Craniovertebral junction (CVJ) trauma is a challenging clinical condition. Being a highly mobile functional unit at the junction of the skull and the vertebral column, traumatic events in this area may produce devastating neurological complications and death. Additionally, many of the CVJ traumatic injuries can be left undiagnosed or even raise difficult treatment dilemmas. We present a literature review in the format of recommendations on the diagnosis and management of different scenarios for upper cervical trauma and produce recommendations, which can be applicable to various areas of the globe.

Currently, there are no good clinical tools to identify the onset of secondary brain injury and/or hypoxia after traumatic brain injury (TBI). The aim of this study was to evaluate simultaneously early changes of cerebral metabolism, acid-base homeostasis, and oxygenation, as well as their interrelationship after TBI and arterial hypoxia. Cerebral biochemistry and O2 supply were measured simultaneously in a feline model of fluid-percussion injury (FPI) and secondary hypoxic injury. After FPI, brain tissue PO2 decreased from 33 +/- 5 mm Hg to 10 +/- 4 mm Hg and brain tissue PCO2 increased from 55 +/- 2 mm Hg to 81 +/- 9 mm Hg, whereas cerebral pH fell from 7.1 +/- 0.06 to 6.84 +/- 0.14 (p < 0.05 for all three measures). After 40 minutes of hypoxia, brain tissue PO2 and pH decreased further to 0 mm Hg and 6.48 +/- 0.28, respectively (p < 0.05), whereas brain tissue PCO2 remained high at 83 +/- 13 mm Hg. Secondary hypoxic injury caused a drastic increase in cerebral lactate from 513 +/- 69 microM/L to 3219 +/- 490 microM/L (p < 0.05). The lactate/glucose ratio increased from 0.7 +/- 0.1 to 9.1 +/- 2 after hypoxia was introduced. The O2 consumption decreased significantly from 18.5 +/- 1.1 microl/mg/hr to 13.2 +/- 2.1 microl/mg/hr after hypoxia was induced. Cerebral metabolism, O2 supply, and acid-base balance were severely compromised ultra-early after TBI, and they declined further if arterial hypoxia was present. The complexity of pathophysiological changes and their interactions after TBI might explain why specific therapeutic attempts that are aimed at the normalization of only one component have failed to improve outcome in severely head injured patients.

• Most spinal trauma worldwide occurs in low-and middle-income countries (LMICs). Several factors may limit the applicability of current guidelines as regards the early management of spinal injury. • The pre-hospital management per se of spinal trauma in LMICs is subject to partial adherence to recommendations, with possible impact on patient outcomes. • The use of clinical (eg ASIA) and morphological (eg SLIC, TLICS, AO Spine) grading scales is not homogeneous. • The availability and cost of diagnostic equipment, and the timing of emergency imaging can vary significantly from one region to another, probably affecting the timely management of spinal injury patients. • The introduction of resource-targeted guidelines for spinal trauma may be a valuable option to overcome the limitations of real-life application of current guidelines.

There is mounting evidence both from experimental and clinical studies that traumatic brain injury (TBI) is associated with a reduction of aerobic metabolism. This results from a variable combination of impaired substrate delivery and mitochondrial failure. Mitochondria, which are responsible for the production of 95% of cell adenosine triphosphate (ATP), may become compromised after TBI. On the other hand, in the very early period after the primary injury, oxygen delivery may be impaired due to arterial hypoxia and/or to a reduction of cerebral blood flow (CBF). As a consequence, 80-90% of patients who die of head injury show ischemia on histo-pathological examination of the brain tissue. In the absence of an appropriate treatment for TBI, these observations favored the hypothesis that manipulation of brain oxygen delivery could be a therapeutic tool to improve aerobic metabolism. Several strategies were developed, including the increase of cerebral perfusion pressure (CPP) using amines or the increase of arterial partial pressure of oxygen (PaO2) through hyperbaric oxygen (HBO) or normobaric hyperoxia. Several experimental and clinical studies, using normobaric hyperoxia, demonstrated an increase in brain tissue oxygen tension and a reduction of brain extracellular lactate levels, but there is no consensus about the biological meaning of these findings. For some authors, they translate an improvement of brain oxidative metabolism, while for others they represent only biological epiphenomena. The current review addresses the rational behind normobaric hyperoxia as a therapeutic application and discusses the experimental and clinical results achieved so far.

Study Design.: A comprehensive search was conducted in PubMed/EMBASE/MEDLINE databases. Inclusion criteria included publications between January 2011 and December 2022 on Chiari malformation (CM) diagnosis classification, natural history, and conservative management. Objective.: This study aims to offer an update on diagnosis classifications, natural history, and conservative management in CM. Background.: CM type 1 involves cerebellar tonsil herniation leading to neurological symptoms. There is controversy regarding its pathophysiology and optimal management, especially for asymptomatic cases. Previous research has focused on surgical outcomes with limited consensus on conservative strategies. Standardized guidelines are needed to enhance clinical decision-making. Materials and Methods.: The screening process involved reviewing abstracts, assessing full-text articles, and reviewing references. Eligibility criteria ensured the selection of relevant studies. Data extraction involved recording various variables. Results were discussed and voted on in 2 consensus meetings of the World Federation of Neurosurgical Societies Spine Committee, reaching a consensus using the Delphi method. Results.: A total of 164 abstracts were screened. Ninety-nine articles met the inclusion criteria and were included in the study. Headache, brainstem, and/or cerebellar/brainstem symptoms/signs were confirmed as the main typical neurological hallmarks of CM. Still, an accurate clinical assessment appeared to be the most reliable evaluation model available. Considering classification, the most common form in adults is type 1, whereas type 2 is associated with myelomeningocele and hydrocephalus from childhood. Magnetic resonance imaging is the gold standard to show the extent of tonsillar herniation, overcrowded posterior fossa, or the absence of cisterna magna. Focusing on natural history, for asymptomatic or mildly symptomatic radiologically positive patients conservative management is appropriate. Somatosensory, motor, brainstem auditory evoked potentials and polysomnography could be helpful to guide eventual surgical indication. Conclusion.: Further, higher-quality studies are recommended to establish more substantial evidence and recommendations.