2012, Vol.19, No.4

Journal of Korean Society of Spine Surgery 2023 KCI Impact Factor : 0.03

pISSN : 2093-4378 / eISSN : 2093-4386
https://journal.kci.go.kr/krspine

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.