Short segmental pedicle screw fixation combined with percutaneous vertebroplasty in treatment of nonadjacent thoracolumbar fractures

ObjectiveTo evaluate the short-term outcomes of short segmental pedicle screw fixation combined with percutaneous vertebroplasty in treatment of nonadjacent thoracolumbar fractures.MethodsTwenty patients who suffered from nonadjacent thoracolumbar fractures were treated by short segmental pedicle screw fixation for burst fracture and by percutaneous vertebroplasty for compression fracture. X-rays, CT and MRI scans were conducted using the same protocol before and after surgery and during follow-up. Pre- and postoperative American Spinal Injury Association (ASIA) grades, fusion of fracture sites, visual analog scale (V AS) of back pain, and Oswestry disability index (ODI) were accessed.ResultsAll patients were followed up for an average period of 12 months. The sagittal profile of the thoracolumbar spine was restored satisfactorily. No patient had neurologic deterioration after surgery, and 9 patients with incomplete lesions improved postoperatively by at least one ASIA grade. The fusion rate was 100%. The average V AS of back pain was 7.6 preoperatively and 3.2 postoperatively. The average ODI was 72.5 preoperatively and 35.5 postoperatively.ConclusionsShort segmental pedicle screw fixation combined with percutaneous vertebroplasty in treatment of nonadjacent thoracolumbar fractures exhibits such advantages as preserving functional segment units, reliable fixation, good neurologic recovery and early mobilization and, therefore, is suitable for treating nonadjacent thoracolumbar fractures

N-{N-[N-(1,1-Dimethyl­ethoxy­carbon­yl)-l-leuc­yl]-N-methyl-l-leuc­yl}-N-methyl-l-leucine benzyl ester

The tripeptide title compound, C32H53N3O6, synthesized in 80% yield by coupling of N-methyl-l-leucine benzyl ester with tert-butoxy­carbonyl-l-leucyl-N-methyl-l-leucine at 273 K, conjugates through two amide linkages and includes two protecting groups: a tert-butyl­oxycarbonyl group at the C-tip and a benzyl group at the N-tip. A classical inter­molecular N—H⋯O hydrogen bond and a weak non-conventional inter­molecular C—H⋯O contact connect the mol­ecules, forming layers parallel to (001)

Cosmological constraints on holographic dark energy models under the energy conditions

We study the holographic and agegraphic dark energy models without interaction using the latest observational Hubble parameter data (OHD), the Union2.1 compilation of type Ia supernovae (SNIa), and the energy conditions. Scenarios of dark energy are distinguished by the cut-off of cosmic age, conformal time, and event horizon. The best-fit value of matter density for the three scenarios almost steadily located at $\Omega_{m0}=0.26$ by the joint constraint. For the agegraphic models, they can be recovered to the standard cosmological model when the constant $c$ which presents the fraction of dark energy approaches to infinity. Absence of upper limit of $c$ by the joint constraint demonstrates the recovery possibility. Using the fitted result, we also reconstruct the current equation of state of dark energy at different scenarios, respectively. Employing the model criteria $\chi^2_{\textrm{min}}/dof$, we find that conformal time model is the worst, but they can not be distinguished clearly. Comparing with the observational constraints, we find that SEC is fulfilled at redshift $0.2 \lesssim z \lesssim 0.3$ with $1\sigma$ confidence level. We also find that NEC gives a meaningful constraint for the event horizon cut-off model, especially compared with OHD only. We note that the energy condition maybe could play an important role in the interacting models because of different degeneracy between $\Omega_m$ and constant $c$.Comment: 8 pages, 4 figures, accepted for publication in PR

Posterior-only spinal fusion without rib head resection for treating type I neurofibromatosis with intra-canal rib head dislocation

OBJECTIVES: Patients with Type I neurofibromatosis scoliosis with intra-canal rib head protrusion are extremely rare. Current knowledge regarding the diagnosis and treatment for this situation are insufficient. The purpose of this study is to share our experience in the diagnosis and surgical treatments for such unique deformities. METHODS: Six patients with Type I neurofibromatosis scoliosis with rib head dislocation into the spinal canal were diagnosed at our institution. Posterior instrumentation and spinal fusion without intra-canal rib head resection via a posterior-only approach was performed for deformity correction and rib head extraction. The efficacy and outcomes of the surgery were evaluated by measurements before, immediately and 24 months after the surgery using the following parameters: coronal spinal Cobb angle, apex rotation and kyphosis of the spine and the intra-canal rib head position. Post-operative complications, surgery time and blood loss were also evaluated. RESULTS: Patients were followed up for at least 24 months post-operatively. The three dimensional spinal deformity was significantly improved and the intra-canal rib head was significantly extracted from the canal immediately after the surgery. At follow-up 24 months after surgery, solid fusions were achieved along the fusion segments, and the deformity corrections and rib head positions were well maintained. There were no surgery-related complications any time after the surgery. CONCLUSIONS: Systematic examinations are needed to identify patients with Type I neurofibromatosis scoliosis with rib head dislocation into the canal who can be treated by posterior-only spinal fusion without rib head resection

Evaluation of an enzyme-linked immunospot assay for the immunodiagnosis of atypical spinal tuberculosis (atypical clinical presentation/atypical radiographic presentation) in China

AbstractBackgroundAtypical spinal tuberculosis (TB) usually presents in a slowly indolent manner with nonspecific clinical presentations making the diagnosis a great challenge for physicians. New technologies for the detection of atypical spinal TB are urgently needed. The aim of this study was to assess the diagnostic value of an enzyme-linked immunospot (ELISPOT) assay in clinically suspected cases of atypical spinal TB in China.MethodsFrom March 2011 to September 2012, a total of 65 patients with suspected atypical spinal TB were enrolled. In addition to conventional tests for TB, we used ELISPOT assays to measure the IFN-γ response to ESAT-6 and CFP-10 in T-cells in samples of peripheral blood mononuclear cells. Patients with suspected atypical spinal TB were classified by diagnostic category. Data on clinical characteristics of the patients and conventional laboratory results were collected.ResultsOut of 65 patients, 4 were excluded from the study. 18 (29.5%) subjects had culture-confirmed TB, 11 (18.0%) subjects had probable TB, and the remaining 32 (52.5%) subjects did not have TB. Generally, the features of atypical spinal TB include the following aspects: (1) worm-eaten destruction of vertebral endplate; (2) destruction of centricity of the vertebral body or concentric collapse of vertebral body; (3) tuberculous abscess with no identifiable osseous lesion; (4) contiguous or skipped vertebral body destruction. 26 patients with atypical spinal TB had available biopsy or surgical specimens for histopathologic examination and 23 (88.5%) specimens had pathologic features consistent with TB infection. The sensitivities of the PPD skin test and ELISPOT assay for atypical spinal TB were 58.6% and 82.8%, and their specificities were 59.4% and 81.3%, respectively. Malnutrition and age were associated with ELISPOT positivity in atypical spinal TB patients.ConclusionsThe ELISPOT assay is a useful adjunct to current tests for diagnosis of atypical spinal TB