The Positive Side Effect of Anterior Cervical Decompression and Fusion on Axial Neck Pain.

STUDY DESIGN: Observational Cohort Study. OBJECTIVES: This study aims to comprehensively assess the outcomes of anterior cervical spine surgery in patients who have undergone surgical intervention for radiculopathy or myelopathy, with a specific focus on the surgery's impact on axial neck pain. METHODS: Data from an institutional spine surgery registry were analyzed for patients who underwent anterior cervical spine surgery between January 2016 and March 2022. Patient demographics, clinical variables, and outcome measures, including the Neck Disability Index (NDI), numeric rating scales for neck and arm pain (NRS-Neck and NRS-Arm), and 36-Item Short Form Health Survey (SF-36) scores, were collected. Statistical analysis included paired t-tests, chi-squared tests, and multivariate linear regression. RESULTS: Of 257 patients, 156 met the inclusion criteria. Patients showed significant improvement in NDI, NRS-Neck, NRS-Arm, SF-36 (Physical and Mental components), and all changes exceeded the minimum clinically important difference. Multivariate regression revealed that lower preoperative physical and mental component scores and higher preoperative NRS-Neck predicted worse NDI scores at follow-up. CONCLUSIONS: This study underscores that anterior cervical fusion not only effectively alleviates arm pain and disability but also has a positive impact on axial neck pain, which may not be the primary target of surgery. Our findings emphasize the potential benefits of surgical intervention when neck pain coexists with neurologic compression. This contribution adds to the growing body of evidence emphasizing the importance of precise diagnosis and patient selection. Future research, ideally focusing on patients with isolated neck pain, should further explore alternative surgical approaches to enhance treatment options.

Is neck pain treatable with surgery?

INTRODUCTION: Neck pain is one of the most common complaints in clinical practice and can be caused by a wide variety of conditions. While cervical spine surgery is a well-accepted option for radicular pain and myelopathy, surgery for isolated neck pain is controversial. The identification of the source of pain is challenging and subtle, and misdiagnosis can lead to inappropriate treatment. MATERIALS AND METHODS AND RESULTS: We conducted a thorough literature review to discuss and compare different causes of neck pain. We then supplemented the literature with our senior author's expert analysis of treating cervical spine pathology. CONCLUSIONS: This study provides an in-depth discussion of neck pain and its various presentations, as well as providing insight into treatment strategies and diagnostic pearls that may prevent mistreatment of cervical spine pathology.

Complications in endoscopic spine surgery: a systematic review.

PURPOSE: This systematic review aims to investigate the complication rate of endoscopic spine surgeries, stratifying them by technique, district and kind of procedure performed. METHODS: This study was conducted according to the PRISMA statement. The literature search was conducted in MEDLINE, CINAHL, EMBASE, Cochrane Register, OTseeker and ScienceDirect database. Types of studies included were observational studies (cohort studies, case-control studies and case series) and randomised or quasi-randomised clinical with human subjects. No restrictions on publication year were applied. Repeated articles, reviews, expert's comments, congress abstracts, technical notes and articles not in English were excluded. Several data were extracted from the articles. In particular, data of perioperative (≤ 3 months) and late (> 3 months) complications were collected and grouped according to: (1) surgical technique [uniportal full-endoscopic spine surgery (UESS) or unilateral biportal endoscopic spine surgery (UBESS)]; (2) spinal district treated [cervical, thoracic or lumbar] and (3) type of procedure [discectomy/decompression or fusion]. Complication analysis was performed in subgroups with at least 100 patients to have clinically meaningful statistical validity. RESULTS: A total of 117 full-text articles were assessed for eligibility. Of the 117 records included, 95 focused their research on UESS (14 LOE V, 33 LOE IV, 43 LOE III and five LOE II) and 23 on UBESS (three LOE V, eight LOE IV, 10 LOE III and two LOE II). A total of 20,020 patients were extracted to investigate the incidence of different perioperative and late complications, 10,405 for UESS and 9615 for UBESS. CONCLUSION: The present study summarises the complications reported in the literature for spinal endoscopic procedures. On the one hand, the most relevant described were perioperative complications (transient neurological deficit, dural tear and dysesthesia) that are especially meaningful for endoscopic discectomy and decompression. On the other hand, late complications, such as mechanical implant failure, are more common in endoscopic interbody fusion. LEVEL OF EVIDENCE: I.

Diagnostic Approach and Differences between Spinal Infections and Tumors.

STUDY DESIGN: A systematic review of the literature about differential diagnosis between spine infection and bone tumors of the spine. BACKGROUND AND PURPOSE: The differential diagnosis between spine infection and bone tumors of the spine can be misled by the prevalence of one of the conditions over the other in different areas of the world. A review of the existing literature on suggestive or even pathognomonic imaging aspects of both can be very useful for correctly orientating the diagnosis and deciding the most appropriate area for biopsy. The purpose of our study is to identify which imaging technique is the most reliable to suggest the diagnosis between spine infection and spine bone tumor. METHODS: A primary search on Medline through PubMed distribution was made. We identified five main groups: tuberculous, atypical spinal tuberculosis, pyogenic spondylitis, and neoplastic (primitive and metastatic). For each group, we evaluated the commonest localization, characteristics at CT, CT perfusion, MRI, MRI with Gadolinium, MRI diffusion (DWI) and, in the end, the main features for each group. RESULTS: A total of 602 studies were identified through the database search and a screening by titles and abstracts was performed. After applying inclusion and exclusion criteria, 34 articles were excluded and a total of 22 full-text articles were assessed for eligibility. For each article, the role of CT-scan, CT-perfusion, MRI, MRI with Gadolinium and MRI diffusion (DWI) in distinguishing the most reliable features to suggest the diagnosis of spine infection versus bone tumor/metastasis was collected. CONCLUSION: Definitive differential diagnosis between infection and tumor requires biopsy and culture. The sensitivity and specificity of percutaneous biopsy are 72% and 94%, respectively. Imaging studies can be added to address the diagnosis, but a multidisciplinary discussion with radiologists and nuclear medicine specialists is mandatory.

Oblique, Unilateral, or Bilateral Rods Configurations for Single-Level Interbody Fusion and Posterior Spinal Fixation: A Finite Element Study.

AIM: To compare three different posterior mono-segmental instrumented models with a Lateral Lumbar Interbody Fusion (LLIF) cage in L4-L5 based on finite element (FE) analysis. MATERIAL AND METHODS: Three different configurations of posterior instrumentation were created: 1. Bilateral posterior screws with 2 rods: Bilateral (B); 2. Left posterior rod and left pedicle screws in L4-L5: Unilateral (U); 3. Oblique posterior rod, left pedicle screw in L4, and right pedicle screw in L5: Oblique (O). The models were compared regarding the range of motion (ROM), stresses in the L4 and L5 pedicle screws, and posterior rods. RESULTS: The Oblique and Unilateral models showed a lower decrease in ROM than the Bilateral model (O vs U vs B; 92% vs 95% vs 96%). In the L4 screw, a higher stress level was identified in the O than in the B model. Still, lower if compared to U. In the L5 screw, the highest stress values were observed with the O model in extension and flexion and the U model in lateral bending and axial rotation. The highest stress values for the rods were observed for the O model in extension, flexion, and axial rotation and the U model in lateral bending. CONCLUSION: The FE analysis showed that the three configurations significantly reduced the ROM. The stress analysis identified a substantially higher value for the rod and pedicle screws in oblique or unilateral configuration systems compared to the standard bilateral one. In particular, the oblique configuration has stress properties similar to the unilateral in lateral bending and axial rotation but is significantly higher in flexion-extension.

The burden of preoperative fear-avoidance beliefs in workers after thoracic and lumbar spine surgery: a 2-year follow-up study.

ABSTRACT: Spinal disorders are the main reasons for sick leave and early retirement among the working population in industrialized countries. When "red flags" are present, spine surgery is the treatment of choice. However, the role of psychosocial factors such as fear-avoidance beliefs in spine surgery outcomes is still debated. The study aims to investigate whether patients presenting high or low levels of fear-avoidance thoughts before the spine surgery reported different surgical results and return-to-work rates over 2 years. From an institutional spine surgery registry, workers surgically treated with a preoperative score in the Oswestry Disability Index (ODI) higher than 20/100 and provided ODI questionnaires, return-to-work status at 3-, 6-, 12-, and 24-month follow-ups were analyzed. A total of 1769 patients were stratified according to the work subscale of the Fear-Avoidance Beliefs Questionnaire (FABQ-W) in high fear (FABQ-W ≥ 34/42) or low fear (FABQ-W < 34/42). Multivariate regression was used to search for preoperative factors, which might interact with FABQ-W. The higher-fear group showed a different recovery pattern, with higher levels of disability according to the ODI (total score, absolute change, frequency of clinically relevant change, and disability categories) and lower return-to-work ratios over the 24-month follow-up. High fear, high disability, greater age, female gender, smoking, and worse physical status at baseline were associated with worse ODI outcomes 2 years after the surgery. In summary, fear-avoidance beliefs significantly influence the speed and the entity of surgical outcomes in the working population. However, the contribution of FABQ-W in predicting long-term disability levels was limited.

The sitting vs standing spine.

Background: Planning of surgical procedures for spinal fusion is performed on standing radiographs, neglecting the fact that patients are mostly in the sitting position during daily life. The awareness about the differences in the standing and sitting configuration of the spine has increased during the last years. The purpose was to provide an overview of studies related to seated imaging for spinal fusion surgery, identify knowledge gaps and evaluate future research questions. Methods: A literature search according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) extension for Scoping Reviews (PRISMASc) was performed to identify reports related to seated imaging for spinal deformity surgery. A summary of the finding is presented for healthy individuals as well as patients with a spinal disorder and/or surgery. Results: The systematic search identified 30 original studies reporting on 1) the pre- and postoperative use of seated imaging of the spine (n=12), 2) seated imaging of the spine for non - surgical evaluation (n=7) and 3) seated imaging of the spine among healthy individuals (12). The summarized evidence illuminates that sitting leads to a straightening of the spine decreasing thoracic kyphosis (TK), lumbar lordosis (LL), the sacral slope (SS). Further, the postural change between standing and sitting is more significant on the lower segments of the spine. Also, the adjacent segment compensates the needed postural change of the lumbar spine while sitting with hyperkyphosis. Conclusions: The spine has a different configuration in standing and sitting. This systematic review summarizes the current knowledge about such differences and reveals that there is minimal evidence about their consideration for surgical planning of spinal fusion surgery. Further, it identifies gaps in knowledge and areas of further research.

Clinical and radiographic performance of indirect foraminal decompression with anterior retroperitoneal lumbar approach for interbody fusion (ALIF).

STUDY DESIGN: Retrospective study BACKGROUND: Indirect decompression with ALIF allows the restoration of the disk and foraminal height with limited soft tissue damage. However, it does not offer a direct view of the neural structure and a direct intraoperative assessment of the results of the decompression is not possible. For this reason, ALIF is often accompanied by posterior, direct decompression. So far, there is no consensus on the effects of indirect decompression alone for L5-S1 foraminal stenosis. OBJECTIVE: Evaluation of the clinical and mechanical performance of indirect decompression with anterior lumbar interbody fusion (ALIF) in L5-S1 foraminal stenosis. METHODS: All patients who underwent ALIF at our institution and had a minimum follow-up of six months were assessed for inclusion. Radiographic parameters (anterior and posterior disc height, foraminal height and surface, L5-S1 angle, pelvic incidence, pelvic tilt and lumbar lordosis) and clinical data (Oswestry Disability Index - ODI and Numeric Rating Scale - NRS) before ALIF and at the last follow-up were compared. A regression analysis was performed to investigate the correlation between radiographic and clinical outcomes. RESULTS: Thirty-four patients were available for the study (55.9% female, mean age 53.4±11.5 years), mean follow-up was 26.4±11.1 months. At the last follow-up, a significant increase in foraminal height (14.6±4.0 vs. 17.9±3.9 mm, p<0.001), posterior disc height (6.5±2 vs. 9.1±2 mm, p<0.001) was observed. ODI and NRS back and leg improved significantly. The NRS leg correlated with foraminal height (r=-0.45), foraminal surface (r=-0.36) and anterior (r=-0.41) and posterior disc height (r=-0.43). CONCLUSION: ALIF provided significant indirect foraminal decompression and improvement of radicular pain. The increase of foraminal height, surface, and posterior disc height is directly associated with radicular pain improvement. LEVEL OF EVIDENCE: IV AVAILABILITY OF DATA AND MATERIAL: The datasets used and/or analyzed in the present study are available from the corresponding author on reasonable request.

Anterior Lumbar Interbody Fusion (ALIF) L5-S1 with overpowering of posterior lumbosacral instrumentation and fusion mass: a reliable solution in revision spine surgery.

BACKGROUND AND PURPOSE: In cases of spine surgical revisions of patients affected by sagittal malalignment, the restoration of the ideal lumbar lordosis (LL) is mandatory. ALIF procedures represent a powerful and effective approach to improve the LL in case of hypolordosis. This study evaluates the feasibility of ALIF to overpower posterior lumbar instrumentation and fusion mass in revision spine surgery and secondarily to estimate complications, clinical and radiological outcomes. METHODS: This is a single-center retrospective analysis of prospectively collected data on the use of ALIF overpowering in cases of lumbosacral instrumentation and/or fusion. Demographic, comorbidity, corrective strategy adopted, surgical data, clinical and radiological results, and intraoperative and postoperative complications were recorded. RESULTS: Twelve patients (3 male; 9 female) underwent overpowering ALIF L5-S1 were included in the study with a mean FU of 34.0 ± 13.4 months. In 10 cases, a posterior titanium instrumentation and fusion mass were present; in 2 patients, only a fusion mass was present. Indicators of pain and disability improved in all patients (p < 0.01). Sagittal realignment with the restoration of ideal spinopelvic parameters was obtained in all cases. One peritoneal lesion requiring intraoperative suture without sequelae, two cases of postoperative radiculopathy, and one posterior wound infection requiring surgical debridement and antibiotic therapy were reported. CONCLUSIONS: Anterior implant of lordotic and hyperlordotic cages with increasing segmental lordosis is possible in the presence of posterior instrumentation and/or solid fusion mass. The biomechanical strength of this corrective technique can overcome posterior instrumentation and bone fusion resistance, therefore allowing a single-staged surgery for sagittal realignment.

Useful and innovative methods for the treatment of postoperative coronal malalignment in adult scoliosis: the "kickstand rod" and "tie rod" procedures.

STUDY DESIGN: Surgical technique description and case series. OBJECTIVE: To describe the use of two techniques for the correction of postoperative coronal imbalance after surgical treatment for adult spine deformity (ASD). Sagittal and coronal spinal malalignments are often present in patients with ASD or in patients who have undergone spine surgery. Surgical correction of coronal imbalance is insufficiently investigated, and the literature provides a limited spectrum of surgical options when compared to sagittal imbalance. Nevertheless, this deformity can compromise the surgical outcome and can increase the risk of hardware failure. METHODS: The kickstand (KR) and tie rod (TR) techniques utilize an accessory rod, linking the previous instrumentation to an independent iliac screw. After a proper release of the lumbar spine with anterior release or posterior osteotomies, the KR technique pushes with distraction on the concave side, whereas the TR technique pulls with compression on the convex side. Four patients (mean age, 64 years; SD 5.7) affected by severe postoperative coronal imbalance were treated. C7-PL ranges from 39 to 76 mm. The mean preoperative ODI was 70/100 (range from 55 to 82). All patients had previous spinopelvic fixation as a consequence of corrective surgery for adult spine deformity. The patients were surgically treated with the addition of supplementary rods connected to the ilium. The rods were used in the concavity or convexity of the deformity functioning as "kickstand" or "tie" or a combination of both. RESULTS: The mean surgical correction of C7-PL was 35 mm (range from 20 to 52 mm). In particular, the mean correction for kickstand rod technique was 26 mm and for tie rod technique was 43 mm. All of the patients improved their preoperative disability, and mean ODI was 30/100 (range from 10 to 60) at median 19-month follow-up. All postoperative imaging showed implants were in proper position without hardware failure. All of the patients treated demonstrated an immediate postoperative improvement in terms of coronal displacement of the spine. No complications were observed. At 1-year follow-up, all of the patients remained satisfactory in terms of clinical outcomes. CONCLUSION: The kickstand and tie rod techniques are effective in the treatment of postoperative coronal malalignment. Further studies are needed to confirm these findings. LEVEL OF EVIDENCE: V: Case report. These slides can be retrieved under Electronic Supplementary Material.

The problems associated with revision surgery.

This article highlights the issue related to revision surgery in spine and the possible implications in the next future. These slides can be retrieved under Electronic Supplementary Material.

Pedicle screw insertion with patient-specific 3D-printed guides based on low-dose CT scan is more accurate than free-hand technique in spine deformity patients: a prospective, randomized clinical trial.

BACKGROUND: Screw misplacement incidence can be as high as 15-30% in spine deformity surgery, with possible devastating consequences. Some technical solutions to prevent misplacement require expensive devices. MySpineTM comprises a low-dose CT scan of the patient's spine to build a virtual model of the spine to plan the screw trajectories and a 3D-printed patient-specific guide system to prepare the screw trajectories and to implant the screws in the vertebrae in order to increase reproducibility and safety of the implants. The aim of this open-label, single-center, prospective randomized clinical trial with independent evaluation of outcomes was to compare the accuracy of free-hand insertion of pedicle screws to MySpineTM 3D-printed patient-specific guides. METHODS: Twenty-nine patients undergoing surgical correction for spinal deformity were randomized to Group A (pedicle screws implantation with MySpineTM) or Group B (free-hand implantation). Group A received 297 pedicle screws, and Group B 243 screws. Forty-three screws in Group A crossed over to free-hand implantation. Screw position was graded according to Gertzbein in grades 0, A, B or C, with grades 0 or A considered as "safe area." Total fluoroscopy dose and time were compared in six patients of each group. RESULTS: Comparing the two study groups, we observed a statistically significant difference between the two groups (p < 0.05), with 96.1% of screws in the "safe area" in Group A versus a 82.9% in Group B. Group-A patients had a mean effective dose of 0.23 mSv compared to 0.82 mSv in Group B. Patient-specific, 3D-printed pedicle screw guides increase safety in a wide spectrum of deformity conditions. In addition, the total radiation dose is reduced, even considering the need of a low-dose preoperative CT for surgical planning. LEVEL OF EVIDENCE: I. These slides can be retrieved under Electronic Supplementary Material.

Focal disorders of the spine with compensatory deformities: how to define them.

PURPOSE: In this paper, the authors propose classifying the epiphenomenon of spinal deformity in two different categories: structural deformity, when the main driver of the observed deformity is a fixed and stiff alteration of the spinal segments, and compensatory deformity, which includes cases where the observed deformity is due to focal abnormalities. This last category comprises, but is not limited to, spinal stenosis, spondylolisthesis, disc herniation, infection or tumor, hip disease or neurological disease (such as Parkinson's disease). METHOD: Narrative review article. RESULTS: We analyzed the focal diseases of the spine that may cause a compensatory deformity inducing adaptation in the unaffected part of the spine. CONCLUSION: The compensatory mechanisms involved in adaptive deformity represent an attempt to maintain a global alignment, to escape from pain or to control body posture. These slides can be retrieved under Electronic Supplementary material.

Hypercomplex pedicle subtraction osteotomies: definition, early clinical and radiological results and complications.

PURPOSE: To describe hypercomplex pedicle subtraction osteotomies (HyC-PSO) for adult spine deformity with sagittal imbalance in terms of preoperative, intraoperative and postoperative outcomes and complications. METHODS: From a prospective single centre database, patients undergoing PSO between January 2016 and May 2017 were reviewed. HyC-PSO were defined as those in patients with one of the following conditions: sagittal correction > 45° needed at a single level or at 1-3 consecutive vertebrae, more than 60° of total sagittal correction needed and PSO on segments of the spine with congenital deformities. RESULTS: 22 patients were included, 14 had standard PSO (group A) and 8 had HyC-PSO (group B). Significant correction of lumbar lordosis (LL) and pelvic (PT) was noted in both groups (p < 0.01). Operative time was longer in HyC-PSO, 604 min compared to standard PSO, 478 min. A trend versus greater intraoperative blood loss (3837 vs 2285 ml) and greater intraoperative blood infusion (from cell saver plus homologous, 2306 vs 1280 ml) was recorded in HyC-PSO (ns). Patients in group B received significantly more blood units intra and postoperatively (8.25 vs 4.71 units, p = 0.006). Sagittal correction at the PSO level (54.7°-30° to 85°-vs 26.8°-8° to 39°-, p = 0.000) and total sagittal correction (64.5°-50 to 95°-vs 39.8°-20° to 51°-, p = 0.000) were greater in HyC-PSO. PROMs at the last available follow-up did not show significant differences between groups for any of the outcomes analyzed. Complications were similar in both groups. CONCLUSION: This is the first report on hypercomplex pedicle subtraction osteotomies. Hypercomplex PSO describes a subset of clinical scenarios with increased surgical effort that can be measured as longer surgical time and greater blood transfusion requirements. Successful correction of misalignment can be achieved in this specific group of patients, and clinical results and complications profile could be similar to standard PSO procedures.

Long fusions to S1 with or without pelvic fixation can induce relevant acute variations in pelvic incidence: a retrospective cohort study of adult spine deformity surgery.

PURPOSE: The purpose of this study is to verify if any changes occur in pelvic incidence (PI) in adult patients undergoing long fusion to sacrum for spine deformity and to describe the effect of fixation to pelvis on these variations. METHODS: We conducted a cross sectional study. Sixty-six adults patients, 87% females (mean ± SD age: 65.1 ± 7.6 years), undergoing fusion from the thoracic spine to the sacrum for adult spine deformity were included. Patients were divided in two different groups: Group A: sacral fixation alone and Group B: sacral fixation plus pelvis fixation. Pre and postoperative standardized full-standing X-rays were analyzed with measurement of: PI, pelvic tilt (PT), lumbar lordosis (LL) and sagittal vertical axis (SVA). RESULTS: A significant effect of time interaction (preoperative to early postoperative; F = 59.93, F = 44.78 and F = 39.87, all p < 0.001) existed for PT, SS and TK in both groups (all, p < 0.001). After adjustment for patients' age (>65 vs. <65 years), a statistically significant increase of PI was observed in patients >65 years (p = 0.006) in Group A between preoperative and postoperative measurements. All patients in Group B exhibited a decrease in PI from preoperative to postoperative. CONCLUSIONS: Older patients undergoing long fusion to the sacrum without pelvic fixation had an increase in PI after surgery. Conversely, pelvic fixation with hips intraoperatively extended has decreased the value of PI from pre- to early postoperative. These changes could be related to degeneration of the sacroiliac joints causing increased rotational mobility and the magnitude of the differences is in the range of clinical relevance.

Revisiting the Local Structure in Ge-Sb-Te based Chalcogenide Superlattices.

The technological success of phase-change materials in the field of data storage and functional systems stems from their distinctive electronic and structural peculiarities on the nanoscale. Recently, superlattice structures have been demonstrated to dramatically improve the optical and electrical performances of these chalcogenide based phase-change materials. In this perspective, unravelling the atomistic structure that originates the improvements in switching time and switching energy is paramount in order to design nanoscale structures with even enhanced functional properties. This study reveals a high- resolution atomistic insight of the [GeTe/Sb2Te3] interfacial structure by means of Extended X-Ray Absorption Fine Structure spectroscopy and Transmission Electron Microscopy. Based on our results we propose a consistent novel structure for this kind of chalcogenide superlattices.

Nano-scaled chalcogenide-based memories.

Today phase change memory (PCM) technology has reached product maturity at 90 and 65 nm nodes, while the 45 nm node is under development and is expected to enter in the market soon. The continuous decrease of the cell size with scaling leads to an effective active area as small as 150 nm(2) and an active volume involved in the phase transformation of about 10(4) nm(3), thus entering definitively into the nanotechnology world. At this extremely reduced dimension, the reliability of the device must be carefully investigated. In this work we show that the cycling performance of the device is well maintained, not being a problem for either the bipolar transistor or the storage element. The phase transition from the amorphous to the crystalline state is, of course, one of the most interesting phenomena, impacting cell retention capability and device performance. The stochastic nature of nano-nuclei percolation in the amorphous matrix is shown as an important ingredient in the retention of PCM devices. The related dispersion in crystallization times is analyzed through a crystallization Monte Carlo model and a physical insight into nucleation and growth mechanisms is provided.