Research on Target Deviation Measurement of Projectile Based on Shadow Imaging Method in Laser Screen Velocity Measuring System.

In the laser screen velocity measuring (LSVM) system, there is a deviation in the consistency of the optoelectronic response between the start light screen and the stop light screen. When the projectile passes through the light screen, the projectile's over-target position, at which the timing pulse of the LSVM system is triggered, deviates from the actual position of the light screen (i.e., the target deviation). Therefore, it brings errors to the measurement of the projectile's velocity, which has become a bottleneck, affecting the construction of a higher precision optoelectronic velocity measuring system. To solve this problem, this paper proposes a method based on high-speed shadow imaging to measure the projectile's target deviation, ΔS, when the LSVM system triggers the timing pulse. The infrared pulse laser is collimated by the combination of the aspherical lens to form a parallel laser source that is used as the light source of the system. When the projectile passes through the light screen, the projectile's over-target signal is processed by the specially designed trigger circuit. It uses the rising and falling edges of this signal to trigger the camera and pulsed laser source, respectively, to ensure that the projectile's over-target image is adequately exposed. By capturing the images of the light screen of the LSVM system and the over-target projectile separately, this method of image edge detection was used to calculate the target deviation, and this value was used to correct the target distance of the LSVM to improve the accuracy of the measurement of the projectile's velocity.

Transthoracic approach for the treatment of calcified giant herniated thoracic discs.

OBJECTIVE: This study aimed at reporting the results of a transthoracic approach in the treatment of patients with calcified giant herniated thoracic discs (HTDs). METHODS: Fifteen consecutive patients, 11 males and 4 females with a mean age of 46 years (range 33-61), with calcified giant HTDs underwent transthoracic decompression and segmental instrumentation with interbody fusion from November 2004 to September 2010. Clinical data retrospectively examined and compared were levels and types of disc herniation, operative time, blood loss, pre- and postoperative Frankel grades and Japanese Orthopedic Association (JOA) score, and complications. RESULTS: Of the 15 patients, 2 had HTDs at two levels and affected discs were primarily at the T11/12 level (60%). Presenting symptoms included myelopathy, axial back pain, urinary symptoms, and radiculopathy. Disc herniations were classified as central (40%) or paracentral (60%). All discs were successfully removed without dural tears or cerebral spinal fluid leakage. The mean operation time was 179 ± 27 min (range 140-210 min), and the mean estimated blood loss was 840 ± 470 ml (range 300-2,000 ml). Frankel grades improved in 9 patients postoperatively and 12 patients at the last follow-up. The mean JOA score improved from 4.9 to 7.7. All patients reported improvement in symptoms. The average duration of follow-up was 45 ± 24 months (range 7-77 months). CONCLUSIONS: Transthoracic decompression combined with reconstruction, fusion, and fixation is an effective method for the treatment of these lesions and is associated with a low rate of complications, morbidity, and neurological impairment.

[A feasibility research of minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) using hybrid internal fixation for recurrent lumbar disc herniation].

OBJECTIVE: To investigate the feasibility of minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) using hybrid internal fixation of pedicle screws and a translaminar facet screw for recurrent lumbar disc herniation. METHODS: From January 2010 to December 2011, 16 recurrent lumbar disc herniation patients, 10 male and 6 female patients with an average age of 45 years (35-68 years) were treated with unilateral incision MIS-TLIF through working channel. After decompression, interbody fusion and fixation using unilateral pedicle screws, a translaminar facet screw was inserted from the same incision through spinous process and laminar to the other side facet joint. The results of perioperative parameters, radiographic images and clinical outcomes were assessed. The repeated measure analysis of variance was applied in the scores of visual analogue scale (VAS) and Oswestry disablity index (ODI). RESULTS: All patients MIS-TLIF were accomplished under working channel including decompression, interbody fusion and hybrid fixation without any neural complication. The average operative time was (148 ± 75) minutes, the average operative blood loss was (186 ± 226) ml, the average postoperative ambulation time was (32 ± 15) hours, and the average hospitalization time was (6 ± 4) days. The average length of incision was (29 ± 4) mm, and the average length of translaminar facets screw was (52 ± 6) mm. The mean follow-up was 16.5 months with a range of 12-24 months. The postoperative X-ray and CT images showed good position of the hybrid internal fixation, and all facets screws penetrate through facets joint. The significant improvement could be found in back pain VAS, leg pain VAS and ODI scores between preoperative 1 day and postoperative follow-up at all time-points (back pain VAS:F = 52.845, P = 0.000;leg pain VAS:F = 113.480, P = 0.000;ODI:F = 36.665, P = 0.000). CONCLUSION: Recurrent lumbar disc herniation could be treated with MIS-TLIF using hybrid fixation through unilateral incision, and the advantage including less invasion and quickly recovery.

[A feasibility research of unilateral incision minimally invasive transforaminal lumbar interbody fusion using pedicle screws and a translaminar screw hybrid fixation].

OBJECTIVE: To investigate the feasibility and safety of unilateral incision hybrid fixation using pedicle screws and a translaminar screw in minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF). METHODS: From January to June 2010, 18 patients with single-level lumbar disc disease were treated with MIS-TLIF under METRx(TM) X-tube. After decompression and fixation using unilateral pedicle screws, a translaminar screw was inserted from the same incision to the other side. The results of perioperative parameters, radiographic images and clinical outcomes were assessed. RESULTS: All patients underwent MIS-TLIF were accomplished unilateral hybrid fixation without any neural complication. The average operative time was (107 ± 19) min, the average operative blood loss was (62 ± 21) ml, and the average postoperative ambulation time was (21 ± 5) h. The average length of translaminar facets screw was (52 ± 2) mm, and the postoperative images showed all screws penetrate through facets joint. During the follow-up the visual analogue scale and Oswestry disability index scores were significant improved compared with preoperative (F = 42.221 - 259.833, P < 0.01). CONCLUSIONS: Bilateral hybrid fixation could be completed through unilateral incision by pedicle screws and a translaminar screw in MIS-TLIF, and the advantage including less invasion, quickly recovery, short operative time, and saving fixation cost.

[Complication and treatment of the lumbar intervertebral disc herniation using percutaneous endoscopic lumbar discectomy].

OBJECTIVE: To summarize and discuss the lapsus and the treatment of the lumbar intervertebral disc herniation using percutaneous endoscopic lumbar discectomy (PELD). METHODS: Between July 2002 and October 2010, 689 patients with lumbar intervertebral disc herniation treated by PELD were analyzed, including 448 males, and 241 females. Single lumbar intervertebral disc herniation were 669 cases. double lumbar intervertebral disc herniation were 19; three lumbar intervertebral disc herniation were 1. Central type in 66, side central type in 365, lateral type in 242, extreme lateral type in 10, sequestered type in 6. These cases with complications in operation and postoperation were studied retrospectively. RESULTS: There were nucleus pulposus omissions in 5 patients and 2 patients underwent open resection of nucleus pulposus during operation immediately and the second operation was needed in 3 cases, 1 case with transforaminal lumbar interbody fusion (TLIF) and the others with open resection of nucleus pulposus. Two patients had nerve root injury, but all completely recovered in 3 - 6 months after operation. Spinal dura mater disruption was in 2 patients, recovered after suturing of skin wound. All 689 patients were followed up for 6 - 96 months, mean follow-up time was 33 months. Postoperative spondylodiscitis was in 7 patients, recovery after expectant treatment in 1, percutaneous puncture irrigation and drainage for continued use of local antibiotics in 4, posterior infective lumbar discectomy in 2. Postoperative relapse was in 6 patients, operated secondly by PELD in 4 and by TLIF in 2, recovery after the second operation. Nerve root induced hyperalgesia and burning-like nerve root pain was seen in 19 patients, the symptom was improved by analgesic drug, neurotrophy drug and physiotherapy. The effect of single segment PELD was not good in 10 patients with spinal stenosis, who underwent multiple segment TLIF later. CONCLUSIONS: The complications during operation usually are nucleus pulposus omissions, nerve root injury, spinal dura mater disruption. Accordingly the complications after operation include spondylodiscitis, recurrence, nerve root induced hyperalgesia or burning-like nerve root pain. Strict indication, aseptic technique, skilled operation and proper rehabilitation exercise are effective ways to reduce complications.

Functional Network of the Long Non-coding RNA Growth Arrest-Specific Transcript 5 and Its Interacting Proteins in Senescence.

Increasing studies show that long non-coding RNAs (lncRNAs) play essential roles in various fundamental biological processes. Long non-coding RNA growth arrest-specific transcript 5 (GAS5) showed differential expressions between young and old mouse brains in our previous RNA-Seq data, suggesting its potential role in senescence and brain aging. Examination using quantitative reverse transcription-polymerase chain reaction revealed that GAS5 had a significantly higher expression level in the old mouse brain hippocampus region than the young one. Cellular fractionation using hippocampus-derived HT22 cell line confirmed its nucleoplasm and cytoplasm subcellular localization. Overexpression or knockdown of GAS5 in HT22 cell line revealed that GAS5 inhibits cell cycle progression and promotes cell apoptosis. RNA-Seq analysis of GAS5-knockdown HT22 cells identified differentially expressed genes related to cell proliferation (e.g., DNA replication and nucleosome assembly biological processes). RNA pull-down assay using mouse brain hippocampus tissues showed that potential GAS5 interacting proteins could be enriched into several Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, and some of them are involved in senescence-associated diseases such as Parkinson's and Alzheimer's diseases. These results contribute to understand better the underlying functional network of GAS5 and its interacting proteins in senescence at brain tissue and brain-derived cell line levels. Our study may also provide a reference for developing diagnostic and clinic biomarkers of GAS5 in senescence and brain aging.

The long noncoding RNA Synage regulates synapse stability and neuronal function in the cerebellum.

The brain is known to express many long noncoding RNAs (lncRNAs); however, whether and how these lncRNAs function in modulating synaptic stability remains unclear. Here, we report a cerebellum highly expressed lncRNA, Synage, regulating synaptic stability via at least two mechanisms. One is through the function of Synage as a sponge for the microRNA miR-325-3p, to regulate expression of the known cerebellar synapse organizer Cbln1. The other function is to serve as a scaffold for organizing the assembly of the LRP1-HSP90AA1-PSD-95 complex in PF-PC synapses. Although somewhat divergent in its mature mRNA sequence, the locus encoding Synage is positioned adjacent to the Cbln1 loci in mouse, rhesus macaque, and human, and Synage is highly expressed in the cerebella of all three species. Synage deletion causes a full-spectrum cerebellar ablation phenotype that proceeds from cerebellar atrophy, through neuron loss, on to synapse density reduction, synaptic vesicle loss, and finally to a reduction in synaptic activity during cerebellar development; these deficits are accompanied by motor dysfunction in adult mice, which can be rescued by AAV-mediated Synage overexpression from birth. Thus, our study demonstrates roles for the lncRNA Synage in regulating synaptic stability and function during cerebellar development.

A single posterior approach for multilevel modified vertebral column resection in adults with severe rigid congenital kyphoscoliosis: a retrospective study of 13 cases.

We report a multilevel modified vertebral column resection (MVCR) through a single posterior approach and clinical outcomes for treatment of severe congenital rigid kyphoscoliosis in adults. Transpedicular eggshell osteotomies and vertebral column resection are two techniques for the surgical treatment of rigid severe spine deformities. The authors developed a new technique combining the two surgical methods as a MVCR, through a single posterior approach, for surgical treatment of severe congenital rigid kyphoscoliosis in adults. Thirteen adult patients with severe rigid congenital kyphoscoliosis deformity were treated by a single posterior approach using a MVCR technique. The surgery processes included a one-stage posterior transpedicular eggshell technique first, and then expanded the eggshell technique to adjacent intervertebra space through abrasive reduction of the vertebral cortices from inside out. All posterior vertebral elements were removed including the cortical vertebral bone around the neural canal. Range of resection of the vertebral column at the apex of the deformity included apical vertebra and both cephalic and/or caudal adjacent wedged vertebrae. Totally, 32 vertebrae had been removed in 13 patients, with 2.42 vertebrae being removed on average in each case. The average fusion extent was 7.69 vertebrae. Mean operation time was 266 min with average blood loss of 2,411.54 ml during operation. Patients were followed up for an average duration of 2.54 years. Deformity correction was 59% in the coronal plane (from 79.7 degrees to 32.4 degrees ) postoperatively and 33.7 degrees (57% correction) at 2 years follow-up. In the sagittal plane, correction was from preoperative 85.9 degrees to 27.5 degrees immediately after operation, and 32.0 degrees at 2 years follow-up. Postoperative pain was reduced from preoperative 1.77 to 0.54 at 2 years follow-up in visual analog scale. SRS-24 scale was from 38.2 preoperatively to 76.9 at 2 years follow-up postoperative. Complications were encountered in four patients (30.7%) with transient neurology that spontaneously improved without further treatment within 3 months. MVCR technique through a single posterior approach is an effective procedure for the surgical treatment of severe congenital rigid kyphoscoliosis in adults.

Why Don't I Help You? The Relationship between Role Stressors and Helping Behavior from a Cognitive Dissonance Perspective.

This paper proposes that role stressors decrease helping behavior by undermining employees' normative commitment from a cognitive dissonance perspective and social exchange theory. We also propose two competitive assumptions of the moderating effect of perceived organizational support (POS). In this paper, we first examine these hypotheses in Study 1 and then verify the cognitive dissonance perspective in Study 2. In Study 1, we collected data from 350 employees of two enterprises in China. The results indicated that role stressors had a negative link with helping behavior via the mediating role of normative commitment. The results also showed that POS strengthened the negative relationship between role stressors and normative commitment. In Study 2, we invited 104 employees to participate in a scenario experiment. The results found that role stressors had an impact on normative commitment via dissonance. Our studies verified the combination of cognitive dissonance perspective and social exchange theory to explain the impact of role stressors on helping behavior.

[A method to avoid the fixator failure by using pedicle screw combined vertebroplasty for spine fractures].

OBJECTIVE: To study a new implant material (carbonated hydroxyapatite, CHA) united pedicle screw to cure spine fracture. METHODS: Thirty-two cases of spine compressed fracture were used with pedicle screw fixator and vertebroplasty. Before operation, patients' vertebral body were compressed (46 + 21)% (20% approximately 70%) on average. In operation, broken vertebral body was reposition through pedicle screw technique, then used self-made syringe to inject CHA into anterior and central column of broken vertebral body through pedicle. And all of patients were not given any bone-graft. RESULTS: In 6 - 26 months followed-up, no immunologic rejection was found about hydroxyapatite, and no any broken of the screws and shafts was found, no loosing and other complications either. All the patients could move in 3 - 5 days after operation. The height of the broken vertebral body were reduced 97% compared with pre-operation. And CHA in vertebral body was degraded gradually, and at the same time it was replace by new bone in vertebral body. After operation, VAS score was 61 +/- 32, and there was significant difference compared with pre-operation. CONCLUSIONS: The pedicle screw fixation united vertebroplasty is an efficient way to prevent the failure of the treatment of spine fracture.

[Characteristics of nerve root compression caused by degenerative lumbar stenosis with scoliosis].

OBJECTIVE: To investigate the factors that may contribute to radiculopathy in degenerative lumbar stenosis with scoliosis (DLSS) and their association with the pattern of the scoliosis. METHODS: Twenty-seven patients with DLSS were examined in our hospital. The symptomatic nerve roots were determined by pain distribution, and neurological findings. The compressive factors were diagnosed by magnetic resonance imaging and myelography or radiculography. The pattern of scoliosis was determined by plain radiographs. Correlation between the affected nerve root and the compressive factors or the pattern of the scoliosis were then analyzed. RESULTS: Among the 27 patients, L3 root was affected in 6 patients, L4 root in 13 patients, L5 root in 15 patients, and S1 root in 9 patients. L3 and L4 roots were more compressed by foraminal or extraforaminal stenosis on the concave side of the curve, whereas L5 and S1 roots were commonly affected by lateral recess stenosis on the convex side. CONCLUSION: In DLSS, nerve root compression is not only seen on the concave side of the scoliosis, but also equally involved on the convex side. Most radiculopathy in DLSS distributes close to central sacral vertical line, which may be due to the abnormal weight-bearing for the pattern of scoliosis.

Characterization of a developing lumbar arthrodesis in a sheep model with quantitative instability.

BACKGROUND CONTEXT: Mechanical forces have been considered responsible for stress shielding an arthrodesis, but the biology of a developing lumbar fusion has not been well characterized. PURPOSE: A large animal model was used to test the hypothesis that mechanical forces modify the biological processes involved in a developing bony fusion. STUDY DESIGN: Lumbar fusion was performed in an ovine model using custom instrumentation that permitted a controlled degree of anterior-posterior translation after surgery. Fusion sites were evaluated by radiography, microradiography, histology and histomorphometry at time points that corresponded with predicted early and later stages of bone healing. METHODS: Fourteen skeletally mature ewes underwent lumbar spinal fusion under general anesthesia. In the control (stable) group, the spine was rigidly fixed with a cage anteriorly and pedicle screws posteriorly. In the experimental (unstable) group, the spine was destabilized by an annulectomy (with no anterior implant) and custom pedicle screws that allowed 2 mm of anterior-posterior translation. Animals were euthanized 6 and 12 weeks after surgery. RESULTS: Radiographs confirmed that the fusion mass had not fully consolidated at either time point. Microradiographs revealed a trend toward increased bone formation at 6 weeks in the stable case as compared with the unstable, but by 12 weeks, this trend had reversed (p=.03). Intramembranous bone formation was the primary mechanism of healing near the transverse process in animals with both stable and unstable fixation. In the area between the two transverse processes, new bone formation occurred primarily through endochondral ossification. At 12 weeks, the stable case had significantly more cartilage formed (p=.023) but less newly formed bone (p=.07) as compared with the quantitatively unstable. CONCLUSIONS: This clinically realistic animal model allowed characterization of the biology of the developing arthrodesis before fusion. Under stable or unstable conditions, endochondral ossification was the predominant mechanism of new bone formation within the intertransverse process region. This finding, which contrasts with previous reports from small animal models of spine fusion, may reflect a difference in biology that results from the increased size of the intertransverse space in sheep as compared with small animals. Interestingly, mechanical instability increased the formation of new bone within this region, but not at the transverse process. Endochondral ossification therefore appears to respond to mechanical factors in the fusion site. The ovine model shows promise as an alternative to the rabbit model and may provide a more stringent test for potential new surgical and nonsurgical strategies for spine fusion.

[Anterior cervical diskectomy and fusion with allograft and internal fixation].

OBJECTIVE: To evaluate the effect of cylindrical titanium mesh packing cancellous allograft in the anterior cervical fusion for the cervical spondylosis with anterior titanium plate. METHODS: Ninety-eight patients with cervical spondylosis underwent diskectomy and cancellous allograft contained in cylindrical titanium mesh enhanced by anterior titanium plate system. Sixty-four patients were followed up clinically and radiographically. The mean follow-up time was (15.2 +/- 1.7) months. JOA scores and Nurick myelopathy grading system were used for clinical assessment. Roentgenograms were analyzed to identify the stability of fused levels. RESULTS: In all patients of 98 cases, the wounds were normally healed without acute or chronic infection. In statistical analysis of 64 patients followed up, the mean JOA scores was (11.6 +/- 1.8) preoperatively and improved to (16.0 +/- 1.2) at final follow-up (P < 0.05). And the mean Nurick grades were (2.7 +/- 0.7) and (0.7 +/- 0.8) before and after surgery respectively (P < 0.05). The X-ray films demonstrated that no meshes were found displacing or subsiding. New bone formation occurred in the back of meshes at 5 months after surgery. The final follow-up fusion rate was 95%. CONCLUSION: The cancellous allograft impacted into titanium meshes for cervical fusion has gained excellent or good results clinically and radiographically in short term follow-up.

[Allograft fibula in treatment of cervical spondylosis].

OBJECTIVE: To evaluate the efficacy of allograft fibula in anterior cervical fusion for cervical spondylosis patients treated by Smith-Robinson operation supplemented with anterior instrumentation. METHODS: The clinical outcome of 38 patients with cervical spondylosis treated by Smith-Robinson operation using allograft fibula supplemented with anterior titanium plate were retrospectively studied. The patients were followed up on average was (9.5 +/- 3.4) months. The average preoperative and postoperative JOA scores were assessed and myelopathy severity was graded using the Nurick myelopathy grading system. Lateral views in neutral position, in flexion, and in extension of preoperative cervical roentgenograms were analyzed in comparison with last follow-up films to identify the changes in the height of intervertebral space and the quality of fusion. RESULTS: Statistical analysis of all patients revealed mean JOA scores of 12.54 +/- 1.62 and 16.07 +/- 1.13 before surgery and at final examination (P < 0.05), respectively. And the mean Nurick grades were 2.46 +/- 0.43 and 0.72 +/- 0.37 before and after surgery (P < 0.05), respectively. Radiographic follow-up revealed that the height intervertebral space and the lordosis of the cervical spine had been restored and no allograft was found displaced or collapsed and also revealed that all grafts obtained union by 5 months after surgery. CONCLUSIONS: Fibular allograft can replace autologous iliac crest graft in the treatment of cervical spondylosis patients. This method is safe and efficacious and can avoid bone graft-site morbidity.

[Freeze-dried allograft of posterior spinal fusion in patients with scoliosis].

OBJECTIVE: To observe the effectiveness and safety of allograft in posterior spinal fusion in patients with scoliosis. METHODS: 41 cases of 54 scoliosis patients with allograft for spinal fusion were followed up. The mean follow-up time is 16 months. Foreign body reaction was studied clinically and fusion status was assessed radiographically. RESULTS: There was no foreign body reaction significantly in all patients. Acute deep wound infection happened in one patient and no chronic deep wound infection occurred. There was no disease transferred by allograft in followed patients. New bone formation appeared after 4 months postoperatively in radiogram. At final follow-up, the mean angle of 3.4 degrees lost and minimal -1 degrees and maximal 6 degrees . Implants were fastened and did not loosen and fracture. CONCLUSIONS: Allograft for posterior spinal fusion in scoliosis patients was useful and safe.

Application of intraoperative computed tomography with or without navigation system in surgical correction of spinal deformity: a preliminary result of 59 consecutive human cases.

STUDY DESIGN: A retrospective analysis of patients undergoing spinal deformity correction surgery by the assistance of intraoperative computed tomography (iCT) with or without navigation system. OBJECTIVE: To share our preliminary experience and analysis of the iCT navigation system applied to spinal deformity surgery. SUMMARY OF BACKGROUND DATA: The iCT navigation system has been shown to improve accuracy and safety in posterior instrumentation. It not only decreased the operation time but also prevented excessive radiation exposure to the medical staff. To date, there are only few reports about the application of the iCT navigation system in spinal deformity surgery. METHODS: From April 2009 to September 2010, 59 patients who had a diagnosis of scoliosis, kyphosis, or scoliokyphosis and underwent iCT-assisted surgical correction were included. Without randomization, 28 patients were operated with the iCT-navigation system, and the other 31 patients were operated with standard procedure under iCT assistance. The detailed procedures, preoperative and intraoperative images were illustrated. The accuracy of screw placement, time for screw insertion, postoperative correction rate, and iCT scanning data were analyzed. RESULTS: There were significant differences between 2 groups in (1) the preoperative Cobb angle (76.2° and 62.6° in the navigation and non-navigation groups), (2) the accuracy and the revision rate of thoracic pedicle screws and total pedicle screws, and (3) the average screw insertion time. The breach rate and the revision rate of thoracic pedicle screws and total pedicle screws were significantly lower and the average screw insertion time was significantly lesser in the navigation group than in the non-navigation group. There were no statistically significant difference in (1) the breach rate and the revision rate of lumbar pedicle screws, (2) the mean iCT scanning time and time-out, (3) the mean number of fusion segments, (4) the mean number of iCT scans, and (5) the postoperative correction rate. Complications were encountered in 2 patients in the non-navigation group but none in the navigation group. There was no reoperation due to implant malposition in both groups. CONCLUSION: The iCT navigation system provides desirable accuracy of posterior spinal instrumentation for patients during surgical correction of spinal deformity without radiation exposure to the medical staff, especially in thoracic spine instrumentation. Meanwhile, the iCT in itself is an effective means of assessing complex instrumentation of the spinal deformity.

[Analysis of effectiveness of interrupt percutaneous endoscopic lumbar discectomy through interlaminar approach for L5, S1 disc protrusion].

OBJECTIVE: To evaluate the effectiveness of interrupt percutaneous endoscopy lumbar discectomy (PELD) through interlaminar approach for L5, S1 disc protrusion. METHODS: Between November 2006 and August 2010, 115 patients with L5, S1 disc protrusion were treated, including 79 males and 36 females with an average age of 38 years (range, 14-79 years). All patients showed the dominated symptom of the S1 nerve root. The working channel was established by puncturing through interlaminar approach under the local anesthesia. After the needle was used to make sure no nerve root or dural sac on working face, the disc tissue was excised directly by blind sight. Then the nerve root decompression was observed through the endoscope. In patients with free type, fragment compression was observed through the endoscope, and the disc tissue around the nerve roots was removed, then the free disc tissue around intervertebral space was excised. RESULTS: One patient who failed to puncture changed to miniopen discectomy; 3 patients who failed changed to post lateral approach; and the others underwent interrupt PELD through interlaminar approach. Eighty patients were followed up 18 months on average (range, 12-36 months). The average Oswestry Disability Index (ODI) was reduced to 13% +/- 5% at 12 months after operation and to 12% +/- 8% at last follow-up from 73% +/- 12% at preoperation, showing significant differences (P < 0.01). According to modified Macnab's criterion, the results were excellent in 59 cases, good in 15 cases, fair in 3 cases, and poor in 3 cases at last follow-up, and the excellent and good rate was 92.5%. CONCLUSION: For the treatment of disc protrusion at the L5, S1 level, interrupt PELD through interlaminar approach should be ideal with short operation time, small trauma, and quick recovery.

[Preliminary clinical results of endoscopic discectomy followed by interbody fusion using B-Twin expandable spinal spacer].

OBJECTIVE: To investigate the effectiveness and significance of percutaneous endoscopic discectomy followed by interbody fusion using B-Twin expandable spinal spacer for degenerative lumbosacral disc METHODS: Between January 2007 and August 2008, 21 patients with degenerative lumbosacral disc disease were treated with endoscopic discectomy followed by interbody fusion using B-Twin expandable spinal spacer. Among them, there were 13 males and 8 females with an average age of 52 years (range, 28-79 years). And the disease duration ranged from 3 months to 40 years (median, 9 months). The affected segments included T11, 12, T12-L1, L1.2, and L2, 3 in 1 case respectively, L4, 5 in 4 cases, and L5, S1 in 13 cases. All patients had intractable low back pain or lower extremity radicular symptoms. The placement methods of B-Twin expandable spinal spacer were double sides in 15 cases and single side in 6 cases. Oswestry Disability Index (ODI) and Macnab grading were used to determine the function recovery after operation. And Suk's standard was used to determine the fusion effects by X-ray. RESULTS: All 21 patients were followed up 18 months to 3 years (mean, 23.8 months). Sciatica symptoms disappeared after operation in 19 cases, no significant improvement occurred in 2 cases of thoracic disease. The ODI scores were 79% +/- 16% at preoperation, 30% +/- 9% at 1 month, 26% +/- 10% at 3 months, 21% +/- 12% at 6 months, and 20% +/- 10% at 18 months after operation, showing significant differences between pre- and postoperation (P < 0.05). According to Macnab grading at 6 months postoperatively, the results were excellent in 14 cases, good in 5 cases, and fair in 2 cases with an excellent and good rate of 90.5%. According to Suk et al. standard, the results were excellent in 1 case, good in 19 cases, and poor in 1 case with an excellent and good rate of 95.2%. The muscle strength of the lower extremities had no improvement in 1 case of T11, 12 disc protrusion; pedicle screws fixation and decompression laminectomy were given after 6 months, but no improvement was achieved during follow-up. Protrusion recurred after 4 months in 1 case of L4, 5 disc protrusion, then was cured by laminectomy discectomy. The remaining patients achieved postoperative relief. CONCLUSION: Endoscope combined with interbody fusion is a good combination to solve lumbar instability. B-Twin expandable spinal spacer is a minimally invasive fusion choice of 4, 5 and L5, S1.

Treatment of lumbar and lumbosacral spinal tuberculosis with minimally invasive surgery.

OBJECTIVE: To evaluate the outcome of computed tomography (CT)-guided percutaneous puncture and local chemotherapy for tuberculosis (TB) of the lumbar or lumbosacral spine. METHODS: From January 2002 to August 2006, 49 patients with lumbar or lumbosacral spinal TB in whom conservative treatment had failed were treated by minimally invasive surgery. There were 21 female and 28 male patients. The mean age of the patients was 47 ± 18 years (range from 12 to 78 years). There were 40 cases with lumbar TB, and 9 with lumbosacral TB. From L(1) to S(1), the involved vertebral numbers were 8, 26, 19, 19, 21 and 10, respectively. In 3 patients the spinal TB involved a single vertebra, in 39 patients two, in 6 patients three and in only one case four vertebrae. According to the Frankel scale, three patients had grade E incomplete paralysis preoperatively. The outcome, after treatment by CT-guided percutaneous puncture and local chemotherapy, was retrospectively analyzed according to the preoperative and postoperative kyphotic angles and the Oswestry disability index (ODI). RESULTS: Forty-nine patients were followed up for from one year to 5 years and 8 months (average 35 months). All cases recovered, and there was no recurrence. Preoperatively, the kyphotic angle was 16.47°± 8.74°, and it had decreased to 13.35°± 8.02° by the final follow-up (t= 5.79, P < 0.001). The average ODI score had improved from 70.12 ± 22.24 to 12.72 ± 8.62 (t= 21.42, P < 0.001). CONCLUSION: The majority of cases of lumbar and lumbosacral spinal TB can achieve satisfactory results with minimally invasive surgery. Its clinical application is therefore strongly recommended.