Screw Osteointegration-Increasing Biomechanical Resistance to Pull-Out Effect

Spinal disorders cover a broad spectrum of pathologies and are among the most prevalent medical conditions. The management of these health issues was noted to be increasingly based on surgical interventions. Spinal fixation devices are often employed to improve surgery outcomes, increasing spinal stability, restoring structural integrity, and ensuring functionality. However, most of the currently used fixation tools are fabricated from materials with very different mechanical properties to native bone that are prone to pull-out effects or fail over time, requiring revision procedures. Solutions to these problems presently exploited in practice include the optimal selection of screw shape and size, modification of insertion trajectory, and utilization of bone cement to reinforce fixation constructs. Nevertheless, none of these methods are without risks and limitations. An alternative option to increasing biomechanical resistance to the pull-out effect is to tackle bone regenerative capacity and focus on screw osteointegration properties. Osteointegration was reportedly enhanced through various optimization strategies, including use of novel materials, surface modification techniques (e.g., application of coatings and topological optimization), and utilization of composites that allow synergistic effects between constituents. In this context, this paper takes a comprehensive path, starting with a brief presentation of spinal fixation devices, moving further to observations on how the pull-out strength can be enhanced with existing methods, and further focusing on techniques for implant osteointegration improvement.

Epidemiological and pathological characteristics of spinal metastases from gastrointestinal cancers - a series of 40 cases

Spinal metastases from gastrointestinal (GI) cancer are rare and as a result there are only case reports or small series in the literature. The aim of our work was to identify the demographic aspects, the location, and the histopathological aspects of spinal metastases from GI cancers diagnosed and treated in a reference Hospital in Romania over a period of nine years, and comparing the data obtained with those from the recent literature. This is a retrospective case series study on spinal metastases from GI cancers, developed in patients older than 18 years that were surgically treated between January 2013 and December 2021 within three Neurosurgery Clinics from Prof. Dr. Nicolae Oblu Emergency Clinical Hospital, Iaşi, Romania, which is a tertiary Hospital in Romania regarding the surgical treatment of spinal metastases. We included in our study the patient's demographic data (age and gender), clinical data (location of spinal metastases), radiological investigations and pathological features of the lesions. Regarding the immunohistochemical stainings, the following antibodies were used: anti-cytokeratin (CK)7, anti-CK20, anti-CK19, anti-caudal-type homeobox 2 (CDX2), anti-human epidermal growth factor receptor 2 (HER2), and anti-Ki67. Our series included 40 adult patients (≥18 years old) with a male:female ratio of 3:1, in favor of male patients. The mean age of all patients was 66.42 years. The primary sites of spinal metastases from GI cancers were from all segments of the GI system: the most frequent, however, was from the colorectal level (40%) and the least from the oral cavity level (2.5%). The most common site of spinal metastases from GI cancer was predominantly lumbar region (47.5%), and the most frequent histological type was adenocarcinoma (57.5%), followed by hepatocellular carcinoma (27.5%), pancreatic ductal carcinoma (5%) and squamous cell carcinoma (2.5%). Our results have important clinical implications because they suggest that there are certain subsets of patients with certain types of GI cancers that cause metastases in certain regions of the spine.

An Overview of Oxidative Stress, Neuroinflammation, and Neurodegenerative Diseases

Oxidative stress has been linked with a variety of diseases, being involved in the debut and/or progress of several neurodegenerative disorders. This review intends to summarize some of the findings that correlate the overproduction of reactive oxygen species with the pathophysiology of Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, and amyotrophic lateral sclerosis. Oxidative stress was also noted to modify the inflammatory response. Even though oxidative stress and neuroinflammation are two totally different pathological events, they are linked and affect one another. Nonetheless, there are still several mechanisms that need to be understood regarding the onset and the progress of neurodegenerative diseases in order to develop efficient therapies. As antioxidants are a means to alter oxidative stress and slow down the symptoms of these neurodegenerative diseases, the most common antioxidants, enzymatic as well as non-enzymatic, have been mentioned in this paper as therapeutic options for the discussed disorders.

“The Silk Road” via subarachnoid cisterns

Meningiomas are generally slow-growing extra-axial benign tumours and in rare cases they can metastasize both neural and extra-neural. Intracranial meningiomas with leptomeningeal dissemination are extremely rare and the exact pathogenesis still remains unknown. The aim of this review is to analyse the pathways of intracranial and spinal metastatic spread of intracranial meningiomas and to discuss their particular clinical and pathological features. We highlight the fact that there is a possibility of leptomeningeal dissemination, even if cerebrospinal fluid cytology is negative, in patients with a medical history of a resected meningioma. We identified three possible ways of dissemination: haematogenous, through the CSF, or during surgery. From a histopathological point of view, the more malignant the meningioma, the more likely its leptomeningeal dissemination.