How I do it: cervical lateral mass screw fixation

Background: Cervical lateral mass screw fixation is indicated for the treatment of cervical subaxial C3-C7 lesions associated with instability. Method: The authors first describe the surgical anatomy of the subaxial cervical posterior approach. Then the Magerl technique is detailed. In particular, tricks to avoid complications are presented. The ideal screw entry point, direction, size and exit point are mentioned. A surgical video, artist's drawings and a radiological case report are included. Conclusion: The Magerl technique is a safe and effective lateral mass fixation technique. Respecting anatomical landmarks is crucial to avoid nerve root, vertebral artery and facet joint injur

Cauda equina tumor surgery: how I do it

Background: Tumors of the cauda equina usually require surgery due to their impingement on neighboring nerve roots, often resulting in pain and neurological deficits. Method: The Authors first give a brief introduction on cauda equina tumors, followed by a description of the surgical anatomy, and then develop the microsurgical technique. In particular, tricks to avoid complications are presented, underlining the importance of intraoperative neuromonitoring. Conclusion: Both microsurgical technique and neuromonitoring are important in cauda equina tumor surgery, the goal of which is to achieve complete resection while at the same time preserving neurological functio

Accuracy of freehand fluoroscopy-guided placement of C1 lateral mass and C2 isthmic screws in atlanto-axial instability

Background: The C1 lateral mass and C2 isthmic stabilization, as introduced by Goel and Laheri and by Harms and Melcher, is a well-known fixation technique. We present the clinical and radiographic results with freehand fluoroscopy guided C1 lateral mass and C2 isthmic fixation in a consecutive series of 28 patients, evaluating the accuracy of screw placement. Methods: Twenty-eight consecutive patients suffering from post-traumatic and other C1-C2 instability were operated on between 2001 and 2010. Indications for surgery were: trauma (n = 21 cases), os odontoideum (n = 1), cranio-verterbal malformation (n = 1), and arthritis (n = 3) and idiopathic instability (n = 2). C1 lateral mass and C2 isthmic screws were placed according to the usual anatomical landmarks with lateral fluoroscopy guidance. All patients underwent a postoperative CT scan. The extent of cortical lateral or medial breach was determined and classified as follows: no breach (grade A), 0-2mm (grade B), 2-4mm (grade C), 4-6mm (grade D), more than 6mm (grade E). Grade A and B screws were considered well positioned. Results: A total of 56C1 lateral mass and 55C2 isthmic screws were placed. Accuracy of screw placement was as follows: 107 grade A (96.4%), four grade B (3.6%), and no grade C, D or E. Clinical and radiological follow-up showed improvement in symptoms (mainly pain) and stability of the implants at the end of the follow-up. Conclusions: Freehand fluoroscopy-guided insertion of C1 lateral mass and C2 isthmic screws can be safely and effectively performe

Influence of cytokine inhibitors on concentration and activity of MMP-1 and MMP-3 in disc herniation

INTRODUCTION: Spontaneous resorption of disc herniation (DH) after sciatica is well documented. The matrix metalloproteinases (MMP)-1 and MMP-3 are enzymes potentially involved in this process. Glucocorticoid injections are commonly used for treatment, and other anti-inflammatory molecules like tumor necrosis factor (TNF) inhibitors are under clinical investigation. However, little is known about the effect of these molecules on DH resorption. METHODS: DH tissue was harvested from patients undergoing surgery for sciatica. Samples were thoroughly washed. Diced explants were cultured ex-vivo in 1) 0.5 ml Dulbecco's modified Eagle's medium (DMEM) 10% fetal calf serum (FCS), (controls), 2) recombinant interleukin 1 receptor antagonist (IL-1Ra), (100 ng/ml), 3) dexamethasone (10E-5 M), or 4) TNF inhibitor monoclonal antibody (10 microg/ml). Supernatants were harvested at 48 hours and frozen. Immunocapture activity assays determined total MMP activity, active MMP levels and pro-MMP levels. RESULTS: Fourteen DH tissue samples were analysed. Levels of all forms of MMP-3 were higher than the respective levels of MMP-1(P < 0.01). In particular, the median (interquartile range [IQR]) total MMP-3 level was 0.97 (0.47 - 2.19) ng/mg of tissue compared to 0.024 (0.01 - 0.07) ng/mg of total MMP-1 level (P < 0.01). Incubation with IL-1Ra, dexamethasone, or TNF inhibitors significantly decreased levels of all forms of MMP-3 (P < 0.05). Dexamethasone significantly decreased the ratio of active MMP-3 to total MMP-3 activity. A significant inhibitory effect of dexamethasone was observed only on active MMP-1, while IL-1 and TNF inhibitor had no significant effect on any form. CONCLUSIONS: MMP-3 appears to play a greater role than MMP-1 in DH resorption. Dexamethasone, IL-1-Ra and TNF inhibitor decreased active MMP-3, indicating that the clinical use of these drugs may affect the resorption of DH under certain conditions

Degenerative Cervical Myelopathy and the Aging Spine: Introduction to the Special Issue.

Degenerative Cervical Myelopathy (DCM) is the most common cause of spinal cord injury in the world, but despite this, there remains many areas of uncertainty regarding the management of the condition. This special issue was dedicated to presenting current research topics in DCM. Within this issue, 12 publications are presented, including an introductory narrative overview of DCM and 11 articles comprising 9 research papers and 2 systematic reviews focusing on different aspects, ranging from genetic factors to clinical assessments, imaging, sagittal balance, surgical treatment, and outcome prediction. These articles represented contributions from a diverse group of researchers coming from multiple countries, including Switzerland, Germany, Italy, United Kingdom, United States, South Korea, and Canada

Degenerative Cervical Myelopathy: A Brief Review of Past Perspectives, Present Developments, and Future Directions.

Degenerative cervical myelopathy (DCM) is the most common cause of spinal cord injury in developed countries; its prevalence is increasing due to the ageing of the population. DCM causes neurological dysfunction and is a significant cause of disability in the elderly. It has important negative impacts on the quality of life of those affected, as well as on their caregivers. DCM is triggered by a variety of degenerative changes in the neck, which affect one or more anatomical structures, including intervertebral discs, vertebrae, and spinal canal ligaments. These changes can also lead to structural abnormalities, leading to alterations in alignment, mobility, and stability. The principle unifying problem in this disease, regardless of the types of changes present, is injury to the spinal cord due to compression by static and/or dynamic forces. This review is partitioned into three segments that focus on key elements of the past, the present, and the future in the field, which serve to introduce the focus issue on "Degenerative Cervical Myelopathy and the Aging Spine". Emerging from this review is that tremendous progress has been made in the field, particularly in recent years, and that there are exciting possibilities for further advancements of patient care

Erratum to: Dynamic transpedicular stabilisation and decompression in single-level degenerative anterolisthesis and stenosis

Background: Different treatment options exist for symptomatic single-level degenerative anterolisthesis and stenosis. While simple micro-decompression has been advocated lately, most authors recommend posterior decompression with fusion. In recent years, decompression and dynamic transpedicular stabilisation has been introduced for this indication. The aim of this study was to evaluate the safety and efficacy of decompression and dynamic transpedicular stabilisation with the Dynesys® system in single-level degenerative anterolisthesis and stenosis. Methods: Thirty consecutive patients with symptomatic single-level degenerative anterolisthesis and stenosis without scoliosis underwent decompression and single-level Dynesys stabilisation at the level of degenerative anterolisthesis. Patients were followed prospectively for 24months with radiographs, Oswestry Disability Index scores, visual analogue scale (VAS) for back and leg pain, and estimated pain-free walking distance. Results: At the 2-year follow-up, back pain was reduced from 6.5 preoperatively to 2.5, leg pain from 5.4 to 0.6. The pain-free walking distance was estimated at 500m preoperatively and at over 2km after 2years, while the ODI decreased from 54% to 18%. Screw loosening was found in 2/30 cases. Symptomatic adjacent segment disease was found in 3/30 patients between 12 and 24months postoperatively. Conclusions: Single-level Dynesys stabilisation combined with single- or multi-level decompression seems to be a safe and efficient treatment option in single-level degenerative anterolisthesis and stenosis over an observation period of 2years, avoiding iliac crest or local bone grafting required by fusion procedures. However, it does not seem to avoid adjacent segment disease