Safety and efficacy of transvenous embolization of cerebrospinal fluid-venous fistula in patients with spontaneous intracranial hypotension

BACKGROUND

Transvenous embolization is a recent treatment strategy for cerebrospinal fluid-venous fistulas (CSFVF), which are associated with spontaneous intracranial hypotension (SIH).

METHODS

Participants were selected from a prospective database on patients with CSFVF that received transvenous Onyx embolization. All patients underwent a brain magnetic resonance imaging (MRI) before and after embolization with MRI follow-up performed at least 3 months after treatment. Clinical and MRI results after treatment were described.

RESULTS

Twenty-one consecutive patients (median age 63 years, IQR = 58-71; females: 15/21 = 71.5%) with 30 CSFVF were included. Most lesions were situated between T9 and L1 (19/30 = 63%), 70% were right-sided, and 38% of the patients had multiples fistulas. Embolization was successful in all cases. The mean MRI SIH score before and after treatment was 6 (±2.5) and 1.4 (±1.6), respectively (p < 0.0001). Twenty patients (90%) experienced improvement of their initial condition, of which 67% reported complete clinical recovery. The mean HIT-6 score decreased from 67 (±15) to 38 (±9) (p < 0.0001), the mean amount of monthly headache days from 23.5 (±10) and 3.2 (±6.6) (p < 0.0001), the visual assessment scale (VAS) for headache severity from 8 (±1.9) to 1.2 (±2) (p < 0.0001), and the mean VAS for perception quality of life improved from 2.6 (±2.5) to 8.6 (±1.8) (p < 0.0001). There were no major complications. The suspected rebound headache rate after treatment was 33%.

CONCLUSION

Transvenous embolization of CSFVF allowed high rates of clinical improvement with no morbidity related to the treatment.

Induction of antiviral interferon-stimulated genes by neuronal STING promotes the resolution of pain in mice

Inflammation and pain are intertwined responses to injury, infection, or chronic diseases. While acute inflammation is essential in determining pain resolution and opioid analgesia, maladaptive processes occurring during resolution can lead to the transition to chronic pain. Here we found that inflammation activates the cytosolic DNA-sensing protein stimulator of IFN genes (STING) in dorsal root ganglion nociceptors. Neuronal activation of STING promotes signaling through TANK-binding kinase 1 (TBK1) and triggers an IFN-β response that mediates pain resolution. Notably, we found that mice expressing a nociceptor-specific gain-of-function mutation in STING exhibited an IFN gene signature that reduced nociceptor excitability and inflammatory hyperalgesia through a KChIP1-Kv4.3 regulation. Our findings reveal a role of IFN-regulated genes and KChIP1 downstream of STING in the resolution of inflammatory pain.

Spinal lymphangiomas: Case-based review of a chameleonic disease entity

Purpose

Lymphangiomas are benign hamartomas in the spectrum of lymphatic malformations, exhibiting multifaceted clinical features. Spinal involvement is exceedingly rare, with only 35 cases reported to date. Both due to their rarity and chameleonic radiologic features, spinal lymphangiomas (SLs) are usually misdiagnosed; postoperatively, surgeons are thus confronted with an unexpected histopathological diagnosis with sparse pertinent literature and no treatment guidelines available.

Methods

Here, we report the case of a 67-year-old female who underwent surgery for a T6-T7 epidural SL with transforaminal extension, manifesting with spastic paraparesis. Then, we present the results of the first systematic review of the literature on this subject, delineating the clinical and imaging features and the therapeutic implications of this rare disease entity.

Results

Our patient was treated with T6-T7 hemilaminectomy and resection of the epidural mass, with complete recovery of her neurological picture. No recurrence was evident at 18 months. In the literature, 35 cases of SL were reported that can be classified as vertebral SL (n = 18), epidural SL (n = 10), intradural SL (n = 3), or intrathoracic lymphangiomas with secondary spinal involvement (n = 4). Specific treatment strategies (both surgical and nonsurgical) were adopted in relation to each of these categories.

Conclusion

Gathering knowledge about SL is fundamental to promote both correct preoperative identification and appropriate perioperative management of this rare disease entity. By reviewing the literature and discussing an exemplary case, we delineate a framework that can guide surgeons facing such an unfamiliar diagnosis.

A technique to localize posteriorly located spinal dural leaks associated with spontaneous intracranial hypotension: Dorsal-decubitus dynamic CT myelography

BACKGROUND

Precise localization and understanding of the origin of cerebrospinal fluid (CSF) leak is crucial to allow targeted treatment. We report the technical feasibility and utility of dorsal-decubitus dynamic computed tomography (DDDCT) myelography to localize posteriorly located dural defects in patients with suspicion of posterolateral dural tears.

METHODS

This study reports a series of four consecutive patients with posteriorly located SLEC and suspicion of posterolateral CSF leak who received DDDCT to localize the site of the leak. Patients were collected between October 2022 and October 2023. The technique of DDDCT and its efficacy to detect the site of CSF leak are reported.

RESULTS

In all four patients (three females, one male, mean age 39 years), DDDCT myelography was technically successful and precisely demonstrated the site of the CSF leak. In one patient with both anterior and posterior SLEC, DDDCT allowed to exclude the presence of a posteriorly located leak, while a subsequent ventral decubitus dynamic CT myelography localized the leak. Leak sites were all thoracic, except for one that was cervical. Information obtained from the DDDCT myelography was considered useful to target the treatment of the leak.

CONCLUSIONS

Based on our experience, DDDCT provided sufficient spatial and temporal resolution to pinpoint fast CSF leaks and it may be considered to localize posterolateral dural defects.

Becoming a neurosurgeon in France: A qualitative study from the trainees' perspective

Introduction

The training of neurosurgeons is evolving in a world of socio-professional changes, including the technological revolution, administrative pressure on stakeholders, reduced working hours, geographical heterogeneity, generational changes, to name but a few.

Research question

This qualitative study aimed to explore experiences and feedback of French neurosurgical trainees concerning their training.

Material and methods

The grounded theory approach was used with 23 neurosurgical trainees' interviews. Inclusion was continued until data saturation. Six researchers (an anthropologist, a psychiatrist, and four neurosurgeons) thematically and independently analyzed data collected through anonymized interviews.

Results

Data analysis identified three superordinate themes: (1) The Trainee-Senior Dyad, where the respondents describe a similar bipolarity between trainees and faculty (trainees oscillating between those who fit into the system and those who are more reluctant to accept hierarchy, faculty using an ideal pedagogy while others refuse to help or invest in training); (2) The difficulty to learn (describing pressure exercised on trainees that can alter their motivation and degrade their training, including the impact of administrative tasks); (3) A pedagogy of empowerment (trainee' feelings about the pertinent pedagogy in the OR, ideal sequence to progress, progressive empowerment especially during the shifts, and stress of envisioning themselves as a senior neurosurgeon).

Discussion and conclusion

Respondents emphasize the heterogeneity of their training both intra- and inter-university-hospital. Their critical analysis, as well as the formalization of their stress to become autonomous seniors, can be an important link with the reforms and optimizations currently being carried out to improve and standardize the training of young French neurosurgeons.

Persistence of FoxJ1+ Pax6+ Sox2+ ependymal cells throughout life in the human spinal cord

Ependymal cells lining the central canal of the spinal cord play a crucial role in providing a physical barrier and in the circulation of cerebrospinal fluid. These cells express the FOXJ1 and SOX2 transcription factors in mice and are derived from various neural tube populations, including embryonic roof and floor plate cells. They exhibit a dorsal-ventral expression pattern of spinal cord developmental transcription factors (such as MSX1, PAX6, ARX, and FOXA2), resembling an embryonic-like organization. Although this ependymal region is present in young humans, it appears to be lost with age. To re-examine this issue, we collected 17 fresh spinal cords from organ donors aged 37-83 years and performed immunohistochemistry on lightly fixed tissues. We observed cells expressing FOXJ1 in the central region in all cases, which co-expressed SOX2 and PAX6 as well as RFX2 and ARL13B, two proteins involved in ciliogenesis and cilia-mediated sonic hedgehog signaling, respectively. Half of the cases exhibited a lumen and some presented portions of the spinal cord with closed and open central canals. Co-staining of FOXJ1 with other neurodevelopmental transcription factors (ARX, FOXA2, MSX1) and NESTIN revealed heterogeneity of the ependymal cells. Interestingly, three donors aged > 75 years exhibited a fetal-like regionalization of neurodevelopmental transcription factors, with dorsal and ventral ependymal cells expressing MSX1, ARX, and FOXA2. These results provide new evidence for the persistence of ependymal cells expressing neurodevelopmental genes throughout human life and highlight the importance of further investigation of these cells.

A cellular taxonomy of the adult human spinal cord

The mammalian spinal cord functions as a community of cell types for sensory processing, autonomic control, and movement. While animal models have advanced our understanding of spinal cellular diversity, characterizing human biology directly is important to uncover specialized features of basic function and human pathology. Here, we present a cellular taxonomy of the adult human spinal cord using single-nucleus RNA sequencing with spatial transcriptomics and antibody validation. We identified 29 glial clusters and 35 neuronal clusters, organized principally by anatomical location. To demonstrate the relevance of this resource to human disease, we analyzed spinal motoneurons, which degenerate in amyotrophic lateral sclerosis (ALS) and other diseases. We found that compared with other spinal neurons, human motoneurons are defined by genes related to cell size, cytoskeletal structure, and ALS, suggesting a specialized molecular repertoire underlying their selective vulnerability. We include a web resource to facilitate further investigations into human spinal cord biology.

Endoscopic transsphenoidal surgery for non-functioning pituitary adenoma: Learning curve and surgical results in a prospective series during initial experience

Background

To report the initial experience of surgery for non-functioning pituitary adenoma (NFPA) from a neurosurgeon in a dedicated residency training endoscopic transsphenoidal (ETS) program, and detail the surgical and clinical outcomes during this period.

Methods

A prospective series of all patients operated for NFPA, using an ETS approach, during the three first years of experience of a newly board-certified neurosurgeon was analysed. Clinical, radiological and peri-operative data were collected. Extent of resection (EOR) was determined by formal volumetric analysis. Impact of the learning curve and predictive factors of gross total resection (GTR) were determined.

Results

Fifty-three patients with NFPA were included in this prospective cohort which was divided in two periods of time (“First period”: 30 first cases, and “second period”: 23 following cases). Baseline characteristics of the patients in the two periods were similar. Overall occurrence of complication was 22% and was not significantly different in the two periods of time. No patient had severe neurological complication. Gross total resection was achieved in 70% of patients. Mean Extent of resection was 96%. In a multiple linear regression model, a higher EOR was positively correlated with experience (p = 0.018) and negatively correlated with Knosp Score equal to 4 (p < 0.001). Predictive factors for GTR were Higher Knosp grade (p = 0,01), higher pre-operative volume (p = 0.03), and second period of time (p = 0.01).

Conclusion

NFPA surgery can be safe and efficient during the learning period. Dedicated intensive learning, careful patient selection and multidisciplinary work are key to shorten the learning curve and achieve satisfactory results.

The neuronal tyrosine kinase receptor ligand ALKAL2 mediates persistent pain

The anaplastic lymphoma kinase (ALK) is a receptor tyrosine kinase known for its oncogenic potential that is involved in the development of the peripheral and central nervous system. ALK receptor ligands ALKAL1 and ALKAL2 were recently found to promote neuronal differentiation and survival. Here, we show that inflammation or injury enhanced ALKAL2 expression in a subset of TRPV1⁺ sensory neurons. Notably, ALKAL2 was particularly enriched in both mouse and human peptidergic nociceptors, yet weakly expressed in nonpeptidergic, large-diameter myelinated neurons or in the brain. Using a coculture expression system, we found that nociceptors exposed to ALKAL2 exhibited heightened excitability and neurite outgrowth. Intraplantar CFA or intrathecal infusion of recombinant ALKAL2 led to ALK phosphorylation in the lumbar dorsal horn of the spinal cord. Finally, depletion of ALKAL2 in dorsal root ganglia or blocking ALK with clinically available compounds crizotinib or lorlatinib reversed thermal hyperalgesia and mechanical allodynia induced by inflammation or nerve injury, respectively. Overall, our work uncovers the ALKAL2/ALK signaling axis as a central regulator of nociceptor-induced sensitization. We propose that clinically approved ALK inhibitors used for non–small cell lung cancer and neuroblastomas could be repurposed to treat persistent pain conditions.

Combined video-assisted thoracoscopy surgery and posterior midline incision for en bloc resection of non-small-cell lung cancer invading the spine

OBJECTIVES

This article aims to evaluate the feasibility and safety of a hybrid video-assisted thoracic surgery (VATS) approach to achieve en bloc lobectomy and spinal resection for non-small-cell lung cancer (NSCLC).

METHODS

Between October 2015 and November 2020, 10 patients underwent VATS anatomical lobectomy and en bloc chest wall and spinal resection through a limited posterior midline incision as a single operation for T4 (vertebral involvement) lung cancer. Nine patients had Pancoast syndrome without vascular involvement and 1 patient had NSCLC of the right lower lobe with invasion of T9 and T10.

RESULTS

There were 5 men and 5 women. The mean age was 61 years (range: 47-74 years). Induction treatment was administered to 9 patients (90%). The average operative time was 315.5 min (range: 250-375 min). The average blood loss was 665 ml (range: 100-2500 ml). Spinal resection was hemivertebrectomy in 6 patients and wedge corpectomy in 4 patients. Complete resection (R0) was achieved in all patients. The average hospitalization stay was 14 days (range: 6-50 days). There was no in-hospital mortality. The mean follow-up was 32.3 months (range: 6-66 months). Six patients (60%) are alive without recurrence.

CONCLUSIONS

VATS is feasible and safe to achieve en bloc resection of NSCLC inviding the spine without compromising oncological efficacy. Further experience and longer follow-up are needed to determine if this approach provides any advantages over thoracotomy.

Spine Surgery Infection, Litigation, and Financial Compensation: Analysis of 98 Claims Involving French Spine Surgeons Between 2015 and 2019

OBJECTIVE

Since 2002, France has adopted the Patients' Rights Law, an alternative malpractice scheme creating a faster, less expensive out-of-court settlement ensuring compensation even in the absence of fault. We aimed to describe the implications of this system by analyzing 5 years of claims for infections related to spinal surgeries collected by the main insurer of French spine surgeons.

METHODS

We retrospectively analyzed 98 anonymized malpractice claims from 2015 to 2019 (20% of overall claims), including anonymized medical records of the patients, reports of the independent experts, final judgments, and entities supporting the compensation if any.

RESULTS

Claims included 8 deaths and 17 newly acquired neurological sequelae. The conclusions identified 22 faulty cases. The most frequent fault was a delay in diagnosis (10 cases), followed by inadequate surgical management (6 cases), inadequate antibiotic therapy (5 cases), and inadequate follow-up (1 case). Among the 67 cases (68.4%) proved not to be at fault, 10 were covered by the national solidarity fund because of their severity, and the remaining 57 were covered by hospitals.

CONCLUSIONS

Since the 2002 Patients' Rights Law, patients with postoperative infections have always received compensation. The out-of-court settlement offers the patients incurring morbidities the assurance of faster compensation. Although certainly subject to selection criteria, this procedure is free and does not necessitate the presence of a lawyer. The analysis of expert reports and the resulting court decisions imply prevention, anticipation, and collaboration of all health care providers and open an opportunity to improve their practices to limit these crucial followings.

Inhibiting microglia proliferation after spinal cord injury improves recovery in mice and nonhuman primates

No curative treatment is available for any deficits induced by spinal cord injury (SCI). Following injury, microglia undergo highly diverse activation processes, including proliferation, and play a critical role on functional recovery.

In a translational objective, we investigated whether a transient pharmacological reduction of microglia proliferation after injury is beneficial for functional recovery after SCI in mice and nonhuman primates.

Methods: The colony stimulating factor-1 receptor (CSF1R) regulates proliferation, differentiation, and survival of microglia. We orally administrated GW2580, a CSF1R inhibitor that inhibits microglia proliferation. In mice and nonhuman primates, we then analyzed treatment outcomes on locomotor function and spinal cord pathology. Finally, we used cell-specific transcriptomic analysis to uncover GW2580-induced molecular changes in microglia.

Results: First, transient post-injury GW2580 administration in mice improves motor function recovery, promotes tissue preservation and/or reorganization (identified by coherent anti-stokes Raman scattering microscopy), and modulates glial reactivity.

Second, post-injury GW2580-treatment in nonhuman primates reduces microglia proliferation, improves motor function recovery, and promotes tissue protection.

Finally, GW2580-treatment in mice induced down-regulation of proliferation-associated transcripts and inflammatory associated genes in microglia that may account for reduced neuroinflammation and improved functional recovery following SCI.

Conclusion: Thus, a transient oral GW2580 treatment post-injury may provide a promising therapeutic strategy for SCI patients and may also be extended to other central nervous system disorders displaying microglia activation.

Injury characteristics, initial clinical status, and severe injuries associated with spinal fractures in a retrospective cohort of 506 trauma patients

BACKGROUND

Our aim was to describe the characteristics of vertebral fractures, the presence of associated injuries, and clinical status within the first days in a severe trauma population.

METHODS

All patients with severe trauma admitted to our level 1 trauma center between January 2015 and December 2018 with a vertebral fracture were analyzed retrospectively. The fractures were determined by the AO Spine classification as stable (A0, A1, and A2 types) or unstable (A3, A4, B, and C types). Clinical status was defined as stable, intermediate, or unstable based on clinicobiological parameters and anatomic injuries. Severe extraspinal injuries and emergent procedures were studied. Three groups were compared: stable fracture, unstable fracture, and spinal cord injury (SCI) group.

RESULTS

A total of 425 patients were included (mean ± SD age, 43.8 ± 19.6 years; median Injury Severity Score, 22 [interquartile range, 17-34]; 72% male); 72 (17%) in the SCI group, 116 (27%) in the unstable fracture group, and 237 (56%) in the stable fracture group; 62% (95% confidence interval [CI], 57-67%) had not a stable clinical status on admission (unstable, 30%; intermediate, 32%), regardless of the group (p = 0.38). This decreased to 31% (95% CI, 27-35%) on day 3 and 23% (95% CI, 19-27%) on day 5, regardless of the group (p = 0.27 and p = 0.25). Progression toward stable clinical status between D1 and D5 was 63% (95% CI, 58-68%) overall but was statistically lower in the SCI group. Severe extraspinal injuries (85% [95% CI, 82-89%]) and extraspinal emergent procedures (56% [95% CI, 52-61%]) were comparable between the three groups. Only abdominal injuries and hemostatic procedures significantly differed significantly (p = 0.003 and p = 0.009).

CONCLUSION

More than the half of the patients with severe trauma had altered initial clinical status or severe extraspinal injuries that were not compatible with safe early surgical management for the vertebral fracture. These observations were independent of the stability of the fracture or the presence of an SCI.

LEVEL OF EVIDENCE

Prognostic and epidemiological, level III.

Corticosteroids as an Adjuvant Treatment to Surgery in Chronic Subdural Hematomas: A Multi-Center Double-Blind Randomized Placebo-Controlled Trial

Chronic subdural hematoma (CSDH) is a common condition necessitating surgery; however, recurrence occurs in 15-25% of cases despite surgical management. The HEMACORT trial was a prospective randomized, double-blind, placebo-controlled, multi-centric study (NCT01380028). The aim of this trial was to determine the effect of corticosteroids as an adjuvant treatment to surgery on CSDH recurrence at 6 months. After surgery, participants were assigned by block-randomization to receive either placebo or oral prednisone at a dose of 1 mg/kg/day followed by weekly stepwise tapering in steps of 10 mg/day. The primary outcome was CSDH recurrence, defined by the need for reoperation and/or radiological progression of CSDH. Secondary outcomes were one-year death, radiological changes, safety, neurological status, and quality of life. The trial was discontinued at midpoint of expected inclusions: 78 participants received prednisone and 77 received placebo controls. In an intention-to-treat analysis, CSDH clinicoradiological recurrence was not different between prednisone and placebo groups (21.8% vs. 35.1%, respectively; hazard ratio 0.56; 95% confidence interval 0.30-1.02; p = 0.06), although post hoc analyses concluded to statistical significance (p = 0.02). Earlier radiological resolution was observed after prednisone administration, but reoperation rates (reaching 5.8% overall) and functional outcomes were not different at 6 months. Among adverse events, sleep disorders occurred more often in the prednisone group (26.1% vs. 9.1%, p = 0.02). The HEMACORT trial data suggest that prednisone, as an adjuvant treatment to surgery, may reduce early radiological recurrence of CSDH, although clinical benefits are unclear. In view of these findings, the authors suggest that shorter treatment duration should be assessed for safety and efficacy in future trials.

Security and reliability of CUSTOMBONE cranioplasties: A prospective multicentric study

BACKGROUND

Repairing bone defects generated by craniectomy is a major therapeutic challenge in terms of bone consolidation as well as functional and cognitive recovery. Furthermore, these surgical procedures are often grafted with complications such as infections, breaches, displacements and rejections leading to failure and thus explantation of the prosthesis.

OBJECTIVE

To evaluate cumulative explantation and infection rates following the implantation of a tailored cranioplasty CUSTOMBONE prosthesis made of porous hydroxyapatite. One hundred and ten consecutive patients requiring cranial reconstruction for a bone defect were prospectively included in a multicenter study constituted of 21 centres between December 2012 and July 2014. Follow-up lasted 2 years.

RESULTS

Mean age of patients included in the study was 42±15 years old (y.o), composed mainly by men (57.27%). Explantations of the CUSTOMBONE prosthesis were performed in 13/110 (11.8%) patients, significantly due to infections: 9/13 (69.2%) (p<0.0001), with 2 (15.4%) implant fracture, 1 (7.7%) skin defect and 1 (7.7%) following the mobilization of the implant. Cumulative explantation rates were successively 4.6% (SD 2.0), 7.4% (SD 2.5), 9.4% (SD 2.8) and 11.8% (SD 2.9%) at 2, 6, 12 and 24 months. Infections were identified in 16/110 (14.5%): 8/16 (50%) superficial and 8/16 (50%) deep. None of the following elements, whether demographic characteristics, indications, size, location of the implant, redo surgery, co-morbidities or medical history, were statistically identified as risk factors for prosthesis explantation or infection.

CONCLUSION

Our study provides relevant clinical evidence on the performance and safety of CUSTOMBONE prosthesis in cranial procedures. Complications that are difficulty incompressible mainly occur during the first 6 months, but can appear at a later stage (>1 year). Thus assiduous, regular and long-term surveillances are necessary.

Cerebral venous sinus thrombosis following post-neurosurgical intracranial hypotension: A case report and systematic review of the literature

Cerebral venous sinus thrombosis (CVST) following brain surgery is a feared complication, commonly described after direct injury to the sinus. However, distant CVST occurring away from the operative area are unexpected. Yet, there is a strong physio-pathological rational supporting the role of intracranial hypotension as a risk factor of CVST. Here, we report the case of a frontal arachnoid cyst depletion followed by an extensive contralateral CVST. Given the major prognostic consequences observed in this clinical illustration, we further investigated the hypothesis of intracranial hypotension as an etiology of CVST by carrying out a systematic review of the literature.

C1-C2 Injury: Factors influencing mortality, outcome, and fracture healing

BACKGROUND

C1-C2 injury represents 25-40% of cervical injuries and predominantly occurs in the geriatric population.

METHODS

A prospective multicentre study was conducted under the aegis of the french spine surgery society (SFCR) investigating the impact of age, comorbidities, lesion type, and treatment option on mortality, complications, and fusion rates.

RESULTS

A total of 417 patients were recruited from 11 participating centres. The mean ± SD age was 66.6 ± 22 years, and there were 228 men (55%); 5.4% presented a neurological deficit at initial presentation. The most frequent traumatic lesion was C2 fracture (n = 308). Overall mortality was 8.4%; it was 2.3% among those aged ≤ 60 years, 5.0% 61-80 years, and 16.0% > 80 years (p < 0.001). Regarding complications, 17.8% of patients ≤ 70 years of age presented with ≥ 1 complication versus 32.3% > 70 years (p = 0.0009). The type of fracture did not condition the onset of complications and/or mortality (p > 0.05). The presence of a comorbidity was associated with a risk factor for both death (p = 0.0001) and general complication (p = 0.008). Age and comorbidities were found to be independently associated with death (p < 0.005). The frequency of pseudoarthrosis ranged from 0 to 12.5% up to 70 years of age and then constantly and progressively increased to reach 58.6% after 90 years of age.

CONCLUSIONS

C1-C2 injury represents a serious concern, possibly life-threatening, especially in the elderly. We found a major impact of age and comorbidities on mortality, complications, and pseudarthrosis; injury pattern or treatment option seem to have a minimal effect.

Litigations following spinal neurosurgery in France: “out-of-court system,” therapeutic hazard, and welfare state

OBJECTIVE

Spinal surgeries carry risks of malpractice litigation due to the random nature of their functional results, which may not meet patient expectations, and the hazards associated with these complex procedures. Claims are frequent and costly. In France, since 2002, a new law, the Patients’ Rights Law of March 4, 2002, has created an alternative, out-of-court scheme, which established a simplified, rapid, free-of-charge procedure (Commission for Conciliation and Compensation [CCI]). Moreover, this law has optimized the compensation provided to patients for therapeutic hazards by use of a national solidarity fund. The authors analyzed the consequences of this alternative route in the case of claims against private neurosurgeons in France.

METHODS

From the data bank of the insurer Mutuelle d’Assurances du Corps de Santé Français (MACSF), the main insurance company for private neurosurgeons in France, the authors retrospectively analyzed 193 files covering the period 2015–2019. These computerized files comprised the anonymized medical records of the patients, the reports of the independent experts, and the final judgments of the CCI and the entities supporting the compensation, if any.

RESULTS

During the 5-year study period (2015–2019), the insurance company recorded 494 complaints involving private neurosurgeons for spinal surgery procedures, of which 126 (25.5%) were in civil court, 123 (24.9%) were under amicable procedure, and 245 (49.6%) were in the out-of-court scheme administered by the CCI. Out of these 245 cases, only 193 were closed due to delays. The conclusions of the commission were rejection/incompetence decisions in 47.2% of the cases, therapeutic hazards in 21.2%, nosocomial infections in 17.6%, and practitioner fault in 13.5%. National solidarity compensated for 48 complaints (24.8%). The final decision of the CCI is not always consistent with the conclusions of the experts mandated by it, illustrating the difficulty in defining the concept of hazards. The authors found that the therapeutic hazards retained and compensated by the national solidarity included decompensated spondylotic myelopathies (15% of the 40 cases) and cauda equina syndromes (30%). As allowed by law, 11.5% of the patients who were not satisfied triggered a classical procedure in a court.

CONCLUSIONS

In the French out-of-court system, trial decisions resulting in rulings of proven medical malpractice are rare, but patients can start a new procedure in the classical courts. The therapeutic hazard remains a subtle definition, which may be problematic and require further discussion between experts and magistrates. In spite of the imperfections, this out-of-court system proposes a major evolution to move patients and medical providers from legal battles to reconciliations.

Management of Incidental Durotomy: Results from a Nationwide Survey Conducted by the French Society of Spine Surgery

OBJECTIVE

To obtain real-life data on the most common practices used for management of incidental durotomy (ID) in France.

METHODS

Data were collected from spinal surgeons using a practice-based online questionnaire. The survey comprised 31 questions on the current management of ID in France. The primary outcome was the identification of areas of consensus and uncertainty on ID follow-up.

RESULTS

A total of 217 surgeons (mainly orthopaedic surgeons and neurosurgeons) completed the questionnaire and were included in the analysis. There was a consensus on ID repair with 94.5% of the surgeons considering that an ID should always be repaired, if repairable, and 97.2% performing a repair if an ID occurred. The most popular techniques were simple suture or locked continuous suture (48.3% vs. 57.8% of surgeons). Nonrepairable IDs were more likely to be treated with surgical sealants than with an endogenous graft (84.9% vs. 75.5%). Almost two thirds of surgeons (71.6%) who adapted their standard postoperative protocol after an ID recommended bed rest in the supine position. Among these, 48.8% recommended 24 hours of bed rest, while 53.5% recommended 48 hours of bed rest. The surgeons considered that the main risk factors for ID were revision surgery (98.6%), patient's age (46.8%), surgeon's exhaustion (46.3%), and patient's weight (21.3%).

CONCLUSIONS

This nationwide survey reflects the lack of a standardized management protocol for ID. Practices among surgeons remain very heterogeneous. Further consensus studies are required to develop a standard management protocol for ID.

Applying an immersive tutorial in virtual reality to learning a new technique

OBJECTIVE

The medical world is continuously evolving, with techniques being created or improved almost daily. Immersive virtual reality (VR) is a technology that could be harnessed to develop tools that meet the educational challenges of this changing environment. We previously described the immersive tutorial, a 3D video (filmed from the first-person point of view), displayed on a VR application. This tool offers access to supplementary educational data in addition to the video. Here we attempt to assess improvement in learning a technique using this new educational format.

MATERIAL AND METHODS

We selected a single neurosurgical technique for the study: external ventricular drainage. We wrote a technical note describing this procedure and produced the corresponding immersive tutorial. We conducted a prospective randomized comparative study with students. All participants read the technical note, and one group used the immersive tutorial as a teaching supplement. The students completed a multiple-choice questionnaire immediately after the training and again at six months.

RESULTS

One hundred seventy-six fourth-year medical students participated in the study; 173 were included in assessing the immediate learning outcomes and 72 were included at the six-month follow-up. The VR group demonstrated significantly better short-term results than the control group (P=0.01). The same trend was seen at six months.

CONCLUSION

To our knowledge, this study presents one of the largest cohorts for VR. The use of the immersive tutorial could enable a large number of healthcare professionals to be trained without the need for expensive equipment.

French Spine Surgery Society guidelines for management of spinal surgeries during COVID-19 pandemic

Since the outbreak of coronavirus disease 2019 (COVID-19) in December 2019 in China, various measures have been adopted in order to attenuate the impact of the virus on the population. With regard to spine surgery, French physicians are devoted to take place in the national plan against COVID-19, the French Spine Surgery Society therefore decided to elaborate specific guidelines for management of spinal disorders during COVID-19 pandemic in order to prioritize management of patients. A three levels stratification was elaborated with Level I: Urgent surgical indications, Level II: Surgical indications associated to a potential loss of chance for the patient and Level III: Non-urgent surgical indications. We also report French experience in a COVID-19 cluster region illustrated by two clinical cases. We hope that the guidelines formulated by the French Spine Surgery Society and the experience of spine surgeons from a cluster region will be helpful in order optimizing the management of patients with urgent spinal conditions during the pandemic.

Middle meningeal artery embolization as an adjuvant treatment to surgery for symptomatic chronic subdural hematoma: a pilot study assessing hematoma volume resorption

Background

Chronic subdural hematoma (CSDH) is a common condition requiring surgical treatment; however, recurrence occurs in 15% of cases at 1 year. Middle meningeal artery (MMA) embolization has recently emerged as a promising treatment to prevent CSDH recurrence.

Objective

To investigate the effect of MMA embolization on hematoma volume resorption (HVR) after surgery in symptomatic patients.

Methods

From April 2018 to October 2018, participants with CSDH requiring surgery were prospectively randomized in a pilot study, and received either surgical treatment alone (ST group) or surgery and adjuvant MMA embolization (ST+MMAE group). The primary outcome was HVR measured on the 3 month CT scan compared with the immediate pre-embolization CT scan. Secondary outcomes were clinical recurrence of CSDH and safety measures.

Results

46 patients were randomized and 41 of these achieved a 3 month follow-up . Twenty-one patients received MMA embolization. At 3 months, the HVR from postsurgical level was higher in the ST+MMAE group (mean difference 17.5 mL, 95% CI 3.87 to 31.16 mL; p=0.015). Two participants presented a CSDH recurrence (one in each group). One patient died (ST group). No MMA embolization-related adverse events were reported.

Conclusion

The addition of MMA embolization to surgery led to an increase in CSDH resorption at 3 months. One recurrence of CSDH was reported in each group, and there were no treatment-related complications.

Hangman's fracture: Management strategy and healing rate in a prospective multi-centre observational study of 34 patients

BACKGROUND

Hangman's fractures account for 15% to 20% of all cervical spine fractures. The grading system developed by Effendi and modified by Levine and Edwards is generally used as the basis for management decisions. Nonetheless, the optimal management remains controversial. The objective of this study was to describe the treatments used in France in patients with hangman's fractures. The complications and healing rates were analysed according to the fracture type and treatment used.

HYPOTHESIS

Among patients with hangman's fracture, those with disc damage must be treated surgically.

MATERIAL AND METHODS

A prospective, multi-centre, observational study was conducted under the aegis of the French Society for Spine Surgery (SociétéFrançaisedeChirurgieRachidienne, SFCR). Patients were included if they had computed tomography (CT) evidence of hangman's fracture. Follow-up data were collected prospectively. Fracture healing was assessed on CT scans obtained 3 and 12 months after the injury. The type of treatment and complications were recorded routinely.

RESULTS

We included 34 patients. The fracture type according to Effendi modified by Levine and Edwards was I in 68% of patients, II in 29% of patients, and III in a single patient (3%). The treatment was non-operative in 21 (62%) patients and surgical in 11 (32%). All 28 patients re-evaluated after 1 year had evidence of fracture healing. The remaining 6 patients were lost to follow-up.

CONCLUSION

Hangman's fracture is associated with low rates of mortality and neurological complications. Non-operative treatment is appropriate in Type I hangman's fracture, with a 100% healing rate in our study. Types II and III are characterised by damage to the ligaments and discs requiring either anterior C2-C3 fusion or posterior C1-C3 screw fixation.

LEVEL OF EVIDENCE

III.

Anterior cervical spine surgical site infection and pharyngoesophageal perforation. Ten-year incidence in 1475 patients

BACKGROUND

Surgical site infection is reputed to be infrequent in anterior cervical spine surgery. Data on pathophysiological mechanism and risk factors are sparse. The relationship between local site infection and pharyngoesophageal perforation is unclear. The present study aimed: (1) to estimate the incidence of surgical site infection in anterior cervical spine surgery, (2) estimate the incidence of associated pharyngoesophageal perforation, and (3) suggest a decision-tree for early management of this two-fold issue.

HYPOTHESIS

Although with very low incidence, anterior cervical spine surgical site infection and pharyngoesophageal perforation are frequently associated.

MATERIAL AND METHODS

A 2-center retrospective study included all anterior cervical spine surgeries between January 1, 2007 and December 31, 2016. Data were provided by the two medical information departments. Patients undergoing anterior revision surgery on the cervical spine were included. Files were analyzed to determine whether the revision surgery was secondary to surgical site infection.

RESULTS

In total, 1475 patients with anterior cervical spine surgery were identified: 1180 in center A (80%) and 295 in center B (20%). The rate of revision surgery for surgical site infection was 0.34% (5/1475). There were 3 cases of pharyngoesophageal perforation (0.2%).

DISCUSSION

The incidence of revision surgery for anterior cervical spine surgical site infection was comparable to rates in the international literature (0.07-1.6%). An association between surgical site infection and pharyngoesophageal perforation was frequent, but not statistically significant. This complication is extremely serious, requiring urgent multidisciplinary management.

LEVEL OF EVIDENCE

IV, retrospective study.

Clinical and radiological outcomes of a cervical cage with integrated fixation

Cervical cages with integrated fixation have been increasingly used in anterior cervical discectomy and fusion (ACDF) to avoid complications associated with anterior cervical plates. The purpose of this paper is to provide 2-year follow-up results of a prospective study after implantation of a cervical cage with an integrated fixation system.This was a prospective multicenter outcome study of 90 patients who underwent ACDF with a cage with integrated fixation. Fusion was evaluated from computed tomography images (CT-images) by an independent laboratory at 2-year follow-up (FU). Clinical and radiological findings were recorded preoperatively and at FU visits and complications were reported.At 24 months, the fusion rate was 93.4%. All average clinical outcomes were significantly improved at 2 years FU compared to baseline: neck disability index (NDI) 18.9% vs 44.4%, visual analog scale (VAS) for arm pain 18.2 mm vs 61.9 mm, VAS for neck pain 23.9 mm vs 55.6 mm. Short form-36 (SF-36) scores were significantly improved. One case of dysphagia, which resolved within 12 months, and 1 reoperation for symptomatic pseudarthrosis were reported. Subsidence with no clinical consequence or reoperation was reported for 5/125 of the implanted cages (4%). There was also 1 case of per-operative vertebral body fracture that did not require additional surgery. Superior and inferior adjacent discs showed no significant change of motion at 2-year FU compared to baseline. Disc height index (DHI) and lordosis were enhanced and these improvements were maintained at 1 year.The ACDF using cages with an integrated fixation system demonstrated reliable clinical and radiological outcomes and a high interbody fusion rate. This rate is comparable to the rate reported in recent series using other implants with integrated fixation, but the present device had a lower complication rate.

C1 fracture: Analysis of consolidation and complications rates in a prospective multicenter series

INTRODUCTION

Three types of C1 fracture have been described, according to location: type 1 (anterior or posterior arc), type 2 (Jefferson: anterior and posterior arc), and type 3 (lateral mass). Stability depends on transverse ligament integrity. The main aim of the present study was to analyze complications and consolidation rates according to fracture type, age and treatment.

MATERIAL AND METHODS

The French Society of Spinal Surgery (SFCR) performed a multicenter prospective study on C1-C2 trauma. All patients with recent fracture diagnosed on CT were included. Consolidation on CT was studied at 3 months and 1 year. Medical, neurologic, infectious and mechanical complications were inventoried using the KEOPS data-base.

RESULTS

Sixty-three of the 417 patients (15.1%) had C1 fracture: type 1 (33.3%), type 2 (38.1%), or type 3 (28.6%). The transverse ligament was intact in 53.9% of cases. Treatment was non-operative in 63.5% of cases, surgical in 27.0%, and surgical after failure of non-operative treatment in 9.5%. There were 8 medical complications, more frequently in patients aged >70 years, following surgery (p<0.0001). The consolidation rate was 84.2% with non-operative treatment, 100% for primary surgery, and 33.3% for secondary surgery (p=0.002). There were 10 cases of non-union, in 4.8% of type 1, 13.6% of type 2 and 33.3% of type 3 fractures (p=0.001).

CONCLUSION

Medical complications showed association with age and with type of treatment. Non-operative treatment was suited to types 1, 2 and 3 with minimal displacement and intact transverse ligament. C1-C2 fusion was suited to displaced unstable type 2 fracture. Displaced type 3 fracture incurred risk of non-union. Early surgery may be recommended.

LEVEL OF EVIDENCE

III.

Surgeon's and patient's radiation exposure during percutaneous thoraco-lumbar pedicle screw fixation: A prospective multicenter study of 100 cases

HYPOTHESIS

Percutaneous pedicle screw fixations (PPSF) are increasingly used in spine surgery, minimizing morbidity through less muscle breakdown but at the cost of intraoperative fluoroscopic guidance that generates high radiation exposure. Few studies have been conducted to measure them accurately.

MATERIAL AND METHODS

The objective of our study is to quantify, during a PPSF carried out in different experimented centers respecting current radiation protection recommendations, this irradiation at the level of the surgeon and the patient. We have prospectively included 100 FPVP procedures for which we have collected radiation doses from the main operator. For each procedure, the doses of whole-body radiation, lens and extremities were measured.

RESULTS

Our results show a mean whole body, extremity and lens exposure dose per procedure reaching 1.7±2.8μSv, 204.7±260.9μSv and 30.5±25.9μSv, respectively. According to these values, the exposure of the surgeon's extremities and lens will exceed the annual limit allowed by the International Commission on Radiological Protection (ICRP) after 2440 and 4840 procedures respectively.

CONCLUSION

Recent European guidelines will reduce the maximum annual exposure dose from 150 to 20mSv. The number of surgical procedures to not reach the eye threshold, according to our results, should not exceed 645 procedures per year. Pending the democratization of neuronavigation systems, the use of conventional fluoroscopy exposes the eyes in the first place. Therefore they must be protected by leaded glasses.

LEVEL OF PROOF

IV, case series.

A Novel Translational Model of Spinal Cord Injury in Nonhuman Primate

Spinal cord injuries (SCI) lead to major disabilities affecting > 2.5 million people worldwide. Major shortcomings in clinical translation result from multiple factors, including species differences, development of moderately predictive animal models, and differences in methodologies between preclinical and clinical studies. To overcome these obstacles, we first conducted a comparative neuroanatomical analysis of the spinal cord between mice, Microcebus murinus (a nonhuman primate), and humans. Next, we developed and characterized a new model of lateral spinal cord hemisection in M. murinus. Over a 3-month period after SCI, we carried out a detailed, longitudinal, behavioral follow-up associated with in vivo magnetic resonance imaging (1H-MRI) monitoring. Then, we compared lesion extension and tissue alteration using 3 methods: in vivo 1H-MRI, ex vivo 1H-MRI, and classical histology. The general organization and glial cell distribution/morphology in the spinal cord of M. murinus closely resembles that of humans. Animals assessed at different stages following lateral hemisection of the spinal cord presented specific motor deficits and spinal cord tissue alterations. We also found a close correlation between 1H-MRI signal and microglia reactivity and/or associated post-trauma phenomena. Spinal cord hemisection in M. murinus provides a reliable new nonhuman primate model that can be used to promote translational research on SCI and represents a novel and more affordable alternative to larger primates.

A Combination of Ex vivo Diffusion MRI and Multiphoton to Study Microglia/Monocytes Alterations after Spinal Cord Injury

Central nervous system (CNS) injury has been observed to lead to microglia activation and monocytes infiltration at the lesion site. Ex vivo diffusion magnetic resonance imaging (diffusion MRI or DWI) allows detailed examination of CNS tissues, and recent advances in clearing procedures allow detailed imaging of fluorescent-labeled cells at high resolution. No study has yet combined ex vivo diffusion MRI and clearing procedures to establish a possible link between microglia/monocytes response and diffusion coefficient in the context of spinal cord injury (SCI). We carried out ex vivo MRI of the spinal cord at different time-points after spinal cord transection followed by tetrahydrofuran based clearing and examined the density and morphology of microglia/monocytes using two-photon microscopy. Quantitative analysis revealed an early marked increase in microglial/monocytes density that is associated with an increase in the extension of the lesion measured using diffusion MRI. Morphological examination of microglia/monocytes somata at the lesion site revealed a significant increase in their surface area and volume as early as 72 hours post-injury. Time-course analysis showed differential microglial/monocytes response rostral and caudal to the lesion site. Microglia/monocytes showed a decrease in reactivity over time caudal to the lesion site, but an increase was observed rostrally. Direct comparison of microglia/monocytes morphology, obtained through multiphoton, and the longitudinal apparent diffusion coefficient (ADC), measured with diffusion MRI, highlighted that axonal integrity does not correlate with the density of microglia/monocytes or their somata morphology. We emphasize that differential microglial/monocytes reactivity rostral and caudal to the lesion site may thus coincide, at least partially, with reported temporal differences in debris clearance. Our study demonstrates that the combination of ex vivo diffusion MRI and two-photon microscopy may be used to follow structural tissue alteration. Lesion extension coincides with microglia/monocytes density; however, a direct relationship between ADC and microglia/monocytes density and morphology was not observed. We highlighted a differential rostro-caudal microglia/monocytes reactivity that may correspond to a temporal difference in debris clearance and axonal integrity. Thus, potential therapeutic strategies targeting microglia/monocytes after SCI may need to be adjusted not only with the time after injury but also relative to the location to the lesion site.

Instrumented Circumferential Fusion in Two Stages for Instable Lumbar Fracture: Long-Term Results of a Series of 74 Patients on Sagittal Balance and Functional Outcomes

OBJECTIVE

To report the radiologic and functional results of a multicenter, prospective case series of patients with comminuted lumbar fractures treated with 2-stage circumferential arthrodesis.

METHODS

A multicenter prospective case series of 74 patients with comminuted lumbar fractures was analyzed. The strategy entailed initial posterior osteosynthesis, followed by physical replacement with an expandable titanium cage filled with autologous bone via retroperitoneal lumbotomy. The mechanism of lesion formation and epidemiologic characteristics were recorded. Clinical and quality-of-life analyses (visual analog scale [VAS], Oswesty Disability Index [ODI], Short Form 12 [SF-12]) were performed over a minimum observation period of 1 year. Radiologic parameters, including deformity measurements, were recorded at each evaluation. Fusion was analyzed by means of a 1-year monitoring scan.

RESULTS

The mean patient age was 38.1 years, and median duration of follow-up was 2.1 years (interquartile range, 1.3-2.9). The distribution of fractures according to the Magerl classification scheme was as follows: A, 64.8%; B, 16.7%; C, 18.5%. At the last follow-up, fusion was considered certain in 57 cases (77%). The mean VAS score was 2.1 ± 1.3, mean ODI was 14.7 ± 8.0, mean SF-12 Physical Component Summary score was 43.2 ± 9.3, and mean SF-12 Mental Component Summary score was 50.8 ± 5.9. Correction of the regional sagittal deformity was significant during the postoperative period, with a mean increase in lordosis of 9.0° (P < 0.0001). The loss of mean correction at the last follow-up (-2.9°) was not significant.

CONCLUSIONS

Circumferential arthrodesis, including posterior osteosynthesis and physical replacement with an expandable cage and autologous graft, is applicable to the treatment of comminuted lumbar fractures. A high rate of fusion was obtained with significant and long-lasting correction of the sagittal deformity. Functional scores measured at 1 year suggest mild disability. The ODI, SF-12, and VAS scores were positively correlated with fusion at the last follow-up.

RNA-Seq Analysis of Microglia Reveals Time-Dependent Activation of Specific Genetic Programs following Spinal Cord Injury

Neurons have inherent competence to regrow following injury, although not spontaneously. Spinal cord injury (SCI) induces a pronounced neuroinflammation driven by resident microglia and infiltrating peripheral macrophages. Microglia are the first reactive glial population after SCI and participate in recruitment of monocyte-derived macrophages to the lesion site. Both positive and negative influence of microglia and macrophages on axonal regeneration had been reported after SCI, raising the issue whether their response depends on time post-lesion or different lesion severity. We analyzed molecular alterations in microglia at several time-points after different SCI severities using RNA-sequencing. We demonstrate that activation of microglia is time-dependent post-injury but is independent of lesion severity. Early transcriptomic response of microglia after SCI involves proliferation and neuroprotection, which is then switched to neuroinflammation at later stages. Moreover, SCI induces an autologous microglial expression of astrocytic markers with over 6% of microglia expressing glial fibrillary acidic protein and vimentin from as early as 72 h post-lesion and up to 6 weeks after injury. We also identified the potential involvement of DNA damage and in particular tumor suppressor gene breast cancer susceptibility gene 1 (Brca1) in microglia after SCI. Finally, we established that BRCA1 protein is specifically expressed in non-human primate spinal microglia and is upregulated after SCI. Our data provide the first transcriptomic analysis of microglia at multiple stages after different SCI severities. Injury-induced microglia expression of astrocytic markers at RNA and protein levels demonstrates novel insights into microglia plasticity. Finally, increased microglia expression of BRCA1 in rodents and non-human primate model of SCI, suggests the involvement of oncogenic proteins after CNS lesion.

From stereoscopic recording to virtual reality headsets: Designing a new way to learn surgery

OBJECTIVE

To improve surgical practice, there are several different approaches to simulation. Due to wearable technologies, recording 3D movies is now easy. The development of a virtual reality headset allows imagining a different way of watching these videos: using dedicated software to increase interactivity in a 3D immersive experience. The objective was to record 3D movies via a main surgeon's perspective, to watch files using virtual reality headsets and to validate pedagogic interest.

MATERIAL AND METHODS

Surgical procedures were recorded using a system combining two side-by-side cameras placed on a helmet. We added two LEDs just below the cameras to enhance luminosity. Two files were obtained in mp4 format and edited using dedicated software to create 3D movies. Files obtained were then played using a virtual reality headset. Surgeons who tried the immersive experience completed a questionnaire to evaluate the interest of this procedure for surgical learning.

RESULTS

Twenty surgical procedures were recorded. The movies capture a scene which is extended 180° horizontally and 90° vertically. The immersive experience created by the device conveys a genuine feeling of being in the operating room and seeing the procedure first-hand through the eyes of the main surgeon. All surgeons indicated that they believe in pedagogical interest of this method.

CONCLUSIONS

We succeeded in recording the main surgeon's point of view in 3D and watch it on a virtual reality headset. This new approach enhances the understanding of surgery; most of the surgeons appreciated its pedagogic value. This method could be an effective learning tool in the future.

Spinal Cervical Meningiomas: The Challenge Posed by Ventral Location

OBJECTIVE

To evaluate the incidence, clinical presentation, operative techniques, and long-term outcome of spinal cervical meningiomas after surgery.

METHODS

Twenty-two patients harboring spinal meningiomas on cervical region were treated between 2004 and 2014 in our department. Diagnosis was made via magnetic resonance imaging and confirmed histologically. Microsurgical resection was performed through different surgical approaches according to location of the tumor. To remove the tumor, the posterior, far-lateral, and combined approaches were used, respectively, in 13 patients (56%), 8 patients (35%), and 2 patients (9%).

RESULTS

The mean follow-up was 40 ± 26.5 months. The most common site of dural attachment of meningioma was ventral or ventrolateral to the spinal cord. Macroscopic resection was considered complete in 55% of cases. Neurologic improvement was observed in 60% of cases. The rate of operative mortality and morbidity was high (26.5%). Five patients underwent postoperative radiotherapy according to the actual recommendation, and the overall recurrence rate was 9%.

CONCLUSIONS

Spinal meningiomas are benign tumors for which advances in imaging tools and microsurgical techniques have yielded better results. The goal of surgery should be the total resection, which significantly decreases the risk of recurrence with an acceptable morbidity. Cervical locations represent a challenge particularly for ventro and ventrolaterally located tumors. Despite the difficulty of performing a complete resection, the results obtained in this work advocate for the use of the far-lateral approach to manage meningiomas locate anterior to the neural axis.

Correlation of in vivo and ex vivo (1)H-MRI with histology in two severities of mouse spinal cord injury

Spinal cord injury (SCI) is a debilitating neuropathology with no effective treatment. Magnetic resonance imaging (MRI) technology is the only method used to assess the impact of an injury on the structure and function of the human spinal cord. Moreover, in pre-clinical SCI research, MRI is a non-invasive method with great translational potential since it provides relevant longitudinal assessment of anatomical and structural alterations induced by an injury. It is only recently that MRI techniques have been effectively used for the follow-up of SCI in rodents. However, the vast majority of these studies have been carried out on rats and when conducted in mice, the contusion injury model was predominantly chosen. Due to the remarkable potential of transgenic mice for studying the pathophysiology of SCI, we examined the use of both in and ex vivo¹H-MRI (9.4 T) in two severities of the mouse SCI (hemisection and over-hemisection) and documented their correlation with histological assessments. We demonstrated that a clear distinction between the two injury severities is possible using in and ex vivo¹H-MRI and that ex vivo MR images closely correlate with histology. Moreover, tissue modifications at a remote location from the lesion epicenter were identified by conventional ex vivo MRI analysis. Therefore, in vivo MRI has the potential to accurately identify in mice the progression of tissue alterations induced by SCI and is successfully implemented by ex vivo MRI examination. This combination of in and ex vivo MRI follow-up associated with histopathological assessment provides a valuable approach for further studies intended to evaluate therapeutic strategies on SCI.

Survey of French spine surgeons reveals significant variability in spine trauma practices in 2013

BACKGROUND

In France, attempts to define common ground during spine surgery meetings have revealed significant variability in clinical practices across different schools of surgery and the two specialities involved in spine surgery, namely, neurosurgery and orthopaedic surgery.

OBJECTIVES

To objectively characterise this variability by performing a survey based on a fictitious spine trauma case. Our working hypothesis was that significant variability existed in trauma practices and that this variability was related to a lack of strong scientific evidence in spine trauma care.

METHODS

We performed a cross-sectional survey based on a clinical vignette describing a 31-year-old male with an L1 burst fracture and neurologic symptoms (numbness). Surgeons received the vignette and a 14-item questionnaire on the management of this patient. For each question, surgeons had to choose among five possible answers. Differences in answers across surgeons were assessed using the Index of Qualitative Variability (IQV), in which 0 indicates no variability and 1 maximal variability. Surgeons also received a questionnaire about their demographics and surgical experience.

RESULTS

Of 405 invited spine surgeons, 200 responded to the survey. Five questions had an IQV greater than 0.9, seven an IQV between 0.5 and 0.9, and two an IQV lower than 0.5. Variability was greatest about the need for MRI (IQV=0.93), degree of urgency (IQV=0.93), need for fusion (IQV=0.92), need for post-operative bracing (IQV=0.91), and routine removal of instrumentation (IQV=0.94). Variability was lowest for questions about the need for surgery (IQV=0.42) and use of the posterior approach (IQV=0.36). Answers were influenced by surgeon specialty, age, experience level, and type of centre.

CONCLUSION

Clinical practice regarding spine trauma varies widely in France. Little published evidence is available on which to base recommendations that would diminish this variability.

Robot-assisted spine surgery: feasibility study through a prospective case-matched analysis

PURPOSE

While image guidance and neuronavigation have enabled a more accurate placement of pedicle implants, they can inconvenience the surgeon. Robot-assisted placement of pedicle screws appears to overcome these disadvantages. However, recent data concerning the superiority of currently available robots in assisting spinal surgeons are conflicting. The aim of our study was to evaluate the percentage of accurately placed pedicle screws, inserted using a new robotic-guidance system.

METHOD

20 Patients were operated on successively by the same surgeon using robotic assistance (ROSA™, Medtech) (Rosa group 10 patients, n = 40 screws) or by the freehand conventional technique (Freehand group 10 patients, n = 50 screws). Patient characteristics as well as the duration of the operation and of exposure to X rays were recorded.

RESULTS

The mean age of patients in each group (RG and FHG) was 63 years. Mean BMI and operating time among the RG and FHG were, respectively, 26 and 27 kg/m(2), and 187 and 119 min. Accurate placement of the implant (score A and B of the Gertzbein Robbins classification) was achieved in 97.3% of patients in the RG (n = 36) and in 92% of those in the FHG (n = 50). Four implants in the RG were placed manually following failed robotic assistance.

CONCLUSION

We report a higher rate of precision with robotic as compared to the FH technique. Providing assistance by permanently monitoring the patient's movements, this image-guided tool helps more accurately pinpoint the pedicle entry point and control the trajectory. Limitations of the study include its small sized and non-randomized sample. Nevertheless, these preliminary results are encouraging for the development of new robotic techniques for spinal surgery.

Adjacent segment disease after anterior cervical interbody fusion: a multicenter retrospective study of 288 patients with long-term follow-up

INTRODUCTION

Cervical discectomy with interbody fusion is a common procedure in spinal surgery. The resultant biomechanical alterations accelerate degeneration of the adjacent segment, but the contribution of natural degeneration to adjacent segment disease is unclear.

OBJECTIVE

To assess the long-term rate of surgery to discs adjacent to cervical interbody fusion; and to assess the associated incidence of cervico-brachial neuralgia and radiological degeneration of adjacent discs.

MATERIAL AND METHOD

A multicenter retrospective study included anterior cervical discectomy patients at a minimum of 10 years' follow-up. Clinical variables comprised pain, use of analgesics and surgical revision. Functional assessment was performed on the Neck Disability Index (NDI). Radiologic degeneration was assessed on the Goffin score based on cervical spine X-ray.

RESULTS

Two hundred and eighty-eight patients were contacted and filled out the clinical questionnaire. Among the patients, 153 underwent radiological reassessment. Mean age was 46 years (range, 16-73 years). Mean follow-up was 14.5 years (12-18 years). The rate of surgical revision on a disc adjacent to the primary level was 5.9%. Frequent attacks of cervico-brachial neuralgia were reported in 20.5% of cases. Radiologic adjacent segment degeneration was found in 81.3% of cases over follow-up. There was a significant correlation between degree of radiologic adjacent segment degeneration and NDI (P=0.02).

DISCUSSION

Degeneration adjacent to discectomy/fusion is partly due to aging. The present findings, however, agree with the literature and indicate accelerated degeneration in adjacent segments. These findings should be taken into account in treatment decision-making and suggest a possible interest of more physiological surgery such as arthroplasty.

LEVEL OF EVIDENCE

IV - Multicenter retrospective study.

Paravertebral glomangioma mimicking a schwannoma

Glomus tumors are rare benign neoplasms usually arising from soft tissues. Surgical removal seems to be the best treatment. Here, we report the case of a 52-year-old female patient referred for chronicback pain, revealing a thoracic paravertebral tumor with no osseous extension. After surgical removal,this tumor turned out to be a glomangioma. Differential diagnosis with other more frequent tumors,such as schwannoma, is particularly difficult. A review of the relevant literature will be presented. A better knowledge of the natural history of those tumors, as well as the therapeutic options available, are necessary for spinal surgeons who may encounter such presentations.

Spinal cord compression due to undiagnosed thoracic meningioma following lumbar surgery in an elderly patient: a case report

As spinal surgery in elderly patients is becoming increasingly frequent, comorbidities likely to be decompensated after such procedures must be kept in mind. We report here the case of an 82-year-old woman who presented rapidly progressive spinal cord compression following lumbar surgery for radiculopathy. Investigations showed a thoracic intradural extramedullary compressive lesion, which after removal turned out to be a meningioma. We suggest that radiculopathy and non-specific degenerative modifications partially masked this lesion, and that lumbar surgery caused this acute neurological deterioration. Therefore, we advice caution in older patients among whom such ambiguous clinical presentation is frequent.

Cervical spine injuries from diving accident: a 10-year retrospective descriptive study on 64 patients

INTRODUCTION

Ninety percent of the lesions resulting from diving injuries affect the cervical spine and are potentially associated with spinal cord injuries. The objective is to determine the most frequent lesion mechanisms. Evaluate the therapeutic alternatives and the biomechanical evolution (kyphotic deformation) of diving-induced cervical spine injuries. Define epidemiological characteristics of diving injuries.

MATERIALS AND METHODS

A retrospective analysis over a period of 10 years was undertaken for patients admitted to the Department of Neurosurgery of Montpellier, France, with cervical spinal injuries due to a diving accident. Patients were re-evaluated and clinical and radiological evaluation follow-ups were done.

RESULTS

This study included 64 patients. Cervical spine injuries resulting from diving predominantly affect young male subjects. They represent 9.5% of all the cervical spine injuries. In 22% of cases, patients presented severe neurological troubles (ASIA A, B, C) at the time of admission. A surgical treatment was done in 85% of cases, mostly using an anterior cervical approach.

DISCUSSION

This is a retrospective study (type IV) with some limitations. The incidence of diving injuries in our region is one of the highest as compared to reports in the literature. Despite an increase of our surgical indications, 55% of these cases end up with a residual kyphotic deformation but there is no relationship between the severity of late vertebral deformity and high Neck Pain and Disability Scale (NPDS) scores.

LEVEL OF EVIDENCE

Level IV, retrospective study.

Isolation and culture of precursor cells from the adult human spinal cord

Our group recently provided evidence for the presence of neural stem cells and/or progenitor cells in the adult human spinal cord. In this chapter, we review materials and methods to harvest high-quality samples of thoracolumbar, lumbar, and sacral adult human spinal cord from brain-dead patients who had agreed to donate their bodies to science for therapeutic and scientific advances. The methods to culture precursor cells from the adult human spinal cord are also described.