Objective To study the changes of blood flow of the already-compressed cauda equina under dynamic burden, high frequency stimulation (HFS) and increased additional compression, and to clarify the mechanism of neurogenic intermittent claudication. Methods Thirty SD rats were divided into 5 groups, 6 in each. All groups were operated with laminectomy of the fifth lumbar verfebra. One hour after the measurement of blood flow,in 4experimental groups, the silicon sheets were inserted into the spinal canal of L4 and L6 to cause double level compression of cauda equina by 30%. Two hours after onset of compression, no dynamic burden was introduced to the subjects of the experimental group 1. Only HFS was introduced to the subjects of the experimental group 2 for 6 minutes. Both HFS and increased additional compression were introduced to the subjects of the experimental group 3 for 6 minutes. While only increased additional compression was introduced to the subjects of the experimental group 4 for 6 minutes. The subjects of control group only underwent laminectomy of the fifth lumbar vertebra and HFS 6 minutes. The blood flow of cauda equina was measured with laser Doppler flowmeter. Results In the first 2 hours, there was no significant change of cauda equina blood flow in the control group. During the time of HFS, the blood flow increased significantly to 186.4%±31.5% of initial value (Plt;0.05). In the experimental group 1, there was no blood flow change during the period of dynamic burden(110.4%±7.5%,Pgt;0.05). After introduction of dynamic burden, there was no blood flow changes in the experimental group 2 (111.6%±17.6%,Pgt;0.05). The blood flow in the experimental group 3 decreased to 65.3%±10.7% of initial value (Plt;0.05); and the blood flow in the experimental group 4 decreased to 60.1%±9.2% of initial value (Plt;0.01). There was no significant difference between the experimental groups 3 and 4 (Pgt;0.05). Conclusion The results above show that during the period of increased impulse transmission, double level compression of cauda equina may limit the increase of blood flow, which maycause relative ischemia. If there is increased additional compression along with increased impulse transmission, the blood flow will decrease significantly, which will cause absolute ischemia.
Objective To compare the curative effect of dynamic hi p screw (DHS) combined with anti-rotation screw and cannulated screw in treating patients with Pauwels type II or III femoral neck fracture and to provide the basis for the choice of surgical procedure. Methods Between March 2008 and September 2009, 51 patients with fresh Pauwels type II or III femoral neck fracture were treated with DHS combined with anti-rotation screw (DHS group) and three cannulated screws (cannulated screw group). The DHS group included 23 patients, 13 males and 10 females, aging 27-59 years (mean, 43.2 years); fracture was caused by fall ing in 1 case, by traffic accident in 17, by fall ing from height in 5 with a mean time of 27 hoursfrom injury to hospital ization (range, 12-70 hours); and 23 fractures included 9 Pauwels type II and 14 Pauwels type III femoral neck fracture. The cannulated screw group included 28 patients, 12 males and 16 females, aging 20-60 years (mean, 40.7 years); fracture was caused by fall ing in 1 case, by traffic accident in 22, by fall ing from height in 5 with a mean time of 25 hours from injury to hospital ization (range, 9-38 hours); and 28 fractures included 12 Pauwels type II and 16 Pauwels type III femoral neck fracture. There was no significant difference in the basel ine characteristics between 2 groups (P gt; 0.05). Results The incision heal ing of both groups by first intention was achieved. There were significant differences in operation time, incision size, operation blood loss, the cases of blood transfusion, the amount of blood transfusion, C reaction protein level on the 2nd postoperative day, and hospital ization days between 2 groups (P lt; 0.05). In DHS group, anatomic reduction was observed in 20 cases (86.96%) and satisfactory reduction in 3 cases (13.04%), while in cannulated screw group, anatomic reduction was observed in 25 cases (89.29%) and satisfactory reduction in 3 cases (10.71%) ; there was no significant difference (χ2=0.660, P=1.000). The patients were followed up 12-30 months with an average of 14.8 months. There was no significant difference (P gt; 0.05) in the rate of nonunion (10.71% vs. 0), the implant failure (3.57% vs. 0), and avascular necrosis of the femoral head (10.71% vs. 0) between the DHS group and the cannulated screw group. The union time was (94.5 ± 2.0) days in the DHS group and (106.0 ± 33.5) days in the cannulated screw group, showing no significant difference (t=—1.641, P=0.107). The re-opereation rates and the overall success rates were 25% and 75% in the cannulated group and were 0 and 100% in the DHS group, showing significant differences (χ2=6.650, P=0.012). At last follow-up, there was no significant difference in Harris hip score and visualanalogue scale (VAS) score between DHS group and cannulated screw group (P gt; 0.05). Conclusion The optimal treatment of young adults Pauwels type II or III femoral neck fracture is DHS combined with anti-rotation screw with an high overall success and less compl ications.
Objective To compare the balance of simple randomization, stratified blocked randomization and minimization. Methods Monte Carlo technique was employed to simulate the treatment allocation of simple randomization, stratified blocked randomization and minimization respectively, then the balance of treatment allocation in each group and the balance for every prognostic factor were compared. Results The simulation demonstrated that minimization provides the best performance to ensure balance in the number of patients between groups and prognostic factors. Balance in prognostic factors achieved with stratified blocked randomization was similar to that achieved with simple randomization. Conclusion Minimization offers the best balance in the number of patients and prognostic factors between groups.
ObjectiveTo explore the morphological and functional features of tissue engineered composite constructed with bone mesenchymal stem cells (BMSCs) as seeding cells, thermosensitive collagen hydrogel (TCH) and poly-L-lactic acid (PLLA) as the extracellular matrix (ECM) scaffolds in the dynamic culture system. MethodsBMSCs were separated from long bones of Fischer344 rat, and cultured; and BMSCs at the 3rd generation were seeded on the ECM scaffold constructed with braided PLLA fiber and TCH. The BMSCs-ECM scaffold composite was cultured in the dynamic culture system which was designed by using an oscillating device at a frequency of 0.5 Hz and at swing angle of 70° (experimental group), and in the static culture system (control group) for 7 days. The general observation and scanning electron microscopy (SEM) observation were performed; total DNA content was measured at 0, 1, 3, and 7 days. ResultsPLLA was surrounded by collagen to form translucent gelatiniform in 2 groups; and compact membrane developed on the surface of PLLA. SEM observation showed that BMSCs had high viability and were fusiform in shape with microvilli on the surface of cells, and arranged in line; collagen and cells filled in the pores of PLLA fiber in the experimental group. The cells displayed a flat shape on the surface; there were less cells filling in the pores of PLLA fiber in the control group. At 1, 3, and 7 days, total DNA content in the experimental group was significantly higher than that in control group (P < 0.05). The total DNA content were increased gradually with time in 2 groups, showing significant difference between at 0 day and at 7 days (P < 0.05). ConclusionThe ECM constructed with TCH and PLLA has good biocompatibility. The dynamic cultivation system can promote the cell proliferation, distribution, and alignment on the surface of the composite, so it can be used for tissue engineered composite in vitro.
Objective To gain accurate imaging information of biliary tract after surgery. MethodsThe biliary tract of 170 cases after surgery had been observed dynamically from different directions for longer time. The results of data on biliary tract change were stored in disc, or picture. ResultsOf 170 cases, 120 cases were cured without any abnormal change on cholangiography, and then the Ttube was removed. Of another 50 cases, 30 cases revealed remnant stone on cholangiography, 9 cases showed inflammatory stricture of biliary tract, 4 cases displayed common bile duct tumor, and 7 cases had false fillingdefect. Then, the results were further confirmed by sonography, CT, choledochoscopy, and operation. Conclusion The dynamic observation of biliary tract by Ttube cholangiography after surgery is usual way that is handy, practical, painless, and economic.
ObjectiveTo compare the clinical effects of early dynamic brace passive activity program and average delay activity program after the repair of extensor tendon. MethodsSeventy-eight patients undergoing repair of the extensor tendon during the period from December 2008 to October 2011 in our hospital were randomly divided into two groups.The treatment group had 36 patients who were treated with early dynamic brace passive activity program,and the other 42 patients belonged to the control group and they accepted delay activity program.TAM and FIM were used to evaluate their clinical effects six and eight weeks after surgery,respectively. ResultsThe results of TAM and FIM of the treatment group were significantly better than those of the control group (P<0.01). ConclusionThe early dynamic brace passive activity after extensor tendon injury repair can improve the clinical effect and is worth popularizing.
ObjectiveTo compare the therapeutic effect between intramedullary fixation and external fixation on intertrochanteric fracture. MethodsBetween June 2005 and June 2011, 32 patients with Evans-Jensen type Ⅲ intertrochanteric fracture were treated with proximal femoral nail anti-rotation (PFNA), Gamma nail, dynamic hip screw plate (DHS) or locking compression plate (LCP), separately. The operation duration, peri-operative bleeding, load time, Harris hip score and postoperative complications were observed in the patients, and were used to analyze the therapeutic effect among the four methods. ResultsShorter operation duration, less bleeding in the surgery, smaller quantity of drainage after the operation (P<0.05) were found in group Gamma and group PFNA compared with those in group DHS and LCP. The duration of hospitalization didn't differ much between the two fixation systems (P>0.05). The difference in operation duration, operative bleeding and post-operative drainage between group Gamma and PFNA, and between group DHS and LCP was not significant (P>0.05). ConclusionThe intramedullary fixation was better than external fixation for Evans-Jensen type Ⅲ intertrochanteric fracture.
Existing emotion recognition research is typically limited to static laboratory settings and has not fully handle the changes in emotional states in dynamic scenarios. To address this problem, this paper proposes a method for dynamic continuous emotion recognition based on electroencephalography (EEG) and eye movement signals. Firstly, an experimental paradigm was designed to cover six dynamic emotion transition scenarios including happy to calm, calm to happy, sad to calm, calm to sad, nervous to calm, and calm to nervous. EEG and eye movement data were collected simultaneously from 20 subjects to fill the gap in current multimodal dynamic continuous emotion datasets. In the valence-arousal two-dimensional space, emotion ratings for stimulus videos were performed every five seconds on a scale of 1 to 9, and dynamic continuous emotion labels were normalized. Subsequently, frequency band features were extracted from the preprocessed EEG and eye movement data. A cascade feature fusion approach was used to effectively combine EEG and eye movement features, generating an information-rich multimodal feature vector. This feature vector was input into four regression models including support vector regression with radial basis function kernel, decision tree, random forest, and K-nearest neighbors, to develop the dynamic continuous emotion recognition model. The results showed that the proposed method achieved the lowest mean square error for valence and arousal across the six dynamic continuous emotions. This approach can accurately recognize various emotion transitions in dynamic situations, offering higher accuracy and robustness compared to using either EEG or eye movement signals alone, making it well-suited for practical applications.
ObjectiveTo discuss the safety and effectiveness of combined dynamic cervical implant (DCI) and Cage fusion in the treatment of two-level cervical disc protrusion. MethodsBetween September 2009 and June 2011, 16 cases of two-level cervical disc protrusion were treated with combined DCI and Cage fusion. Of 16 cases, 10 were male and 6 were female, with a mean age of 44.1 years (range, 37-64 years) and with a mean disease duration of 5.1 years (range, 2-8 years), including 8 cases of cervical myelopathy, 5 cases of nerve root cervical myelopathy, and 3 cases of mixed cervical myelopathy. Radiological results indicated degenerative intervertebral discs and compressed never root or spinal cord. Involved discs included C3,4 and C4,5 (1 case), C3,4 and C5,6(5 cases), C4,5 and C5,6 (3 cases), C4,5 and C6,7 (5 cases), and C5,6 and C6,7 (2 cases). The neck disability index (NDI), Japanese Orthopedic Association (JOA) score, and visual analogue scale (VAS) were used to evaluate the neurological function and pain relief. The stabilities and activities of involved segments, intervertebral fusion, and displacement of Cages were observed during follow-up. ResultsPrimary healing of incisions was obtained in all cases; no complication of hematoma, infection, cerebrospinal fluid leakage, or neural function damage occurred. All 16 patients were followed up 18 months on average (range, 6-36 months). The cervical X-ray results indicated that the activities of involved segments was (7.8±3.1)°, showing no significant difference (t=0.655, P=0.132) when compared with preoperative value [(7.3±2.6)°]. No implant loosening was observed; slight heterotopic ossification occurred in 1 patient at the posterior rim of intervertebral space. No cage loosening or sinking was seen, and good fusion was achieved. The mean time of fusion was 4.5 months (range, 3-8 months). NDI, JOA, and VAS scores at last follow-up (18.3±5.1, 15.7±1.5, and 3.4±1.8 respectively) were significantly improved (t=2.131, P=0.016; t=3.126, P=0.024; t=6.102, P=0.038) when compared with preoperative scores (49.6±11.3, 12.8±2.0, and 6.7±1.2 respectively). ConclusionA combination of DCI and intervertebral Cage fusion has satisfactory early effectiveness in treatment of two-level cervical intervertebral protrusion for maintaining the stability and activity of cervical vertebrae.
OBJECTIVE: To study the changes of neural electrophysiology properties of cauda equina under double level compression and dynamic burdens, and to clarify the mechanisms of intermittent neurogenic claudication. METHODS: Thirty SD rats were divided into 5 groups (6 in each group). The laminectomy of L5 was performed in control group. In the experimental groups, the silicon sheets were inserted into the spinal canal of L4 and L6 to cause double level compression of cauda equina by 30%. Two hours after onset of compression, no dynamic burden was introduced in experimental group 1. Only high frequency stimulation(HFS) was introduced for 6 minutes in experimental group 2. Both HFS and additional increased compression were introduced for 6 minutes in experimental group 3. While only additional increased compression was introduced for 6 minutes in experimental group 4. After 6 minutes of dynamic burdens, all were returned to the status of static compression for another 30 minutes and then electrical examination was made. RESULTS: After 2 hours of compression, motor and sensory nerve conduction velocity (NCV) of all the four experimental groups decreased significantly (P lt; 0.05), but there was no significant difference between them. There was no significant change in the control group. There was no significant change of NCV in experimental group 1 during the last 30 minutes of experiment. NCV in the other three experimental groups decreased after introduction of dynamic burdens, especially in the experimental group 3. CONCLUSION: The above results showed that NCV of cauda equina decreased significantly under dynamic burdens during static compression. Two kinds of dynamic burdens introduced at the same time can cause more profound change than a single one.