KJC Korea
Journal Central

Study Design: A prospective observational cohort study. Objectives: This study was conducted to analyze associations between the volume of the fusion mass and clinical outcomes 1 year after posterior lumbar interbody fusion (PLIF). Summary of Literature Review: No study has investigated associations between the size of the fusion mass and clinical outcomes after PLIF. Materials and Methods: The volume of the fusion mass and its clinical correlations after PLIF were analyzed in all patients and in subgroups. When a sufficient amount of local bone was available for grafting, only local bone without a graft extender was used (LbG group, n=20). If an inadequate amount of local bone was present for grafting, a local bone graft with porous hydroxyapatite bone chips was used (LbHa group, n=20). The same amount of demineralized bone matrix was used in both groups. The primary outcome was the relationship between the size of the fusion mass and clinical outcomes in all patients 1 year after surgery. The secondary outcome was a comparison of the size of the fusion mass and clinical outcomes by group. Results: The volume of the fusion mass was not correlated with any clinical outcomes 1 year after surgery, either in the overall group of patients or in the subgroup analysis. Conclusions: The volume of the interbody fusion mass was not related to any clinical outcomes 1 year after surgery. Furthermore, in cases with an insufficient amount of local bone for grafting, porous hydroxyapatite could be a relatively good alternative as a graft extender.

Study Design: Retrospective analysis. Objectives: This study was conducted to identify the correlations and usefulness of lateral cervical radiographs compared with wholespine sagittal lateral radiographs for evaluating cervical sagittal alignment. Summary of Literature Review: Few reports have compared cervical lateral radiographs with whole-spine sagittal radiographs. Materials and Methods: We retrospectively analyzed 181 patients with both cervical standing lateral radiographs and whole-spine standing lateral radiographs. The radiographs were evaluated using the following sagittal alignment parameters: C2-7 lordosis, C2-7 sagittal vertical axis (SVA), T1 slope, spino-cranial angle (SCA), and whole-spine SVA. We evaluated the relationships between the two radiographs. The patients were divided into four groups according to age and the measured sagittal parameters were compared across groups. An analysis according to clinical symptoms was also done. Results: C2-7 lordosis was 16.86° and 15.76°, C2-7 SVA was 15.76° and 16.86°, T1 slope was 29.03° and 22.49°, and SCA was 74.74° and 74.5°, respectively, on the cervical and whole spine radiographs. The whole-spine SVA was -2.64 mm. Correlation analysis between the two types of radiographs showed significant relationships for each sagittal parameter. The whole-spine SVA was related with wholespine C2-7 lordosis, T1 slope, and SCA. Cervical C2-7 lordosis and the whole-spine SVA increased with age. A decrease of C2-7 lordosis on whole-spine radiographs was shown in patients with neck pain. Conclusions: Cervical SVA and T1 slope were lower on whole-spine standing lateral radiographs than on simple cervical lateral radiographs. The cervical sagittal parameters measured on cervical radiographs were correlated with those measured on whole-spine radiographs. Cervical radiographs can be used to replace whole-spine radiographs with due consideration of these findings.

Study design: Retrospective comparative study. Objectives: The aim of this study was to analyze the usefulness of functional myelography in patients with a mismatch between symptoms and magnetic resonance imaging (MRI) findings. Summary of Literature Review: Functional myelography was a widely-used diagnostic tool decades ago, although it has been considered to be an old-fashioned technique since MRI was invented. Despite its invasiveness, functional myelography can be a useful method, with advantages in axial loading situations in symptomatic patients and its dynamic element at the point of imaging. Materials and Methods: From May 2017 to December 2018, 141 patients who underwent MRI, functional myelography, and surgical treatment were included, and the MRI and functional myelography results were compared. The independent-samples t-test and chi-square test were used to compare parameters, surgical results, and diagnoses using both methods between the matched and mismatched groups. The Fisher exact test was used for post hoc testing. Results: Ten patients (7.1%) had different diagnoses based on MRI and functional myelography. All of these patients’ symptoms matched the functional myelography results, and the patients had non-significantly different visual analogue scale scores for pain in both groups. The diagnoses made by MRI showed statistically significant differences, all of which were negative, in the mismatched group, but the patients did not show a significant difference when diagnosed by functional myelography. We performed surgical treatment according to the functional myelography results, and the patients’ symptoms were relieved, without a statistically significant difference. Conclusions: In patients with a mismatch between symptoms and MRI findings, functional myelography can be a useful additional diagnostic tool.

Study Design: A retrospective radiologic study. Objectives: To compare disc degeneration between the cervical and lumbar spine and to elucidate the patterns of degeneration according to the corresponding disc levels in the cervical and lumbar spine. Summary of Literature Review: Disc degeneration results from the aging process in the spine. However, the incidence of disc degeneration in the cervical and lumbar spine might differ due to anatomical differences Materials and Methods: We randomly selected 280 patients by age and sex among 6,168 patients who underwent cervical or lumbar spine magnetic resonance imaging combined with whole-spine T2 sagittal images from June 2006 to March 2012. We classified disc degeneration by the modified Matsumoto grading system and the Pfirrmann classification at 11 intervertebral disc levels from C2 to T1 and from L1 to S1. Results: There was no significant difference in disc degeneration between the cervical and lumbar spine in either grading system. No significant difference was found in the degree of disc degeneration between the lower two disc levels of the cervical spine and the lower two disc levels of the lumbar spine in either system (C5-C6, C6-C7, L4-L5, L5-S1). However, both grading systems showed more severe degeneration in upper two disc levels of the cervical spine than in the upper two disc levels of the lumbar spine (C2-C3, C3-C4, L1-L2, L2-L3). Conclusions: There was a significant difference in disc degeneration between the upper two disc levels of the cervical and lumbar spine. Adjacent segmental degeneration after fusion surgery might reflect the natural history of the condition, not adjacent segmental problems.

Study Design: Retrospective study. Objectives: This study analyzed the diagnostic and therapeutic usefulness of selective nerve root block (SNRB) in patients with spinal stenosis who show inconsistencies between magnetic resonance imaging (MRI) and clinical findings (e.g., dermatomes). Summary of Literature Review: MRI is known to be highly accurate for diagnosing spinal stenosis, but few studies have investigated the diagnostic accuracy of MRI for spinal canal stenosis. In addition, the most suitable treatment of patients with inconsistent clinical and MRI findings has not been established. Methods: This single-center, retrospective cohort study was conducted among 93 patients treated between January 2013 and December 2018, who underwent at least two SNRBs for single-level spinal stenosis on MRI with clinical discrepancies. Seventeen patients who were diagnosed with other causes of pain (e.g., spondylolisthesis, sacroiliac joint dysfunction, lower leg arterial occlusion) were excluded. The first SNRB targeted the lesion found on MRI. One week later, patients were assessed using a visual analog scale (VAS) and a second procedure was performed on the dermatome-indicated level if there was no improvement. VAS scores were also obtained 3 months after the procedure. Results: In total, 45 patients had central stenosis and 31 patients had foraminal stenosis. The average VAS score before the SNRB was 7.4±1.4. After the first procedure, the average VAS score was 5.2±2.6. After the second procedure, the average VAS score was 2.4±1.3, and after 3 months, it was 3.6±1.9. Of the patients with foraminal stenosis, 77.4% did not respond to the first block (based on MRI), but responded well to the second procedure (based on clinical symptoms) (p<0.05). Conclusions: SNRB targeting the level corresponding to clinical symptoms may be useful for locating the symptomatic nerve root and providing pain relief in patients with foraminal stenosis on MRI with discordant clinical findings.

Study Design: In this original study, a cross-sectional analysis was performed to evaluate websites with information on cervical disc herniation. Objectives: The purpose of this study was to assess the source and quality of information regarding cervical disc herniation available to patients on websites. Summary of Literature Review: Studies have shown that 92% of the Korean population regularly accesses and searches for medical information on websites. While a large amount of information exists on websites, there is a possibility that patients will be misled due to inaccurate information because there are no established criteria for qualitative evaluation. In addition, little research has been conducted on websites that provide information about cervical disc herniation. Materials and Methods: The search term ‘‘cervical disc herniation’’ was entered into the three most popular search engines in Korea (Naver, Daum, and Google). The first 50 websites displayed by each engine were selected for inclusion in this study and were categorized as academic, commercial, physician, non-physician, government organization, and unspecified. Information was assessed in terms of DISCERN, accuracy, and exhaustivity scores, and a total summary score was calculated for each website. Results: Among the theoretical total of 150 websites, 83 unique and relevant websites were identified. The distribution by source was as follows: non-physician, 34.9%; physician, 27.7%; commercial, 13.3%; unspecified, 10.8%; academic, 9.6%; and government, 3.6%. Academic and government websites obtained the highest total summary scores, with statistical significance when compared to other types (p=0.03). Conclusions: Website information on cervical disc herniation is generally limited. Institutional improvement efforts are needed to foster an environment where patients can receive high-quality medical information, and physician groups should play a central role in this process.

Study Design: Case report. Objective: We present a rare case of adhesive arachnoiditis that occurred after percutaneous endoscopic discectomy. Summary of Literature Review: Adhesive arachnoiditis can be caused by infection, trauma, surgery, and other iatrogenic injuries. Material and Methods: A 60-year-old man presented with acute onset of lower back pain, radiating to the right leg. His symptoms had developed 10 days previously without any trauma. He had a history of L4-5 percutaneous endoscopic discectomy 10 months ago. There was no evidence of infection in an examination of cerebrospinal fluid obtained from a spinal tap. However, magnetic resonance imaging showed peridural fibrosis, clumping of the nerve roots of the cauda equina with the pia mater, and dural enhancement at the L4-5 level. Results: His symptoms disappeared after steroid pulse therapy. Conclusions: Even minimally invasive surgery, such as endoscopic discectomy, can lead to adhesive arachnoiditis of the lumbar spine.