Cervical spine injury response to direct rear head impact.

BACKGROUND: Direct rear head impact can occur during falls, road accidents, or sports accidents. They induce anterior shear, flexion and compression loads suspected to cause flexion-distraction injuries at the cervical spine. However, post-mortem human subject experiments mostly focus on sled impacts and not direct head impacts. METHODS: Six male cadavers were subjected to a direct rear head impact of 3.5 to 5.5 m/s with a 40 kg impactor. The subjects were equipped with accelerometers at the forehead, mouth and sternum. High-speed cameras and stereography were used to track head displacements. Head range of motion in flexion-extension was measured before and after impact for four cadavers. The injuries were assessed from CT scan images and dissection. FINDINGS: Maximum head rotation was between 43 degrees and 78 degrees, maximum cranial-caudal displacement between -12 mm and - 196 mm, and antero-posterior displacement between 90 mm and 139 mm during the impact. Four subjects had flexion-distraction injuries. Anterior vertebral osteophyte identification showed that fractures occurred at adjacent levels of osteophytic bridges. The other two subjects had no anterior osteophytes and suffered from C2 fracture, and one subject also had a C1-C2 subluxation. C6-C7 was the most frequently injured spinal level. INTERPRETATION: Anterior vertebral osteophytes appear to influence the type and position of injuries. Osteophytes would seem to provide stability in flexion for the osteoarthritic cervical spine, but to also lead to stress concentration in levels adjacent to the osteophytes. Clinical management of patients presenting with osteophytes fracture should include neck immobilization and careful follow-up to ensure bone healing.

Tensile mechanical properties of the cervical, thoracic and lumbar porcine spinal meninges.

BACKGROUND: The spinal meninges play a mechanical protective role for the spinal cord. Better knowledge of the mechanical behavior of these tissues wrapping the cord is required to accurately model the stress and strain fields of the spinal cord during physiological or traumatic motions. Then, the mechanical properties of meninges along the spinal canal are not well documented. The aim of this study was to quantify the elastic meningeal mechanical properties along the porcine spinal cord in both the longitudinal direction and in the circumferential directions for the dura-arachnoid maters complex (DAC) and solely in the longitudinal direction for the pia mater. This analysis was completed in providing a range of isotropic hyperelastic coefficients to take into account the toe region. METHODS: Six complete spines (C0 - L5) were harvested from pigs (2-3 months) weighing 43±13 kg. The mechanical tests were performed within 12 h post mortem. A preload of 0.5 N was applied to the pia mater and of 2 N to the DAC samples, followed by 30 preconditioning cycles. Specimens were then loaded to failure at the same strain rate 0.2 mm/s (approximately 0.02/s, traction velocity/length of the sample) up to 12 mm of displacement. RESULTS: The following mean values were proposed for the elastic moduli of the spinal meninges. Longitudinal DAC elastic moduli: 22.4 MPa in cervical, 38.1 MPa in thoracic and 36.6 MPa in lumbar spinal levels; circumferential DAC elastic moduli: 20.6 MPa in cervical, 21.2 MPa in thoracic and 12.2 MPa in lumbar spinal levels; and longitudinal pia mater elastic moduli: 18.4 MPa in cervical, 17.2 MPa in thoracic and 19.6 MPa in lumbar spinal levels. DISCUSSION: The variety of mechanical properties of the spinal meninges suggests that it cannot be regarded as a homogenous structure along the whole length of the spinal cord.

[Percutaneous kyphoplasty using expandable SpineJack® implant for the treatment of osteoporotic vertebral fractures]. / Traitement de la fracture vertébrale ostéoporotique par kyphoplastie percutanée avec un extenseur de type SpineJack®.

ABSTRACT: The purpose of this study was to assess the outcome of surgical management of osteoporotic vertebral fractures with percutaneous kyphoplasty using expandible SpineJack® implant. METHODS: We conducted an analytical retrospective single-center study over a period of 33-months (April 2015 - December 2017). It involved patients treated with kyphoplasty for an osteoporotic vertebral fracture. The kit consisted of a Vexim SpineJack® expandable titanium implant and acrylic cement. Patients with back pain increasing in intensity despite treatment for an osteoporotic vertebral fracture were included in the study as well as those who had undergone surgery and had given their informed consent. The vertebral fracture was diagnosed based on CT scan results and its recent state was confirmed by MRI. RESULTS: Between april 2015 and december 2017, thirty-seven patients with osteoporotic vertebral fractures were treated with kyphoplasty using expandable titanium vertebral implant. The average age of patients was 73.4 years, with a sex ratio of 0.6. Mean visual analog scale score was 7.3. Mean Oswestry score was 81.6. The patients mainly had fractures of the thoracolumbar hinge. Mean vertebral kyphotic angle was 18.45°. Kyphoplasty was used for the treatment of 44 vertebrae. Four patients had surgical complications. The average length of stay in hospital was 5.4 days. After a follow-up period of 6 months, 9 patients were still receiving analgesic therapy. After one year, no adjacent level fracture was found. CONCLUSION: Percutaneous kyphoplasty using expandible titanium implant is a safe and effective therapeutic mean for osteoporotic vertebral fractures. Given its almost immediate result, patients can rapidly get back to their active lives.

Descriptive analysis of the effect of back protector on the prevention of vertebral and thoracolumbar injuries in serious motorcycle accident.

CONTEXT AND OBJECTIVE: Among the different products and protective gear used by riders of two-wheeled motorized vehicles, back protectors that are designed to prevent damage to the spinal column are widely used today compared other protections. However, few studies measure their effectiveness. Can their effectiveness be measured? How do they help decrease or change the nature of thoracolumbar traumas that occur? To address these questions and remedy the lack of objective data regarding these products, an epidemiological, clinical, and biomechanical analysis of motorcycle riders who were admitted to a French trauma center after an accident was performed. So, this study investigates the effectiveness of back protectors, including their ability to prevent specific mechanisms of thoracic and lumbar spinal injuries related to TWMV accidents. METHOD: A questionnaire was administered to victims of accidents involving two-wheeled motorized vehicles who were admitted to the trauma room at the Marseille trauma center over the course of 2016. Collect data are related to the victim, the accident scenario, and a detailed description of the observed injuries using AIS (Abbreviated Injury Scale) coding and Magerl classification. Univariate analyses and Fisher tests were performed for victims who were or were not wearing back protectors. RESULTS: This study collected data from 124 victims. Almost half of the victims were wearing a back protector at the time of the accident (53 victims, thus 43% of riders). Collectively, twenty-nine victims who were wearing back protectors had 57 thoracolumbar injuries, and twenty eight victims who were not wearing back protectors had 75 thoracolumbar lesions. The results from this study show that there is no significant difference in the nature and mechanism of thoracolumbar injuries as a function of back protection. The majority of the thoracolumbar injuries were not severe. They were primarily bone injuries, essentially compression fractures, regardless of whether a back protector was worn. CONCLUSION: This study shows that the use of back protection does not decrease the number, type, or mechanism of thoracolumbar injuries associated with accidents involving two-wheeled motorized vehicles. However, it suggests that lumbar vertebral injuries are deflected towards the thoracic vertebrae when back protectors are worn. Finally, it suggests that the design of back protectors should be reconsidered to better protect riders from what are referred to as compression fractures (craniocaudal force), which remain the primary form of fracture regardless of the rider's characteristics, based on the data analyzed.

Two-stage free flap reconstruction of the scalp and calvaria for large neurosurgical resections.

BACKGROUND: Free tissue transfer is occasionally necessary during reconstruction of large scalp and calvarial bone resections. A single-stage procedure is usually performed but if a flap becomes necrotic it exposes brain tissue or the meninges. Performing a two-stage procedure, the surgeon must preserve flap vitality and manage flap complications before resecting a tumor, and therefore before exposing the brain or meninges. We report here the first series of two-stage free-flap reconstruction during major neurosurgical resection. METHODS: From 2012 to 2018, nine free-flaps were performed to eight patients (61 years-old, on average). Average skull resection was 10.1 cm × 15 cm (range 6-18 cm × 9-24 cm). It was performed in all cases due to large malignant tumors. Resection/reconstruction was performed in all case in a two-step procedure: during the first step, the free-flap was harvested and anastomosed to the cranial site; during the second step, resection was performed and the flap was positioned into the defect to assure coverage. RESULTS: Average flap size was 11.3 cm × 17.7 cm (range: 7-20 cm × 11-30 cm). Two flap complications occurred after the first stage and one flap did not survive. One patient died before the second stage. Seven patients had the second procedure; no flap complication occurred. All procedures ended in complete wound healing. Follow-up period was 41.5 months on average (range: 10-83 months). Final outcome was total remission for two patients, recurrence for four patients, and two patients died. CONCLUSIONS: Our data suggest that the two-stage free-flap reconstruction may be employed for major scalp and calvaria resection.

Association between vasoactive peptide urotensin II in plasma and cerebral vasospasm after aneurysmal subarachnoid hemorrhage: a potential therapeutic target.

OBJECTIVECerebral vasospasm (VS) is a severe complication of aneurysmal subarachnoid hemorrhage (SAH). Urotensin II (UII) is a potent vasoactive peptide activating the urotensin (UT) receptor, potentially involved in brain vascular pathologies. The authors hypothesized that UII/UT system antagonism with the UT receptor antagonist/biased ligand urantide may be associated with post-SAH VS. The objectives of this study were 2-fold: 1) to leverage an experimental mouse model of SAH with VS in order to study the effect of urotensinergic system antagonism on neurological outcome, and 2) to investigate the association between plasma UII level and symptomatic VS after SAH in human patients.METHODSA mouse model of SAH was used to study the impacts of UII and the UT receptor antagonist/biased ligand urantide on VS and neurological outcome. Then a clinical study was conducted in the setting of a neurosurgical intensive care unit. Plasma UII levels were measured in SAH patients daily for 9 days, starting on the 1st day of hospitalization, and were compared with plasma UII levels in healthy volunteers.RESULTSIn the mouse model, urantide prevented VS as well as SAH-related fine motor coordination impairment. Seventeen patients with SAH and external ventricular drainage were included in the clinical study. The median plasma UII level was 43 pg/ml (IQR 14-80 pg/ml). There was no significant variation in the daily median plasma UII level (median value for the 17 patients) from day 0 to day 8. The median level of plasma UII during the 9 first days post-SAH was higher in patients with symptomatic VS than in patients without VS (77 pg/ml [IQR 33.5-111.5 pg/ml] vs 37 pg/ml [IQR 21-46 pg/ml], p < 0.05). Concerning daily measures of plasma UII levels in VS, non-VS patients, and healthy volunteers, we found a significant difference between SAH patients with VS (median 66 pg/ml [IQR 30-110 pg/ml]) and SAH patients without VS (27 pg/ml [IQR 15-46 pg/ml], p < 0.001) but no significant difference between VS patients and healthy volunteers (44 pg/ml [IQR 27-51 pg/ml]) or between non-VS patients and healthy volunteers.CONCLUSIONSThe results of this study suggest that UT receptor antagonism with urantide prevents VS and improves neurological outcome after SAH in mice and that an increase in plasma UII is associated with cerebral VS subsequent to SAH in humans. The causality link between circulating UII and VS after SAH remains to be established, but according to our data the UT receptor is a potential therapeutic target in SAH.

[The management of bone metastasis]. / Prise en charge des métastases osseuses.

Bone metastasis are the most common cause of pain related to cancer, reducing patients' quality of life, and sometimes threatening their life-expectancy. Their management has to be pluridisciplinary, because of all the therapeutic options and the diversity of bone metastasis locations. The aim of this work is to propose a rational decisional algorithm for the treatment strategy of these secondary locations. Anti-resorbtive drugs with systemic action, surgery, conventional or stereotactic radiation therapy, and new techniques of interventional radiology are options that could be used separately or combined. They have shown benefits on symptomatic treatment, improving quality of life. Their indications vary according to the tumor site (short vs. long bones, carrier vs. non-carrier bones), the symptomatology (pain, neurologic symptoms), and the presence of complications (most of all fractures). The diverse presentations lead us to define this decisional algorithm, to guide the practice, while giving the maximal benefit to each patient according to each metastasis.

Analysis of Injury Mechanisms in Head Injuries in Skiers and Snowboarders.

PURPOSE: Mechanisms of injury and description of head impacts leading to traumatic brain injury (TBI) in skiers and snowboarders have not been extensively documented. We investigate snow sport crashes leading to TBI 1) to identify typical mechanisms leading to TBI to better target prevention measures and 2) to identify the injury mechanisms and the head impact conditions. METHODS: The subjects were skiers and snowboarders diagnosed of TBI and admitted between 2013 and 2015 to one of the 15 medical offices and three hospital centers involved in the study. The survey includes the description of the patients (age, sex, practice, skill level, and helmet use), the crash (type, location, estimated speed, causes, and fall description), and the injuries sustained (symptoms, head trauma scores, and other injuries). Sketches were used to describe the crash and impact locations. Clustering methods were used to distinguish profiles of injured participants. RESULTS: A total of 295 skiers and 71 snowboarders were interviewed. The most frequent type of mechanism was falls (54%), followed by collision between users (18%) and jumps (15%). Collision with obstacle (13%) caused the most serious TBI. Three categories of patients were identified. First, men age 16-25 yr are more involved in crash at high speed or in connection with a jump. Second, women, children (<16 yr), and beginners are particularly injured in collisions between users. Third, those older than 50 yr, usually nonhelmeted, are frequently involved in falls. Ten crash scenarios were identified. Falling head first is the most frequent of skiers' falls (28%). CONCLUSION: Crash scenarios leading to TBI were identified and associated with profiles of injured participants. Those results should help to better target TBI prevention and protection campaigns.

Aneurisma intracraneal traumático secundario a un trauma balístico. Caso clínico y revisión de la literatura / Traumatic intracranial aneurysm secondary to a bullet wound. Clinical case and a review of the literature

Los aneurismas intracraneales traumáticos (AICT) son raros y están asociados con altas tasas de morbimortalidad. Los AICT son el resultado de lesiones en la cabeza causadas por accidentes, explosiones y disparos. Describimos el caso de un hombre de 28años que fue admitido en nuestro hospital después de sufrir una lesión craneal penetrante causada por una bala. Los estudios radiográficos demostraron una hemorragia subaracnoidea interhemisférica y una imagen probable de AICT que pasó inicialmente desapercibida. Una semana después se le realiza una arteriografía cerebral, la cual demuestra un vasoespasmo bilateral de la porción terminal de la arteria carótida interna (ACI) y la aparición de un AICT fusiforme de la rama orbitofrontal de la arteria cerebral anterior (ACA) de 2mm que fue tratado de manera quirúrgica tras un crecimiento del aneurisma de 3,4mm y un fallo del tratamiento endovascular. El paciente tuvo una evolución favorable en el postoperatorio

Traumatic intracranial aneurysms (AICT) are rare and are associated with high morbidity and mortality. AICT are the result of head injuries caused by accidents, explosions, and gunfire. The case is reported here of a 28 year old man who was admitted to our hospital after suffering a penetrating head injury caused by a bullet. Radiographic studies showed interhemispheric subarachnoid haemorrhage and a likely AICT image that initially went unnoticed. One week later he underwent a cerebral angiography which showed a bilateral vasospasm of the terminal portion of the internal carotid and the appearance of a 2mm fusiform AICT at the orbit-frontal branch of the anterior cerebral artery. This was surgically treated after an aneurismal growth of 3.4mm and failure of the endovascular treatment. The patient showed a favourable outcome after surgery

Arteriovenous malformation of the filum terminale: an exceptional case.

Arteriovenous malformations (AVMs) of the spine display a variety of different locations, angioarchitectures, and clinical presentations. The authors describe an exceptional case of a filum terminale AVM that is not described in any classification and discuss the origin and management of this malformation. A 59-year-old woman was admitted in June 2012 for cauda equina syndrome. Magnetic resonance imaging and spinal angiography revealed an AVM of the filum terminale, located below the conus medullaris, fed by the anterior spinal artery. After an unsuccessful attempt to reach the nidus with a microcatheter, the AVM was resected. At 20 months after surgery, the patient was fully independent and radiological images confirmed the exclusion of the malformation. AVMs that originate from the filum terminale are exceptional. According to updated classifications, AVMs of the filum terminale should be categorized as a separate entity.

[Traumatic intracranial aneurysm secondary to a bullet wound. Clinical case and a review of the literature]. / Aneurisma intracraneal traumático secundario a un trauma balístico. Caso clínico y revisión de la literatura.

Traumatic intracranial aneurysms (AICT) are rare and are associated with high morbidity and mortality. AICT are the result of head injuries caused by accidents, explosions, and gunfire. The case is reported here of a 28 year old man who was admitted to our hospital after suffering a penetrating head injury caused by a bullet. Radiographic studies showed interhemispheric subarachnoid haemorrhage and a likely AICT image that initially went unnoticed. One week later he underwent a cerebral angiography which showed a bilateral vasospasm of the terminal portion of the internal carotid and the appearance of a 2mm fusiform AICT at the orbit-frontal branch of the anterior cerebral artery. This was surgically treated after an aneurismal growth of 3.4mm and failure of the endovascular treatment. The patient showed a favourable outcome after surgery.

Risk factors for surgical site infections after neurosurgery: A focus on the postoperative period.

BACKGROUND: Surgical site infection (SSI) after neurosurgery has potentially devastating consequences. METHODS: A prospective cohort study was conducted over a period of 24 months in a university center. All adult patients undergoing neurosurgical procedures, with exception of open skull fractures, were included. Multivariate logistic regression analysis was used to identify independent risk factors. RESULTS: We included 949 patients. Among them, 43 were diagnosed with SSI (4.5%). A significant reduction in postneurosurgical SSI from 5.8% in 2009 to 3.0% in 2010 (P = .04) was observed. During that period, an active surveillance with regular feedback was established. The most common microorganisms isolated from SSI were Staphylococcus aureus (23%), Enterobacteriaceae (21%), and Propionibacterium acnes (12%). We identified the following independent risk factors for SSI postcranial surgery: intensive care unit (ICU) length of stay ≥7 days (odds ratio [OR] = 6.1; 95% confidence interval [CI], 1.7-21.7), duration of drainage ≥3 days (OR = 3.3; 95% CI, 1.1-11), and cerebrospinal fluid leakage (OR = 5.6; 95% CI, 1.1-30). For SSIs postspinal surgery, we identified the following: ICU length of stay ≥7 days (OR = 7.2; 95% CI, 1.6-32.1), coinfection (OR = 9.9; 95% CI, 2.2-43.4), and duration of drainage ≥3 days (OR = 5.7; 95% CI, 1.5-22). CONCLUSION: Active surveillance with regular feedback proved effective in reducing SSI rates. The postoperative period is associated with overlooked risk factors for neurosurgical SSI. Infection control measures targeting this period are therefore promising.

Is there any benefit from short-term perioperative antiepileptic prophylaxis in patients with chronic subdural haematoma? A retrospective controlled study.

BACKGROUND: Chronic subdural haematoma is a common pathology, which can be complicated by seizures. Seizures may worsen the outcome of patients presenting with a chronic subdural haematoma. However, since the overall and postoperative incidence of seizures and their impact on patients' outcome has been diversely appreciated in the literature, the interest of routine antiepileptic prophylaxis remains a controversial question. METHODS: We retrospectively investigated 99 patients who were surgically treated for a chronic subdural haematoma in two French academic hospitals: 48 patients received antiepileptic prophylaxis (group A) and were compared with a group of 51 patients who did not receive any antiepileptic prophylaxis (group B). Incidence of perioperative seizures was determined, and potential risk factors for epilepsy were analysed. RESULTS: Overall postoperative seizure incidence was 5.1%. There was a slight trend towards a lower incidence of seizures in patients who had received antiepileptic prophylaxis, but no significant difference was found between the two groups (4.2% in group A versus 5.9% in group B, P=0.697). Seizures were not correlated with increased death. No risk factor for seizures was identified. CONCLUSIONS: Our retrospective data showed there is no benefit of perioperative antiepileptic prophylaxis in patients surgically treated for chronic subdural haematoma. Since other authors have shown conflicting results, sufficiently powered prospective randomized study should be conducted in order to confirm these results.

Decision making for the surgical approach of posterior petrous bone meningiomas.

OBJECT: The authors undertook this study to examine the surgical approaches used to treat posterior petrous bone meningiomas at a single institution and retrospectively evaluate their surgical strategy based on a previously published classification. METHODS: Cases in which craniotomies were performed to treat posterior petrous bone meningiomas between 2002 and 2010 were retrospectively reviewed. Data were examined from 57 patients who were treated for 59 tumors. The tumors were classified into 3 types according to the location of their primary dural attachment: Type A, located around the porus trigeminus (33 tumors); Type M, located at the level of the porus of the internal auditory canal (IAC) (12 tumors); and Type P, located laterally to the IAC (14 tumors). The median tumor diameter was 34 mm (range 20-67 mm). RESULTS: The choice of the approach was based on tumor location, as the displacement of vascular structures and cranial nerves was primarily determined by the site of dural attachment on the posterior petrous bone. An anterior petrosectomy was performed in 82% of Type A meningiomas, and a retrosigmoid approach was used in 86% of Type P meningiomas. The spectrum of approaches was less uniform for Type M meningiomas. Overall, total resection was obtained in 39% of all cases, and in 18%, 50%, and 86% of Type A, Type M, and Type P tumors, respectively. The postoperative mortality rate was 8.8% (5 deaths among 57 patients), and all 5 patients who died during the early postoperative period had large Type A tumors. At last follow-up, the functional preservation of the facial nerve was excellent in 49 (94%) of the 52 surviving patients. CONCLUSIONS: The authors believe that proper selection of the approach favorably impacts functional outcome in patients undergoing surgery for the treatment of skull base tumors. In the authors' case series of posterior petrous bone meningiomas, Type P and most Type M tumors were safely managed through a regular retrosigmoid approach, whereas Type A tumors were optimally treated via an epidural anterior petrosectomy.