This study aimed to evaluate the reproducibility of a new grading system for lumbar foraminal stenosis.
Four grades were developed for lumbar foraminal stenosis on the basis of sagittal MRI. Grade 0 ...refers to the absence of foraminal stenosis; grade 1 refers to mild foraminal stenosis showing perineural fat obliteration in the two opposing directions, vertical or transverse; grade 2 refers to moderate foraminal stenosis showing perineural fat obliteration in the four directions without morphologic change, both vertical and transverse directions; and grade 3 refers to severe foraminal stenosis showing nerve root collapse or morphologic change. A total of 576 foramina in 96 patients were analyzed (from L3-L4 to L5-S1). Two experienced radiologists independently assessed the sagittal MR images. Interobserver agreement between the two radiologists and intraobserver agreement by one reader were analyzed using kappa statistics.
According to reader 1, grade 1 foraminal stenosis was found in 33 foramina, grade 2 in six, and grade 3 in seven. According to reader 2, grade 1 foraminal stenosis was found in 32 foramina, grade 2 in six, and grade 3 in eight. Interobserver agreement in the grading of foraminal stenosis between the two readers was found to be nearly perfect (kappa value: right L3-L4, 1.0; left L3-L4, 0.905; right L4-L5, 0.929; left L4-L5, 0.942; right L5-S1, 0.919; and left L5-S1, 0.909). In intraobserver agreement by reader 1, grade 1 foraminal stenosis was found in 34 foramina, grade 2 in eight, and grade 3 in seven. Intraobserver agreement in the grading of foraminal stenosis was also found to be nearly perfect (kappa value: right L3-L4, 0.883; left L3-L4, 1.00; right L4-L5, 0.957; left L4-L5, 0.885; right L5-S1, 0.800; and left L5-S1, 0.905).
The new grading system for foraminal stenosis of the lumbar spine showed nearly perfect interobserver and intraobserver agreement and would be helpful for clinical study and routine practice.
The purpose of this study was to determine reliable MRI findings suggesting disk herniation with cartilage endplate herniation in the lumbar spine.
The records of 73 patients who underwent lumbar ...spinal MRI and lumbar microdiskectomy between March 2005 and January 2009 were searched to find those with the diagnosis of disk herniation with cartilage endplate herniation confirmed during surgery. The following morphologic features were assessed: posterior corners (posterior marginal nodes, dorsal corner defects, Modic changes, and posterior osteophytes), mid endplates (endplate irregularities, Modic changes), and heterogeneous low signal intensity of extruded material. The chi-square test and multiple logistic regression analysis with age, body mass index, and sex as covariates were used for the analysis. The ROC curve was obtained with scores of the statistically significant MRI findings.
Posterior marginal nodes, posterior osteophytes, Modic changes in posterior corners, mid endplate irregularities, Modic changes in mid endplates, and heterogeneous low signal intensity of extruded material were significantly more frequent in patients with disk herniation with cartilage endplate herniation (0.000 < p < 0.009). The AUC for diagnosing disk herniation with cartilage endplate herniation with our scoring system of the six MRI findings (0-6) was 0.888.
The presence of disk herniation with cartilage endplate herniation could be ascertained with the following MRI findings: posterior marginal nodes, posterior osteophytes, mid endplate irregularities, heterogeneous low signal intensity of extruded material, and Modic changes in posterior corners and mid endplates.
The purposes of the present study are to evaluate the subsidence and nonunion that occurred after anterior cervical discectomy and fusion using a stand-alone intervertebral cage and to analyze the ...risk factors for the complications.
Thirty-eight patients (47 segments) who underwent anterior cervical fusion using a stand-alone polyetheretherketone (PEEK) cage and an autologous cancellous iliac bone graft from June 2003 to August 2008 were enrolled in this study. The anterior and posterior segmental heights and the distance from the anterior edge of the upper vertebra to the anterior margin of the cage were measured on the plain radiographs. Subsidence was defined as ≥ a 2 mm (minor) or 3 mm (major) decrease of the segmental height at the final follow-up compared to that measured at the immediate postoperative period. Nonunion was evaluated according to the instability being ≥ 2 mm in the interspinous distance on the flexion-extension lateral radiographs.
The anterior and posterior segmental heights decreased from the immediate postoperative period to the final follow-up at 1.33 ± 1.46 mm and 0.81 ± 1.27 mm, respectively. Subsidence ≥ 2 mm and 3 mm were observed in 12 segments (25.5%) and 7 segments (14.9%), respectively. Among the expected risk factors for subsidence, a smaller anteroposterior (AP) diameter (14 mm vs. 12 mm) of cages (p = 0.034; odds ratio OR, 0.017) and larger intraoperative distraction (p = 0.041; OR, 3.988) had a significantly higher risk of subsidence. Intervertebral nonunion was observed in 7 segments (7/47, 14.9%). Compared with the union group, the nonunion group had a significantly higher ratio of two-level fusion to one-level fusions (p = 0.001).
Anterior cervical fusion using a stand-alone cage with a large AP diameter while preventing anterior intraoperative over-distraction will be helpful to prevent the subsidence of cages. Two-level cervical fusion might require more careful attention for avoiding nonunion.
Objective
To evaluate whether a synthetic bone chip made of porous hydroxyapatite can effectively extend local decompressed bone graft in instrumented posterior lumbar interbody fusion (PLIF).
...Methods
130 patients, 165 segments, who had undergone PLIF with cages and instrumentation for single or double level due to degenerative conditions, were investigated retrospectively by independent blinded observer. According to the material of graft, patients were divided into three groups. HA group (19 patients, 25 segments): with hydroxyapatite bone chip in addition to autologous local decompressed bone, IBG group (25 patients, 28 segments): with autologous iliac crest bone graft in addition to local decompressed bone and LB group (86 patients, 112 segments): with local decompressed bone only. Radiologic and clinical outcome were compared among groups and postoperative complications, transfusion, time and cost of operation and duration of hospitalization were also investigated.
Results
Radiologic fusion rate and clinical outcome were not different. Economic cost, transfusion and hospital stay were also similar. But operation time was significantly longer in IBG group than in other groups. There were no lasting complications associated with HA and LB group with contrast to five cases with persisting donor site pain in IBG group.
Conclusion
Porous hydroxyapatite bone chip is a useful bone graft extender in PLIF when used in conjunction with local decompressed bone.
Retrospective study.
To determine if C1 lateral mass screws could be safely inserted without the use of fluoroscopy.
Standard surgical technique for C1 lateral mass screw placement uses ...intraoperative fluoroscopy. However, intraoperative fluoroscopy is time consuming, cumbersome, and exposes both the patient and surgical team to radiation.
Radiographic analysis and chart review. Surgical technique was analyzed in 3 components: feasibility to complete the screw insertion without intraoperative fluoroscopic guidance; occurrence of any intraoperative, perioperative complications; and radiologic assessment of screw positions on roentgenogram.
Forty-six C1 lateral mass screws were inserted in 24 consecutive patients who underwent posterior cervical fusion. There were 19 female and 5 male. The mean age was 63 +/- 18 years at the time of surgery. All C1 lateral mass screws were inserted unicortically using a microscope-assisted "free-hand" technique. The average intraoperative blood loss in C1-C2 fusion was 123 +/- 50 mL. The mean operative time for each C1-C2 fusion was 133 +/- 30 minutes. Satisfactory positions of C1 screws were noted in intraoperative and postoperative radiograph examinations. There was no mortality or wound infection. There was no cortical breach along the screw path palpated intraoperatively. No vertebral artery injury or cerebral spinal fluid leakage during the screw insertion was observed. However, one patient with a prior posterior cervical operation had a dural tear during the exposure, another had new occipital neuralgia, and a third patient had a symptomatic occipitocervical joint violation by a C1 screw, which was diagnosed only on computed tomography scans. The symptoms resolved after the C1 screws were removed.
Microscope-assisted "free-hand" C1 lateral mass screws insertion is a feasible and reproducible technique. which offers an alternative method of screw insertion without cumbersome and potentially harmful fluoroscopy.
Retrospective study.
To evaluate the outcomes of anterior decompression and fusion followed by posterior instrumented fusion using pedicle screws without intentional correction of severe angular ...kyphosis deformity with myelopathy.
Treatment of severe angular kyphosis with myelopathy is extremely difficult and dangerous. Although surgical circumferential spinal osteotomy via a single posterior approach has been reported in several studies, serious neurologic complications are a possible outcome.
Among 51 patients surgically treated for angular kyphosis from 1988 to 2004, 16 patients (follow-up period, 32-168 months; mean, 72 months) with severe (>70 degrees ) angular kyphosis with progressive myelopathic symptoms underwent anterior decompression and fusion, followed by posterior pedicle screw instrumentation and bone graft without attempted correction of the deformity. Radiologic assessment, clinical findings including pain and daily activity scores, and neurologic status using the modified Frankel grade were analyzed before surgery and at the last follow-up.
Curve progression or nonunion did not occur in any of the cases. The mean pain and daily activity score were 3.1 and 2.3 before surgery and 4.7 and 4.2 after surgery, respectively. The modified Frankel grade indicated that every patient but one had improved neurologic function by one or more grades. Nine (75%) of 12 patients with ankle clonus, 10 (71%) of 14 patients with Babinski sign, and 6 (55%) of 11 patients with bowel and bladder dysfunction showed full improvement at the last follow-up. Postoperative complications included 1 screw pullout case and 2 infection cases which resolved without incidence.
Anterior decompression and fusion followed by posterior pedicle screw instrumentation and fusion without correction effectively improved neurologic symptoms and halted progression of kyphotic deformity in cases of severe angular kyphosis with myelopathy.
OBJECTIVE:The purpose of this study was to optimize imaging parameters for diffusion tensor imaging (DTI) of the cervical spinal cord using a recently developed sensitivity-encoded (SENSE) imaging ...technique, which can substantially reduce susceptibility artifacts.
MATERIALS AND METHODS:One hundred twenty sets of DTIs were performed of the cervical spinal cord in 40 normal volunteers, using a SENSE-based echo-planar imaging technique with different parameters (b-values, numbers of diffusion gradient directions, number of excitations, and slice thickness) in a stepwise approach. In step 1, DTI was performed of the cervical spinal cord with different b-values 500, 700, 900 seconds/mm; then with different numbers of diffusion gradient directions 6, 15, 32 in step 2; different number of excitations 1, 3, 5 in step 3; and different slice thicknesses 2, 3, 4 mm in step 4. In each step, 30 sets of DTIs were obtained from 10 volunteers. To determine the optimal imaging parameters, 3 radiologists evaluated the qualities of fractional anisotropy (FA) maps and color FA maps by visual analysis. The number of reconstructed fibers was measured for quantitative analysis. All qualitative and quantitative comparisons were analyzed by statistical methods using the Friedmann test and the Wilcoxon signed rank test.
RESULTS:In step 1, DTIs using a b-value of 900 seconds/mm showed the highest number of reconstructed fibers and the best image quality of FA map and color map. In step 2, the use of 15 or 32 directions demonstrated better quality DTIs than 6 directions. No significant difference was evident between the quality of DTI with 15 directions and that with 32 directions. The scan time of DTI with 15 directions was shorter than with 32 directions. In step 3, as the number of excitations increased, the number of reconstructed fibers increased significantly and the image quality of the FA map and the color map improved significantly. In step 4, the numbers of reconstructed fibers were significantly the highest with a slice thickness of 4mm.
CONCLUSION:Optimal parameters for DTI in the cervical spinal cord included a b-value of 900 seconds/mm, 15 diffusion gradient directions, 5 excitations, and a slice thickness of 4mm.
To verify the usefulness of a fluoroscopy guided cervical interlaminar epidural steroid injection (CIESI) in patients with neck pain and cervical radiculopathy and to evaluate outcome predictors.
We ...retrospectively analyzed 91 patients from July 2004 to June 2005 in whom CIESI was initially performed for neck pain and cervical radiculopathy. Therapeutic effects were evaluated 2 weeks after the administration of CIESI, and CIESI effectiveness was graded using a five-point scale, namely, whether the pain had disappeared, was much improved, slightly improved, the same, or aggravated. We also used a visual analog scale (VAS) for the clinical evaluation. According to documentation and follow-up charts, we categorized treatments as effective or ineffective. Possible outcome predictors, namely, diagnosis (spinal stenosis vs herniated disc), primary symptoms (neck pain vs radiculopathy vs both), age, gender, and duration of pain (more or less than 6 months) were also analyzed. Fisher's exact test, the chi-square test, and multiple logistic regression analysis were used for the statistical analysis.
After their medical records had been reviewed, 76 patients were included in this study. Inclusion criteria were: the availability of a cross-sectional image, such as a CT scan or an MR image, and a follow-up record after injection.
The medical records of 76 patients (male:female = 41 : 35) of mean age 53.1 years (range 32 years to 82 years) were reviewed. Two weeks after injection, 55 patients (72.4%) had experienced effective pain relief. Patients with herniated discs had significantly better results than patients with spinal stenosis (86.1% vs 60.0%) (P < 0.05). Other non-significant predictors of an improved outcome included: a symptom duration of <6 months, a young age, and the presence of cervical radiculopathy. Multiple regression analysis showed that the only factor that was significantly associated with outcome was the cause of the pain, i.e., herniated disc or spinal stenosis. Fluoroscopy guided CIESI is a safe and effective means of treating patients with neck pain and cervical radiculopathy. The most important outcome predictor was cause of pain, and patients with herniated disc experienced better pain relief than those with spinal stenosis.
The present study was undertaken to evaluate the effectiveness of transforaminal epidural steroid injection (TFESI) with using a preganglionic approach for treating lumbar radiculopathy when the ...nerve root compression was located at the level of the supra-adjacent intervertebral disc.
The medical records of the patients who received conventional TFESI at our department from June 2003 to May 2004 were retrospectively reviewed. TFESI was performed in a total of 13 cases at the level of the exiting nerve root, in which the nerve root compression was at the level of the supra-adjacent intervertebral disc (the conventional TFESI group). Since June 2004, we have performed TFESI with using a preganglionic approach at the level of the supra-adjacent intervertebral disc (for example, at the neural foramen of L4-5 for the L5 nerve root) if the nerve root compression was at the level of the supra-adjacent intervertebral disc. Using the inclusion criteria described above, 20 of these patients were also consecutively enrolled in our study (the preganglionic TFESI group). The treatment outcome was assessed using a 5-point patient satisfaction scale and by using a VAS (visual assessment scale). A successful outcome required a patient satisfaction scale score of 3 (very good) or 4 (excellent), and a reduction on the VAS score of > 50% two weeks after performing TFESI. Logistic regression analysis was also performed.
Of the 13 patients in the conventional TFESI group, nine showed satisfactory improvement two weeks after TFESI (69.2%). However, in the preganglionic TFESI group, 18 of the 20 patients (90%) showed satisfactory improvement. The difference between the two approaches in terms of TFESI effectiveness was of borderline significance (p = 0.056; odds ratio: 10.483).
We conclude that preganglionic TFESI has the better therapeutic effect on radiculopathy caused by nerve root compression at the level of the supra-adjacent disc than does conventional TFESI, and the difference between the two treatments had borderline statistical significance.
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