logo
    rhBMP-2 enhancement of posterolateral spinal fusion in a rabbit model in the presence of concurrently administered doxorubicin
    13
    Citation
    24
    Reference
    10
    Related Paper
    Citation Trend
    Iliac crest wedges are commonly used in spinal fusion procedures and must be capable of withstanding considerable mechanical stress during the healing process. Physical parameters, mechanical properties, correlations among physical parameters, and correlations of mechanical properties versus physical parameters have been presented by the authors in companion papers. In this study, mathematical formulas have been developed, using multi-variable regiression analysis, which permit calculation of the axial load-bearing capacity and comprassive strength of a wedge, provided donor age, cortical bone coross-sectional area, total corss-sectional area, and wedge “width” are available. The formulas proposed are simple, easy to use, and provide acceptable accuracy. For the predicted load-bearing capacity, experimentally determined data illustrated that 59% of the calculated values had either less than 10% error or their predicted values were smaller than the observed values, 75% of the calculated values had either less than 20% error or their predicted values were smaller than the observed values. Similar accuracies were estimated for calculation of compressive strengths. Charts are genereted from the established formulas, which permit a visual determination of load-bearing capacity and compressive strength of a wedge.
    Iliac crest
    Biomechanics
    Spinal Surgery
    Properly harvested iliac crest bone autograft applied to a meticulously prepared fusion bed produces a consistently high rate of fusion with a low incidence of donor site morbidity. Some reports advocate substituting bone morphogenic protein (BMP) for iliac crest bone autograft, but in posterolateral lumbar spinal fusion, BMP appears better suited to facilitate iliac crest bone autograft maturation than to substitute for it. In this single-center, nonrandomized, prospective study (minimum 2-year follow-up), cancellous-only iliac crest bone autograft was harvested for use in posterolateral lumbar spinal fusion. Reviewers blinded to graft condition and age assigned fusion scores to the random radiographs of 31 consecutive patients who underwent 1- to 3-level posterolateral lumbar spinal fusion using iliac crest bone autograft supplemented with either an implanted spinal fusion stimulator or BMP. There was no significant immediate or remote iliac crest bone autograft harvest morbidity, and there was a significant reduction in pain scores postoperatively ( P <.001). At 12 months, BMP radiographs were more likely than spinal fusion stimulator radiographs to be rated as fused ( P <.019). All BMP patients were deemed fused at 12 months and all spinal fusion stimulator patients at 24 months. In this study, iliac crest bone autograft supplemented with either BMP or spinal fusion stimulator resulted in a solid contiguous fusion without significant iliac crest bone autograft harvest-related morbidity. Bone morphogenic protein-supplemented iliac crest bone autograft fused at a faster rate, producing the more mature-appearing, trabeculated, robust fusion.
    Iliac crest
    Cancellous bone
    Pseudarthrosis
    Study Design. Posterolateral spinal fusion with autologous bone marrow aspirate in addition to autograft iliac crest bone graft in a rabbit model. Objective. To demonstrate that the addition of autologous bone marrow can have positive effects on bone formation and spinal fusion. Summary of Background Data. Bone marrow has been shown to contain osteoprogenitor cells. A number of studies have demonstrated that bone formation is possible with autologous marrow injection into orthotopic sites such as that performed in femur fracture models. Methods. A bone paucity model of posterolateral spine fusion was developed. The control animals received 0.8 g of morselized autogenous iliac crest bone graft harvested from a single iliac crest. The graft was mixed with 2 mL of clotted peripheral blood. In the experimental group, 2 mL of bone marrow aspirated from the opposite iliac crest was substituted for the peripheral blood clot. All rabbits were killed at 12 weeks, and the specimens were subjected to evaluation by posteroanterior radiography for the presence of fusion, computed tomography for bone volume, and biomechanical testing for stiffness. Results. Successful fusion was achieved in 61% of the animals in the experimental group versus 25% in the control group (P < 0.05). The fusion mass in the experimental group had a mean volume of 919 ± 387 mm3versus 667 ± 512 mm3 for the control group, as measured from computed tomography images. The results of the biomechanical testing validated the radiographic scoring system. The stiffness in specimens, graded as having a radiographic score of 4, was significantly greater than in specimens with radiographic scores of 1 and 2. Conclusion. In cases for which an adequate quantity of autogenous bone graft is not available, addition of bone marrow may facilitate greater bone formation and successful fusion.
    Iliac crest
    Bone marrow aspirate
    Background: The line joining the iliac crest superiorly and posteriorly is known as Intercrestal line. Various studies described that it crosses in the midline at L4–L5 intervertebral disc space level. Relationship of spinal level on palpation and imaging the iliac crest intercrestal line is not the same in particular the L4–L5 interspace.Purpose: The purpose of this study is to compare the spinal level identified through palpation and imaging the iliac crest intercrestal line in adults.Materials and Methods: Patients included low back pain undergoing epidural steroid injection at RL Jalappa Hospital and Research Center, between October 2018 to January 2019. Iliac crest posterio-superiorly was palpated by the authors and the intercrestal line was drawn, then followed by imaging, the level of the spine in the midline identified and were recorded and compared.Results: Our study shows that on palpation the L3-4 spinal level in 27 patients (48.2%) and L4 spinal level in 22 patients (39.2%) whereas on imaging the L4 spinal level in 33 patients (58.9%) and L4–5 spinal levels in 21 patients (37.5%), the intercrestal line formed through palpation tended to identify higher levels. On both methods the same level observed in 10.7% (6 patients) only.Conclusion: Palpation and imaging method of iliac crest intercrestal line are the two methods to identify the spinal level. Clinically, the palpation of the intercrestal line to identify the L3–4 and L4 spinal levels rather than the L4 or L4–5 levels, particularly in patients with high BMI (body mass indices).
    Palpation
    Iliac crest