Disc Space Level Research Articles

Vascular injury risk stratification for lateral lumbar interbody fusion (LLIF) at L4-L5: a morphometric study using magnetic resonance imaging.

Proper vascular injury risk stratification (VIRS) methods for L4-L5 lateral lumbar interbody fusion (LLIF) surgery have not been well-described. The objective of this study was to propose a novel VIRS method for L4-L5 LLIF surgery via the transpsoas approach. Axial magnetic resonance imaging (MRI) of adult patients were obtained and analyzed. The VIRS scores were assessed using anterior disc line to posterior vessel wall distance, the disc vessel angle (DVA), and the disc edge to vessel distance at the level of L4-L5 disc space. Ninety-one consecutive adult patients were included in the study. The right common iliac vein (CIV) had a high risk of injury with both right- and left-sided approaches. The left CIV had a moderate risk with a left-sided approach when the iliocaval confluence was above the L4-L5 disc space but had a high risk when the confluence was at the L4-L5 disc space. The left CIV had a high risk with a right-sided approach when the confluence was above the L4-L5 disc space but had a moderate risk when the confluence was at the L4-L5 disc space. The inferior vena cava (IVC) had a high risk with both right- and left-sided approaches. The aorta had a moderate risk regardless of the right or left-sided approaches. The left common iliac artery (CIA) had a moderate risk with a right-sided approach and a low risk with a left-sided approach. The right CIA had a low risk with both right- and left-sided approaches. There are significant vascular anatomic variations at the L4-L5 disc level and a proper VIRS can be performed utilizing a combination of anterior disc line to posterior vessel wall distance, DVA, and disc edge to vessel distance, on the axial MRI.

What Is the Ideal Entry Point for Transforaminal Endoscopic Lumbar Discectomy?

ObjectiveThe method of approach during transforaminal endoscopic lumbar discectomy (TELD) has been the subject of repeated study. However, the ideal entry point during TELD has not been studied in detail. Therefore, this study investigated the ideal entry point for avoiding complications using computed tomography (CT) scans obtained from patients in the prone position. MethodsUsing CT scans obtained from patients in the prone position, we checked for retroperitoneal or visceral violations and measured the angles of approach with five conventional approach lines drawn on axial CT scans at each disc space level (L2–3, L3–4, and L4–5). We also determined the ideal entry point distance and approach angles for avoiding retroperitoneal or visceral violations. Correlation analysis was performed to identify the patient characteristics related to the ideal entry point properties. ResultsWe found that the far lateral approach at the L2–3 level resulted in high rates of visceral violation. However, rates of visceral violation at the L3–4 and L4–5 levels were remarkably low or absent. The ideal angles of approach decreased moving caudally along the spine, and the ideal entry point distances increased moving caudally along the spine. Weight, body mass index (BMI), and the depth of the posterior vertebral line from the skin were positively associated with the distance of the ideal entry point from the midline. ConclusionWe reviewed the risk of the extreme lateral approach by analyzing rates of retroperitoneal and visceral violations during well-known methods of approach. We suggested an ideal entry point at each level of the lumbar spine and found a positive correlation between the distance of the entry point to the midline and patient characteristics such as BMI, weight, and the depth of the posterior vertebral line from the skin.

Is intercrestal line and level of spine are same clinically and radiologically

Background: The line joining the iliac crest superiorly and posteriorly is known as Intercrestal line. Various studies described that it crosses in the midline at L4–L5 intervertebral disc space level. Relationship of spinal level on palpation and imaging the iliac crest intercrestal line is not the same in particular the L4–L5 interspace.Purpose: The purpose of this study is to compare the spinal level identified through palpation and imaging the iliac crest intercrestal line in adults.Materials and Methods: Patients included low back pain undergoing epidural steroid injection at RL Jalappa Hospital and Research Center, between October 2018 to January 2019. Iliac crest posterio-superiorly was palpated by the authors and the intercrestal line was drawn, then followed by imaging, the level of the spine in the midline identified and were recorded and compared.Results: Our study shows that on palpation the L3-4 spinal level in 27 patients (48.2%) and L4 spinal level in 22 patients (39.2%) whereas on imaging the L4 spinal level in 33 patients (58.9%) and L4–5 spinal levels in 21 patients (37.5%), the intercrestal line formed through palpation tended to identify higher levels. On both methods the same level observed in 10.7% (6 patients) only.Conclusion: Palpation and imaging method of iliac crest intercrestal line are the two methods to identify the spinal level. Clinically, the palpation of the intercrestal line to identify the L3–4 and L4 spinal levels rather than the L4 or L4–5 levels, particularly in patients with high BMI (body mass indices).

Factors for the acquisition of 10° angular change at the lumbar spine through posterior column osteotomy in adult spinal deformity surgery.

OBJECTIVEPosterior column osteotomy (PCO) has been known to provide an angular change (AC) of approximately 10° in sagittal plane deformity. However, whether PCO can actually obtain an AC of ≥ 10° depending on the particular level in the lumbar spine and which factors can effect a gain of ≥ 10° AC after PCO remain to be elucidated. The aim of this study was to identify the factors that effect a gain of ≥ 10° AC through PCO by comparing radiographic measurements between an AC group and a control group before and after adult spinal deformity (ASD) surgery.METHODSForty consecutive patients who underwent multilevel PCOs for ASD at a single institution between 2012 and 2016 were included in this study. PCO was performed in 142 disc space levels in the lumbar spine. The authors defined the disc space level that obtained ≥ 10° AC in the sagittal plane by PCO as the AC group and the remaining patients as controls. The modified Pfirrmann grade, surgical level, implementation of the transforaminal lumbar interbody fusion (TLIF), and radiographic measurements were compared between the groups.RESULTSThere were 67 levels in the AC group and 75 in the control group. Multivariate analysis identified the surgical level at L4-5 (OR 3.802, 95% CI 1.127-12.827, p = 0.031), performing TLIF with PCO (OR 3.303, 95% CI 1.258-8.674, p = 0.015), and a preoperative kyphotic disc space angle (OR 1.397, 95% CI 1.231-1.585, p < 0.001) as the factors that significantly effected ≥ 10° AC in the sagittal plane after PCO.CONCLUSIONSIn ASD surgery, PCO cannot always achieve ≥ 10° AC in the sagittal plane. The factors that effected ≥ 10° AC in PCO for ASD were surgical level at L4-5, performing TLIF with PCO, and the preoperative kyphotic disc space angle.

Hollow modular anchorage (HMA) screws for anterior transvertebral fixation in high-grade spondylolisthesis cases requiring 360 degrees in-situ fusion

Objective: 360 degrees in-situ fusion for high-grade spondylolisthesis showed satisfying clinical long-term results. Combining anterior with posterior surgery increases fusion rates. Anteriorly inserted transvertebral HMA screws could be an alternative to strut graft constructs or cages, avoiding donor site complications. In addition, complete posterior muscle detachment is avoided and the injury risk of neural structures is minimized. This study investigates the use of HMA screws in this context.Material and methods: Five consecutive patients requiring L4-S1 in-situ fusion for isthmic spondylolisthesis (four Grade 3 and one Grade 4) were included. The L5/S1 level was fused with an HMA screw filled with local bone and bone morphogenic protein (BMP2), inserted via the L4/5 disc space level. An L4/5 stand-alone interbody fusion with additional minimal invasive posterior screw fixation was added.Results: Transvertebral insertion of the HMA device was accomplished via a retroperitoneal approach to L4/L5 in all cases without exposure of L5/S1. Blood loss ranged from 150 ml–350 ml. No intraoperative complication occurred. One patient developed posterior wound infection requiring debridement. Solid fusion was confirmed with a CT scan after 6 months in all patients. All patients improved to unrestricted activities of daily living with two being limited by occasional back pain.Conclusions: HMA screws allow for effective lumbosacral fusion via a limited anterior exposure. This is technically easier than posterior exposure of the lumbosacral junction in high-grade spondylolisthesis requiring 360 degrees fusion.

Novel vertebral computed tomography indices in normal and spinal disorder dogs.

This study was carried out to derive and evaluate reference computed tomography (CT)-based indices for normal canine spine. CT and magnetic resonance images were acquired from 12 clinically normal Beagle dogs (normal group) and 50 dogs with 56 spinal disorders (patient group). Image acquisition regions were cervical spine (C2–T1), thoracic spine (T1–T13), and lumbar spine (L1–L7). Measured indices were: the ratios of width to height of the spinal cord including the dura matter (CR) and of the vertebral foramen (FR), and the ratio of the cross-sectional area of the spinal cord to that of the vertebral foramen (CFAR). Reliability analysis was performed to evaluate intermodality agreement. Student's t-tests and receiver operating characteristic curves were used to discriminate the normal and patient groups on CT. Intermodality agreements of the normal and patient groups were acceptable to excellent. The highest discriminating levels of CR at the vertebral body level and the intervertebral disc space level were 1.25 or more and 1.44 or more, respectively. FR and CFAR had the highest discriminating level at the cervical region. This report presents quantitative information on canine spinal morphometry; the obtained indices may be helpful for CT screening of dogs with spinal disorders.

Cervical Lordosis Actually Increases With Aging and Progressive Degeneration in Spinal Deformity Patients

Study DesignRetrospective. ObjectivesThe authors hypothesized that cervical lordosis (CL) would decrease with aging and increasing degeneration. Summary of Background DataIt is theorized that with age and degeneration, the cervical spine loses lordosis and becomes progressively more kyphotic; however, no studies support these conclusions in patients with various spinal deformities. MethodsThe authors performed a radiographic analysis of asymptomatic adults (referring to their cervical spine) of varying ages, with differing forms of spinal deformity to the thoracic/lumbar spine to see how cervical lordosis changes with increasing age. A total of 104 total spine EOS X-rays of adult (aged >18 years) spinal deformity patients without documented neck pain, prior neck surgery, or cervical deformity were reviewed. The researchers only reviewed EOS X-rays because they allow complete visualization from occiput to feet. Cervical lordosis, standard Cobb measurements, sagittal balance parameters, and cervical degeneration were quantified radiographically by the method previously described by Gore et al. Statistical analysis was performed with 1-way analysis of variance to compare significant differences between groups aged <40, 40–60 and >60 years as well as changes in sagittal balance. A p-value < .05 was considered significant. ResultsAverage CL actually increased with increasing age (10.3 ± 14.7, 15.4 ± 15.1, and 23.3 ± 1.6.7 for age < 40, 40–60, and > 60 years, respectively; p < .05). Average cervical degeneration score increased at all disc space levels from C2 to C7 across age groups (0.7 ± 1.2, 9.9 ± 69, and 16.3 ± 8.9 for age <40, 40–60, and >60 years, respectively; p < .01), with the highest degeneration at the C5–6 and C6–7 disc spaces (3.7 ± 3.3 and 3.2 ± 2.9, respectively; p < .01). This increase did not correlate with the increase in CL seen with aging (r = 0.02; p = .84). ConclusionsCervical lordosis increased with aging in adult spinal deformity patients. There was no relationship between cervical degeneration and lordosis despite the strong relationship seen between increasing CL in older age groups.

Computed tomography-defined abdominal adiposity is associated with acute kidney injury in critically ill trauma patients*.

Higher body mass index is associated with increased risk of acute kidney injury after major trauma. Since body mass index is nonspecific, reflecting lean, fluid, and adipose mass, we evaluated the use of CT to determine if abdominal adiposity underlies the body mass index-acute kidney injury association. Prospective cohort study. Level I Trauma Center of a university hospital. Patients older than 13 years with an Injury Severity Score greater than or equal to 16 admitted to the trauma ICU were followed for development of acute kidney injury over 5 days. Those with isolated severe head injury or on chronic dialysis were excluded. None. Clinical, anthropometric, and demographic variables were collected prospectively. CT images at the level of the L4-5 intervertebral disc space were extracted from the medical record and used by two operators to quantitate visceral adipose tissue and subcutaneous adipose tissue areas. Acute kidney injury was defined by Acute Kidney Injury Network creatinine and dialysis criteria. Of 400 subjects, 327 (81.8%) had CT scans suitable for analysis: 264 of 285 (92.6%) blunt trauma subjects and 63 of 115 (54.8%) penetrating trauma subjects. Visceral adipose tissue and subcutaneous adipose tissue areas were highly correlated between operators (intraclass correlation > 0.99, p < 0.001 for each) and within operator (intraclass correlation > 0.99, p < 0.001 for each). In multivariable analysis, the standardized risk of acute kidney injury was 15.1% (95% CI, 10.6-19.6%), 18.1% (14-22.2%), and 23.1% (18.3-27.9%) at the 25th, 50th, and 75th percentiles of visceral adipose tissue area, respectively (p = 0.001), with similar findings when using subcutaneous adipose tissue area as the adiposity measure. Quantitation of abdominal adiposity using CT scans obtained for clinical reasons is feasible and highly reliable in critically ill trauma patients. Abdominal adiposity is independently associated with acute kidney injury in this population, confirming that excess adipose tissue contributes to the body mass index-acute kidney injury association. Further studies of the potential mechanisms linking adiposity with acute kidney injury are warranted.

MR imaging quantitative analysis of fetal chiari II malformations and associated open neural tube defects: Balanced SSFP versus half‐fourier RARE and interobserver reliability

To evaluate bSSFP (balanced steady state free precession) and half-Fourier RARE (rapid acceleration with relaxation enhancement) MRI sequences in their ability to demonstrate fetal anatomic landmarks, quantify the degree of cerebellar herniation in Chiari II malformations and level and length of the associated open neural tube defects, as well as evaluate interobserver reliability of these measurements. Two independent observers retrospectively reviewed MRIs of 37 fetuses with Chiari II malformations and associated open neural tube defects (mean gestational age: 27 weeks 2 days). Comparison of bSSFP and RARE included: (i) Ability to confidently identify anatomic landmarks of the posterior fossa and spine; (ii) Measurements of the foramen magnum, cerebellar tonsillar herniation length, intervertebral disc space level of tonsillar herniation, open neural tube defect length, and disc space start and end level of the open neural tube defect; (iii) Observed conspicuity of anatomic landmarks. There was no significant difference in assessment of cerebellar tonsillar herniation or open neural tube defect level between bSSFP and RARE for either observer. Intervertebral discs were more conspicuous on bSSFP while cerebellar tonsils were more conspicuous on RARE (P < 0.05). Interobserver reliability was strong for both sequences in assessing the foramen magnum (r = 0.95, 0.94), tonsillar herniation length (r = 0.93, 0.95), and open neural tube defect length (r = 0.97, 0.96). Despite improved conspicuity of the intervertebral discs with bSSFP and cerebellar tonsils with RARE, there is no significant difference in measurement of hindbrain herniation or open neural tube defect level; interobserver reliability is excellent for both sequences.

Posterior Osteophyte Evolution and its Impact in Cervical Spondylosis: A Literature Review

Abstract Introduction: In cervical disc disease, the exact location of the posterior osteophyte with relationship to the bodies of the adjacent cervical vertebra at each disc space level, as observed during surgery under operating microscope and correlating it with the histopathological development of the posterior osteophyte has not been documented in literature. A detailed review of literature on the development of posterior osteophytes and its impact on cervical spinal cord is also being reviewed. Materials and Methods: 1st Phase: In a prospective study conducted over first 5 years (2007-2012), intraoperative observations of 294 disc spaces in 201 patients who were operated for cervical disc disease using the standard anterior cervical microdiscectomy were analyzed. We observed under operating microscope 32 C3-C4 disc spaces, 62 C4-C5, 123 C5- C6, 74 C6-C7, 2 C7- D1 and 1 C2- C3 disc space during the study period. 2nd Phase: The above prospective study was extended into the 2nd phase over next 3 1/2 years (2009-2012), and clinico-radiological (MRI findings) - intraoperative observations of 118 disc spaces in 70 patients who were operated for cervical disc disease were analyzed. These observations were correlated with the histopathological characteristics of the excised disc material. Results: 1st Phase study: At C3-C4 disc space, posterior osteophyte originates from the upper vertebral body of C3 in 78.13% [25/32] disc spaces. In mobile segments of C4-C5 in 70.96% [44/62] and C5-C6 in 84.55% [104/123] disc spaces, the osteophyte arises from posterior margins of both the vertebral bodies. At C6 –C7, it arises from lower vertebral body of C7 in 71.62% [53/74]) disc spaces. 2nd Phase: It was observed histopathologically and intraoperatively, that posterior osteophytes formation goes through three stages. Posterior osteophyte formation is of Fibrocartilage in 10.17% (12/118), Mixed variety 7.62% (9/118) and Bony type in 82.20% [97/118]. In patients who had Bony type, 89.4% had myelopathy, 75 % had radiculopathy while 89.4% patients had hyperintense signal within the spinal cord. Discussion: Our results show that there is a definite pattern in the formation of the posterior osteophyte within the cervical disc spaces. At junctional areas like C3-C4 and C6 –C7 the posterior osteophyte originates from the relatively fixed vertebra like C3 and C7. In mobile segments like C4-C5 and C5- C6 the posterior osteophyte originates from both the bodies of adjacent vertebra. We also observed that the posterior osteophyte formation in cervical disc disease goes through the following three stages. 1st stage: Fibrocartilage, 2nd stage: Mixed type consisting of both the fibrocartilage and partially bony and 3rd stage: Bony type. These stages we feel evolve over a span of few years. Patients presenting with myeloradiculopathy and hyperintense signal within the spinal cord are likely to harbor bony posterior osteophytes compressing the thecal sac and requires surgical intervention. This is the first document of its kind in literature. Detailed reviews of literature on experimental models showing the development of posterior osteophyte supporting our observations, the pathological and radiological impact of the posterior osteophytes on cervical spinal cord, natural history of cervical spondylotic myelopathy and fate of the posterior osteophytes after anterior fusion surgery are being dealt upon in this paper.

Does it need to perform anterior column support after Smith-Petersen osteotomy for ankylosing spondylitis?

PurposeThe aim of this study was to determine whether anterior column support is required in Smith-Petersen osteotomy procedure with correction angles of more than 10°, while examining the subsequent healing patterns in relation to the disrupted area.MethodsAn analysis was done on 26 segments of 19 patients who showed a correction angle of more than 10° in the anterior opening after SPO. There were 17 male and two female patients with a mean age of 40 years (24–56 years). The mean follow-up period was 6.5 years (2–9.1 years). The patients were classified according to the site of the anterior opening, as the disc level, the lower end-plate of the upper body (upper body), or the upper end-plate of the lower body (lower body). The healing patterns of anterior opening and the radiological correction angles were evaluated relative to the opening site.ResultsIn all cases, bony fusion was confirmed at a mean period of 5.6 months (3–6.7 months) after surgery and the anterior opening gap was healed in 18 segments (69.2%). For patients that developed an opening in the upper body, all of the gaps were healed. The gaps in the lower body opening group were healed in 85.7% of the cases, and for the opening at the disc level, the gaps were healed only in 12.5% of the cases. The least amount of correction was obtained when anterior opening occurred in disc level.ConclusionsIn our study of subjects presenting with anterior opening angles from 10° to 32°, we obtained successful fusion without the need for additional anterior interbody fusion. Improved gap healing and increased correction angles were obtained when the opening was present in the upper or lower body endplates compared to those at the disc space level.

Chronic, Progressive Back Pain, Fever and a Noticeable Paravertebral Mass

A 46-year-old woman presented with an 8-month history of fever, lumbar pain, and a slowly growing right paravertebral mass. She reported regular consumption of unpasteurized goat cheese. The physical examination revealed a fluctuant right paravertebral mass and marked pain on palpation over the lumbar spine at the L3-L4 level. A computed tomography (CT) scan of the spine revealed erosions of the end plates of L3 and L4 and the antero-superior angle of L3, narrowing of the intervertebral space between L3 and L4, and new bone formation (Figure 1). Widening of the right iliopsoas muscle was also observed on magnetic resonance imaging (MRI) of the spine (Figure 2). A tube agglutination test for brucellosis was positive at 1/640, and a CT-guided percutaneous drainage of the paravertebral mass yielded purulent material from which Brucella melitensis was isolated in culture. Doxycycline, gentamycin, and rifampicin were started with good clinical response. Bacterial vertebral osteomyelitis may be caused by pyogenic bacteria, Mycobacterium tuberculosis, and B. melitensis. Tuberculosis predominantly affects the thoracic spine; paravertebral masses are common, but new bone formation is unusual. Pyogenic vertebral osteomyelitis, mainly caused by Staphylococcus aureus, presents very similarly to brucellosis both clinically and radiographically. Brucellosis caused by B. melitensis is acquired mostly by eating contaminated dairy products. Vertebral osteomyelitis and iliopsoas abscess are recognized complications of untreated brucellosis.1 Triple antibiotic therapy seems to improve clinical outcome.2 Figure 1. (A) CT scan of the spine showing erosions on the antero-superior angle of the vertebral body of L3, narrowing of the intervertebral disc space between L3 and L4, erosions on the end plates of these two vertebral bodies, and new bone formation. (B) Widening ... Figure 2. (A) MRI of the spine. Hypointensity on T1-weighted images at the L3-L4 level and narrowing of the L3-L4 intervertebral disc space. (B) Hyperintesity on T2-weighted images and marked widening of the right iliopsoas muscle.

Quantitative analysis of the anterolateral ossification mass in diffuse idiopathic skeletal hyperostosis of the thoracic spine

Diffuse idiopathic skeletal hyperostosis (DISH) is a systemic condition leading to ossification of spinal ligaments and has been shown to behave similarly to ankylosing spondylitis (AS) often leading to unstable hyperextension fractures. Currently, no quantitative data are available on the spatial relationship between the bridging anterolateral ossification mass (ALOM) and the vertebral body/intervertebral disc to explain the propensity in DISH to fracture through the vertebral body instead of through the intervertebral disc as more often seen in AS. Furthermore, no reasonable explanation is available for the typical flowing wax morphology observed in DISH. In the current study, a quantitative analysis of computed tomography (CT) data from human cadaveric specimens with DISH was performed to better understand the newly formed osseous structures and fracture biomechanics. Additionally, the results were verified using computed tomography angiography data from ten patients with DISH and ten controls. Transverse CT images were analyzed to obtain ALOM area and centroid angle relative to the anteroposterior axis; intervertebral disc and adjacent cranial and caudal levels. The ALOM area at the mid-vertebral body level averaged 57.9 ± 50.0 mm2; at the mid-intervertebral disc space level it averaged 246.4 ± 95.9 mm2. The mean ALOM area at the adjacent level caudal to the mid-vertebral body level was 169.6 ± 81.3 mm2; at the adjacent cranial level, it was 161.7 ± 78.2 mm2. The main finding was the significant difference between mean ALOM area at the mid-vertebral body level and other three levels (p < 0.0001). The subsequent verification study showed the presence of vertebral segmental arteries at the mid-vertebral body level in nearly all images irrespective of the presence of DISH. A larger area of ALOM seemed associated with increased counter-clockwise rotation (away from the aorta) of the centroid relative to the anteroposterior axis. The results from the present study suggest a predisposition for fractures through the vertebral body and a role for the arterial system in the inhibition of soft tissue ossification.

Borderline low conus medullaris on infant lumbar sonography: what is the clinical outcome and the role of neuroimaging follow-up?

Isolated borderline low conus medullaris is a frequent finding on screening lumbar sonography of unknown significance that often prompts further imaging and clinical follow-up. To determine the clinical outcome and utility of follow-up neuroimaging in infants with isolated borderline low conus on lumbar sonography. We reviewed 748 consecutive spinal sonograms identifying infants with conus terminating between L2-L3 disc space and mid-L3 level without other findings of tethered cord. We excluded infants with conditions associated with developmental delay and those who passed away, and compared the age of gross motor milestone achievement to normal ranges. Follow-up imaging was reviewed. Isolated borderline low conus was found in 90 of 748 infants (12%) on sonography. Seventy of those infants met inclusion criteria. Follow-up imaging in 11 children (10 MRI, 1 sonogram), showed change in conus position to "normal" level in 10, no change in 1, and no new findings within lumbar spine. Clinical follow-up was available in 50 of 70 (71%) children meeting inclusion criteria, with normal motor milestones met in all 50 children. Isolated borderline low conus is a common finding in infants who meet normal developmental milestones suggesting that follow-up evaluation has little utility and is likely unwarranted.

Capillary Hemangioma of the Thoracic Spinal Cord

Capillary hemangiomas are common soft tissue tumors on the skin or mucosa of the head and neck in the early childhood, but very rare in the neuraxis. A 47-year-old man presented with one month history of back pain on the lower thoracic area, radiating pain to both legs, and hypesthesia below T7 dermatome. Thoracic spine MRI showed 1×1.3×1.5 cm, well-defined intradural mass at T6-7 disc space level, which showed isointensity to spinal cord on T1, heterogeneous isointensity on T2-weighted images, and homogeneous strong enhancement. The patient underwent T6-7 total laminotomy, complete tumor removal and laminoplasty. Histologically, the mass showed a capsulated nodular lesion composed of capillary-sized vascular channels, which were tightly packed into nodules separated by fibrous septa. These features were consistent with capillary hemangioma.

Disc displacement patterns in lumbar anterior spondylolisthesis: Contribution to foraminal stenosis

Purpose To describe the particular disc displacement pattern seen at MRI in patients with spondylolisthesis, and its potential contribution to foraminal stenosis. Methods 38 patients with symptomatic lumbar anterior spondylolisthesis and 38 sex and aged matched control patients with herniated disc disease, at corresponding disc space levels, were included for study. In each case note was made of the presence, absence and direction of disc displacement and also the presence and location of neural contact with the displaced disc. Results In 33 of 38 (86.8%) patients in the spondylolisthesis group, the vertical disc displacement was upward. In the control group only 3 patients (7.8%) had upward vertical disc displacement. 19 patients (53%) from the spondylolisthesis group had exit foraminal nerve root contact, compared to 7 patients (18.4%) from the control group. 27 control patients (71%) had contact within the lateral recess, compared to only 6 patients (17%) with spondylolisthesis. Differences for upward displacement were significant ( p < 0.05). Conclusion Disc displacement in patients with spondylolisthesis is predominately in a cephalad and lateral direction. Although this disc displacement pattern can occur in patients without spondylolisthesis, its incidence is much greater in the subset of patients with concomitant spondylolisthesis. In the setting of acquired osseous narrowing of the exit foramen, this described pattern of disc displacement superiorly and laterally in spondylolisthesis increases the susceptibility of spondylolisthesis patients to radicular symptoms and accounts for the exiting nerve root being more commonly affected than the traversing nerve root.

Upright weight-bearing cervical flexion/extension dynamic magnetic resonance imaging: Case report and review of the literature

Conventional recumbent magnetic resonance imaging (MRI) of the cervical spine may underestimate disease because the imaging is performed in a non-dynamic, non-weight bearing position. The cervical myelogram may provide additional information but requires an invasive procedure and a post-myelogram computed tomography (CT) scan. We present a patient with cervical symptomatology imaged in an upright weight-bearing sitting position in the flexion, neutral, and extension positions. Measurements of the anterior to posterior midsagittal plane were obtained at several disc space levels. The T 2 sagittal images are presented and compared. This case clearly shows a reduction in the anterior–posterior distance in the midsagittal plane progressively from flexion to neutral to extension with the extension position showing the greatest reduction in cervical central canal diameter. Images show a decrease in anterior and posterior subarachnoid space in the extension position. Upright weight bearing cervical flexion/extension dynamic magnetic resonance imaging provides an innovative noninvasive technique to see changes in midsagittal cervical spinal canal diameter and may provide for imaging of the dynamic nature of spinal cord compression.

Combined use of locked and non-locked screws for plating of fractures in osteoporotic bone

Retrospective.The authors hypothesized that cervical lordosis (CL) would decrease with aging and increasing degeneration.It is theorized that with age and degeneration, the cervical spine loses lordosis and becomes progressively more kyphotic; however, no studies support these conclusions in patients with various spinal deformities.The authors performed a radiographic analysis of asymptomatic adults (referring to their cervical spine) of varying ages, with differing forms of spinal deformity to the thoracic/lumbar spine to see how cervical lordosis changes with increasing age. A total of 104 total spine EOS X-rays of adult (aged >18 years) spinal deformity patients without documented neck pain, prior neck surgery, or cervical deformity were reviewed. The researchers only reviewed EOS X-rays because they allow complete visualization from occiput to feet. Cervical lordosis, standard Cobb measurements, sagittal balance parameters, and cervical degeneration were quantified radiographically by the method previously described by Gore et al. Statistical analysis was performed with 1-way analysis of variance to compare significant differences between groups aged <40, 40–60 and >60 years as well as changes in sagittal balance. A p-value < .05 was considered significant.Average CL actually increased with increasing age (10.3 ± 14.7, 15.4 ± 15.1, and 23.3 ± 1.6.7 for age < 40, 40–60, and > 60 years, respectively; p < .05). Average cervical degeneration score increased at all disc space levels from C2 to C7 across age groups (0.7 ± 1.2, 9.9 ± 69, and 16.3 ± 8.9 for age <40, 40–60, and >60 years, respectively; p < .01), with the highest degeneration at the C5–6 and C6–7 disc spaces (3.7 ± 3.3 and 3.2 ± 2.9, respectively; p < .01). This increase did not correlate with the increase in CL seen with aging (r = 0.02; p = .84).Cervical lordosis increased with aging in adult spinal deformity patients. There was no relationship between cervical degeneration and lordosis despite the strong relationship seen between increasing CL in older age groups.

Anterior corpectomy and fusion with fibular strut grafts for multilevel cervical myelopathy

The authors conducted a study to investigate the long-term results and postoperative complications of a new surgical technique, fibular strut graft-assisted anterior corpectomy and fusion for multilevel (> four) cervical myelopathy. Multilevel anterior corpectomy and subsequent strut graft placement is considered a challenging procedure because of complications relating to graft dislodgment, pseudarthrosis, greater operative duration, and increased blood loss. The study comprised 100 patients with cervical myelopathy who underwent anterior corpectomy and fusion and fibular strut graft placement at more than four disc space levels between 1989 and 1998. Single-screw fixation was used in conjunction with the autologous strut graft. Preoperative and postoperative plain radiographs, computerized tomography myelograms, and magnetic resonance images were obtained for assessment of fusion status. All complications and outcomes were analyzed based on clinical records to evaluate the results of the technique. There were no cases of graft dislodgment. The graft union rate was 85%. Analysis of clinical data showed that pseudarthrosis had no adverse effect on the clinical results. Adjacent-level disc degeneration occurred in 12% of patients, but in all cases the patients were asymptomatic. In 9% of cases C-5 palsy was observed but it recovered spontaneously. There were no infections and no case of neurological deterioration. With this new graft technique, graft dislodgment, the major complication associated with strut graft surgery, was resolved completely. This simple technique involving single-screw fixation provided good results when used in conjunction with anterior decompression and strut graft fixation with a very low incidence of complications.

Gender Differences of Regional Abdominal Fat Distribution and Their Relationships with Insulin Sensitivity in Healthy and Glucose-Intolerant Thais

To determine gender differences of regional abdominal fat distribution and their relationships with insulin sensitivity in healthy and glucose-intolerant Thais, 44 subjects, 22 men and 22 body mass index-matched women, with normal and abnormal glucose tolerance, which included subjects with impaired glucose tolerance and diabetes, were studied. Total body fat and total abdominal fat (TAF) at L1-L4 were measured by dual-energy x-ray absorptiometry. Regional abdominal fat, which consists of sc abdominal fat and visceral abdominal fat, was determined by single-slice computerized tomography of the abdomen at L4-L5 disc space level. Insulin sensitivity was determined by euglycemic hyperinsulinemic clamp and expressed as glucose infusion rate (GIR). With comparable body mass index, visceral abdominal fat was most strongly correlated with GIR after adjustment with percent total body fat in both healthy (r = -0.8155; P = 0.007) and glucose-intolerant women (r = -0.7597; P = 0.011), whereas TAF was most strongly correlated with GIR in both healthy (r = -0.8114; P = 0.008) and glucose-intolerant men (r = -0.6194; P = 0.101). By linear regression analysis, visceral abdominal fat accounted for 35.0% (beta = -3.53 x 10(-2); P = 0.001) of GIR variance in women, whereas TAF accounted for 39.3% (beta = -1.28 x 10(-4); P < 0.0001) of GIR variance in men. We conclude that there are gender differences in the relationships of regional abdominal fat and insulin sensitivity in slightly obese healthy and glucose-intolerant Thais, the difference of which may possibly be in part due to the difference of abdominal fat patterning between genders.