. Methods From 2005 to 2010, 68 patients with thoracolumbar burst fracture were treated by corpectomy, strut graft and instrumentation with preserved posterior vertebral wall. There were 49 males and 19 females at average age of 39.8 years (16-62 years). Kyphotic Cobb' s angle and spinal stenotic rate was measured preoperatively and postoperatively. The neurological status was evaluated with Frankel impairment scale. Results All patients were successfully managed with this technique, with no neurological deteriorations, cerebrospinal fluid leakage or incision infections except for the pneumothorax in three patients who were then cured through expectant treatment. Screw distraction was performed for restoration of the disc height and kyphosis in 68 patients. After the fractured fragment became loose and was removed, the dura matter was exposed in 19 patients including the eerebrospinal fluid leakage in three patients. Retrograde lumbar myelography was applied in eight patients, of whom there found the blocked spinal canal in three patients and excision of the posterior vertebral wall was performed. Lack of vertebral distraction was found in two patients and extraction of the reversed bone fracture behind the posterior longitudinal ligament was performed in one. The preservation rate of the posterior vertebral wall was 95% (65/68). Fifty-two patients were followed up for mean 2.2 years (from 3 months to 4.5 years) ,which showed no lower back kyphosis. There showed 1-3 Frankel grades of improvement in spinal cord function except for five patients at Frankel grade A. The Cobb angle was average 18.2° in 68 patients preoperatively and was corrected to 9.7°in 52 patients at last follow-up. CT scan showed that the stenotic rate was 42% preoperatively and 9% at final follow up in 68 patients,with no breakage of the screw and plate. Conclusion In the management of thoracolumbar burst fractures,anterior approach is helpful for preservation of the posterior vertebral wall.

Application of bioactive artificial vertebrae of nano-hydroxyapatite and polyamide 66 to anterior approach of osteoporotic thoracolumbar burst fractures / 中国组织工程研究

BACKGROUND: During thoracolumbar anterior operation, implant collapse is an important factor for affecting outcome in patients with thoracolumbar fracture. In particular, osteoporotic patients commonly developed implant collapse, nail channel loose, bone disunion, kyphosis deformation. Bioactive artificial vertebrae of nano-hydroxyapatite and polyamide 66 (n-HA/PA66) has good biocompatibility and biological safety and is an ideal substitute for vertebral body bone graft. OBJECTIVE: To investigate the efficacy of the bioactive artificial verteificial vertebrae of nano-hydroxyapatite and polyamide 66 (n-HA/PA66) for osteoporotic thoracolumbar burst fracture. DESIGN, TIME AND SETTING: A retrospective case analysis was conducted at the Department of Spinal Surgery, Affiliated Hospital of Luzhou Medical College from January 2004 to January 2008. PARTICIPANTS: A total of 20 patients with moderate and severe osteoporotic thoracolumbar fracture (6 males and 14 females) aged 51 -82 years, with an average of 69 years were enrolled in this study. There were 17 cases of fresh fracture and 3 cases of old fracture. n-HAyPA66 was produced by the Sichuan Guona Science and Technology Co., Ltd. This artificial vertebral body was in 10-35 mm diameter, 30-100 mm length, circular cylinder shape, 3-12 mm midheaven diameter, 2.5-6.5 mm tubal wall thickness, with the presence of 2 mm holes surrounding the vertebral body. The contact area of the vertebral body was 78.5-176.7 mm2. Fixity was anterior nail plate system (titanium alloy material) produced by Foshan Shitaibao Company. METHODS: Following conventional tracheal intubation and general anesthesia, at right arm recumbent, according to various fracture-involved segments, different regions were incised and treated with anterior decompression, implanted with artificial vertebrae with the bioactive artificial verteificial vertebrae n-HA/PA66 and fixed with steel plate. MAIN OUTCOME MEASURES: Fracture healing and implant loose were observed by radiograph. Cobb angle, the height of damaged vertebral body and spinal cord function score were compared prior to surgery, 3 months following surgery and the last follow-up. RESULTS: All the patients were successfully operated. Bleeding 200-800 mL during surgery and operation time ranged from 2.0 to 3.0 hours. There were 1 case of pulmonary infection and 1 case of delayed wound healing. A total of 20 patients were followed up for 6-42 months (averagely 18 months). Postoperative radiograph review demonstrated that closed vertebral body was healed three to four months. No significant displacement of implant was found. There was less loss of reestablished vertebral body height. Internal fixation position was good, without nail breakdown or internal fixation loose/displacement. At 3 months following surgery, significant differences in Cobb angle, the height of damaged vertebral body and spinal cord function score were detected compared with that before surgery (P < 0.05). No significant difference in postoperative two follow-up was detected (P > 0.05). CONCLUSION: The bioactive artificial vertebrae of n-HA/PA66 can increase the fusion area, reduce local pressure and prevent loosening of implants and sinking into the vertebrae, finally resulting in restoration of vertebral body height.

Treatment of spinal cord injury with intravenous administration of bone marrow stromal cells in rats / 中华创伤杂志

Objective To observe the effect of intravenous administration of bone marrow stromal cells (BMSCs) on the functional recovery after spinal cord injury in rats.Methods BMSCs harvested from 10 donor adult Sprague-Dawley rats were isolated,cultured,purified,amplified and labeled with bromodeoxyuridine (BrdU ).A total of 66 adult Sprague-Dawley rats were subjected to weight-drop impact causing complete paraplegia and randomly divided into three groups seven days after injury.Group A (22 rats) was treated with 2 × 106 BMSCs cultured in 1 ml phosphate-buffered saline by tail vein,Group B (22 rats) was treated with 1 ml Dulbecco' s modified Eagle medium and Group C (22 rats) was set as blank control group.The distribution and differentiation of donor cells in spinal cord were observed in recipient rats by using immunohistochemical staining and expressions of growth associated protein-43 ( GAP-43),neurofilament 200 (NF200) and nestin in the contused spinal cord measured at 2,3 and 6 weeks respectively after injection.The motor function of three groups was evaluated by the Basso-Beattie-Bresnahan ( BBB) scores at 1,2,3,4,5 and 6 weeks respectively after injection.Results BrdU-reactive cells were mainly distributed through the contused and near regions of spinal cord at 2,3 and 6 weeks after injection.The survived cells in contused spinal cord accounted for 4.9% ,4.4% and 2.6% of the total injection cells at 2,3 and 6 weeks respectively after injection.Two weeks after injection,BMSCs were mainly round or ellipse in shape,12.6% BrdU-reactive cells expressed glial fibrillary acidic protein (GFAP) and 5.4% expressed the neuronal nuclear antigen (NeuN).The expressions of GAP-43,NF200 and nestin were detected at 2,3 and 6 weeks after injection,with significant higher level in Group A than that in Groups B and C (P<0.05).BBB score in Group A was significantly higher than that in Groups B and C 3-6 weeks after transplantation (P<0.05).Conclusions With intravenous administration after spinal cord injury,BMSCs migrate and survive into contused spinal cord,exhibit site-dependent differentiation,up-regulate the expressions of GAP-43,NF200 and nestin,ameliorate nerve function and can be used for treatment of spinal cord injury.

Posterior atlantoaxial fixation using vertex multiaxial screw system / 生物医学工程学杂志

This study aims to assess the effectiveness and advantages of Vertex multiaxial screw system in use for stabilizing the atlanto-axial junction. The entry point of the atlas was located 18-20 mm lateral to the midline and 2.0 mm superior to the inferior border of posterior arch, and the direction of screw was chosen to be about 10 degrees medial to the sagittal plane and about 5 degrees cephalad to the transverse plane. In odontoid vertebra (C2), the direction of the drill bit was guided directly by the medial and superior aspect of the individual C2 pedicle. All screws were placed properly without incidence of nerve or blood vessel injury, and no complication appeared in operation and after surgery. All cases were followed up for an average of 9 months, all cases achieved well reposition and fixation of atlantoaxial joint, average JOA grade was 9.6 before preoperation and 15.9 after operation. Fixation of the atlantoaxial complex using Vertex multiaxial screw system seemed to be a reliable technique and should be considered a good alternative in atlantoaxial fusion. The technique could be used in young patiens.

Optimization of the method to culture rat embryonic neural stem cells in vitro / 中国组织工程研究

AIM:Neural stem cells can be induced to differentiate into various types of neural cells such as neurons and neuroglia cells,but the technique of depuration and cultivation does not consummate.This article determines the optimal culture technique of neural stem cells by different culture concentrations and passage methods. METHODS:Experiments were conducted from May to December 2006 at Laboratory of Transplantation Immunity of Sichuan University.①Clean pregnant female rats(embryonic age range from 12-16 days)and the disposition of animal met ethical standard.②The cerebral cortex of rat embryos were collected,and digested with trypsin and ethylenediamine tetraacetic acid mixture to obtain signal cell suspension.They were cultured in serum-free medium (DMEM/F12 medium containing B27,basic fibroblast growth factor and epidermal growth factor).The 3~(rd)passage cells were collected,and incubated at 1?10~7 L~(-1),1?10~8 L~(-1),1?10~9 L~(-1),1?10~(10)L~(-1),respectively.In addition,neural stem cells were collected 7-10 days after primary culture to harvest formative cell masses.Mechanical blow refers to soft blowing with haustorial tube from thick to thin after centrifugation,or sterile syringe with No.5 pinhead blowing cells when the blow was 5 times.Bubble production was avoided during the operation.Trypsin aspiration combined with mechanical blow refers to trypsin was added after centrifugation,at 37℃for 10 minutes,the neural stem cells were lightly blown with haustorial tube polished with flame or blown with sterile syringe with No.5 pinhead,and then fetal bovine serum was added to stop digestion.③The growth characteristic of the 3~(rd)passage cells at different culture concentration was observed and proliferation was measured at days 1,3,5 and 7 by MTT assay.The neural clone spheres of subcultured was counted to determine the optimal passage way.Immunofluorescence was carried out to detect nestin(special marker to neural stem cells),BrdU,neurone specific enolase,glial fibrillary acidic protein. RESULTS:①Growth characteristics and identification of rat embryonic neural stem cells in vitro:The dissociated neural stem cells from the cerebral cortex of rat embryos were continuously harvested and purified by suspension cultures to get the daughter cell clone.Nestin positive cells could be found in the neurospheres and after attachment they could differentiate into neurone specific enolase and glial fibrillary acidic protein positive cells,and immunofluorescence showed a great of BrdU-positive cells.②The effect of different incubated number of neural stem cells on proliferation:When the neural stem cells planted at the concentration of 1?10~9 L~(-1),the growth rate of the cells was the highest of all concentrations.The number of clone spheres exceeded others at concentration 1?10~7 L~(-1),1?10~8 L~(-1)and 1?10~10 L~(-1)(P

Analysis of complication in anterior decompression and fixation technique for thoracolumbar fractures in cases with concomitant paraplegia / 中华创伤杂志

Objective To discuss causation and clinical treatment of complication in anterior decompression and fixation technique (ADFT) for thoracolumbar fractures with associated paraplegia. Methods A total of 204 cases that had thoracolumbar fractures with paraplegia were operated with ADFT from 1998 to 2004. Of all, 51 times (34 cases) of complication took place. Change of Cob angle was measured according to X-film of thoracolumbar spine before and after operation. Meanwhile, sensation and motion of patients was evaluated. Results There was incision infection leading to septic cerebo-meningtis in one case, CSF leakage in seven, pneumothorax in eight, rib nerve-root injure in five, lumbar nerve-root injure in two, genitofemoral nerve injure in three, lateral femoral cutaneous nerve injure in two, kyphosis in three, deep venous thrombosis in three and eight times of skin-temperature change. X-film that was taken after operation for all patients showed scolisis in five cases. A follow up for 3-6 years (average 2.5 years) was performed in 84 cases, of which seven cases had chronic low-back pain, six scolisis and five kyphosis. No patient showed complications such as screw breakage, plate breakage, fixation device loosening and pseudo-articulation in thoracolumbar spine. Conclusions Many complications can be avoided if we master well anterior decompression and fixation technique of thoracolumbar fracture, reduce surgical trauma and give appropriate and rational guide for rehabilitation.