Percutaneous discectomy-continuous irrigation and drainage for tuberculous lumbar spondylitis: a report of two cases.

Percutaneous curettage and continuous irrigation were performed for definitive diagnosis and treatment of tuberculous (TB) lumbar spondylitis. Under local anaesthesia, affected lumbar discs were curetted using a procedure of percutaneous nucleotomy, and in-tube and the out-tube were placed for continuous irrigation. The period of continuous irrigation was 12-16 days. Mycobacterium tuberculosis was demonstrated in case 1 by culture and PCR, whereas histology showed tuberculous lesion with caseous necrosis in both cases. Postoperative MRI showed markedly reduced abscesses after 3 months in both cases. The signal intensity in vertebral bodies was improved. In Case 2, CT observations showed remodeling over time in the vertebral body cavities. This method is advantageous in that although minimally invasive, it achieves identification of pathogenic bacteria and treatment simultaneously. This surgical procedure is expected to prove effective for both TB and pyogenic spondylitis.

Percutaneous curettage and continuous irrigation for MRSA lumbar spondylodiscitis: a report of three cases.

There has been a recent increase in pyogenic spondylitis caused by methicillin-resistant Staphylococcus aureus (MRSA) associated with an increasing number of compromised patients. As long as serious paralysis is absent, we recommend percutaneous curettage and continuous irrigation as an effective treatment for MRSA lumbar spondylodiscitis. Under local anesthesia, the affected lumbar discs were curetted using percutaneous nucleotomy, and tubes were placed for continuous irrigation. The period of continuous irrigation was generally 2 weeks. Infection was controlled after one procedure in two cases and after two procedures in one case. Postoperative radiography and magnetic resonance imaging (MRI) showed callus formation, normalized signal intensity in vertebral bodies, and regression of abscesses. Open surgery under general anesthesia has been considered risky in patients with poor performance status or old age. The present method, which is an application of needle biopsy, can be performed under local anesthesia and is minimally invasive.

Clinical outcomes of percutaneous curettage and continuous irrigation for pyogenic spondylitis.

BACKGROUND: Several recent studies have reported percutaneous curettage and continuous irrigation as effective treatments for pyogenic spondylitis. However, factors affecting the normalization of CRP levels remain unclear. This retrospective study investigated the clinical outcomes of percutaneous curettage and continuous irrigation for pyogenic spondylitis, and factors affecting the duration until normalization of CRP levels. METHODS: Subjects comprised 16 patients who underwent percutaneous curettage and continuous irrigation for pyogenic spondylitis. Patients were divided into 3 groups according to duration from surgery until normalization of CRP levels to 6 weeks. Clinical and radiographic findings were compared between groups. RESULTS: Japanese Orthopaedic Association score was improved in all patients within 2 weeks after surgery. Preoperative CRP level was lower in the early group (0.55 +/- 0.27 mg/dL) compared with the middle (2.63 +/- 1.84 mg/dL; P < .05) and delayed groups (7.59 +/- 10.44; P < .05). Duration of irrigation was shorter in the delayed group (10.7 +/- 3.7 days) compared with the early (15.6 +/- 2.0 days; P < .05) and middle groups (15.5 +/- 3.0 days; P < .05). Findings on MRI improved within 2 months in the early and middle groups. CONCLUSIONS: This treatment is minimally invasive and useful in patients with pyogenic spondylitis. Lower CRP level before surgery and longer duration of irrigation may reduce the duration to normalization of CRP level.

Glial and axonal regeneration following spinal cord injury.

Spinal cord injury (SCI) has been regarded clinically as an irreversible damage caused by tissue contusion due to a blunt external force. Past research had focused on the analysis of the pathogenesis of secondary injury that extends from the injury epicenter to the periphery, as well as tissue damage and neural cell death associated with secondary injury. Recent studies, however, have proven that neural stem (progenitor) cells are also present in the brain and spinal cord of adult mammals including humans. Analyses using spinal cord injury models have also demonstrated active dynamics of cells expressing several stem cell markers, and methods aiming at functional reconstruction by promoting the potential self-regeneration capacity of the spinal cord are being explored. Furthermore, reconstruction of the neural circuit requires not only replenishment or regeneration of neural cells but also regeneration of axons. Analysis of the tissue microenvironment after spinal cord injury and research aiming to remove axonal regeneration inhibitors have also made progress. SCI is one of the simplest central nervous injuries, but its pathogenesis is associated with diverse factors, and further studies are required to elucidate these complex interactions in order to achieve spinal cord regeneration and functional reconstruction.

Expression and role of type I collagen in a rat spinal cord contusion injury model.

To verify the expression of type I collagen after SCI and discuss its role and cellular origin, a standardized animal model of contusive spinal cord injury (SCI) was analyzed. Male Sprague-Dawley rats were injured at T11/12 and sacrificed at 1, 4 and 8 weeks after injury. The spinal cord was removed en block for both Western blotting and RT-PCR in order to verify expression of type I collagen. For immunohistological examination, those sections were stained with anti-type I collagen, RECA-1 and anti-rat prolyl-4-hydroxylase. Double-labeling immunohistochemistry was performed using anti-type I collagen and RECA-1. Those sections were examined with an electron microscope. Western blots for type I collagen were positive, as was the gene expression of type I collagen mRNA. Type I collagen after SCI was observed around blood vessels in the ventral white matter of the spinal cord 4 weeks after injury in double-labeling immunohistological examination and electron microscopic images. Immunohistochemical expression of fibroblast was increased 4 weeks after injury. This study revealed the post-SCI expression of type I collagen around blood vessels. Type I collagen may play a role in angiogenesis after SCI. Fibroblasts may produce type I collagen in rat spinal cord.

Tumoral calcinosis in bilateral facet joints of the lumbar spine in scleroderma. Case report.

Tumoral calcinosis commonly occurs in the articular soft tissues of the extremities but rarely in the spine. The authors performed surgery to treat lumbar tumoral calcinosis in a patient with scleroderma, in whom symptoms of neurological dysfunction had manifested. This 49-year-old woman presented with low-back pain and gait disturbance. Seven years before presentation, scleroderma had been diagnosed, and the patient had received medical treatment ever since. Imaging revealed tumoral calcinosis centered at the bilateral facet joints between L-3 and L-4, marked stenosis of the spinal canal, L-3 spondylolisthesis, and intervertebral instability. Surgery was performed to excise the lesion en bloc. After neural decompression, posterolateral fusion and pedicle screw fixation were undertaken. Symptoms improved after surgery. In this case, the underlying scleroderma that predisposes to calcinosis and facet joint degeneration due to lumbar spondylolisthesis were probably factors leading to the development of tumoral calcinosis in the lumbar spine.

Remarkable reduction or disappearance of retroodontoid pseudotumors after occipitocervical fusion. Report of three cases.

Retroodontoid or periodontoid pseudotumor unassociated with rheumatoid arthritis or hemodialysis is clinically rare. The authors report three cases of retroodontoid pseudotumor that they treated surgically. All patients exhibited myelopathy of the upper cervical spinal cord. Plain radiography depicted atlantoaxial instability in two of the three patients. Spinal cord compression caused by a mass lesion in all patients was clearly demonstrated on magnetic resonance images. In two patients, the mass lesion was not limited to the retroodontoid region and expanded continuously to the cranial base. Posterior laminectomy of the atlas and occipitocervical fusion were performed. After surgery, the pseudotumor disappeared in two cases and was clearly reduced in one case, and neurological symptoms also improved. Retroodontoid pseudotumor is a lesion for which symptomatic improvement can be expected with posterior decompression and fusion, even without direct tumor excision.

Different expression of macrophages and microglia in rat spinal cord contusion injury model at morphological and regional levels.

Macrophages and microglia are implicated in spinal cord injury, but their precise role is not clear. In the present study, activation of these cells was examined in a spinal cord injury model using 2 different antibodies against ED1 clone and ionized calcium binding adaptor molecule 1 (Iba1). Activation was observed at 1, 4, 8, and 12 weeks after contusion injury and was compared with sham operated controls. Our results indicate that activation could be observed in both the dorsal funiculus and the ventral white matter area in the spinal cord at 5 mm rostral to the epicenter of injury. For both cells, there was a gradual increase in activation from 1-4 weeks, followed by down-regulation for up to 12 weeks. As a result, we could stain macrophages by ED1 and microglia by Iba1. We concluded that macrophages may play a role in the phagocytosis of denatured dendrites after spinal cord injury, while microglia may have some cooperative functions, as they were found scattered near the macrophages.

Co-expression of radial glial marker in macrophages/microglia in rat spinal cord contusion injury model.

Macrophages/microglia are implicated in spinal cord injury but their precise role in the process is not clear. Our previous studies have reported that radial glia (RG) possess properties of neural stem cells and remerged after central nervous system (CNS) injury which may play an important role in neural repair and regeneration. In the present study, we examined the expression of ED1 (a specific marker for activated macrophages/microglia) and RG in a spinal cord injury (SCI) model and detected the activation at 1, 4, 8, and 12 weeks in both dorsal funiculus and ventral white matter after SCI. For both ED1-positive cells and RG cells, there was a gradual increase in density and in number from 1 to 4 weeks followed by down-regulation up to 12 weeks after injury. The morphologies of macrophages and radial glia were different. However, some ED1-positive cells were also stained by RG marker. These results suggest that macrophages may have some lineage to radial glial cells.

Increase of NG2-positive cells associated with radial glia following traumatic spinal cord injury in adult rats.

In the CSN including the spinal cord, NG2 proteoglycan is a marker of oligodendrocyte progenitors. To elucidate the dynamics of the endogenous neural stem (progenitor) cells in adult rats with spinal cord injury (SCI), we examined an immunohistochemical analysis of NG2, GFAP, and 3CB2, a specific marker of radial glia (RG). SD rats were divided into a SCI group (n = 25) and a sham-operated group (n = 5). In the injury group, laminectomy was performed at Th11-12 and contusive compression injury was created by applying a weight of 30 g for 10 min. Rats were sacrificed at 24 h, and 1, 4, 8 and 12 weeks post-injury. Frozen 20-mu m sections of tissue 5 and 10 mm rostral and caudal to the epicenter of injury were prepared. Immunohistochemistry was performed using antibodies against NG2, GFAP and 3CB2. At 4 weeks after injury, NG2-positive glial cells arose from below the pial surface as bipolar cells with processes extending throughout the entire white matter. NG2 expression peaked at 4 weeks after injury, showing a 7-fold increase compared to the 24 h after injury. The NG2-positive cells with processes which increased in the white matter of the spinal cord were GFAP-positive and also co-localized with 3CB2 antigen. The pattern of NG2 expression of these cells was temporally and spatially different from the pattern of NG2 expression that accumulated around the hemorrhagic and necrotic epicenter. These results suggest that NG2 positive cells which derived from subpial layer, may have some lineage to RG after SCI in adult rodents.

Temporal progressive antigen expression in radial glia after contusive spinal cord injury in adult rats.

In the development of the CNS, radial glial cells are among the first cells derived from neuroepithelial cells. Recent studies have reported that radial glia possess properties of neural stem cells. We analyzed the antigen expression and distribution of radial glia after spinal cord injury (SCI). Sprague-Dawley rats had a laminectomy at Th11-12, and spinal cord contusion was created by compression with 30 g of force for 10 min. In the injury group, rats were examined at 24 h and 1, 4, and 12 weeks after injury. Frozen sections of 20-microm thickness were prepared from regions 5 and 10 mm rostral and caudal to the injury epicenter. Immunohistochemical staining was performed using antibodies to 3CB2 (a specific marker for radial glia), nestin, and glial fibrillary acidic protein (GFAP). At 1 week after injury, radial glia that bound anti-3CB2 MAb had spread throughout the white matter from below the pial surface. From 4 weeks after injury, 3CB2 expression was also observed in the gray matter around the central canal, and was especially strong around the ependymal cells and around blood vessels. In double-immunohistochemical assays for 3CB2 and GFAP or 3CB2 and nestin, coexpression was observed in subpial structures that extended into the white matter as arborizing processes and around blood vessels in the gray matter. The present study demonstrated the emergence of radial glia after SCI in adult mammals. Radial glia derived from subpial astrocytes most likely play an important role in neural repair and regeneration after SCI.