KJC Korea
Journal Central

Study Design: A retrospective study. Objectives: To compare the radiological and clinical results between cage and cancellous allograft mixed with bone marrow for monosegmental instrumented posterior lumbar interbody fusion (PLIF). Summary of the Literature Review: Allograft has potential problems, such as delayed union. Autologous bone marrow provides for improving the capability of bone induction with allograft. There are rare reports on PLIF using allograft mixed with autologous bone marrow. Materials and Methods: Monosegmental instrumented PLIF was performed on 51 patients who had lumbar degenerative disease, cage for 28 patients (cage group) and allograft mixed with bone marrow for 23 patients (allograft group). The clinical and radiological results in each group were compared. Results: The mean follow-up was 45 (30 - 111) months. At the final follow up, there was no significant difference between the cage group and the allograft group in the Korean Version Oswestry Disability Index (p=0.72) and Visual Analogue Score for back pain (p=0.54)and radiating pain to the leg (p=0.26). The radiological fusion rate was 92.8% in the cage group, and 82.6% in the allograft group (p=0.02). At the last follow up, disc height was decreased to 1.5±0.8 mm of the cage group, and 3.0±1.5 mm of the allograft group (p=0.0001). Conclusions: PLIF using cancellous allograft mixed bone marrow has low fusion rate contrast to good clinical results. It is necessary to take a careful selection of the allograft mixed bone marrow for PLIF.

Study Design: Retrospective study. Objectives: To analyze the clinical results of patients who were treated by pedicle screw fixation in osteoporotic spine and suggest the methods for preventing a loss of fixation strength. Summary of Literature Review: There are some methods to decrease failure rate and increase fixation strength in the osteoporotic spine: use bicortical screw, cement augmentation and supporting anterior column by interbody fusion using cages. Materials and Methods: Forty-four patients treated by spinal instrumentation using pedicle screw from 2004 to 2011 were followed for at least 12 months. Five men and 39 women were diagnosed as osteoporotic spine (T score <-3.0). Two hundred forty eight pedicle screws were included and statistically analyzed the correlation between the use of bicortical screw, cement augmentation, anterior column support and fixation loss of the pedicle screw. Radiologic results were evaluated to find out the mechanical complications, like loosening of the screw, fixation failure, and nonunion. Results: There were 9 complications associated with mechanical strength, loosening of pedicle screws in 7, sinking down of cage in 4, and nonunion in 4 cases. Using bicortical pedicle screw, cement augmentation and anterior column support were significantly correlated with the increasing fixation strength (P=0.001, P=0.047, P=0.014). In addition, these three factors contribute to stabilize the instrumentation (Linear by linear association, P=0.012). Conclusions: These 3 methods, using bicortical pedicle screw, cement augmentation and supporting anterior column, are effective to enhance the fixation strength and prevent loss of holding power in the osteoporotic spine.

Study Design: Prospective study. Objectives: To define the prognostic factors by analyzing the survival rates of osteoporotic vertebral fracture treated by conservative management. Summary of Literature Review: Due to an increasing elder population, many recent studies of osteoporosis have been done; pointing out that osteoporotic vertebral fracture may produce serious complications. However, there is nothing obviously demonstrated in both the management and prognosis of the osteoporotic vertebral fracture. Materials and Methods: Survival analysis was done for 130 patients who had undergone conservative management for a single level vertebral fracture. Univariant and multivariant survival analysis was done for age at trauma, sex, body mass index (BMI), bone mineral density (BMD), smoking, diabetic history, fracture level, fracture type, vertebral compression ratio and regional Cobb’s angle. Results: Survival rate for conservative management was 70.7%. Univariant analysis for survival rate revealed significantly inferior results for age over 78 (p=0.008), T score< -3.5 (p=0.047), and crush or biconcave type than wedge type (p=0.021). Only the age factor showed significance in multivariant analysis (p=0.025, Hazard ratio=2.08). Conclusion: Conservative management in a single level osteoporotic vertebral fracture, showed a survival rate of 70.7% and age was the most important factor in conservative management. We should notice that age of more than 78 years is at high risk for failure in conservative management of vertebral fracture.

Study Design: Retrospective review and radiological analysis. Objectives: We investigated whether the lumbosacral sagittal curvature have any relation to the patterns of lumbar disc degeneration. Summary of Literature Review: Recently, there have been many studies on the correlations between the changes of lumbar disc degeneration and associated factors, such as age, gender, weight, occupation, cigarette smoking, and genetics; but, it is hard to find research into lumbosacral sagittal alignments. Materials and Methods: This study enrolled 117 young adult patients limited by age (18-35 years), BMD (<30kg/m2), no smoking,occupation except heavy worker, no prior lumbar surgery and no combined spinal deformity. By measuring the pelvic incidence, sacral slope, lumbar tilt angle, lumbar lordosis and lumbar axis indicating the parameters of sagittal alignments, we investigated the correlation between the number and severity of lumbar disc degeneration and the number of herniated intervertebral discs. Results: This study found a moderate correlation between pelvic incidence, sacral slope, lumbar lordosis, and the number of lumbar degenerative disc (r =-0.451, p <0.001; r =-0.433, p <0.001; r =-0.425, p <0.001). We calculated the most proper cut-off value of pelvic incidence associated with more than three segments of multiple lumbar disc degeneration, using a minimum p-value approach. Conclusions: As pelvic incidence, sacral slope, and lumbar lordosis indicating the parameters of lumbosacral sagittal alignments get smaller, the numbers of lumbar disc degenerations and herniated intervertebral discs increase. When pelvic incidence is below 45.6degrees, it is more likely for degenerative changes of lumbar disc to affect more than three segments.

Study Design: This study intended to find out differences of effects by axial loading in MRI examination in a patient group with neurologic claudication and a group without neurologic claudication Objectives: It was intended to understand in which group the effects of axial loading can be expected when taking MRI on the lumbar spine. Summary of Literature Review: The study of Willen and Danielson found spinal canal stenosis, which cannot be found by existing methods comparing an MRI taken in bended posture of lumbar without axial loading implementation by MRI taken with axial loading implementation. Hiwatashi et al. also reported that there was a change of treatment direction by laminectomy after axial loading in patients who were intended to take a conservational treatment before the axial loading. Materials and Methods: A total of 39 patients and 54 intervertebral discs were compared. The distances from a sagittal plane before and after intervertebral discs were compared by measuring a sectional area of dura mater in a horizontal plane image and two groups were compared by existence of patients’ neurologic claudication. Results: The AP diameter before and after a intervertebral discs increased into 41.98 mm from 41.1 mm on the average and the sectional area of dura mater showed 137.47mm2 before loading and 119.86mm2 after loading on the average. There was not a significant difference in the distances before and after axial loading implementation, but a significant difference was found in the sectional area of dura mater. Conclusion: Axial loading would contribute to diagnose spinal disease, and especially, spinal canal stenosis in a patient group with claudication.

Study Design: Retrospective study. Objectives: To demonstrate the fusion rate, degree of subsidence and donor site morbidity of anterior cervical interbody fusion with autogenous bicortical iliac bone graft and anterior cervical locking plate. Summary of Literature Review: In anterior cervical discectomy and fusion with autogenous tricortical iliac bone graft, a large percentage of patients report chronic donor site pain. Materials and Methods: Retrospective research was done for 39 patients who underwent anterior cervical interbody fusion with autogenous bicortical iliac bone graft, from January 2006 to July 2011, with a follow up period of longer than 1 year. Fusion rates and subsidece of the graft is estimated with radiographs. Neck pain and donor site pain was estimated with visual analogue scale (VAS) and dysfunction was estimated with the neck disability index (NDI). Results: A 95% of patients who underwent anterior cervical interbody fusion with autogenous bicortical iliac bone graft revealed definitive fusion with little amount of subsidence. The mean VAS score was 0.7 on the donor site and the mean NDI score was 3.8 at the final visit. There was excellent clinical outcome without complication at the donor site or the recipient site. Conclusions: Anterior cervical interbody fusion with autogenous bicortical iliac bone graft showed high fusion rates and minimal subsidence with excellent clinical outcomes. Therefore, bicortical iliac bone graft is an effective operational procedure in anterior cervical interbody fusion.

Study Design: Level III, retrospective studies. Objectives: This study is conducted to evaluate the effect and usefulness of ultrasound guided facet block for the outpatients who complained of chronic lower back pain. Summary of Literature Review: Facet joint syndrome was introduced in 1976, by Mooney V. It was considered to be one of the major causes of low back pain. Materials and Methods: Between October 2009 to March 2011, 98 cases were selected from the outpatients who complained of chronic lower back pain for more than 3 months. The patients had no surgery history and did not complain of neuromuscular symptoms, and they had more than three times outpatient care at least and could be followed up for 1 year. The patients were divided into three groups; first was the ultrasound guided facet block group (27 cases), second was the Fluoroscopy guided facet block group (39cases) and third was the conservative group (32 cases).The clinical results were analyzed using Kim’s criteria and the Visual Analog Scale score, ODI score, Physician’s global assessment (subjective), Patient’s global assessment (Objective). Results: The VAS score was improved from an average of 7.75±1.5 to 4.47±2.4 in the ultrasound guided facet block group, and from 7.81±1.4 to 4.39 ±2.6 in the Fluoroscopy guided facet block group, and from 7.87±1.3 to 6.24±2.1 in the conservative group. The VAS score, Kim’s criteria, ODI score, Physician’s global assessment (subjective), and Patient’s global assessment (Objective) showed statistically significant improvement in the ultrasound guided facet block group and Fluoroscopy guided facet block group. Conclusion: In the outpatient clinics, comparing with the group that underwent conservative treatment with medication, the group treated with ultrasound for block could have better results in clinical improvement.