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Objective To introduce and analyze the feasibility of a new surgical strategy for circumferential reconstruction of subaxial cervical and cervicothoracic spine by simultaneously combined anterior-posterior approach in the sitting position. Methods A retrospective review was performed for seven patients who underwent the above surgical procedure between July 2011 and January 2015. Among the seven patients, there were six men and one woman, with an average age of 52 years (range, 36-79 years). Six patients were confirmed to have a lower subaxial cervical fracture and dislocation with a locked facet joint, and the other patient had an invasive tumor involving both anterior and posterior parts of vertebrae and lamina, detected by radiological examination. The levels involved for all patients were from C4 to T2. According to American Spinal Injury Association ( ASIA) classification, one case was class A, four were class B, and two were class D. The patients were restricted in the sitting position with traction and a halo in extension to immobilize the head during the operation. The simultaneously combined anterior-posterior operation for reduction, decompression or tumor resection and circumferential reconstruction was carried out. Results Both anterior and posterior procedures were successfully completed simultaneously in the sitting position in all cases. There were no perioperative complications. The average operative time was 175 ± 32 min (range, 120-240 min), and the mean blood loss was 430 ± 85 mL (range, 200-1100 mL). The patients were followed up for 35.8 months (range, 18-60 months). The symptom of neck pain improved distinctly and no evidence of implant failure was noted in any patients. Neurological status improvement was confirmed in six patients, who had suffered incomplete paralysis. The ASIA grade improved in five patients, and two cases had no change in grade. Conclusions The 'sitting position' simultaneously combined anterior-posterior approach is safe and is superior to the traditional prone position and supine position, and the surgical results are satisfactory. [ABSTRACT FROM AUTHOR]

The decomposition of nitramines explosives have been of great interest for a long time. However, theoretical investigations have concentrated mainly on unimolecular decomposition whereas bimolecular reactions have received only little attention. In this paper, the bimolecular reaction between NO2 with s-triazine (TAZ), which is an initial product during the decomposition process of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) is investigated. The structures and potential energy surface (PES) are explored at B3LYP/6-31G(d,p) and B3P86/6-31G(d,p) levels, and the energies are refined using the CCSD(T)/cc-pVTZ methods. The mechanism of the reaction is analyzed. Quantum chemistry calculations reveal that the title reactions possess small barriers that can be similar to, or smaller than that of initial decomposition reactions of RDX, which suggests that bimolecular reactions are also of great importance, and should be further investigated. Moreover, the kinetics were investigated to verify the proposed mechanism of the reaction. [ABSTRACT FROM AUTHOR]

Objective Japanese Orthopaedic Association ( JOA) scoring systems were developed to evaluate the neurological function of patients with cervical or lumbar degeneration. As patient-based and multi-dimensional clinical evaluation tools, these systems should be capable of reflecting the walking disability of patients. The association between JOA scores and gait parameters, however, are not well characterized. The purpose of this study was to determine the correlations between JOA scores and gait parameters of patients with cervical spondylotic myelopathy ( CSM) and lumbar intervertebral disc herniation ( LDH). Methods A total of 32 CSM and 30 LDH patients with gait dysfunction were recruited for the present study. All patients were diagnosed by two senior orthopaedic doctors and evaluated with JOA scoring systems. A body-mounted motion analyzer, the Intelligent Device for Energy Expenditure and Activity ( IDEEA), was applied to measure gait parameters of patients across 30 m of flat floor in an orthopaedic ward. A linear regression model was used to determine the correlations between JOA scores and gait parameters. Multiple linear regressions were used to identify the relationships between subsections of the JOA systems and gait parameters. Results Japanese Orthopaedic Association scores of LDH patients from the JOA lumbar scoring system are significantly correlated with gait speed ( R2 = 0.557, P < 0.001) and stride length ( R2 = 0.544, P < 0.001). JOA scores are also correlated with double support duration, step duration, cycle duration and cadence, and weakly correlated with single support duration. For the four subsections of the JOA lumbar scoring system, 'restriction of activities of daily living' is the significant predictor of all gait parameters, especially gait speed ( R2 = 0.573, P < 0.001) and stride length ( R2 = 0.553, P < 0.001). However, JOA scores of CSM patients from the JOA cervical scoring system are only weakly correlated with these measures (all R2 < 0.3). For the four subsections of the JOA cervical scoring system, 'motor function of the lower extremity' is a weak predictor of gait parameters (all R2 < 0.3). Conclusions There is a significant correlation between gait parameters and functional disability as measured by the JOA lumbar scoring system, which indicates that the JOA lumbar scoring system can reflect gait impairment. The JOA cervical scoring system, however, may need to be improved for efficiently evaluating the walking ability of CSM patients in the assessment of motor function of the lower extremity. [ABSTRACT FROM AUTHOR]

The purpose of this article is to introduce and analyze the feasibility of simultaneously combined anterior-posterior approaches for subaxial cervical circumferential reconstruction in sitting position. A retrospective case review was performed for above surgery procedure. A 79-year-old man was confirmed subaxial cervical fracture and dislocation with facet locked by radiological examination, and the involved levels were C5-6. According to American Spinal Injury Association ( ASIA) classification, the impairment scale was grade B. And the Subaxial Cervical Spine Injury and Severity Score (SLIC) were 9. The patient was restricted in sitting position with traction on a halo in extension to immobilize the head during the operation. A posterior laminectomy and pedicle screws insertion to the involved cervical spine was performed firstly. And then the anterior discectomy and strut graft were accomplished through an anterior cervical approach. The final fixation was finished by clamping the strut graft with pedicle screw system. Total blood loss was 600 ml and the total operating time was 150 min. The patient was followed up for 6 months. The symptom of neck pain improved distinctly and no evidence about implant failure was noted. Neurological status improvement was confirmed and the ASIA scale was improved to grade C. We believed that the simultaneously combined anterior-posterior approach in sitting position was safe and more advantageous for appropriate cases. [ABSTRACT FROM AUTHOR]

Objective To determine the features of discs in spinal cord injury without radiographic abnormality ( SCIWORA) by intraoperative disc contrast injection ( IODCI) and to subsequently treat the responsible discs operatively. Methods From January 2007 to December 2011, 16 adult cases of cervical SCIWORA were enrolled in this study. The average preoperative Japanese Orthopaedic Association ( JOA) score was 9.1 ± 1.8. Although preoperative imaging showed no obvious fracture or dislocation, spinal cord compression was evident in all cases. High spinal cord signals on MRI T2WI and cervical disc degeneration were present in all cases and swollen soft tissue anterior to the cervical spine in nine cases. All patients underwent anterior cervical surgeries for spinal cord compression, IODCI being performed after exposure of suspicious discs. Patients with only one ruptured disc underwent anterior cervical discectomy and fusion; those with more complex injuries underwent anterior cervical corpectomy and fusion with fixation of the ruptured segment. JOA scores, X-rays and CT scans were checked at specified intervals over an average of 24.4 months. Results Of 32 discs suspected preoperatively of being injured, 19 were identified as ruptured by IODCI. Anterior annulus fibrosus rupture was proved in 11 patients whereas the anterior longitudinal ligament was intact in all. JOA scores at 2 weeks, 3 months and last follow-up postoperatively were 13.3 ± 1.5, 14.5 ± 1.6 and 15.1 ± 1.5 respectively. The recovery rates were 53.2%, 68.3% and 75.9%, respectively. Conclusion IODCI helps to determine the segment responsible for cervical SCIWORA. [ABSTRACT FROM AUTHOR]

Objective To report three cases of transient paralysis shortly after (within 4 hours) anterior cervical corpectomy and fusion ( ACCF), and investigate the possible causes. Methods Clinical and radiological data of three cases (two men and one woman, aged 41-61 years) were analyzed retrospectively. All three patients underwent ACCF for cervical spondylotic myelopathy. The decompressed segments were located in C5, C6 and C5 + C6-7 discs, respectively. Paralysis occurred from 30 minutes to 4 hours after surgery. In two cases the paralysis was complete; it was incomplete in the third. All patients received immediate dehydration, neurotrophic drugs and high-dose methylprednisolone therapy upon recognition of their paralysis. Meanwhile, cervical MRIs were performed and showed no significant hematomas compressing the cervical spinal cord; spinal cord edema was clearly evident in all cases. Results In two cases the paralysis resolved within 2 hours of diagnosis and immediate medication. In the third case, because the neurological symptoms were incompletely resolved 24 hours after beginning medication, a second laminoplasty was performed. During decompression, tremendous pressure was released from the cervical spinal cord. The neurological symptoms had resolved completely by 1 week after decompression. Conclusion The precise cause for transient paralysis after these anterior cervical surgeries is not yet clear. Spinal cord ischemia-reperfusion injury is generally regarded as the most likely cause. Therefore, a combination of cervical spinal cord edema and limited anterior decompression space may have been the main contributing factors to the paralysis reported here. Early diagnosis and early intervention to relieve the paralysis can restore spinal cord function and result in a satisfactory prognosis. [ABSTRACT FROM AUTHOR]

Anterior lumbar interbody fusion (ALIF) has increased in popularity because it has advantages over posterior fusion. Because there is disagreement about the stability of stand-alone cage ALIF, some surgeons use various types of supplementary fixation, including anterior plates, pedicle screw systems and translaminar screws, to increase segmental stability. Many factors associated with both the cages and endplates influence the time of onset and extent of subsidence after use of stand-alone cage ALIF. A large round cage with an adequate central opening is recommended to facilitate maximum contact with the periphery of the endplate. With regard to the relationship between radiographic fusion and recurrence of symptoms with the development of subsidence, most researchers have reported finding no correlation. Subsidence may be due to a process of bone incorporation between cages and endplates. Does subsidence or nonfusion really matter clinically? Further prospective, randomized controlled trials are very much needed to answer these questions. [ABSTRACT FROM AUTHOR]

Vertebroplasty (VP) and kyphoplasty (KP) have been proven equally effective in providing pain relief in patients with vertebral compression fractures (VCF). Both have been reported to have multiple complications which, though rare, are potentially devastating. This literature review focuses on comparing the incidence of various types of complication of VP and KP. Local cement leakage and pulmonary cement embolism have been reported more commonly after VP than KP. It is questionable whether the relative risk of developing an adjacent level new fracture after VP is greater than after KP The relationship between a new VCF and each of these procedures has also not been clearly established. Although the majority of complications are clinically silent, their potential risks, which include a fatal outcome, should always be kept in mind by the practitioner. [ABSTRACT FROM AUTHOR]

In the title compound, C27H22N2O4, the two indole ring systems are approximately perpendicular to each other, with a dihedral angle of 84.5 (5)° between their planes; the benzene ring is twisted with respect to the two indole ring systems at angles of 78.5 (5) and 86.5 (3)°. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds, weak C-H⋯O and C-H⋯N hydrogen bonds, and C-H⋯π inter-actions into a three-dimensional supra-molecular architecture.

In the title compound, C(29)H(26)N(2)O(4), the benzene ring is twisted by 73.5 (5) and 84.9 (3)° with respect to the mean planes of the two indole ring systems; the mean planes of the indole ring systems are oriented at a dihedral angle of 82.0 (5)°. In the crystal, mol-ecules are linked by pairs of N-H⋯O hydrogen bonds into chains.

The title compound, C(8)H(9)N(3)S, contains two mol-ecules in the asymmetric unit. One mol-ecule is close to being planar (r.m.s. deviation from the mean plane = 0.06 Å for the non-H atoms), while the other exhibits a dihedral angle of 21.7 (1)° between the benzene ring and the mean plane of the thio-semicarbazone unit. Inter-molecular N-H⋯S hydrogen bonds link the mol-ecules into layers parallel to the (010) plane.

The title compound, C(12)H(10)ClNO(2), crystallizes with two independent mol-ecules in the asymmetric unit; these are approximate mirror images of each other. In each mol-ecule, the chloro-methyl and acetate groups lie on the same side of the quinoline ring system, with dihedral angles between the ring plane and the plane of the acetate group of 82.0 (1) and -79.2 (1)°. The C-C-C-Cl torsion angles for the chloro-methyl groups of the two mol-ecules are 80.9 (2) and -83.1 (2)°.