Age-related changes in cervical sagittal range of motion and alignment

Study Design Retrospective cohort study. Objective To compare sagittal cervical range of motion (ROM) and alignment in young versus middle-aged adults. Methods One hundred four asymptomatic adults were selected randomly out of 791 subjects who underwent lateral cervical radiographs in neutral, flexion, and extension positions. They were divided into two groups: young (age 20 to 29, 52 people) and middle-aged adults (age 50 to 59, 52 people). We determined the ROMs of upper cervical (occipital–C2 angle), midcervical (C2–C7 angle), and cervicothoracic spine (cervicosternal angle). We compared the alignment differences of the two groups by calculating the distances between C2 and C7 plumb lines, and C2 central-offset distance. Results In neutral position, there was no significant difference between young and middle-aged adults. However, in flexion, C2–C7 angle, distance between C2–C7 plumb lines, and C2 central-offset distance decreased with age. In extension, C2–C7 angle and C2 central-offset distance decreased with age. During flexion and extension, midcervical ROM and the range of C2 central-offset distance decreased in the middle-aged group. However, there was no difference between the two age groups in the ROM of the upper cervical and the cervicothoracic regions during flexion and extension. Conclusion We found that, despite of the presence of age-related cervical alignment changes, the only difference between the two groups was in the sagittal ROM of the midcervical spine during flexion and extension. Only the ROM of the midcervical spine appears to change significantly, consistent with findings that these levels are most likely to develop both symptomatic and asymptomatic degenerative changes

Radiographic comparison between cervical spine lateral and whole-spine lateral standing radiographs

Study Design Retrospective radiologic study. Objective The sagittal alignment of the cervical spine can be evaluated using either a lateral cervical radiograph or a whole-spine lateral view on which the cervical spine is included. To our knowledge, however, no report has compared the two. The purpose of this work is to identify the difference in radiographic parameters between the cervical spine lateral view and the whole-spine lateral view. Methods We retrospectively analyzed 59 adult patients suffering from neck pain with cervical spine lateral radiographs and whole-spine lateral radiographs from November 2007 to December 2011. The radiographs were measured using standard techniques to obtain the following parameters from the two different radiographs: occipital–C2 angle, C2–C7 angle, C7–sternal angle, sternal slope, T1 slope, C2 central offset distance, the distance between C2 and C7 plumb lines, C4 anteroposterior (AP) diameter, the ratio of C2 central off distance to C4 AP diameter, the ratio of plumb lines' distance to C4 AP diameter. Results We found that the occipital–C2 angle, sternal slope, and C4 AP diameter were similar, but the C2–C7 angle, C7–sternal angle, T1 slope, C2 central offset distance, distance between C2 and C7 plumb lines, ratio of C2 central off distance to C4 AP diameter, and ratio of plumb lines' distance to C4 AP diameter were different. However, the error of measurement was greater than the small angular and linear differences between the two views. Conclusions Most numerical values of the measured radiographic parameters appear to be different between the two views. However, the two views are comparable because the numerical differences were smaller than the errors of measurement

Delayed surgical intervention in central cord syndrome with cervical stenosis

Study Design Review of the literature. Objective It is generally accepted that surgical treatment is necessary for central cord syndrome (CCS) with an underlying cervical stenosis. However, the surgical timing for decompression is controversial in spondylotic cervical CCS. The purpose of this study is to review the results of early and delayed surgery in patients with spondylotic cervical CCS. Methods MEDLINE was searched for English-language articles on CCS. There were 1,653 articles from 1940 to 2012 regarding CCS, 5 of which dealt with the timing of surgery for spondylotic cervical CCS. Results All five reports regarding the surgical timing of spondylotic cervical CCS were retrospective. Motor improvement, functional independence measures, and walking ability showed similar improvement in early and late surgery groups in the studies with follow-up longer than 1 year. However, greater improvement was seen in the early surgery group in the studies with follow-up shorter than 1 year. The complication rates did not show a difference between the early and late surgery groups. However, there are controversies regarding the length of intensive care unit stay or hospital stay for the two groups. Conclusions There was no difference in motor improvement, functional independence, walking ability, and complication rates between early and late surgery for spondylotic cervical CCS

Asymptomatic stenosis in the cervical and thoracic spines of patients with symptomatic lumbar stenosis

Study Design Retrospective study. Objective Studies on age-related degenerative changes causing concurrent stenoses in the cervical, thoracic, and lumbar spines (triple stenosis) are rare in the literature. Our objectives were to determine: (1) the incidence of asymptomatic radiologic cervical and thoracic stenosis in elderly patients with symptomatic lumbar stenosis, (2) the incidence of concurrent radiologic spinal stenosis in the cervical and thoracic spines, and (3) the radiologic features of cervical stenosis that might predict concurrent thoracic stenosis. Methods Whole-spine T2 sagittal magnetic resonance images of patients older than 80 and diagnosed with lumbar spinal stenosis between January 2003 and January 2012 were evaluated retrospectively. We included patients with asymptomatic spondylotic cervical and thoracic stenosis. We measured the anteroposterior diameters of the vertebral body, bony spinal canal, and spinal cord, along with the Pavlov ratio and anterior or posterior epidural stenosis at the level of the disk for each cervical and thoracic level. We compared the radiologic parameters between the subgroups of cervical stenosis with and without thoracic stenosis. Results Among the 460 patients with lumbar stenosis, 110 (23.9%) had concurrent radiologic cervical stenosis and 112 (24.3%) had concurrent radiologic thoracic stenosis. Fifty-six patients (12.1%) had combined radiologic cervical and thoracic stenosis in addition to their symptomatic lumbar stenosis (triple stenosis). Anterior epidural stenosis at C7–T1 was associated with a high prevalence of thoracic stenosis. Conclusions It appears that asymptomatic radiologic cervical and thoracic stenosis is common in elderly patients with symptomatic lumbar stenosis

Surgical anatomy of the uncinate process and transverse foramen determined by computer tomography

Study Design Computed tomography–based cohort study. Objective Although there are publications concerning the relationship between the vertebral artery and uncinate process, there is no practical guide detailing the dimensions of this region to use during decompression of the intervertebral foramen. The purpose of this study is to determine the anatomic parameters that can be used as a guide for thorough decompression of the intervertebral foramen. Methods Fifty-one patients with three-dimensional computed tomography scans of the cervical spine from 2003 to 2012 were included. On axial views, we measured the distance from the midline to the medial and lateral cortices of the pedicle bilaterally from C3 to C7. On coronal reconstructed views, we measured the minimum height of the uncinate process from the cranial cortex of the pedicle adjacent to the posterior cortex of vertebral body and the maximal height of the uncinate process from the cranial cortex of the pedicle at the midportion of the vertebral body bilaterally from C3 to C7. Results The mean distances from midline to the medial and lateral cortices of the pedicle were 10.1 ± 1.3 mm and 13.9 ± 1.5 mm, respectively. The mean minimum height of the uncinate process from the cranial cortex of the pedicle was 4.6 ± 1.6 mm and the mean maximal height was 6.1 ± 1.7 mm. Conclusions Our results suggest that in most cases, one can thoroughly decompress the intervertebral foramen by removing the uncinate out to 13 mm laterally from the midline and 4 mm above the pedicle without violating the transverse foramen

Interfacial chemical bonding-mediated ionic resistive switching.

In this paper, we present a unique resistive switching (RS) mechanism study of Pt/TiO2/Pt cell, one of the most widely studied RS system, by focusing on the role of interfacial bonding at the active TiO2-Pt interface, as opposed to a physico-chemical change within the RS film. This study was enabled by the use of a non-conventional scanning probe-based setup. The nanoscale cell is formed by bringing a Pt/TiO2-coated atomic force microscope tip into contact with a flat substrate coated with Pt. The study reveals that electrical resistance and interfacial bonding status are highly coupled together. An oxygen-mediated chemical bonding at the active interface between TiO2 and Pt is a necessary condition for a non-polar low-resistance state, and a reset switching process disconnects the chemical bonding. Bipolar switching mode did not involve the chemical bonding. The nature of chemical bonding at the TiO2-metal interface is further studied by density functional theory calculations

Comparison of Surgical Outcomes in Thoracolumbar Fractures Operated with Posterior Constructs Having Varying Fixation Length with Selective Anterior Fusion

PURPOSE: Surgical treatment in the case of thoracolumbar burst fractures is very controversial. Posterior instrumentation is most frequently used, however, but the number of levels to be instrumented still remains a matter of debate. MATERIALS AND METHODS: A total of 94 patients who had a single burst fracture between T11 and L2 were selected and were managed using posterior instrumentation with anterior fusion when necessary. They were divided into three groups as follows; Group I (n = 28) included patients who were operated by intermediate segment fixation, Group II (n = 32) included patients operated by long segment fixation, and Group III (n = 34) included those operated by intermediate segment fixation with a pair of additional screws in the fractured vertebra. The mean follow-up period was twenty one months. The outcomes were analyzed in terms of kyphosis angle (KA), regional kyphosis angle (RA), sagittal index (SI), anterior height compression rate, Frankel classification, and Oswestry Disability Index questionnaire. RESULTS: In Groups II and III, the correction values of KA, RA, and SI were much better than in Group I. At the final follow up, the correction values of KA (6.3 and 12.1, respectively) and SI (6.2 and 12.0, respectively) were in Groups II and III found to be better in the latter. CONCLUSION: The intermediate segment fixation with an additional pair of screws at the fracture level vertebra gives results that are comparable or even better than long segment fixation and gives an advantage of preserving an extra mobile segment.ope

Efficacy of Antibiotics Sprayed into Surgical Site for Prevention of the Contamination in the Spinal Surgery

Study DesignRetrospective study.PurposeTo evaluate the effect of intraoperative wound application of vancomycin on preventing surgical wound contamination during instrumented lumbar spinal surgery.Overview of LiteraturePostoperative infection is the one of the most devastating complications of lumbar surgery. There are a few reports showing the benefits of intraoperative wound application of vancomycin during spinal surgery. However, there is no report about the effectiveness of local vancomycin instillation in prevention of surgical wound contamination.MethodsEighty-six patients underwent instrumented lumbar spinal surgery. Mean patient age was 65.19 years (range, 23-83 years). There were 67 females and 19 males. During surgery, vancomycin powder was applied into the surgical site before closure in 43 patients (antibiotic group) and vancomycin powder was not applied into the surgical site before closure in 43 patients (control group). The tip of the surgical drain was cultured to evaluate surgical wound contamination. Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were measured on the first, third, seventh, and fourteenth day after the operation.ResultsWe found two patients with a positive culture from the tip of surgical drains in the antibiotic group, and one patient with a positive culture from the tip of the surgical drain in the control group. Postoperative ESR and CRP levels did not show significant differences between the two groups. On the third postoperative day, ESR in patients of the antibiotic group was more significantly decreased than that in patients of the control group, while CRP level did not show a significant difference between the two groups.ConclusionsThere was no evidence to suggest that intraoperative vancomycin application is effective in decreasing the risk of postoperative wound infection after instrumented posterior lumbar fusion surgery

New Radiographic Index for Occipito-Cervical Instability

Study DesignRetrospective study.PurposeTo propose a new radiographic index for occipito-cervical instability.Overview of LiteratureSymptomatic atlanto-occipital instability requires the fusion of the atlanto-occipital joint. However, measurements of occipito-cervical translation using the Wiesel-Rothman technique, Power's ratio, and basion-axial interval are unreliable because the radiologic landmarks in the occipito-cervical junction lack clarity in radiography.MethodsOne hundred four asymptomatic subjects were evaluated with lateral cervical radiographs in neutral, flexion and extension. They were stratified by age and included 52 young (20–29 years) and 52 middle-aged adults (50–59 years). The four radiographic reference points were posterior edge of hard palate (hard palate), posteroinferior corner of the most posterior upper molar tooth (molar), posteroinferior corner of the C1 anterior ring (posterior C1), and posteroinferior corner of the C2 vertebral body (posterior C2). The distance from posterior C1 and posterior C2 to the above anatomical landmarks was measured to calculate the range of motion (ROM) on dynamic radiographs. To determine the difference between the two age groups, unpaired t-tests were used. The statistical significance level was set at p<0.05.ResultsThe ROM was 4.8±7.3 mm between the hard palate and the posterior C1, 9.9±10.2 mm between the hard palate and the posterior C2, 1.7±7.2 mm between the molar to the posterior C1, and 10.4±12.1 mm between the molar to the posterior C2. There was no statistically significant difference for the ROM between the young- and the middle-aged groups. The intra-observer reliability for new radiographic index was good. The inter-observer reliability for the ROM measured by the hard palate was low, but was better than that by the molar.ConclusionsROM measured by the hard palate might be a useful new radiographic index in cases of occipito-cervical instability