Pseudoarthrosis after spinal fusion is an important complication leading to revision spine surgeries. Iliac Crest Bone Graft is considered the gold standard, but with limited availability and associated co-morbidities, spine surgeons often utilize alternative bone grafts. Determine the non-inferiority of a novel submicron-sized needle-shaped surface biphasic calcium phosphate (BCP<µm) as compared to autograft in instrumented posterolateral spinal fusion. Adult patients indicated for instrumented posterolateral spinal fusion of one to six levels from T10-S2 were enrolled at five participating centers. After instrumentation and preparation of the bone bed, the randomized allocation side of the graft type was disclosed. One side was grafted with 10cc of autograft per level containing a minimum of 50% iliac crest bone. The other side was grafted with 10cc of BCP<µm granules standalone (without autograft or bone marrow aspirate). In total, 71 levels were treated. Prospective follow-up included adverse events, Oswestry Disability Index (ODI), and a fine-cut Computerized Tomography (CT) at one year. Fusion was systematically scored as fused or not fused per level per side by two spine surgeons blinded for the procedure. The first fifty patients enrolled are included in this analysis (mean age: 57 years; 60% female and 40% male). The diagnoses included deformity (56%), structural instability (28%), and instability from decompression (20%). The fusion rate determined by CT for BCP<μm was 76.1%, which compared favorably to the autograft fusion rate of 43.7%. Statistical analysis through binomial modeling showed that the odds of fusion of BCP<μm was 2.54 times higher than that of autograft. 14% of patients experienced a procedure or possible device-related severe adverse event and there were four reoperations. Oswestry Disability Index (ODI) score decreased from a mean of 46.0 (±15.0) to a mean of 31.7 (±16.9), and 52.4% of patients improved with at least 15-point decrease. This data, aiming to determine non-inferiority of standalone BCP<μm as compared to autograft for posterior spinal fusions, is promising. Ongoing studies to increase the power of the statistics with more patients are forthcoming

Neurological complications in oncological and degenerative spine surgery represent one of the most feared risks of these procedures. Multimodal intraoperative neurophysiological monitoring (IONM) mainly uses methods to detect changes in the patient's neurological status in a timely manner, thus allowing actions that can reverse neurological deficits before they become irreversible. The utopian goal of spinal surgery is the absence of neurological complications while the realistic goal is to optimize the responses to changes in neuromonitoring such that permanent deficits occur less frequently as possible. In 2014, an algorithm was proposed in response to changes in neuromonitoring for deformity corrections in spinal surgery. There are several studies that confirm the positive impact that a checklist has on care. The proposed checklist has been specifically designed for interventions on stable columns which is significantly different from oncological and degenerative surgery. The goal of this project is to provide a checklist for oncological and degenerative spine surgery to improve the quality of care and minimize the risk of neurological deficit through the optimization of clinical decision-making during periods of intraoperative stress or uncertainty. After a literature review on risk factors and recommendations for responding to IONM changes, 3 surveys were administered to 8 surgeons with experience in oncological and degenerative spine surgery from 5 hospitals in Italy. In addition, anesthesiologists, intraoperative neuro-monitoring teams, operating room nurses participated. The members participated in the optimization and final drafting of the checklist. The authors reassessed and modified the checklist during 3 meetings over 9 months, including a clinical validation period using a modified Delphi process. A checklist containing 28 items to be considered in responding to the changes of the IONM was created. The checklist was submitted for inclusion in the new recommendations of the Italian Society of Clinical Neurophysiology (SINC) for intraoperative neurophysiological monitoring. The final checklist represents the consensus of a group of experienced spine surgeons. The checklist includes the most important and high-performance items to consider when responding to IONM changes in patients with an unstable spine. The implementation of this checklist has the potential to improve surgical outcomes and patient safety in the field of spinal surgery

Introduction:. Most of the published papers on AI based diagnosis have focused on the algorithm's diagnostic performance in a ‘binary’ setting (i.e. disease vs no disease). However, no study evaluated the actual value for the clinicians of an AI based approach in diagnostic. Detection of Traumatic thoracolumbar (TL) fractures is challenging on planar radiographs, resulting in significant rates of missed diagnoses (30-60%), thus constituting a field in which a performance improvement is needed. Aim of this study is therefore to evaluate the value provided by AI generated saliency maps (SM), i.e. the maps that highlight the AI identified region of interests. Methods:. An AI model aimed at identifying TL fractures on plain radiographs was trained and tested on 567 single vertebrae images. Three expert spine surgeons established the Ground Truth (GT) using CT and MRI to confirm the presence of the fracture. From the test set, 12 cases (6 with a GT of fracture and 6 with a GT of no fracture, associated with varying levels of algorithm confidence) were selected and the corresponding SMs were generated and shown to 7 independent evaluators with different grade of experience; the evaluators were requested to: (1) identify the presence or absence of a fracture before and after the saliency map was shown; (2) grade, with a score from 1 (low) to 6 (high) the pertinency (correlation between the map and the human diagnosis), and the utility (the perceived utility in confirming or not the initial diagnosis) of the SM. Furthermore, the usefulness of the SM was evaluated through the rate of correct change in diagnosis after the maps had been shown. Finally, the obtained scores were correlated with the algorithm confidence for the specific case. Results:. Of the selected maps, 8 had an agreement between the AI diagnosis and the GT, while in 4 the diagnosis was discordant (67% accuracy). The pertinency of the map was found higher when the AI diagnosis was the same as the GT and the human diagnosis (respectively p-value = .021 and <.000). A positive and significant correlation between the AI confidence score and the perceived utility (Spearman: 27%, p-value=.0-27) was found. Furthermore, evaluator with experience < 5 year found the maps more useful than the experts (z-score=2.004; p-value=.0455). Among the 84 evaluation we found 12 diagnostic errors in respect to the GT, 6 (50%) of which were reverted after the saliency map evaluation (z statistic = 1.25 and p-value = .21). Discussion:. The perceived utility of AI generated SM correlate with the model confidence in the diagnosis. This highlights the fact that to be considered helpful, the AI must provide not only the diagnosis but also the case specific confidence. Furthermore, the perceived utility was higher among less experienced users, but overall, the SM were useful in improving the human diagnostic accuracy. Therefore, in this setting, the AI enhanced approach provides value in improving the human performance

There is an inherent risk of iatrogenic new neurological deficit (NND) arising at the spinal cord, cauda equina and nerve root during spinal surgery. Intraoperative neurophysiological monitoring (IONM) can be employed to preserve spinal cord function during spinal surgery. IONM techniques include somatosensory and motor evoked potentials, amongst others. A Canadian survey of 95 spinal surgeons showed that 62.1% used IONM and a similar survey in France of 117 spinal surgeons showed that only 36% used IONM. Unavailability was a common reason for its disuse. Current literature by the British Society of Clinical Neurophysiology has outlined the importance of IONM in preventing NND and the need for the implementation of guidelines for IONM. The lack of an established guideline has resulted in a varied approach in the use of IONM in England. There has been no previous attempt to ascertain the current use of IONM in England. Our study is aimed at assessing the variability of the use of IONM in England as well as identifying the rationale amongst surgeons that dictate their use of IONM. We are in the process of investigating the indications of use of IONM for cervical and lumbar spine procedures in 252 spinal surgeons from 33 hospitals with spinal services. Our survey will illustrate the current use of IONM in spinal surgery in England. It will highlight some of the reasons for the variability of use of IONM and identify factors that can contribute to a more standardised use of IONM in spinal surgery

Introduction and Objective. Up to 30% of thoracolumbar (TL) fractures are missed in the emergency room. Failure to identify these fractures can result in neurological injuries up to 51% of the casesthis article aimed to clarify the incidence and risk factors of traumatic fractures in China. The China National Fracture Study (CNFS. Obtaining sagittal and anteroposterior radiographs of the TL spine are the first diagnostic step when suspecting a traumatic injury. In most cases, CT and/or MRI are needed to confirm the diagnosis. These are time and resource consuming. Thus, reliably detecting vertebral fractures in simple radiographic projections would have a significant impact. We aim to develop and validate a deep learning tool capable of detecting TL fractures on lateral radiographs of the spine. The clinical implementation of this tool is anticipated to reduce the rate of missed vertebral fractures in emergency rooms. Materials and Methods. We collected sagittal radiographs, CT and MRI scans of the TL spine of 362 patients exhibiting traumatic vertebral fractures. Cases were excluded when CT and/or MRI where not available. The reference standard was set by an expert group of three spine surgeons who conjointly annotated (fracture/no-fracture and AO Classification) the sagittal radiographs of 171 cases. CT and/or MRI were used confirm the presence and type of the fracture in all cases. 302 cropped vertebral images were labelled “fracture” and 328 “no fracture”. After augmentation, this dataset was then used to train, validate, and test deep learning classifiers based on the ResNet18 and VGG16 architectures. To ensure that the model's prediction was based on the correct identification of the fracture zone, an Activation Map analysis was conducted. Results. Vertebras T12 to L2 were the most frequently involved, accounting for 48% of the fractures. Accuracies of 88% and 84% were obtained with ResNet18 and VGG16 respectively. The sensitivity was 89% with both architectures but ResNet18 had a significantly higher specificity (88%) compared to VGG16 (79%). The fracture zone used was precisely identified in 81% of the heatmaps. Conclusions. Our AI model can accurately identify anomalies suggestive of TL vertebral fractures in sagittal radiographs precisely identifying the fracture zone within the vertebral body

Introduction and Objective. Posterior and transforaminal lumbar interbody fusion (PLIF, TLIF) represent the most popular techniques in performing an interbody fusion amongst spine surgeons. Pseudarthrosis, cage migration, subsidence or infection can occur, with subsequent failed surgery, persistent pain and patient’ bad quality of life. The goal of revision fusion surgery is to correct any previous technical errors avoiding surgical complications. The most safe and effective way is to choose a naive approach to the disc. Therefore, the anterior approach represents a suitable technique as a salvage operation. The aim of this study is to underline the technical advantages of the anterior retroperitoneal approach as a salvage procedure in failed PLIF/TLIF analyzing a series of 32 consecutive patients. Materials and Methods. We performed a retrospective analysis of patients’ data in patients who underwent ALIF as a salvage procedure after failed PLIF/TLIF between April 2014 to December 2019. We recorded all peri-operative data. In all patients the index level was exposed with a minimally invasive anterior retroperitoneal approach. Results. Thirty-two patients (average age: 46.4 years, median age 46.5, ranging from 21 to 74 years hold- 16 male and 16 female) underwent salvage ALIF procedure after failed PLIF/TLIF were included in the study. A minimally invasive anterior retroperitoneal approach to the lumbar spine was performed in all patients. In 6 cases (18.7%) (2 infection and 4 pseudarthrosis after stand-alone IF) only anterior revision surgery was performed. A posterior approach was necessary in 26 cases (81.3%). In most of cases (26/32, 81%) the posterior instrumentation was overpowered by the anterior cage without a previous revision. Three (9%) intraoperative minor complications after anterior approach were recorded: 1 dural tear, 1 ALIF cage subsidence and 1 small peritoneal tear. None vascular injuries occurred. Most of patients (90.6%) experienced an improvement of their clinical condition and at the last follow-up no mechanical complication occurred. Conclusions. According to our results, we can suggest that a favourable clinical outcome can firstly depend from technical reasons an then from radiological results. The removal of the mobilized cage, the accurate endplate and disc space preparation and the cage implant eliminate the primary source of pain reducing significantly the axial pain, helping to realise an optimal bony surface for fusion and enhancing primary stability. The powerful disc distraction given by the anterior approach allows inserting large and lordotic cages improving the optimal segmental lordosis restoration

Introduction. Guidelines from the North American Spine Society (2009 and 2013) are the best evidence-based instructions on venous thromboembolism (VTE) and antibiotic prophylaxis in spinal surgery. NICE guidelines exist for VTE prophylaxis but do not specifically address spinal surgery. In addition, the ruling of the UK Supreme Court in 2015 resulted in new guidance on consent being published by the Royal College of Surgeons of England (RCSEng). This study assesses our compliance in antibiotic, VTE prophylaxis and consent in spinal surgery against both US and UK standards. Methods. Retrospective review of spinal operations performed between August and December 2016. Case notes, consent forms and operation notes were analysed for consent, peri-operative antibiotic prescribing and post-operative VTE instructions. Results. Four Spinal surgeons performed 45 operations during this period. 31 patients (69%) received a copy of the signed consent with this process being formally documented in 22 (71%) of those cases. All patients were consented by a competent surgeon. 82% of cases consented prior to the date of procedure were countersigned on the day of operation. There was a mean time of 25.3 days between initial consent and operation (Range: 0–170). 37 (82%) cases had clear instructions for VTE and antibiotic prophylaxis. All prescribed post-operative antibiotics were administered. Discussion. The North American Guidelines state that prophylactic antibiotic is appropriate in all spinal surgery with prolonged cases requiring intraoperative re-dosing and only complex cases needing a postoperative regimen. Eight patients underwent a complex procedure and 7 appropriately received postoperative antibiotics. Of the 29 patients that underwent a simple procedure, 12 did not receive post-operative regimen, in line with the guidelines. However, the remainder 17 were over treated. The US Guidelines recommend mechanical VTE prophylaxis only in elective spinal surgery except in high risk patients. All our patients received VTE mechanical prophylaxis. RCSEng guidelines require consent being taken prior to procedure by a competent surgeon and confirmed on day of procedure. All patients in our cohort were consented prior to the date of operation allowing time for considering options and independent research. 82% of patients had consent confirmed on day of operation. Conclusion. This study demonstrates that we met guideline advice for all patients with regards VTE prophylaxis. We have a tendency to over treat with post-operative antibiotics and not all patients had their consent confirmed on day of procedure but was consented well before day of operation. North America still lead the way with guidelines on spinal surgery to which we should adhere, with NICE guidelines providing limited instructions. New consenting guidelines from RCSEng may not be currently widely known and thus should be a source of education for all surgeons

Background. Although the aetiology of chronic low back pain (CLBP) is unknown, it is suggested that several subgroups among CLBP-patients might be identified who are likely to benefit from different interventions. The results of these interventions might be improved by matching interventions to patient characteristics. Purpose. The purpose of this longitudinal study is to determine which subgroup of CLBP-patients benefits most from the short, intensive pain management program of RealHealth_NL. Methods. A prospective cohort of 524 selected consecutive CLBP-patients was followed. Potential predictive indicators included demographic characteristics, functional disability, experienced pain and cognitive behavioural factors as measured at pre-treatment assessment. The outcome is defined as one year improvement in functional disability. A successful outcome is a value as seen in healthy populations. The two-week residential program is in line with recommendations in international guidelines, based on cognitive behavioural principles and delivered in collaboration with orthopedic spine surgeons. Results. Multivariate logistic regression revealed pre-treatment being employed (OR 3.609 [95%CI 1.795–7.256]), and functional disability (OR 0.943 [95%CI 0.921–0.965]) as significant predictive factors of a successful outcome in functional disability at one year follow-up. Conclusion. The results imply that CLBP-patients, who are employed, and less disabled at pre-treatment assessment, who participated in the RealHealth_NL program, are consistently associated with one year follow-up improvement of functional disability toward normal values. A small set of indicators is more easily identified and addressed and CLBP-patients who are more likely to benefit from the program could be given a higher entry priority. Conflict of Interest: J O'Dowd owns shares in RealHealth_NL; Research Development & Education independent research organisation; Sint Maartenskliniek health care provider and referral organisation. Source of funding: None. This abstract has not been previously published in whole or substantial part nor has it been presented previously at a national meeting

Summary. There is emerging evidence of successful application of IOCS and leucocyte depletion filter in removing tumour cells from blood salvaged during various oncological surgeries. Research on the use of IOCS-LDF in MSTS is urgently needed. Introduction. Intra-operative cell salvage (IOCS) can reduce allogeneic blood transfusion requirements in non-tumour related spinal surgery. However, IOCS is deemed contraindicated in metastatic spine tumor surgery (MSTS) due to risk of tumour dissemination. Evidence is emerging from different surgical specialties describing the use of IOCS in cancer surgery. We wanted to investigate if IOCS is really contraindicated in MSTS. We hereby present a systematic literature review to answer the following questions: 1. Has IOCS ever been used in MSTS? 2. Is there any evidence to support the use of IOCS in other oncologic surgeries?. Methods. A systematic review of the English literature was conducted using computer searching of databases: Medline, Embase, the Cochrane Central Register of Controlled Trials for articles published between 1 January 1986 and 31 Dec 2012. Results. Question 1: A comprehensive literature search did not provide any publication describing the use of IOCS in MSTS. The application of IOCS in MSTS has never been described before. Question 2: Our systematic review shows that the use of IOCS has been extensively investigated in patients undergoing surgery for gynaecological, lung, urological, gastrointestinal, and hepatobiliary cancers. The literature review considered 281 abstracts from the initial search. After consideration by consensus, 30 articles were included in the final analysis. We included in our review -prospective, retrospective studies and in vitro studies. The selected articles were then classified according to the surgical specialty: gynaecological, lung, urological, gastrointestinal, and hepatobiliary cancers and type of studies: reinfusion studies, non-reinfusion studies and in vitro studies. 23 Reinfusion studies: Studies where salvaged blood was actually re-infused into patients and analyzed on the basis of clinical outcomes like survival, recurrence, metastasis rates, and transfusion requirements, etc. IOCS has been extensively investigated in several large cohort studies and large case series with considerable follow-up duration across urological, gynaecological, hepatobiliary and gastrointestinal cancers. Patients receiving salvaged blood have been shown to perform as well or better across a variety of clinical outcome measures as mentioned above. 2 in vitro studies and 5 non-reinfusion studies: Studies where salvaged blood was not re-infused into patients but was analyzed for the presence or viability of tumour cells in the processed blood. They consistently demonstrated the utility of LDF in either greatly reducing the number of tumour cells or even completely eradicating tumour cells from blood-tumour admixtures or salvaged blood. This provides the “proof-of-concept” that LDF is able and is effective in removing tumour cells from blood. Discussion/Conclusion. There is strong evidence that LDF can safely remove tumour cells from salvaged blood. IOCS in patients undergoing cancer surgery is not associated with any adverse clinical outcomes. The reluctance of spine surgeons to use IOCS in MSTS appears to be unsupported. There is ample evidence supporting the use of IOCS in oncological surgeries. Research is needed to evaluate the application of IOCS in MSTS

In a study on ten fresh human cadavers we examined the change in the height of the intervertebral disc space, the angle of lordosis and the geometry of the facet joints after insertion of intervertebral total disc replacements. SB III Charité prostheses were inserted at L3-4, L4-5, and L5-S1. The changes studied were measured using computer navigation sofware applied to CT scans before and after instrumentation.

After disc replacement the mean lumbar disc height was doubled (p < 0.001). The mean angle of lordosis and the facet joint space increased by a statistically significant extent (p < 0.005 and p = 0.006, respectively). By contrast, the mean facet joint overlap was significantly reduced (p < 0.001). Our study indicates that the increase in the intervertebral disc height after disc replacement changes the geometry at the facet joints. This may have clinical relevance.

A rat model of lumbar root constriction with an additional sympathectomy in some animals was used to assess whether the sympathetic nerves influenced radicular pain. Behavioural tests were undertaken before and after the operation.

On the 28th post-operative day, both dorsal root ganglia and the spinal roots of L4 and L5 were removed, frozen and sectioned on a cryostat (8 μm to 10 μm). Immunostaining was then performed with antibodies to tyrosine hydroxylase (TH) according to the Avidin Biotin Complex method. In order to quantify the presence of sympathetic nerve fibres, we counted TH-immunoreactive fibres in the dorsal root ganglia using a light microscope equipped with a micrometer graticule (10 x 10 squares, 500 mm x 500 mm). We counted the squares of the graticule which contained TH-immunoreactive fibres for each of five randomly-selected sections of the dorsal root ganglia.

The root constriction group showed mechanical allodynia and thermal hyperalgesia. In this group, TH-immunoreactive fibres were abundant in the ipsilateral dorsal root ganglia at L5 and L4 compared with the opposite side. In the sympathectomy group, mechanical hypersensitivity was attenuated significantly.

We consider that the sympathetic nervous system plays an important role in the generation of radicular pain.