kaolinite and Scoliosis

Scoliosis is often associated with syringomyelia (SM). As an important role in SM formation, the influence from abnormal cerebrospinal fluid (CSF) flow is still unclear to scoliosis. The aim of this experimental work is to explore the connection between CSF flow and scoliosis through imaging and histological analysis on the basis of a kaolin-induced scoliotic rabbit model. For imaging observation, in 40 kaolin-induced rabbits by C7 spinal cord injection, through pre- and postoperative MRI and radiography, CSF flow and scoliosis formation were detected at consecutive phases. According to the final formation of scoliosis until postoperative week 12, the kaolin-induced rabbits were divided into 2 groups. Through comparing the 2 groups, the relationship between the changes of CSF flow velocity and scoliosis formation were reviewed and analyzed. For histological observation, another 20 kaolin-induced rabbits were used for consecutive histological observations of spinal cord at postoperative 3-day, 2-week, 4-week and 6-week. After kaolin-induction, abnormal spinal coronal curve was observed from postoperative week 6 in the 37 survived rabbits. At postoperative week 12, scoliosis formation was detected in 73.0% kaolin-induced rabbits and the mean Cobb angle was 27.4°. From the comparison between scoliotic and non-scoliotic groups, the difference of the velocities of CSF flow was more obviously from postoperative week 4 to 12, especially after week 6. In the scoliotic group, the peak velocity of CSF flow was diseased gradually following scoliosis formation after induction. Moreover, the decrease of the peak velocities of CSF flow from preoperation to postoperative 12 weeks (ΔVmax), including up-flow (ΔVUmax) and down-flow (ΔVDmax), were positively correlated to the final scoliotic Cobb angle (P < 0.01). Through histological observation at different phases, the distinctive pathological changes of the spinal cord included early inflammatory reaction, adhesion and blockage in the subarachnoid space and the central canal, perivascular space enlargement, central canal expansion, which suggested the CSF flow being blocked by multiple ways after kaolin-induction. In conclusion, experimental scoliosis can be successfully induced by intraspinal kaolin injection. In this model, continuous hypodynamic change of CSF flow was correlated to the formation of scoliosis, which could be an important factor of scoliotic pathogenesis being explored furtherly.

Topics: Animals; Kaolin; Magnetic Resonance Imaging, Cine; Postoperative Period; Rabbits; Rheology; Scoliosis; Spine

Retrospective case-control study.. To evaluate the hemostatic benefits of using a kaolin-impregnated dressing during pediatric spinal deformity correction surgery.. Minimizing blood loss and transfusions are clear benefits for patient safety. A technique common in both severe trauma and combat medicine that has not been reported in the spine literature is wound packing with a kaolin-impregnated hemostatic dressing.. Estimated blood loss and transfusion amounts were analyzed in a total of 117 retrospectively identified cases. The control group included 65 patients (46 females, 19 males, 12.7±4.5 yr, 10.2±4.8 levels fused) who received standard operative care with gauze packing between June 2007 and March 2010. The treatment group included 52 patients (33 females, 19 males, 13.9±3.2 yr, 10.4±4.3 levels fused) who underwent intraoperative packing with QuikClot Trauma Pads (QCTP, Z-Medica Corporation) for all surgical procedures from July 2010 to August 2011. No other major changes in the use of antifibrinolytics or perioperative, surgical, or anesthesia technique were noted. Statistical differences were analyzed using analysis of covariance in R with P value of less than 0.05. The statistical model included sex, age, weight, scoliosis type, the number of vertebral levels fused, and surgery duration as covariates.. The treatment group had 40% less intraoperative estimated blood loss than the control group (974 mL vs. 1620 mL) (P<0.001). Patients who received the QCTP treatment also had 42% less total perioperative transfusion volume (499 mL vs. 862 mL) (P<0.01).. The use of a kaolin-impregnated intraoperative trauma pad seems to be an effective and inexpensive method to reduce intraoperative blood loss and transfusion volume in pediatric spinal deformity surgery.. 3.

Topics: Adolescent; Bandages; Blood Loss, Surgical; Blood Transfusion; Child; Cost Savings; Female; Hemostatic Techniques; Hemostatics; Hospitals, Pediatric; Humans; Intraoperative Care; Kansas; Kaolin; Male; Retrospective Studies; Scoliosis; Spinal Fusion; Surgical Sponges; Tertiary Care Centers

Post-traumatic cystic changes in cerebrospinal fluid (CSF) pathways such as ventriculomegaly and/or hydrosyringomyelia are not uncommon, but their characteristics have not yet been fully clarified. This study was designed to investigate the alterations affecting the CSF pathways in rabbits at a late stage, and to clarify the relationship between these changes and the development of spinal deformity. In this study, a total of 60 New Zealand white rabbits were used and they were segregated into four different groups of 15 animals each: sham-operation group, kaolin group, and kaolin plus mild trauma group and kaolin plus severe trauma group. The animals were subjected to radiological investigation using direct X-ray study and magnetic resonance imaging (MRI) after 4 months. The thoracic spinal cords of the animals were dissected after intracardiac perfusion-fixation with 10% formalin for light microscopy and 2.5% glutaraldehyde for transmission electron microscopic study. Following the sectioning and staining procedures, the histological characteristics of the spinal cords were evaluated with light microscopy and transmission electron microscopy. A spinal deformity developed in 90% in rabbits in both kaolin injection group and spinal trauma groups. MRI revealed generalized dilatation of the ventricular system and the central canal of the spinal cord after the kaolin injection with/without trauma in this study. Gross morphologic examination showed some enlargement of entire CSF pathways in these groups. All animals with central canal dilatation had mild or severe scoliotic and kyphotic deformities. In a light microscopic study, a denuded ependymal line and multicyst formations in periependymal areas were found in both kaolin injection and spinal trauma groups. Ultrastructurally, an apical flattening of the ependyma, microcysts in the ependymal cells, axonal degeneration, demyelination, and loss of ependymal cells adjacent mild spongy were found in the spinal cords of animals in these groups. To the best of our knowledge, this is the first study to investigate the chronic effects of spinal cord injury (SCI) on the CSF pathways and their relationship with the development of spinal deformity in an experimental model of kaolin injection and trauma, using MRI as well as light and transmission electron microscopy. In the light of this study, the severity of spinal cord injury on the development of some degenerative findings in the spinal cord was clear, but further

Topics: Animals; Autopsy; Brain; Cerebrospinal Fluid; Injections; Kaolin; Kyphosis; Magnetic Resonance Imaging; Male; Microscopy, Electron; Rabbits; Radiography; Scoliosis; Spinal Canal; Spinal Cord; Spinal Cord Injuries; Subarachnoid Space; Survival Analysis

Animal scoliosis model associated with syringomyelia.. To investigate the pathogenesis of scoliosis produced in dogs with kaolin-induced syringomyelia.. Kaolin injected into the cisterna magna produces basilar arachnoiditis, leading to hydrocephalus and syringomyelia. There have been no reports on scoliosis associated with kaolin-induced syringomyelia.. Kaolin was injected percutaneously into the cisterna magna of 11 beagles 6-8 weeks after birth. Roentgenograms, computed tomography, and magnetic resonance imaging were obtained. The spinal cord and the paraspinal muscles were examined histologically. Structural changes of the vertebral column were analyzed with calcein and tetracycline labeling.. Hydrocephalus occurred in nine dogs. A communicating syringomyelia appeared in five dogs. Mild scoliosis developed in two dogs, and severe cervical scoliosis in one dog. In the syringomyelia cases, acute or subacute inflammatory changes were found in the spinal cord. Damage of the anterior and posterior horn cells was more marked in the scoliotic animals than in the nonscoliotic animals. In three of the syringomyelia cases, including two scoliosis cases, the paraspinal muscles revealed neurogenic changes. The deformed vertebrae appeared to diminish rather than to increase the deformity in severe scoliosis.. The exact mechanism of the development of scoliosis could not be identified, although an etiologic relation with malfunction of the central nervous system was noted. This model may be useful to study scoliosis experimentally.

Topics: Animals; Cisterna Magna; Disease Models, Animal; Dogs; Injections; Kaolin; Magnetic Resonance Imaging; Muscle, Skeletal; Radiography; Scoliosis; Spinal Cord; Spine; Syringomyelia