Byung-Ho Jin

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.

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.

Surgical Treatments for Lumbar Disc Disease in Adolescent Patients; Chemonucleolysis / Microsurgical Discectomy / PLIF with Cages

The herniated lumbar disc (HLD) in adolescent patients is characterized by typical discogenic pain that originates from a soft herniated disc. It is frequently related to back trauma, and sometimes it is also combined with a degenerative process and a bony spur such as posterior Schmorls node. Chemonucleolysis is an excellent minimally invasive treatment having these criteria: leg pain rather than back pain, severe limitation on the straight leg raising test (SLRT), and soft disc protrusion on computed tomography (CT). Microsurgical discectomy is useful in the cases of extruded or sequestered HLD and lateral recess stenosis due to bony spur because the nerve root is not decompressed with chymopapain. Spinal fusion, like as PLIF, should be considered in the cases of severe disc degeneration, instability, and stenosis due to posterior central bony spur. In our study, 185 adolescent patients, whose follow-up period was more than 1 year (the range was 1 - 4 years), underwent spinal surgery due to HLD from March, 1998 to December, 2002 at our institute. Among these cases, we performed chemonucleolysis in 65 cases, microsurgical discectomy in 94 cases, and posterior lumbar interbody fusion (PLIF) with cages in 33 cases including 7 reoperation cases. The clinical success rate was 91% for chemonucleolysis, 95% for microsurgical disectomy, and 89% for PLIF with cages, and there were no nonunion cases for the PLIF patients with cages. In adolescent HLD, chemonucleolysis was the 1st choice of treatment because the soft adolescent HLD was effectively treated with chemonucleolysis, especially when the patient satisfied the chemonucleolysis indications.

Intradural Lumbar Disc Herniations Associated with Epidural Adhesion : Report of Two Cases

Intradural lumbar disc herniation (ILDH) is rare. In this report, authors present 2 cases of ILDHs associated with severe adhesion between the dural sac and posterior longitudinal ligament. In a 40-year-old man, ILDH occurred in association with epidural adhesion due to ossification of the posterior longitudinal ligament (OPLL). In other 31-year-old man, ILDH occurred in presence of epidural adhesion due to previous spine surgery.

Long Term Efficacy of Posterior Lumbar Interbody Fusion with Standard Cages alone in Lumbar Disc Diseases Combined with Modic Changes

OBJECTIVE Posterior lumbar interbody fusion (PLIF) is considered to have the best theoretical potential in promoting bony fusion of unstable vertebral segments by way of a load sharing effect of the anterior column. This study was undertaken to investigate the efficacy of PLIF with cages in chronic degenerative disc disease with Modic degeneration (changes of vertebral end plate). METHODS A total of 597 patients underwent a PLIF with threaded fusion cages (TFC) from 1993 to 2000. Three-hundred-fifty-one patients, who could be followed for more than 3 years, were enrolled in this study. Patients were grouped into 4 categories according to Modic classification (no degeneration : 259, type 1 : 26, type 2 : 55, type 3 : 11). Clinical and radiographic data were evaluated retrospectively. RESULTS The clinical success rate according to the Prolos functional and economic outcome scale was 86% in patients without degeneration and 83% in patients with Modic degeneration. The clinical outcomes in each group were 88% in type 1, 84% in type 2, and 73% in type 3. The bony fusion rate was 97% in patients without degeneration and 83% in patients with Modic degeneration. The bony fusion rate in each group was 81% in type 1, 84% in type 2, and 55% in type 3. The clinical success and fusion rates were significantly lower in patients with type 3 degeneration. CONCLUSION The PLIF with TFC has been found to be an effective procedure for lumbar spine fusion. But, the clinical outcome and bony fusion rates were significantly low in the patients with Modic type 3. The authors suggest that PLIF combined with pedicle screw fixation would be the better for them.

Cortical margining capabilities of fins associated with ventral cervical spine instrumentation.

Fins incorporated into the design of a dynamic cervical spine implant have been employed to enhance axial load-bearing ability, yet their true biomechanical advantages, if any, have not been defined. Therefore, the goal of this study was to assess the biomechanical and axial load-bearing contributions of the fin components of the DOC ventral cervical stabilization system. Eighteen fresh cadaveric thoracic vertebrae (T1-T3) were obtained. Three test conditions were devised and studied: Condition A (DOC implants with fins were placed against the superior endplate and bone screws were not inserted); Condition B (DOC implant without fins was placed and bone screws were inserted); and Condition C (DOC implant with fins were placed against the superior endplate and bone screws were inserted). Specimens were tested by applying a pure axial compressive load to the superior platform of the DOC construct, and load-displacement data were collected. Condition C specimens had the greatest stiffness (459 ± 80 N/mm) and yield load (526±168 N). Condition A specimens were the least stiff (266±53 N/mm), and had the smallest yield loads (180±54 N). The yield load of condition A plus condition B was approximately equal to that of condition C, with condition A contributing about one-third and condition B contributing two-thirds of the overall load-bearing capacity. Although the screws alone contributed to a substantial portion of axial load-bearing ability, the addition of the fins further increased load-bearing capabilities.