Modified Tap-drilling Technique for Mid-cervical Pedicle Screw Placement: A Case Series of 473 Consecutive Screws.

STUDY DESIGN: Retrospective cohort study. OBJECTION: To report our modified tap-drilling technique for mid-cervical pedicle screw placement and to evaluate its safety and accuracy. SUMMARY OF BACKGROUND DATA: Cervical pedicle screw fixation, which provides a strong stabilization, has been a major concern due to the potential risks to neurovascular structures despite its increasing use. Several insertion techniques have been described so far to improve the cervical pedicle screw placement accuracy. METHODS: This study retrospectively reviewed patients who underwent mid-cervical (C3-C6) pedicle screw fixation between September 2005 and September 2020. Laminectomy, laminoforaminotomy, or notch-referred anatomic landmark methods were used to adjust the entry point and the direction of the screws. After the cortical bone was removed at the entry point with a diamond burr, the cancellous bone was slowly drilled with a hand drill starting from 8 to 10 millimeters in length. Then, all of the bone walls were checked with a ball-tip probe to determine if there was any breach. The procedure was repeated several times. After completing the drilling, the screw was inserted without tapping. The breach rate of pedicle screws was analyzed on postoperative computed tomography scans. RESULTS: A total of 473 mid-cervical pedicle screws were placed in 122 consecutive patients. No navigation or computer-assisted system was used, and the first 2 authors inserted all of the screws. All patients completed the surgery, and no evident intraoperative complications occurred. Postoperative CT scans were obtained for 405 screws. Although deviation was observed for 131 pedicle screws, a critical deviation was observed for only 25 pedicle screws. CONCLUSIONS: Cervical pedicle screw insertion is a risky but applicable technique. Checking all of the bone walls with a ball-tip probe before gradually advancing the hand drill in small amounts, as presented in this article, may lead to the safe and effective placement of cervical pedicle screws.

Ependymomas of the spinal region in adults: Clinical and pathological features and MYCN expression levels in spinal ependymomas and myxopapillary ependymomas.

BACKGROUND: Ependymomas (EPNs) of the spinal region are a heterogeneous group of tumors that account for 17.6 % in adults. Four types have been recognized: subependymoma, spinal ependymoma (Sp-EPN), myxopapillary ependymoma (MPE), and Sp-EPN-MYCN amplified, each with distinct histopathological and molecular features. METHODS: This study investigated the clinical and pathological characteristics and MYCN expression levels of 35 Sp-EPN and MPE cases diagnosed at a tertiary university hospital over a decade-long period. RESULTS: Twenty-five cases were Sp-EPN and 10 cases were MPE, and were graded as WHO grade 2, except for 1 Sp-EPN case with grade 3 features. The most common symptoms were lower back pain and difficulty in walking. Radiology showed different tumor sizes and locations along the spinal cord, with MPEs exclusively in the lumbosacral region. Surgery was the main treatment, and gross total resection was achieved in all cases except for one. Immunohistochemistry showed low Ki-67 proliferation indices in all cases, and no MYCN expression. During follow-up, 3 (8.6 %) cases recurred and/or metastasized and 5 cases (14.3 %) died. No significant difference was found in disease-free survival or overall survival between Sp-EPN and MPE cases. However, 3 cases with grade 2 histology demonstrated recurrence and/or metastasis, despite the lack of MYCN expression. CONCLUSION: Our results underscore the multifactorial nature of tumor aggressiveness in EPNs of the spinal region. This study enhances our knowledge of the clinical and pathological features of Sp-EPNs and MPEs and highlights the need for better diagnostic and prognostic markers in these rare tumors.

A case of rare lumbar intradural tumor: paraganglioma.

Lumbar paragangliomas are rare neuroendocrine neoplasms arising from specialized neural crest cells in the cauda equina/filum terminale region. They are difficult to diagnose radiologically and can be difficult to treat surgically if they secrete catecholamines. A 38-year-old woman presented with three and a half years of increasing lower back and sacrum discomfort. Her neurological examination was normal. The MRI revealed an L4 intradural lesion that was compressing the cauda equina. A total tumor resection was conducted. The paraganglioma was diagnosed by the pathology report. Paragangliomas should be considered in the differential diagnosis of intradural masses of the lumbar spine.

Evaluation of Incidentally Detected Pathology Results of Patients with Vertebral Fracture Treated by Vertebroplasty and Kyphoplasty: A Retrospective Study.

BACKGROUND: Vertebroplasty and kyphoplasty are minimally invasive techniques used to treat vertebral compression fractures. The etiology of vertebral compression fractures varies among patients. Although osteoporosis and trauma are major etiologic factors in patients with a vertebral compression fracture, unexpected results were found in 11 patients in the present study. The aim of the present retrospective study was to determine the incidentally detected pathology results of patients with vertebral fracture treated by vertebroplasty and kyphoplasty. METHODS: From February 2010 to November 2015, 616 patients with a vertebral compression fracture were treated by kyphoplasty and vertebroplasty at our institution. Vertebral biopsies were obtained from 533 patients during a vertebral augmentation technique. The average patient age was 62.4 years. Of the 616 patients, 388 were female and 228 were male. Histological evaluation of the biopsy specimens from the vertebral compression fractures was performed. RESULTS: The biopsy results of 505 patients showed various stages of bone healing. Among these patients, malignancy was identified in 23 patients, and 43 patients had a history of malignancy. In 6 patients, an unsuspected malignancy was found, and 1 patient had Paget's disease. Infection was detected in 4 patients. In our study, the rate of unsuspected malignancy was 1.1%. CONCLUSIONS: Tissue examination is useful and could reveal pathologic fractures. An incidentally detected biopsy result could change the treatment of patients; however, bone biopsy should be reserved for those patients whose preoperative radiological diagnosis raises suspicion of a nonosteoporotic etiology.

Neuroprotective Effect of Resveratrol on Acute Brain Ischemia Reperfusion Injury by Measuring Annexin V, p53, Bcl-2 Levels in Rats.

BACKGROUND: Cerebral ischemia is as a result of insufficient cerebral blood flow for cerebral metabolic functions. Resveratrol is a natural phytoalexin that can be extracted from grape's skin and had potent role in treating the cerebral ischemia. Apoptosis, a genetically programmed cellular event which occurs after ischemia and leads to biochemical and morphological changes in cells. There are some useful markers for apoptosis like Bcl-2, bax, and p53. The last reports, researchers verify the apoptosis with early markers like Annexin V. METHODS: We preferred in this experimental study a model of global cerebral infarction which was induced by bilateral common carotid artery occlusion method. Rats were randomly divided into 4 groups : sham, ischemia-reperfusion (I/R), I/R plus 20 mg/kg resveratrol and I/R plus 40 mg/kg resveratrol. Statistical analysis was performed using Sigmastat 3.5 ve IBM SPSS Statistics 20. We considered a result significant when p<0.001. RESULTS: After administration of resveratrol, Bcl-2 and Annexin levels were significantly increased (p<0.001). Depending on the dose of resveratrol, Bcl2 levels increased, p53 levels decreased but Annexin V did not effected. P53 levels were significantly increased in ishemia group, so apoptosis is higher compared to other groups. CONCLUSION: In the acute period, Annexin V levels misleading us because the apoptotic cell counts could not reach a certain level. Therefore we should support our results with bcl-2 and p53.

Prevention of anterior scar formation following discectomy with a MediShield adhesion barrier: randomized experimental trial.

AIM: To investigate whether carboxymethylcellulose/polyethylene oxide (CMC/PEO) gel has a protective effect against epidural scar formation anterior to the dura following discectomy. MATERIAL AND METHODS: A barrier gel comprised of CMC and PEO (MediShield) was studied as a material to reduce anterior epidural scar formation in a rabbit laminotomy and discectomy model. After laminotomy and disc puncture, the surgical side was either treated with MediShield or used as a surgical control, as determined by random allocation. Two months after surgery, the animals were euthanized, and their lumbar spines were removed in an en bloc excision for pathological evaluation. Scar formation was evaluated as present or absent. RESULTS: The MediShield group contained 12 rabbits, and the control group contained 7 rabbits. Epidural fibrosis was observed in two out of twelve specimens (17%) in the MediShield group and in three of seven (43%) cases in the control group (P=0.305, Fisher's Exact Test). CONCLUSION: Though it was not statistically significant, we observed a difference between the MediShield and control group that favored the MediShield group. The application of the CMC/PEO gel might protect against epidural fibrosis after lumbar discectomy, but its efficacy needs to be investigated in larger experimental trials.

Primary spinal epidural Hodgkin's lymphoma.

Primary spinal epidural Hodgkin's lymphoma is very rare. We will discuss the clinical features and treatment of primary spinal epidural Hodgkin's lymphoma. In this paper, a 30-year-old male patient who presented with spinal epidural tumor at the T9-11 level is reported. Subtotal resection of the tumor was performed and the histological examination of the tumor specimen revealed Hodgkin's lymphoma. All other examinations were negative for an occult disease. Six courses of chemotheraphy containing adriamycin, bleomycin, vinblastine and dacarbazine were given to the patient. Surgery is the first therapeutic approach in malignancies compressing the spinal cord. Hodgkin's lymphoma is a very chemo- and radio-sensitive tumor. The indications for surgery were reduced and limited to laminectomy or even biopsy only, leaving the major role to chemo- and radiotheraphy.