Anaphylaxis to Chlorhexidine-Impregnated Central Venous Catheters in Spine Surgery / 대한정형외과학회잡지

Attempts to lower rates of catheter-related bloodstream infection have led to the adoption of chlorhexidine-coated central venous catheters (CVCs) in several orthopedic surgeries. On the other hand, there is still some controversy regarding the advantage of reducing catheterrelated infections. This paper reports a case of severe anaphylaxis to chlorhexidine-coated CVCs when used in spine surgery. Before exposing the patients to chlorhexidine-coated CVCs, the risk of complications including anaphylaxis should be considered.

Whole Lumbar Spinal Subdural Hematoma with Progressive Paraplegia after Lumbar Spinal Epidural Injection / 대한정형외과학회잡지

Spinal hematomas are a rare but serious complication that is typically observed in the epidural space. Spinal subdural hematomas are a dangerous clinical situation because of their potential to cause significant compression of the neural elements and can be mistaken easily for spinal epidural hematomas. This paper reports a case of a severe whole lumbar subdural hematoma after a simple epidural injection that was treated with surgical decompression with excellent clinical results.

Radiological Assessment of the Effects of Anterior Cervical Discectomy and Fusion on Distraction of the Posterior Ligamentum Flavum in Patients with Degenerative Cervical Spines

Background@#This study aimed to assess the effects of anterior cervical discectomy and fusion (ACDF) on distraction of the posterior ligamentum flavum (LF) by increasing the intervertebral disc height and positioning a graft in patients with degenerative cervical spine disease. @*Methods@#Sixty-eight patients with degenerative cervical diseases who underwent single-level ACDF were included in the analysis. The intervertebral disc height, Cobb angle, and transverse thickness of the LF were measured, and magnetic resonance imaging was performed both preoperatively and 6 weeks postoperatively on each patient. Correlation analyses were performed to evaluate the relationships between age, sex, change in intervertebral disc height, Cobb angle, and position of the intervertebral implant according to the postoperative change in LF thickness. The position of the intervertebral implant was categorized as anterior, middle, or posterior. We also evaluated radiological effects according to the implant position. @*Results@#The mean intervertebral disc height increased from 5.88 mm preoperatively to 7.49 mm postoperatively. The Cobb angle was 0.88° preoperatively and 1.43° postoperatively. Age (p = 0.551), sex (p = 0.348), position of cage (p = 0.312), pre- and postoperative intervertebral disc height (p = 0.850, p = 0.900), Cobb angle (p = 0.977, p = 0.460), and LF thickness (p = 0.060, p = 1.00) were not related to changes in postoperative LF thickness. Postoperative increase in disc height was related to Cobb angle (r = 0.351, p = 0.038). No other factors were significantly related. The position of the cage was not related with the change of Cobb angle (p = 0.91), LF thickness (p = 0.31), or disc height (p = 0.54). @*Conclusions@#Change in the intervertebral disc height and the position of the intervertebral implant after ACDF did not affect the thickness of the LF after surgery in patients with degenerative cervical spine disease.

Relationships and Usefulness of Cervical Lateral Radiographs Compared with Whole-Spine Lateral Radiographs for Evaluating Cervical Sagittal Alignment

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.

Efficacy of Dynamic Radiographs in Routine Evaluations for Degenerative Cervical Spine Disease

Objectives@#To analyze the usefulness of flexion-extension radiographs in the diagnosis of degenerative cervical disease.Summary of Literature ReviewThere is little information about the efficacy of flexion-extension radiographs in the diagnosis of degenerative cervical disease. @*Methods@#and MaterialsWe analyzed 1,062 patients with cervical degenerative disease who underwent flexion-extension radiographs and computed tomography (CT) or magnetic resonance imaging (MRI). The range of motion of the cervical joints was measured. Segmental instability was evaluated using the sagittal translation (≥3.5 mm) between C2 and T1, the sagittal angulation (≥3.5°), the vertebral slip angle (≥ 10°), and the dynamic spinal canal stenosis (≤12 mm). The relationship between canal compromise on CT or MRI and radiological instability was also evaluated. @*Results@#Cervical range of motion was 36.45°±17.63° (range, 2.1°–106.6°). Segmental instability was observed in 484 patients (nine cases of sagittal translation, 79 cases of sagittal plane rotation, 415 cases of a vertical slip angle, and 21 cases of dynamic spinal stenosis). Segmental instability was related with pathology in 218 patients with available CT or MRI (42%, including five cases of sagittal translation, 32 cases of sagittal plane rotation, 171 cases of vertical slip angle, and 10 cases of dynamic spinal stenosis. @*Conclusions@#Flexion-extension radiographs of the cervical spine were useful in diagnosing and evaluating subaxial segmental instability.

Efficacy of Dynamic Radiographs in Routine Evaluations for Degenerative Cervical Spine Disease

Objectives@#To analyze the usefulness of flexion-extension radiographs in the diagnosis of degenerative cervical disease.Summary of Literature ReviewThere is little information about the efficacy of flexion-extension radiographs in the diagnosis of degenerative cervical disease. @*Methods@#and MaterialsWe analyzed 1,062 patients with cervical degenerative disease who underwent flexion-extension radiographs and computed tomography (CT) or magnetic resonance imaging (MRI). The range of motion of the cervical joints was measured. Segmental instability was evaluated using the sagittal translation (≥3.5 mm) between C2 and T1, the sagittal angulation (≥3.5°), the vertebral slip angle (≥ 10°), and the dynamic spinal canal stenosis (≤12 mm). The relationship between canal compromise on CT or MRI and radiological instability was also evaluated. @*Results@#Cervical range of motion was 36.45°±17.63° (range, 2.1°–106.6°). Segmental instability was observed in 484 patients (nine cases of sagittal translation, 79 cases of sagittal plane rotation, 415 cases of a vertical slip angle, and 21 cases of dynamic spinal stenosis). Segmental instability was related with pathology in 218 patients with available CT or MRI (42%, including five cases of sagittal translation, 32 cases of sagittal plane rotation, 171 cases of vertical slip angle, and 10 cases of dynamic spinal stenosis. @*Conclusions@#Flexion-extension radiographs of the cervical spine were useful in diagnosing and evaluating subaxial segmental instability.

Correction of Single Thoracic Adolescent Idiopathic Scoliosis Using Pedicle Screw Instrumentation: Comparison of Stainless Steel to Titanium Alloy Instruments / 대한정형외과학회잡지

PURPOSE: To compare the results of two different instruments made of stainless steel and titanium alloy for correction of single thoracic adolescent idiopathic scoliosis (AIS) using pedicle screw instrumentation. MATERIALS AND METHODS: A total of 141 patients with single thoracic AIS treated with pedicle screw instrumentation and selective thoracic fusion were retrospectively reviewed after a follow-up of 2 years. The patients had a main thoracic curve of 40° to 75° and were divided into two groups based on instrument materials; S group (stainless steel, n=90) and T group (titanium alloy, n=51). The diameter of the stainless steel rod used was 7.0 mm while that of the titanium alloy rod was 6.35 mm or 6.0 mm. Standing long-cassette radiographic measurements including various coronal and sagittal parameters for the preoperative, early postoperative and 2-year postoperative follow-up were analyzed. There were no significant differences in the preoperative curve characteristics between the two groups. RESULTS: In the S group, the preoperative main thoracic curve of 51.3°±8.4° was improved to 19.0°±7.6° (63.1% correction) and the lumbar curve of 32.3°±8.4° spontaneously decreased to 12.7°±8.2° (62.9% correction) at 2 years postoperatively. In the T group, the preoperative main thoracic curve of 49.5°±8.4° and the lumbar curve of 30.3°±8.9° was improved to 18.8°±7.4° (62.2% correction) and 11.3°±5.4° (63.3% correction), respectively. The corrections of coronal curves were not statistically different between the two groups (p>0.05). The thoracic kyphosis was changed from 16.8°±8.5° to 24.3°±6.1° in the S group and from 19.6°±11.2° to 26.6°±8.5° in the T group. There were no significant differences in the changes of sagittal curves, coronal and sagittal balances at the 2-year follow-up and the number of fused segments and used screws between the two groups (p>0.05). CONCLUSION: When conducting surgery for single thoracic AIS using pedicles screw instrumentation, two different instruments made of stainless steel and titanium alloy showed similar corrections for coronal and sagittal curves.

Etiology and Related Factors of Postoperative Delirium in Orthopedic Surgery

BACKGROUND: Delirium is a serious complication for elderly patients after orthopedic surgery. The purpose of this study was to assess the etiology and related factors of delirium after orthopedic surgery in Korea. METHODS: We retrospectively reviewed the medical records of 3,611 patients over 50 years who had orthopedic surgery. The age of patients (50s, 60s, 70s, and > 80s), type of anesthesia (general, spinal, and local), operation time (more than 2 hours vs. less than 2 hours), surgical site (spine, hip, knee, or others), and etiology (trauma or disease) were compared to determine possible risk factors of delirium after orthopedic surgery. RESULTS: Of 3,611 patients, 172 (4.76%) were diagnosed with delirium after orthopedic surgery. Postoperative delirium occurred in 1.18% in their 50s, 3.86% in their 60s, 8.49% in their 70s, and 13.04% in > 80s (p < 0.001). According to anesthesia type, 6.50% of postoperative delirium occurred after general anesthesia, 0.77% after spinal anesthesia, and 0.47% after local anesthesia (p < 0.001). More than 2 hours of operation was associated with higher occurrence of delirium than less than 2 hours was (5.88% vs. 4.13%, p = 0.017). For the etiology, 8.17% were trauma cases and 3.02% were disease (p < 0.001). Postoperative delirium occurred in 22 of 493 patients (4.46%) after spine surgery, 18 of 355 patients (5.07%) after hip surgery, 17 of 394 patients (4.31%) after knee surgery, and 15 of 1,145 patients (1.31%) after surgery at other sites (p < 0.001). CONCLUSIONS: Postoperative delirium was more common in older patients who had surgery under general anesthesia, whose surgery took more than 2 hours, and who were hospitalized through the emergency room.

Influence of Atlantoaxial Fusion on Sagittal Alignment of the Occipitocervical and Subaxial spines in Os Odontoideum with Atlantoaxial Instability

STUDY DESIGN: Retrospective case analysis. PURPOSE: We hypothesized that larger the C1–C2 fusion angle, greater the severity of the sagittal malalignment of C0–C1 and C2–C7. OVERVIEW OF LITERATURE: In our experience, instances of sagittal malalignment occur at C0–C1 and C2–C7 following atlantoaxial fusion in patients with Os odontoideum (OO). METHODS: We assessed 21 patients who achieved solid atlantoaxial fusion for reducible atlantoaxial instability secondary to OO. The mean patient age at the time of the operation was 42.8 years, and the mean follow-up duration was 4.9 years. Radiographic parameters were preoperatively measured and at the final follow-up. The patients were divided into two groups (A and B) depending on the C1–C2 fusion angle. In group A (n=11), the C1–C2 fusion angle was ≥22°, whereas in group B, it was <22°. The differences in the radiographic parameters of the two groups were evaluated. RESULTS: At the final follow-up, the C1–C2 angle was increased. However, this increase was not statistically significant (18° vs. 22°, p=0.924). The C0–C1 angle (10° vs. 5°, p<0.05) and C2–C7 angle (22° vs. 13°, p<0.05) significantly decreased. The final C1–C2 angle was negatively correlated with the final C0–C1 and C2–C7 angles. The final C0–C1 angle (4° vs. 6°, p<0.05) and C2–C7 angle (8° vs. 20°, p<0.05) were smaller in group A than in group B. After atlantoaxial fusion, the C0–C1 range of motion (ROM; 17° vs. 9°, p<0.05) and the C2–C7 ROM (39° vs. 31°, p<0.05) were significantly decreased. CONCLUSIONS: We found a negative association between the sagittal alignment of C0–C1 and C2–C7 after atlantoaxial fusion and the C1–C2 fusion angle along with decreased ROM. Therefore, overcorrection of C1–C2 kyphosis should be avoided to maintain good physiologic cervical sagittal alignment.

Posterior Sublaminar Wiring and/or Transarticular Screw Fixation for Reducible Atlantoaxial Instability Secondary to Symptomatic Os Odontoideum: A Neglected Technique?

STUDY DESIGN: Retrospective case analysis. PURPOSE: We retrospectively evaluated the clinical and radiological outcomes of posterior sublaminar wiring (PSLW) and/or transarticular screw fixation (TASF) for reducible atlantoaxial instability (AAI) secondary to os odontoideum. OVERVIEW OF LITERATURE: Limited information is available about the surgical outcomes of symptomatic os odontoideum with AAI. METHODS: We examined 23 patients (12 women and 11 men) with os odontoideum and reducible AAI. The average age of the patients at the time of the operation was 44.2 years. The average follow-up duration was 4.5 years. Thirteen patients with anterior AAI underwent PSLW alone, while 10 patients with combined (anterior+posterior) AAI underwent PSLW and TASF. An autogenous iliac bone graft was used for all patients. Nine patients complained of neck or suboccipital pain, and 14 complained of myelopathy. RESULTS: Angulational instability (preoperative 18.7°±8.9° vs. postoperative 2.1°±4.6°, p<0.001), translational instability (16.3±4.9 mm vs. 1.8±2.2 mm, p<0.001), and segmental angle of the C1–C2 joint (23.7°±7.2° vs. 28.4°±3.8°, p<0.05) showed significant improvement postoperatively. Neck Visual Analog Scale score (6.2±2.4 vs. 2.5±1.8, p<0.05) and the modified Japanese Orthopedic Association (9.1±3.1 vs. 13.2±2.6, p<0.05) score also improved, with a recovery rate of 51.8%. Among the three patients who developed nonunion and/or wire breakage, one underwent revision surgery with repeat PSLW and was finally able to achieve fusion. The final fusion rate was 91.3%. CONCLUSIONS: PSLW and/or TASF provided satisfactory clinical and radiological outcomes in reducible AAI secondary to os odontoideum without significant neurological complications. Our results suggest that PSLW and/or TASF can be considered a viable surgical option over segmental fixation in highly selected cases of os odontoideum with reducible AAI.

Analysis of Preoperative Factors Affecting Postoperative Spinal Canal Expansion after Posterior Decompression for the Treatment of Multilevel Cervical Myelopathy

STUDY DESIGN: Retrospective analysis OBJECTIVES: To evaluate preoperative factors related with spinal canal expansion after posterior decompression for the treatment of multilevel cervical myelopathy. SUMMARY OF LITERATURE REVIEW: Data about preoperative factors related with spinal canal expansion after posterior cervical decompression surgery are inconsistent. MATERIALS AND METHODS: We reviewed 67 patients with cervical myelopathy who underwent posterior laminectomy or laminoplasty. Radiologically, we evaluated the C2-7 Cobb angle and range of motion using X-rays from the preoperative assessment and final follow-up. Expansion of the spinal canal at 6 weeks postoperatively was evaluated using magnetic resonance imaging and compared with the preoperative values. The preoperative factors of age, sex, number of operated levels, operation method, and radiological parameters were investigated as factors potentially related to postoperative spinal canal expansion using multivariate regression and correlation analyses. The clinical outcome was analyzed by the Neck Disability Index (NDI) and Japanese Orthopaedic Association (JOA) scores. RESULTS: The postoperative spinal canal expansion was 4.76 mm in sagittal images and 4.31 mm in axial images, with higher values observed in males and cases of severe preoperative cord compression. A lordotic preoperative Cobb angle was related to postoperative spinal canal expansion and JOA score improvement, but without statistical significance. The clinical outcomes of NDI (18.3→14.8) and JOA scores (10.81→14.6) showed improvement, but were not significantly related with any preoperative factors. CONCLUSIONS: The amount of preoperative spinal canal stenosis was associated with postoperative spinal canal expansion after posterior decompression in multilevel cervical myelopathy. The preoperative Cobb angle was not related to postoperative spinal canal expansion or clinical improvement.

Analysis of Preoperative Factors Affecting Postoperative Spinal Canal Expansion after Posterior Decompression for the Treatment of Multilevel Cervical Myelopathy

OBJECTIVES@#To evaluate preoperative factors related with spinal canal expansion after posterior decompression for the treatment of multilevel cervical myelopathy.SUMMARY OF LITERATURE REVIEW: Data about preoperative factors related with spinal canal expansion after posterior cervical decompression surgery are inconsistent.@*MATERIALS AND METHODS@#We reviewed 67 patients with cervical myelopathy who underwent posterior laminectomy or laminoplasty. Radiologically, we evaluated the C2-7 Cobb angle and range of motion using X-rays from the preoperative assessment and final follow-up. Expansion of the spinal canal at 6 weeks postoperatively was evaluated using magnetic resonance imaging and compared with the preoperative values. The preoperative factors of age, sex, number of operated levels, operation method, and radiological parameters were investigated as factors potentially related to postoperative spinal canal expansion using multivariate regression and correlation analyses. The clinical outcome was analyzed by the Neck Disability Index (NDI) and Japanese Orthopaedic Association (JOA) scores.@*RESULTS@#The postoperative spinal canal expansion was 4.76 mm in sagittal images and 4.31 mm in axial images, with higher values observed in males and cases of severe preoperative cord compression. A lordotic preoperative Cobb angle was related to postoperative spinal canal expansion and JOA score improvement, but without statistical significance. The clinical outcomes of NDI (18.3→14.8) and JOA scores (10.81→14.6) showed improvement, but were not significantly related with any preoperative factors.@*CONCLUSIONS@#The amount of preoperative spinal canal stenosis was associated with postoperative spinal canal expansion after posterior decompression in multilevel cervical myelopathy. The preoperative Cobb angle was not related to postoperative spinal canal expansion or clinical improvement.

Clinical Efficacy of Cages in Anterior Cervical Fusion for Degenerative Cervical Disease

OBJECTIVES@#To present up-to-date information on the use of cages in anterior cervical fusion for degenerative cervical disease.SUMMARY OF LITERATURE REVIEW: The use of cages in anterior cervical fusion for degenerative cervical disease remains controversial.@*MATERIALS AND METHODS@#Review of the relevant literature.@*RESULTS@#The use of cages in anterior cervical fusion of one and multiple disc levels was effective in terms of biomechanical stability and clinical outcomes without complications at the donor site compared with use of an autograft. However, the use of only a cage had many drawbacks, so the combined use of a cage and a cervical plate is recommended.@*CONCLUSIONS@#The use of cages in anterior cervical fusion was effective in terms of clinical outcomes, and the combined use of a cage and a cervical plate is recommended.

Clinical Efficacy of Cages in Anterior Cervical Fusion for Degenerative Cervical Disease

STUDY DESIGN: Review of the literature.OBJECTIVES: To present up-to-date information on the use of cages in anterior cervical fusion for degenerative cervical disease.SUMMARY OF LITERATURE REVIEW: The use of cages in anterior cervical fusion for degenerative cervical disease remains controversial.MATERIALS AND METHODS: Review of the relevant literature.RESULTS: The use of cages in anterior cervical fusion of one and multiple disc levels was effective in terms of biomechanical stability and clinical outcomes without complications at the donor site compared with use of an autograft. However, the use of only a cage had many drawbacks, so the combined use of a cage and a cervical plate is recommended.CONCLUSIONS: The use of cages in anterior cervical fusion was effective in terms of clinical outcomes, and the combined use of a cage and a cervical plate is recommended.

The Effect of Distal Hooks in Thoracolumbar Fusion Using a Pedicle Screw in Elderly Patients / 대한정형외과학회잡지

PURPOSE: To investigate the clinical outcomes of distal hook augmentation using a pedicle screw in thoracolumbar fusion in elderly patients. MATERIALS AND METHODS: This retrospective multicenter study recruited 20 patients aged 65 years or older, who underwent anterior support and long level posterior fusion in the thoracolumbar junction with a follow-up of one year. To assess the effect of distal hook augmentation, the patients were divided into two groups; the pedicle screw with hook group (PH group, n=10) and the pedicle screw alone group (PA group, n=10). RESULTS: The average age was 72.4 years (65–83 years). The average fusion segment was 4.6 segments (3–6 segments). There were no significant differences in age, sex, causative diseases, bone mineral density of lumbar and proximal femur, number of patients with osteoporosis, and number of fused segments between the two groups (p≥0.05). At 1 year follow-up after surgery, parameters related with distal screw pullout were significantly worse in the PA group. No patients in the PH group had distal screw pullout. However, six patients (60%, 6/10) in the PA group had distal screw pullout. There were no significant differences in the progression of distal junctional kyphosis between the two groups. CONCLUSION: Distal hook augmentation is an effective procedure in protecting distal pedicle screws against the pullout when long level thoracolumbar fusion was performed in elderly patients aged 65 years or older.

Anterior Cervical Fusion Using a Zero-Profile Stand-Alone Cage: Radiological and Clinical Outcomes after More than 2 Years of Follow-Up

STUDY DESIGN: Retrospective analysis. OBJECTIVES: To analyze the usefulness of Zero-P® by analyzing the radiological and clinical outcomes with a minimum of 2 years of follow-up. SUMMARY OF LITERATURE REVIEW: Anterior discectomy and fusion (ACDF) using Zero-P® showed excellent results. However, there is a lack of studies focusing on long-term outcomes. MATERIALS AND METHODS: Ninety-eight patients who underwent single-level ACDF using Zero-P® with more than 2 years of follow-up were included for analysis. In the radiological analysis, we evaluated disc height, segmental lordosis, and subsidence in the preoperative, postoperative, and last follow-up periods. The Neck Disability Index (NDI), Neck Visual Analogue Scale (VAS), and Arm VAS were also evaluated for clinical assessment. Radiological bony fusion was assessed, and radiological and clinical differences according to bony fusion were evaluated. RESULTS: Intervertebral disc height had increased 2.92 mm after surgery and subsided to 2.36 mm at the final follow-up. Subsidence of the screw was 0.58 mm at final follow-up. Segmental lordosis was 3.97° at the preoperative assessment, 8.39° in the postoperative follow-up, and 5.83° in the last follow-up. The Neck VAS score was 4.47, 2.28, and 1.27, respectively. The Arm VAS score was 5.73, 3.13, and 2.18; and NDI score was 17.8, 11.7, and 7.89, respectively. There was no association between the radiological and clinical results. Radiological nonunion was found in 18 subjects. There were no significant differences in radiological and clinical parameters according to bony union. CONCLUSIONS: ACDF with Zero-P® for treatment of degenerative cervical disease showed subsidence in 55.1% and nonunion in 18% of cases. However, the radiological results were not related to the clinical results.

Risk Factors for Subsequent Vertebral Compression Fracture Following Osteoporotic Compression Fracture / 대한정형외과학회잡지

PURPOSE: To evaluate the risk factors for subsequent vertebral fracture following acute osteoporotic vertebral compression fracture. MATERIALS AND METHODS: This was a multicenter retrospective study. We recruited 135 patients treated for acute osteoporotic compression fracture with available spine image taken at the 1-year follow-up mark in 3 different hospitals. The patients were divided into 2 groups in accordance with the occurrence of subsequent vertebral fracture. Variables including age, sex, bone mineral density, medical comorbidity, acute fracture level, presence of prior vertebral fracture, osteoporosis medication, and treatment method were analyzed and compared between the 2 groups. RESULTS: The new subsequent vertebral fractures were detected in 25 patients (18.5%). There were no significant differences between the 2 groups with respect to age, sex, medical comorbidity, presence of prior vertebral fracture, and acute fracture level, as shown by univariate analysis. However, in the group with subsequent vertebral fracture, more patients were treated by vertebroplasty or kyphoplasty and had a femur neck T-score of ≤-2.5, as well as poor compliance of osteoporosis medication with significant difference (p<0.05). According to the multivariate analysis, subsequent vertebral fractures were significantly influenced by vertebroplasty or kyphoplasty (p=0.003, odds ratio=4.71) and femur neck T-score of ≤-2.5 (p=0.013, odds ratio=3.47). CONCLUSION: Subsequent vertebral fractures were found in 19% at the 1-year mark after the treatment of acute osteoporotic compression fracture. The two risk factors for subsequent vertebral fractures were vertebroplasty or kyphoplasty and femur neck T-score of ≤-2.5.

Significance of Intramedullary High Signal Intensity on Magnetic Resonance Imaging in Patients with Cervical Ossification of the Posterior Longitudinal Ligament

BACKGROUND: The purpose of this study was to analyze the relation between intramedullary high signal intensity (IMHS) on magnetic resonance imaging (MRI), radiographic parameters, and clinical symptoms in cervical ossification of the posterior longitudinal ligament (OPLL) patients. METHODS: Two hundred forty-one patients, who underwent simple radiography, computed tomography (CT), and MRI were included in the present study. As radiographic parameters, the OPLL occupying ratio and occupying area were measured on CT images. Dynamic factors were assessed by measuring cervical range of motion (ROM) on simple radiographs. Visual analog scale (VAS) for neck and arm pain, and Japanese Orthopaedic Association (JOA) scores were evaluated for clinical analysis. The differences in radiographic and clinical findings were assessed between patients with IMHS on T2-weighted MRI findings (group A) and patients without IMHS (group B). RESULTS: Eighty-one patients were assigned to group A and 160 patients to group B. The occupying ratios were found to be higher in group A than in group B on both sagittal and axial views (p < 0.01). Group A also showed a higher area occupying ratio (p < 0.01). The length and area of underlying spinal canal on the sagittal and cross-sectional planes were lower in group A than in group B (p < 0.01). No significant difference in ROM was observed (p = 0.63). On the clinical findings, group A had a lower JOA score (p < 0.001), and no intergroup differences in VAS scores were observed. CONCLUSIONS: In cervical OPLL cases, IMHS on MRI was associated with manifestation of myelopathic symptom. Occupying ratio was associated with high signal intensity on MRI, whereas no association was found with ROM. Occurrence of high signal intensity increased inversely with the length and area of underlying spinal canal.

Analysis of Treatment Methods for Subsequent Vertebral Fractures Following Osteoporotic Compression Fractures

STUDY DESIGN: A multicenter retrospective study. OBJECTIVES: To compare the incidence and pattern of subsequent vertebral fractures following conservative treatment versus vertebroplasty or kyphoplasty for acute osteoporotic vertebral compression fractures. SUMMARY OF LITERATURE REVIEW: Previous studies suggest that new vertebral fractures may increase following vertebroplasty or kyphoplasty because bony cement inserted into the vertebral body of a fractured bone can elevate its strength and stiffness, which in turn, may increase the probability of the compression fractures. MATERIALS AND METHODS: From three hospitals, we recruited 135 patients who had been treated for acute osteoporotic compression fractures and had available spine images taken at their 1-year follow-up. The patients were divided into two groups according to treatment methods. Group C had been managed conservatively, and Group VK had undergone vertebroplasty or kyphoplasty. The two groups were compared for subsequent vertebral fractures. RESULTS: Group C consisted of 76 patients, and Group VK had 59. There were no significant differences between the two groups in terms of age, sex, medical comorbidity, body mass index (BMI), bone mineral density, presence of prior vertebral fracture or acute fracture level (p>0.05). New vertebral fractures were detected in 25 patients (19% of total subjects): 6 (8%) from Group C, and 19 (32%) from Group VK, demonstrating a significantly higher incidence in the VK group (p=0.0007). In the subgroup analysis, there was no significant difference between vertebroplasty and kyphoplasty (p>0.05). While four of the six patients (67%) in Group C had subsequent fractures in nonadjacent vertebrae, 14 of the 19 patients (74%) in Group VK had subsequent fractures in adjacent vertebrae. CONCLUSIONS: Subsequent vertebral fractures were found in 19% of subjects at one year after treatment for acute osteoporotic compression fractures. Compared with conservative treatment, vertbroplasty or kyphoplasty significantly increased the occurrence of subsequent vertebral fractures, which appeared more often in adjacent vertebrae.

Adjacent Segment Pathology Following Anterior Decompression and Fusion Using Cage and Plate for the Treatment of Degenerative Cervical Spinal Diseases

STUDY DESIGN: Retrospective study. PURPOSE: To analyze the incidence and prevalence of clinical adjacent segment pathology (CASP) following anterior decompression and fusion with cage and plate augmentation for degenerative cervical diseases. OVERVIEW OF LITERATURE: No long-term data on the use of cage and plate augmentation have been reported. METHODS: The study population consisted of 231 patients who underwent anterior cervical discectomy and fusion (ACDF) with cage and plate for degenerative cervical spinal disease. The incidence and prevalence of CASP was determined by using the Kaplan-Meier survival analysis. To analyze the factors that influence CASP, data on preoperative and postoperative sagittal alignment, spinal canal diameter, the distance between the plate and adjacent disc, extent of fusion level, and the presence or absence of adjacent segment degenerative changes by imaging studies were evaluated. RESULTS: CASP occurred in 15 of the cases, of which 9 required additional surgery. At 8-year follow-up, the average yearly incidence was 1.1%. The rate of disease-free survival based on Kaplan-Meier survival analysis was 93.6% at 5 years and 90.2% at 8 years. No statistically significant differences in CASP incidence based on radiological analysis were observed. Significantly high incidence of CASP was observed in the presence of increased adjacent segment degenerative changes (p<0.001). CONCLUSIONS: ACDF with cage and plate for the treatment of degenerative cervical disease is associated with a lower incidence in CSAP by 1.1% per year, and the extent of preoperative adjacent segment degenerative changes has been shown as a risk factor for CASP.