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.

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.

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.

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.

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.

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.

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.

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.

Partial Vertebrectomies without Instrumented Stabilization During En Bloc Resection of Primary Bronchogenic Carcinomas Invading the Spine: Feasibility Study and Results on Spine Balance.

OBJECTIVE: It is unknown whether spinal instrumentation is required to prevent deformity after partial vertebrectomy in the treatment of primary bronchogenic carcinomas invading the spine (PBCIS). In this study, we focus on the postoperative spine deformity in patients who underwent operation for partial vertebrectomies without instrumentation during en bloc PBCIS resection. Our objective was to determine whether deformity depends on the type of vertebral resection and if any vertebral resection threshold can be observed to justify additional spinal instrumentation. METHODS: This is a retrospective study, including all patients with PBCIS operated without spinal instrumentation from 2009 to 2018. Partial vertebrectomies were classified into categories A, B, and C depending on vertebral resection. Patients had long-term radiologic follow-up to assess the spine deformity evolution. RESULTS: Eighteen patients were included. The median follow-up was 27 months. Four patients underwent a secondary posterior instrumentation surgical procedure due to progressive spinal deformity. A low-risk group of deformation was characterized as type A resection and type B resection on less than 3 vertebrae. CONCLUSIONS: There are no validated criteria to justify a systematic spinal instrumentation when performing a partial vertebrectomy during en bloc resection of PBCIS. Performed alone without spine instrumentation, both type A and type B resections on less than 3 resected vertebrae were not subject to sagittal and coronal deformity even after a long follow-up, emphasizing that a systematic stabilization is not needed in this low-risk group. These results could help to reduce the perioperative morbidity of these procedures that are usually long and complex.

Mortality, complication, and fusion rates of patients with odontoid fracture: the impact of age and comorbidities in 204 cases.

PURPOSE: The French Society of Spine Surgery (SFCR) conducted a prospective epidemiologic multicenter study. The purpose was to investigate mortality, complication, and fusion rates in patients with odontoid fracture, depending on age, comorbidities, fracture type, and treatment. METHODS: Out of 204 patients, 60 were ≤ 70 years and 144 were > 70 years. Demographic data, comorbidities, treatment types and complications (general medical, infectious, neurologic, and mechanical), and death were registered within the first year. Fractures were classified according to Anderson-D'Alonzo and Roy-Camille on the initial CT. A 1-year follow-up CT was available in 144 patients to evaluate fracture consolidation. RESULTS: Type II and oblique-posterior fractures were the most frequent patterns. The treatment was conservative in 52.5% and surgical in 47.5%. The mortality rate in patients ≤ 70 was 3.3% and 16.7% in patients > 70 years (p = 0.0002). Fracture pattern and treatment type did not influence mortality. General medical complications were significantly more frequent > 70 years (p = 0.021) and after surgical treatment (p = 0.028). Neurologic complications occurred in 0.5%, postoperative infections in 2.0%, and implant-related mechanical complications in 10.3% (associated with pseudarthrosis). Fracture fusion was observed in 93.5% of patients ≤ 70 years and in 62.5% >70 years (p < 0.0001). Pseudarthrosis was present in 31.5% of oblique-posterior fractures and in 24.3% after conservative treatment. CONCLUSIONS: Age and comorbidities influenced mortality and medical complication rates most regardless of fracture type and treatment choice. Pseudarthrosis represented the main complication, which increased with age. Pseudarthrosis was most frequent in type II and oblique-posterior fractures after conservative treatment.

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.

Bow Hunter's Syndrome: Surgical Vertebral Artery Decompression Guided by Dynamic Intraoperative Angiography.

BACKGROUND: Bow hunter's syndrome is a symptomatic vertebrobasilar insufficiency resulting from a rotational stenosis or occlusion of a dominant vertebral artery (VA). The VA is dynamically compressed by cervical osteoarthritis (discovertebral structure or osteophytes) during head rotation or neck extension. Diagnosis is based on dynamic computed tomography angiography and confirmed with dynamic catheter angiography. Surgery tends to be the best treatment option in most cases. Dynamic intraoperative assessment of VA decompression seems to improve surgical results but remains poorly evaluated in the literature. CASE DESCRIPTION: A 70-year-old man with bow hunter's syndrome related to left VA compression by C3-4 osteophyte protrusion presented with syncopal episodes during left head rotation. Bow hunter's syndrome was successfully managed with an anterior transuncal surgical decompression of the left VA and C3-4 fusion. Surgical decompression was guided by dynamic intraoperative catheter angiography and secured with an intra-arterial remodeling balloon placed just before surgery. The patient was symptom-free after surgery. CONCLUSIONS: Surgical decompression guided by dynamic intraoperative catheter angiography leads to selective VA release and allows real-time assessment of the efficacy of the decompression. This multidisciplinary treatment involving neurosurgical and neuroradiologic teams is a simple and effective treatment. Dynamic intraoperative catheter angiography is an essential guide to perform selective decompression of the VA, and implementation of an intra-arterial remodeling balloon can improve the safety of surgery making this method valuable compared with other intraoperative assessment techniques, such as Doppler ultrasound and indocyanine green fluorescent videography.

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.

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.