Objective To compare the short-term effectiveness between dynamic neutralization system (Dynesys) and posterior lumbar interbody fusion (PLIF) in the treatment of lumbar degenerative disease. Methods The clinical data were retrospectively analyzed, from 14 patients undergoing Dynesys and 18 patients undergoing PLIF to treat lumbar degenerative disease between February 2009 and March 2011. No significant difference in gender, age, duration of disease, and lesion segments was found between 2 groups (P gt; 0.05). The visual analogue scale (VAS) score, Oswestry disability index (ODI), and radiographic results were compared between 2 groups at preoperation and last follow-up. Results Thirty-one cases were followed up 12-21 months (mean, 17 months). No internal fixation loosening, broken screws, and broken rods was found during follow-up. The mean interbody fusion time was 15 months (range, 13-19 months) in PLIF group. The VAS score and ODI were significantly improved in 2 groups at last follow-up when compared with the preoperative ones (P lt; 0.05); but there was no signficant difference between 2 groups (P gt; 0.05). Imaging assessment: the range of motion (ROM) of operated segment in PLIF group was (0.1 ± 0.4)° at last follow-up, showing significant difference when compared with preoperative ROM (7.8 ± 0.6)° (t=28.500, P=0.004); the ROM in Dynesys group (5.0 ± 1.5)° decreased, but showing no significant difference when compared with preoperative ROM (7.5 ± 0.8)° (t=0.480, P=0.113); and significant difference was found between 2 groups (t=5.260, P=0.008) at last follow-up. The ROM of adjacent segment in Dynesys group at last follow-up (7.2 ± 0.7)° decreased when compared with preoperative ROM (7.3 ± 1.8)°, but showing no significant difference (t=0.510, P=0.108); however, ROM of adjacent segment in PLIF group (8.7 ± 0.4)° increased significantly when compared with preoperative ROM (7.0 ± 1.6)°, showing signifcant difference (t=3.440, P=0.042); and there was significant difference between 2 groups (t= — 2.100, P=0.047) at last follow-up. Conclusion Dynesys and PLIF have equivalent short-term effectivness in the treatment of lumbar degenerative disease. However, the Dynesys could retain ROM of operated segment without increased ROM of the adjacent segment, which will promote the disc recovery of operated segment and prevent degeneration of adjacent segment.
Objective To elucidate the new development, structural features and appl ication of the lumbar interspinous process non-fusion techniques. Methods With the review of the development course and important research works in the field of the lumbar inter-spinous process non-fusion techniques, the regularity summary, science induction, and prospect were carried out. Results The lumbar inter-spinous process non-fusion technique was a part of non-fusion insertof spinal division posterior surface. According to the design, it could be divided into two major categories: dynamic and static systems. The dynamic system included Coflex and device for intervertebral assisted motion; the static system included X-STOP, ExtenSure and Wall is. The lumbar inter-spinous process non-fusion technique was a new technique of spinal division, it could reserve the integrated function of intervertebral disc and zygapophysial joint, maintain or recover the segmental movement to a normal level, and have no adverse effect on the neighboring segments. A lot of basic and cl inical researches indicated that lumbar inter-spinous process insert had extensive appl ication to curatio retrogression lumbar spinal stenosis, discogenic low back pain, articular process syndrome, lumbar intervertebral disc protrusion and lumbar instabil ity and so on. Conclusion With the matures of lumbar inter-spinous process non-fusion techniques and the increased study of various types of internal fixation devices, it will greatly facil itate the development of treatment of lumbar degenerative disease. But long-term follow-up is needed to investigating the long-term efficacy and perfect operation indication.
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.
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 evaluate the influence on the estimation of respiratory mechanics with dynamic signal analysis approach during noninvasive positive pressure ventilation (NPPV) under different inspiratory effort conditions. Methods The Respironics V60 ventilator was connected to a ASL5000 lung simulator, which simulate lung mechanics in healthy adults with body weight from 65 to 70 kg, and patients with chronic obstructive pulmonary disease (COPD) and acute respiratory distress (ARDS). Each lung models was subjected to 4 different muscle pressures (Pmus): 0, 5.0, 10.0, and 15.0 cm H2O. Inspiratory pressure support level was adjusted to maintain tidal volume (VT) achieving 7.0 mL/kg outputted by ventilator respectively. Positive end expiratory pressure was set at 5.0 cm H2O and back-up rate was 10 beats per minute. Measurements were conducted at system leaks with 25 to 28 L/min. The respiratory system compliance (Crs), inspiratory and expiratory resistance (Rinsp and Rexp) were estimated by special equations, which was derived from the exhaled VT, flow rate and airway pressure. Results The driving pressure (DP) was decreased with Pmus increasing, and was 1.0 cm H2O after Pmus exceeding 10.0 cm H2O and the VT was larger than 7.0 mL/kg in normal adult model. The estimated value of Crs was affected by the changes of Pmus in all three lung models. The significant underestimation of Raw and the overestimation of Crs were observed when Pmus level exceed 10.0 cm H2O. The measured errors of Crs and Rexp were within 10% in COPD and ARDS model when Pmus was at 5.0 cm H2O. The underestimation of Rinsp was always existed in all Pmus level (P<0.01). Conclusions Using dynamic signal analysis approach, the real-time estimation of respiratory mechanics (Crs and Raw) is no need to interrupt the spontaneous breathing during NPPV. Excessive effort will increase the patient’s inspiratory workload, which is not benefit to accurate estimation of respiratory mechanics.
Objective To compare the effectiveness of the proximal femoral nail antirotation (PFNA) and dynamic hip screw (DHS) in the treatment of elderly patients with intertrochanteric fractures. Methods Between May 2007 and May 2010, 63 elderly patients with intertrochanteric fractures were treated, and fractures were fixed with PFNA in 31 patients (PFNA group) and with DHS in 32 patients (DHS group). There was no significant difference in gender, age, injury cause, disease duration, and fracture type between 2 groups (P gt; 0.05). Results All incisions healed by first intention. The incision length, operation time, and blood loss in PFNA group were significantly less than those in DHS group (P lt; 0.05). The averagefollow-up time was 13.6 months in PFNA group and was 13.8 months in DHS group. The fracture heal ing time was (11.80 ± 1.32) weeks in PFNA group and was (12.21 ± 1.26) weeks in DHS group, showing no significant difference (t=1.23, P=0.29). The complication rate was 0 in PFNA group and was 12.5% (4/32) in DHS group, showing no significant difference (P=0.06). After 1 year, Harris hip score of PFNA group (86.55 ± 10.32) was higher than that of DHS group (80.36 ±11.18) (t=2.28, P=0.03). Conclusion There are two surgical methods to treat intertrochanteric fractures in the elderly patient: PFNA and DHS, and each has advantages; for unstable intertrochanteric fractures, PFNA treatment is the first choice.
Traditional Chinese medicine (TCM) has some unique advantages in the prevention and treatment of cancer. Due to different ideas and mechanism of between TCM and biomedicine in the prevention and treatment of cancer, the clinial effect evaluation approches of biomedicine could not be used as a beneficial method to scientifically evaluate the effects of TCM. From three angles, this article analyzes the key issues regardsing the evaluation methods of TCM as an adjuvant therapy of cancer. It draws lessons from the idea of quality-adjusted survival (QAS), proposes Two-in-One (TIO) method to evaluate the effects of TCM as adjuvant therapy of cancer, which reflects the combined value of the individual patient dynamic information and provides methodological support for the effect evaluation of TCM.
ObjectiveTo investigate the correlation between intima-media thickness (IMT) of carotid artery in color ultrasonography and the heart rate variability. MethodsA retrospective analysis was performed in 64 patients from West China Hospital of Sichuan University between March and May 2013. Carotid intima-media thickness was measured with color ultrasonography and dynamic electrocardiogram, and the heart rate variability was assayed at the same time. ResultsIMT in the cardiovascular disease group, combination group, coronary heart disease group and hypertension group was significantly thicker than the control group (P<0.05). The differences of SDNN and SDANN were statistically significant (P<0.05) between the combination group and the control group. There were 23 cases with IMT ≥ 1.0 mm in the cardiovascular disease group including 8 cases in the combination group, 10 cases in the coronary heart disease group and 5 cases in the hypertension group. IMT in those groups were all significantly higher than that in the control group with only 2 cases having IMT ≥ 1.0 mm (P<0.05). There were 18 cases with SDNN<100 ms in the cardiovascular disease group including 7 cases in the combination group, 6 cases in the coronary heart disease group and 5 cases in the hypertension group, but there was no statistically significant difference compared with that in the control group with only 11 cases (P>0.05). Negative correlation was found between IMT and SDNN, SDANN in the cardiovascular diseases group (r=-0.574, -0.544; P<0.01) and negative correlation was found between IMT and SDANN in the control group (r=-0.392, P<0.05). ConclusionThe carotid artery lesions and autonomic nerve especially sympathetic nerve dysfunction are obvious in patients with cardiovascular diseases and there is a negative correlation between them.
The transmission and interaction of neural information between the hippocampus and the prefrontal cortex play an important role in learning and memory. However, the specific effects of learning memory-related tasks on the connectivity characteristics between these two brain regions remain inadequately understood. This study employed in vivo microelectrode recording to obtain local field potentials (LFPs) from the ventral hippocampus (vHPC) and medial prefrontal cortex (mPFC) in eight rats during the performance of a T-maze task, assessed both before and after task learning. Additionally, dynamic causal modeling (DCM) was utilized to analyze alterations in causal connectivity between the vHPC and the mPFC during memory task execution pre- and post-learning. Results indicated the presence of forward connections from vHPC to mPFC and backward connections from mPFC to vHPC during the T-maze task. Moreover, the forward connection between these brain regions was slightly enhanced after task learning, whereas the backward connection was diminished. These changes in connectivity corresponded with the observed trends when the rats correctly performed the T-maze task. In conclusion, this study may facilitate future investigations into the underlying mechanisms of learning and memory from the perspective of connectivity characteristics between distinct brain regions.
Objective To explore the biomechanical stabil ity of dynamic sleeve three-wing screw for treatment of femoral neck fracture and to provide theoretical basis for choosing dynamic sleeve three-wing screw in cl inical appl ication. Methods Nine human cadaveric femurs were selected and divided randomly into 3 groups (n=3), excluding deformities, fractures, and other lesions. The central neck of the specimens were sawn with hand saw respectively at Pauwels angles of 30, 50, and 70°. All cut ends were fixed with dynamic sleeve three-wing screw. Instron-8874 servohydraul ic mechanical testing machine was used to fixed the specimens which simulated uni ped standing, at the rate of 10 mm/minute and l inear load 0-1 200 N at 11 key points. The strain values of princi pal pressure side and princi pal tension side under different loads were measured. Results There was a peak at 6th point in the 1 200 N load. The strain values at Pauwels angles of 30, 50, and 70° were (—1 657 ± 171), (—1 879 ± 146), and (—2 147 ± 136) με; showing significant differences (P lt; 0.01). The strain values of princi pal pressure side and princi pal tension side of the femoral neck became higher with the increasing Pauwels angle under the same load, showing significant differences (P lt; 0.01). The strain values became higher with the increasing load under the same Pauwels angle (P lt; 0.01). Conclusion Dynamic sleeve three-wing screw has good biomechanical stabil ity for treatment of femoral neck fracture. It explains theoretically that the fracture is more unstable with the increasing Pauwels angle．