Yong-Eun Cho

Spinal surgery in patients with end-stage renal disease undergoing hemodialysis therapy.

Study Design. Case series retrospective review. Objective. To present the surgical treatment guideline for spinal diseases with end-stage renal disease (ESRD) patients undergoing hemodialysis. Summary of Background Data. Treatment for spinal diseases with ESRD patients in is a special clinical challenge because of complex medical and clinical problems. Methods. We retrospectively reviewed 12 patients who underwent spinal surgeries among patients with chronic renal failure at our hospital from May 2000 to September 2007. The medical records and radiologic findings for these patients were reviewed and concomitant medical diseases, laboratory findings, pre- and postoperative care, clinical outcomes, and complications were investigated. Results. One patient died of pneumonia and sepsis 2 months after fusion surgery. Other postoperative complications included postoperative delirium in 3 patients and terminal ileitis and delayed primary spondylodiscitis in 1 patient each. There were no postoperative wound infections associated with the spinal surgery. The preoperative mean visual analogue scale score was 7.9 ± 0.61, which improved to 2.2 ± 1.25 at the time of final follow-up for 11 patients. Among 5 patients who underwent fusion surgery, solid bone fusion was achieved in only 3 patients and included those who underwent posterior lumbar interbody fusion with pedicle screw fixation. In 2 patients who underwent posterior lumbar interbody fusion with cage alone, solid fusion was not achieved. In 1 of 2 patients who underwent anterior cervical fusion with plating, solid fusion was achieved. The overall fusion rate was 57.1% in patients with ESRD undergoing hemodialysis. Conclusion. Spinal surgeries in ESRD patients undergoing hemodialysis can be performed with acceptable outcomes; however, the complication rates and mortality rates are relatively high and the fusion rate is low. To obtain a better outcome, multiple factors such as comorbid medical diseases, laboratory abnormalities, and osteoporosis should be carefully considered.

Efficacy of postural reduction in osteoporotic vertebral compression fractures followed by percutaneous vertebroplasty.

OBJECTIVE:Vertebroplasty in the symptomatic osteoporotic vertebral fracture has become increasingly popular. However, there have been some limitations in restoring the height of the collapsed vertebrae and in preventing the leaking of cement. In the severely collapsed vertebrae of more than two thirds of their original height, vertebroplasty is regarded as a contraindication. We tried postural reduction using a soft pillow under the compressed level. This study was undertaken to investigate the effectiveness of the combination of postural reduction and vertebroplasty for re-expansion and stabilization of the osteoporotic vertebral fractures. METHODS:A total of 75 patients with single level vertebral compression fracture were treated with postural reduction followed by vertebroplasty. In 30 patients, the vertebral body was severely collapsed more than two-thirds of its original height. We calculated the compression ratio (anterior height/posterior height) and measured the Cobb angle. We analyzed the degree of re-expansion according to the onset duration. RESULTS:The mean compression ratio was 0.60 ± 0.15 initially and increased to 0.75 ± 0.17 after vertebroplasty. The mean Cobb angle was 16.14 ± 11.29° and corrected to 10.71 ± 12.08°. The degree of re-expansion showed significant relation with the onset duration. Twenty-eight of 30 (93%) severely collapsed vertebrae re-expanded after postural reduction, which made vertebroplasty possible. CONCLUSION:This new method of vertebroplasty leads to significant restoration of height and correction of kyphosis. The re-expansion was closely related with onset duration. In cases of severely collapsed vertebrae which is able to be re-expanded by postural reduction, vertebroplasty could be applied safely.

MAGNETIC RESONANCE IMAGING FINDINGS OF SUBSEQUENT FRACTURES AFTER VERTEBROPLASTY

OBJECTIVEThe biomechanical effect of injected cement has been considered as the cause of adjacent vertebral fracture (AVF) after vertebroplasty, but the clinical evidence supporting this hypothesis is still insufficient. METHODSWe retrospectively reviewed 33 patients with subsequent fractures among 278 patients who underwent percutaneous vertebroplasty at our hospital from January 2002 to December 2005. The bone marrow edema pattern of subsequent fractures on magnetic resonance imaging was analyzed in 33 patients. In addition, the relationship between the location and distribution pattern of inserted cement and site of subsequent fractures was investigated. RESULTSAmong 33 subsequent fractures, we found 13 cranial AVFs, 7 caudal AVFs, and 13 remote fractures. The incidence rate of AVFs was 7.3% of 273 patients. Among 33 subsequent vertebral fractures, 13 were cranial AVFs (Group 1), 3 were superior, 7 were inferior, and 3 were overall (23.1%, 53.8%, and 23.1%, respectively). Of 7 caudal AVFs (Group 2), 7 were superior (100%). In 13 remote fractures (Group 3), 10 were superior, 1 was inferior, 2 were overall (76.9%, 7.7%, and 15.4%, respectively). In AVFs, bone marrow edema appeared mainly toward injected cement (P = 0.005). When injected cement made a solid mass rather than interdigitation, the occurrence rate of cranial AVFs was high (P = 0.004). CONCLUSIONBone marrow edema of AVFs appeared significantly toward the previous injected cement. This phenomenon supports the idea that the biomechanical effect of injected cement is one of the causative factors which affect the occurrence of AVF after percutaneous vertebroplasty. In particular, when injected cement forms a solid mass rather than interdigitation, the risk of cranial AVF may increase.

Kyphoplasty versus vertebroplasty: restoration of vertebral body height and correction of kyphotic deformity with special attention to the shape of the fractured vertebrae.

Study Design Retrospective comparative analysis. Objective We analyzed kyphosis correction, vertebral height restoration, and bone cement leakage in patients treated by vertebroplasty (VP) and kyphoplasty (KP) to compare the effectiveness of VP and KP for the treatment of osteoporotic vertebral compression fractures. Summary of Background Data Superior results have been reported for the use of KP for kyphotic deformity correction and collapsed vertebral height restoration. However, there are no previous comparative reports comparing the efficacy of KP versus VP according to the shapes of fractured vertebrae. Methods A total of 103 patients underwent either VP (n=58) or KP (n=45) for treatment of osteoporotic vertebral compression fracture between October 2006 and September 2009. We organized the patients into 6 groups according to treatment method and fracture type: VP (wedge‐shaped), VP (V‐shaped), VP (flat‐shaped), KP (wedge‐shaped), KP (V‐shaped), and KP (flat‐shaped). Comparisons were performed for kyphosis correction, vertebral height restoration, and cement leakage between VP and KP groups. Results KP was more effective than VP, especially for middle column height restoration and bone cement leakage prevention, for all fracture types (P value <0.05). In addition, KP was more effective in anterior height restoration and kyphosis correction in both flat and wedge‐shape fractures (P value <0.05). However, posterior column vertebral height was not restored in either the KP group or the VP group. The clinical outcomes did not differ between the 2 groups (P value >0.05). Conclusions KP has a significant advantage over VP in terms of kyphosis correction, vertebral height restoration, and cement leakage prevention. KP has an obvious advantage in terms of middle vertebral height restoration and cement leakage prevention, especially for V‐shape compression fractures.

Clinical approach and surgical strategy for spinal diseases in pregnant women: a report of ten cases

Study Design. Case series retrospective review. Objective. To present the treatment guideline for spinal diseases in pregnant women. Summary of Background Data. Treatment for spinal diseases in pregnant women is a special clinical challenge because of complex medical and surgical clinical problems. Methods. We retrospectively reviewed 10 patients who underwent surgery for spinal diseases, who were diagnosed during pregnancy at our hospital from February 1992 to October 2005. Six patients had herniated lumbar discs, 3 patients had spinal tumors, and 1 patient had spinal tuberculosis. Results. Five patients with HLDs underwent partial hemilaminectomy and discectomy during pregnancy and maintained the pregnancy. One patient underwent posterior lumbar interbody fusion and had a therapeutic abortion 6 days after lumbar surgery. In 1 patient with hemangioblastoma at the level of T8–T9 level, prepartum surgery was performed maintaining pregnancy in gestational age, 29 weeks. In another patient with hemangioblastoma at the T10 level, a preoperative cesarean section and tumor removal surgery were performed under the same anesthesia in gestational age 34 weeks. One patient had recurrent intramedullary ependymoma at the C3–T2 level. She had the preterm baby by vaginal delivery before spinal operation in gestational age 33 weeks and underwent tumor removal surgery. One patient with tuberculous spondylitis at the level of T3–T5 level, therapeutic abortion performed in gestational age, 16 weeks because of inevitable radiation exposure during fusion surgery. Conclusion. In most spinal diseases, including HLD and tumors, prepartum surgical treatment can be safely performed maintaining pregnancy. For patients with progressive neurologic deficit at 34 to 36 weeks gestation or later, spine surgery should be performed following the induction of delivery or a cesarean section, or at the same time.

Predictors of successful outcome for lumbar chemonucleolysis: analysis of 3000 cases during the past 14 years.

OBJECTIVE Among numerous minimally invasive procedures for the treatment of herniated lumbar disc disease (HLD), chymopapain chemonucleolysis has the longest history of clinical usage. Long-term studies indicated good clinical results with a low risk for patients. However, much confusion still remains about the indications. This study was conducted to evaluate the predictors of successful outcome for chemonucleolysis and to firmly establish the proper indications for this procedure. METHODS Three thousand patients with HLD were treated with chemonucleolysis between 1984 and 1999. The clinical success rate in our series was 85%. The medical history and physical and radiological findings, including the type and direction of disc herniation, were analyzed retrospectively. RESULTS The patient group with the chief complaint of leg pain achieved a better clinical outcome than the patient group with low back pain (88% versus 59%, P < 0.05). A positive straight-leg-raising test was strongly correlated with good clinical outcome (P < 0.05). Patients manifesting a soft, protruded disc had a better outcome than those manifesting diffuse bulging disc (P < 0.05). Other prognostic factors favoring a good outcome were as follows: young age, short duration of symptoms, and no bony spur or calcification on radiological study. CONCLUSION Chymopapain chemonucleolysis is a safe and effective procedure. Proper selection of patients is important for the success of treatment. We propose the following three clinical criteria (Kim’s triad) for selection of patients: chief complaint of leg pain rather than back pain, positive straight-leg-raising test, and soft protruded disc.

Surgical Treatment of Primary Spinal Tumors in the Conus Medullaris

OBJECTIVE The objective of this study was to evaluate the characteristics and surgical outcome of the conus medullaris tumors. METHODS We retrospectively reviewed 26 patients who underwent surgery for conus medullaris tumor from August 1986 to July 2007. We analyzed clinical manifestation, preoperative MRI findings, extent of surgical resection, histopathologic type, adjuvant therapy, and outcomes. RESULTS There were ependymoma (13), hemangioblastoma (3), lipoma (3), astrocytoma (3), primitive neuroectodermal tumor (PNET) (2), mature teratoma (1), and capillary hemangioma (1) on histopathologic type. Leg pain was the most common symptom and was seen in 80.8% of patients. Pain or sensory change in the saddle area was seen in 50% of patients and 2 patients had severe pain in the perineum and genitalia. Gross total or complete tumor resection was obtained in 80.8% of patients. On surgical outcome, modified JOA score worsened in 26.9% of patients, improved in 34.6%, and remained stable in 38.5%. The mean VAS score was improved from 5.4 to 1.8 among 21 patients who had lower back pain and leg pain. CONCLUSION The surgical outcome of conus medullaris tumor mainly depends on preoperative neurological condition and pathological type. The surgical treatment of conus medullaris tumor needs understanding the anatomical and functional characteristics of conus meudllaris tumor for better outcome.

Nestin and small heat shock protein expression on reactive astrocytes and endothelial cells in cerebral abscess.

Cerebral abscess results in an extensive capsular formation, which is an important limiting barrier for the spread of microorganism. Reactive astrocytes and endothelial cells are major cellular components of the abscess capsule together with fibrocytes. Molecular pathogenesis that results in the migration and proliferation of these cells remain speculative. Intermediate filament (IF) nestin and small heat shock proteins (sHSP) are developmentally regulated protein. In this study, we found that nestin expression is re-induced in not only reactive astrocytes, but also in endothelial cells in the gliotic area of the capsule. These nestin expressing astrocytes and endothelial cells also expressed sHSPs, such as heat shock protein 27 (HSP27) and alphaB-crystalline. These results indicated that embryonic reversions of cytoskeletal proteins to nestin and the increased expression of sHSPs in in reactive astrocytes and endothelial cells are caused by pathogenic microorganism induced inflammatory stress.

Surgical outcomes after traumatic vertebral fractures in patients with ankylosing spondylitis.

Objective Ankylosing spondylitis is an inflammatory rheumatic disease mainly affecting the axial skeleton. The rigid spine may secondarily develop osteoporosis, further increasing the risk of spinal fracture. In this study, we reviewed fractures in patients with ankylosing spondylitis that had been clinically diagnosed to better define the mechanism of injury, associated neurological deficit, predisposing factors, and management strategies. Methods Between January 2003 and December 2013, 12 patients with 13 fractures with neurological complications were treated. Neuroimaging evaluation was obtained in all patients by using plain radiography, CT scan, and MR imaging. The ASIA Impairment Scale was used in order to evaluate the neurologic status of the patients. Management was based on the presence or absence of spinal instability. Results A total of 9 cervical and 4 thoracolumbar fractures were identified in a review of patients in whom ankylosing spondylitis had been diagnosed. Of these, 7 fractures were associated with a hyperextension mechanism. 10 cases resulted in a fracture by minor trauma. Posttraumatic neurological deficits were demonstrated in 11 cases and neurological improvement after surgery was observed in 5 of these cases. Conclusions Patients with ankylosing spondylitis are highly susceptible to spinal fracture and spinal cord injury even after only mild trauma. Initial CT or MR imaging of the whole spine is recommended even if the patients symptoms are mild. The patient should also have early surgical stabilization to correct spinal deformity and avoid worsening of the patients neurological status.

Anatomical parameters of fifth lumbar vertebra in L5–S1 spondylolytic spondylolisthesis from a surgical point of view

PurposeWe measured the length, width, height, and angles related to both Meyerding grading system and Marchetti–Bartolozzi classification in L5–S1 spondylolytic spondylolisthesis patients to investigate the anatomical characteristics of fifth lumbar pedicles.MethodsSeventy patients with L5–S1 spondylolytic spondylolisthesis and general spinal disease were included. Patient attributes, Meyerding grading system and Marchetti–Bartolozzi classification of spondylolisthesis, length, width, height of L4 and L5 pedicle, and the angle between pedicle and vertebral midline were measured. The heights of L5 vertebral body, divided as anterior, mid, and posterior were also measured.ResultsThe pedicle is elongated and the angle of the pedicle is wider in cases of L5–S1 spondylolysis. Vertebral body shape was more posteriorly wedged in L5–S1 spondylolysis. Pedicles were more narrow and shorter in L5–S1 spondylolysis.ConclusionsIn L5–S1 spondylolytic spondylolisthesis, a longer screw is suitable for insertion of L5 pedicle and the screw should be inserted more medially compared to patients without spondylolysis.