Study Design.Heterogeneous data collection through a mix of prospective, retrospective, and ambispective methods. Objective.To evaluate the effect of biological sex on patient-reported outcomes after spinal fusion surgery for lumbar degenerative disease. Summary of Background Data.Current literature suggests sex differences regarding clinical outcome after spine surgery may exist. Substantial methodological heterogeneity and limited comparability of studies warrants further investigation of sex-related differences in treatment outcomes. Materials and Methods.We analyzed patients who underwent spinal fusion with or without pedicle screw insertion for lumbar degenerative disease included within a multinational study, comprising patients from 11 centers in seven countries. Absolute values and change scores (change from preoperative baseline to postoperative follow-up) for 12-month functional impairment [Oswestry disability index (ODI)] and back and leg pain severity [numeric rating scale (NRS)] were compared between male and female patients. Minimum clinically important difference (MCID) was defined as >30% improvement. Results.Six-hundred sixty (59%) of 1115 included patients were female. Female patients presented with significantly baseline ODI (51.5 +/- 17.2 vs. 47.8 +/- 17.9, P<0.001), back pain (6.96 +/- 2.32 vs. 6.60 +/- 2.30, P=0.010) and leg pain (6.49 +/- 2.76 vs. 6.01 +/- 2.76, P=0.005). At 12 months, female patients still reported significantly higher ODI (22.76 +/- 16.97 vs. 20.50 +/- 16.10, P=0.025), but not higher back (3.13 +/- 2.38 vs. 3.00 +/- 2.40, P=0.355) or leg pain (2.62 +/- 2.55 vs. 2.34 +/- 2.43, P=0.060). Change scores at 12 months did not differ significantly among male and female patients in ODI (triangle 1.31, 95% CI: -3.88 to 1.25, P=0.315), back (triangle 0.22, 95% CI: -0.57 to 0.12, P=0.197), and leg pain (triangle 0.16, 95% CI: -0.56 to 0.24, P=0.439). MCID at 12 months was achieved in 330 (77.5%) male patients and 481 (76.3%) female patients (P=0.729) for ODI. Conclusion.Both sexes experienced a similar benefit from surgery in terms of relative improvement in scores for functional impairment and pain. Although female patients reported a higher degree of functional impairment and pain preoperatively, at 12 months only their average scores for functional impairment remained higher than those for their male counterparts, while absolute pain scores were similar for female and male patients.

Objectives: To determine whether a closed dressing protocol reduces the surgical site infections (SSI) rate compared to conventional closing techniques. Methods: Patients who underwent lumbar spine surgery at two neurosurgical centers were retrospectively included from June 2015 to December 2019. Data on patients, general risk factors, and surgical risk factors for SSI were collected. Patients were subdivided into two groups: a Closed Protocol where the Dermabond® ± Prineo® dressing system was used, and a Conventional Protocol, namely sutures or staples. Statistical analysis was undertaken to compare the infection rates among the different closure techniques. Results: Altogether, 672 patients were included. In the whole cohort, 157 (23.36%) underwent skin closure with staples, 122 (18.15%) with sutures, 98 (14.58%) with intracutaneous sutures, 78 (11.61%) with Dermabond®, and 217 (32.29%) with Demabond® + Prineo®. The overall infection rate was 2.23% (n = 15). Skin suture had the highest infection rate (4.10%), while the lowest was Dermabond® (1.28%) and Dermabond® + Prineo® (1.4%), though the difference was not significant. Risk factors for SSI included higher BMI (29.46 kg/m2 vs. 26.96 kg/m2, p = 0.044), other sites infection (20.00% vs. 2.38%, p = 0.004), and a higher national nosocomial infections surveillance score (p = 0.003). Conclusions: This study showed that a closed protocol with the use of adhesive dressing with or without mesh had a slight tendency to lower infection rates compared to conventional protocol with sutures or staples, although no statistically significant difference was found between the closure techniques. Larger randomized studies are needed to investigate this potential benefit avoiding selection bias.

Study design: Heterogeneous data collection via a mix of prospective, retrospective, and ambispective methods. Objective: To evaluate the effect of biological sex on patient-reported outcomes after spinal fusion surgery for lumbar degenerative disease. Summary of Background Data: Current literature suggests sex differences regarding clinical outcome after spine surgery may exist. Substantial methodological heterogeneity and limited comparability of studies warrants further investigation of sex-related differences in treatment outcomes. Methods: We analyzed patients who underwent spinal fusion with or without pedicle screw insertion for lumbar degenerative disease included within a multinational study, comprising patients from 11 centers in 7 countries. Absolute values and change scores (change from pe-operative baseline to post-operative follow-up) for 12-month functional impairment (Oswestry disability index [ODI]) and back and leg pain severity (numeric rating scale [NRS]) were compared between male and female patients. Minimum clinically important difference (MCID) was defined as > 30% improvement. Results: Six-hundred-sixty (59%) of 1115 included patients were female. Female patients presented with significantly baseline ODI (51.5 ± 17.2 vs. 47.8 ± 17.9, P<0.001) and back pain (6.96 ± 2.32 vs. 6.60 ± 2.30, P=0.010) and leg pain (6.49 ± 2.76 vs. 6.01 ± 2.76, P=0.005). At 12-months, female patients still reported significantly higher ODI (22.76 ± 16.97 vs. 20.50 ± 16.10, P=0.025), but not higher back (3.13 ± 2.38 vs. 3.00 ± 2.40, P=0.355) or leg pain (2.62 ± 2.55 vs. .34 ± 2.43, P=0.060). Change scores at 12 months did not differ significantly among male and female patients in ODI (∆ 1.31, 95% CI -3.88-1.25, P=0.315), back (∆ 0.22, 95% CI -0.57-0.12, P=0.197) and leg pain (∆ 0.16, 95% CI -0.56-0.24, P=0.439). MCID at 12-months was achieved in 330 (77.5%) male patients and 481 (76.3%) female patients (P=0.729) for ODI. Conclusion: Both sexes experienced a similar benefit from surgery in terms of relative improvement in scores for functional impairment and pain. Although female patients reported a higher degree of functional impairment and pain preoperatively, at 12 months only their average scores for functional impairment remained higher than those for their male counterparts, while absolute pain scores were similar for female and male patients.

Purpose Pedicle subtraction osteotomy (PSO) as an invasive procedure with high reoperation and complication rates in an often elderly population has often been questioned. The purpose of our study was to evaluate the impact of PSO for sagittal imbalance (SI) on patient-reported outcomes including self-reported satisfaction and health-related quality of life 2 years postoperatively. Methods Consecutive patients who underwent correction of their spinal deformity by thoracolumbar PSO were assessed using self-reporting questionnaires 2 years postoperatively. Outcome was measured by visual analogue scale (VAS) for back and leg pain, Oswestry Disability Index (ODI), and EQ-5D scores. Additionally, a Patient Satisfaction Index (PSI) rated in four grades (A: very satisfied to D: not satisfied), walking range, and the Timed Up and Go (TUG) Test were evaluated. Results Sixty-five patients were included, and each parameter was assessed preoperatively and 24 months postoperatively. The intervention led to significant improvements in back pain (8.1 ± 1.2 vs. 2.9 ± 1.9; p < 0.001), as well as ODI scores (57.7 ± 13.9 vs. 32.6 ± 18.9; p < 0.001), walking range (589 ± 1676 m vs. 3265 ± 3405 m; p < 0.001), and TUG (19.2 s vs. 9.7 s; p < 0.05). 90.7% of patients ( n = 59/65) reported a PSI grade “A” or “B” 24 months postoperatively. Conclusion Patient satisfaction 24 months after PSO for SI is high. Quality of life improved significantly by restoring sagittal balance.

Background Indications and outcomes in lumbar spinal fusion for degenerative disease are notoriously heterogenous. Selected subsets of patients show remarkable benefit. However, their objective identification is often difficult. Decision-making may be improved with reliable prediction of long-term outcomes for each individual patient, improving patient selection and avoiding ineffective procedures. Methods Clinical prediction models for long-term functional impairment [Oswestry Disability Index (ODI) or Core Outcome Measures Index (COMI)], back pain, and leg pain after lumbar fusion for degenerative disease were developed. Achievement of the minimum clinically important difference at 12 months postoperatively was defined as a reduction from baseline of at least 15 points for ODI, 2.2 points for COMI, or 2 points for pain severity. Results Models were developed and integrated into a web-app ( https://neurosurgery.shinyapps.io/fuseml/ ) based on a multinational cohort [ N = 817; 42.7% male; mean (SD) age: 61.19 (12.36) years]. At external validation [ N = 298; 35.6% male; mean (SD) age: 59.73 (12.64) years], areas under the curves for functional impairment [0.67, 95% confidence interval (CI): 0.59–0.74], back pain (0.72, 95%CI: 0.64–0.79), and leg pain (0.64, 95%CI: 0.54–0.73) demonstrated moderate ability to identify patients who are likely to benefit from surgery. Models demonstrated fair calibration of the predicted probabilities. Conclusions Outcomes after lumbar spinal fusion for degenerative disease remain difficult to predict. Although assistive clinical prediction models can help in quantifying potential benefits of surgery and the externally validated FUSE-ML tool may aid in individualized risk–benefit estimation, truly impacting clinical practice in the era of “personalized medicine” necessitates more robust tools in this patient population.

Sensorimotor function of patients with spinal cord injury (SCI) is commonly assessed according to the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI). From the ISNCSCI segmental motor and sensory assessments, upper and lower extremity motor scores (UEMS and LEMS), sum scores of pinprick (PP) and light touch (LT) sensation, the neurological level of injury (NLI) and the classification of lesion severity according to the American Spinal Injury Association Impairment Scale (AIS) grade are derived. Changes of these parameters over time are used widely to evaluate neurological recovery. Evaluating recovery based on a single ISNCSCI scoring or classification variable, however, may misestimate overall recovery. Here, we propose an Integrated Neurological Change Score (INCS) based on the combination of normalized changes between two time points of UEMS, LEMS, and total PP and LT scores. To assess the agreement of INCS with clinical judgment of meaningfulness of neurological changes, changes of ISNCSCI variables between two time points of 88 patients from an independent cohort were rated by 20 clinical experts according to a five-categories Likert Scale. As for individual ISNCSCI variables, neurological change measured by INCS is associated with severity (AIS grade), age, and time since injury, but INCS better reflects clinical judgment about meaningfulness of neurological changes than individual ISNCSCI variables. In addition, INCS is related to changes in functional independence measured by the Spinal Cord Independence Measure (SCIM) in patients with tetraplegia. The INCS may be a useful measure of overall neurological change in clinical studies.

Three-column osteotomy (3-CO) is a powerful technique in adult deformity surgery, and pedicle subtraction osteotomy (PSO) is the workhorse to correct severe kyphotic spinal deformities. Aging of the population, increasing cases of iatrogenic flat back deformities and understanding the importance of sagittal balance have led to a dramatic increase of this surgical technique. Surgery, however, is demanding and associated with high complication rates so that every step of the procedure requires meticulous technique. Particularly, osteotomy closure is associated with risks like secondary fracture, translation, or iatrogenic stenosis. This step is traditionally performed by compression or a cantilever maneuver with sometimes excessive forces on the screws or instrumentation. Implant loosening or abrupt subluxation resulting in construct failure and/or neurological deficits can result. The aim of this prospective registry study was to assess the efficacy and safety of our surgical PSO technique as well as the osteotomy closure by flexing a hinge-powered OR table. In a series of 84 consecutive lumbosacral 3-CO, a standardized surgical technique with special focus on closure of the osteotomy was prospectively evaluated. The surgical steps with the patients positioned prone on a soft frame are detailed. Osteotomy closure was achieved by remote controlled bending of a standard OR table without compressive or cantilever forces in all 84 cases. This technique carries a number of advantages, particularly the reversibility and the slow speed of closure with minimum force. There was not a single mechanical intraoperative complication such as vertebral body fracture, subluxation, or adjacent implant loosening during osteotomy closure, compared to external cohorts using the cantilever technique (p = 0.130). The feasibility of controlled 3-CO closure by flexing a standard OR table is demonstrated. This technique enables a safe, gentle closure of the osteotomy site with minimal risk of implant failure or accidental neurological injury.

Monostotic fibrous dysplasia (MFD) of the lumbar spine represents an exceedingly rare lesion. A 26-year-old patient presented with a progressive osteolytic lesion of the vertebral body L2 and the diagnosis of MFD. A minimally invasive left-sided eXtreme Lateral Interbody Fusion (XLIF) approach with resection of the vertebral body L2 with placement of a mesh cage was performed. No complications were observed perioperatively and the symptoms rapidly improved. Minimally invasive piecemeal resection with a combined dorsolateral approach showed a favorable clinical and radiological outcome and seems to be a safe and reliable technique for MFD.

Background Patients with intervertebral disc herniation undergo surgical removal of herniated disc material in cases of persisting symptoms and/or neurologic deficits. While motor deficits often prompt surgery, little is known about the optimal timing of surgery in these cases. The aim of this study was to prospectively evaluate the impact of timing of disc surgery on motor recovery. Does postponing surgical treatment worsen outcome? Method In total, 120 patients with sciatica and/or sensorimotor deficits due to a lumbar disc herniation were surgically treated at the authors’ center within a 3-month period. In 60 patients, motor deficits were present at the time of admission. Motor function was assessed using manual muscle testing and subdivided according to the Medical Research Council (MRC) scale. Patient demographics, neurologic deficits, duration of motor deficits, treatment characteristics, and outcome were assessed. At a minimum follow-up of 1 year, functional recovery and complications were collated. Patients were subdivided into groups according to the severity of the paresis (MRC ≤ 3/5 vs. MRC 4/5). Intra-group differences were compared based on the duration of the neurologic deficits. Results Patients with moderate and severe paresis (MRC ≤ 3/5) benefit from treatment within 72 h as they were shown to have a significantly higher complete recovery rate at 1-year follow-up (75% vs. 0%; p < 0.001). Conclusion Immediate surgery should be offered to patients with moderate and severe motor deficits to increase the likelihood of neurologic recovery. This prospective data may have an impact on emergency triage in these patients.

BACKGROUND:The desire to improve accuracy and safety and to favor minimally invasive techniques has given rise to spinal robotic surgery, which has seen a steady increase in utilization in the past 2 decades. However, spinal surgery encompasses a large spectrum of operative techniques, and robotic surgery currently remains confined to assistance with the trajectory of pedicle screw insertion, which has been shown to be accurate and safe based on class II and III evidence. The role of robotics in improving surgical outcomes in spinal pathologies is less clear, however.METHODS:This comprehensive review of the literature addresses the role of robotics in surgical outcomes in spinal pathologies with a focus on the various meta-analysis and prospective randomized trials published within the past 10 years in the field.RESULTS:It appears that robotic spinal surgery might be useful for increasing accuracy and safety in spinal instrumentation and allows for a reduction in surgical time and radiation exposure for the patient, medical staff, and operator.CONCLUSION:Robotic assisted surgery may thus open the door to minimally invasive surgery with greater security and confidence. In addition, the use of robotics facilitates tireless repeated movements with higher precision compared with humans. Nevertheless, it is clear that further studies are now necessary to demonstrate the role of this modern tool in cost-effectiveness and in improving clinical outcomes, such as reoperation rates for screw malpositioning.

Introduction Robotic guidance (RG) and computer-assisted navigation (NV) have seen increased adoption in instrumented spine surgery over the last decade. Although there exists some evidence that these techniques increase radiological pedicle screw accuracy compared with conventional freehand (FH) surgery, this may not directly translate to any tangible clinical benefits, especially considering the relatively high inherent costs. As a non-randomised, expertise-based study, the European Robotic Spinal Instrumentation Study aims to create prospective multicentre evidence on the potential comparative clinical benefits of RG, NV and FH in a real-world setting.Methods and analysis Patients are allocated in a non-randomised, non-blinded fashion to the RG, NV or FH arms. Adult patients that are to undergo thoracolumbar pedicle screw instrumentation for degenerative pathologies, infections, vertebral tumours or fractures are considered for inclusion. Deformity correction and surgery at more than five levels represent exclusion criteria. Follow-up takes place at 6 weeks, as well as 12 and 24 months. The primary endpoint is defined as the time to revision surgery for a malpositioned or loosened pedicle screw within the first postoperative year. Secondary endpoints include patient-reported back and leg pain, as well as Oswestry Disability Index and EuroQOL 5-dimension questionnaires. Use of analgesic medication and work status are recorded. The primary analysis, conducted on the 12-month data, is carried out according to the intention-to-treat principle. The primary endpoint is analysed using crude and adjusted Cox proportional hazards models. Patient-reported outcomes are analysed using baseline-adjusted linear mixed models. The study is monitored according to a prespecified monitoring plan.Ethics and dissemination The study protocol is approved by the appropriate national and local authorities. Written informed consent is obtained from all participants. The final results will be published in an international peer-reviewed journal.Trial registration number Clinical Trials.gov registry NCT03398915; Pre-results, recruiting stage.

Thoracic myelopathy is often caused by vertebral body fractures resulting from neoplastic conditions, traumatic events, or infectious diseases. One of the preferred procedures for treating it is the lateral extracavitary approach (LECA) with single-level or multilevel decompressive corpectomy and reconstruction. The aim of this retrospective study was to analyze the thoracic lateral extracavitary approach with corpectomy using vertebral body replacement systems (VBR-S) and dorsal reconstruction. Twenty-four patients with metastatic or primary lesions of thoracic vertebrae T2–T12 underwent spinal decompression and ventral column reconstruction with correction of spinal deformity via a LECA. One-level to four-level corpectomies were performed with additional navigated dorsal pedicle screw fixation at an average of two levels above and below the corpectomy lesion. None of the patients received preoperative spinal embolization, and the majority of the patients were admitted to radiotherapy postoperatively. Their mean age was 56 years (± 15), with a female-to-male sex ratio of 8 to 16. Patients with a minimum follow-up period of 16 months were included. The Karnofsky index, preoperative and postoperative numeric rating scale (NRS), and Frankel scale were measured. In addition, intraoperative loss of blood (LOB), units of packed red blood cell (PRBC) transfusions, the duration of the operation, and the hospitalization period were evaluated and correlated with preoperative and postoperative values. The majority of the patients were suffering from metastatic lesions and were treated with a 1 level corpectomy (median 1 level, range 1 to 4). The mean duration of surgery was 288 min (± 121) and the mean LOB was 1626 mL (± 1486 mL), with approximately two PRBC units per patient used. All patients were transferred to the intensive care unit (ICU) postoperatively, with a mean ICU stay of 2.0 days (± 1 day). The mean hospitalization period was 13 days (± 7 days). No implant-related failures or procedure-related deaths were observed. Significant differences were noted between the preoperative and postoperative Karnofsky index (74 vs. 84%) and NRS (4 vs. 2). One patient required revision surgery due to a superficial wound infection, and another needed revision surgery due to a dural tear. In another patient, an iatrogenic dural tear was repaired during the same surgical procedure and did not lead to postoperative complications. Four pleural effusions and one pneumothorax were observed, so that the overall complication rate was approximately 33%. Four of the patients died within 2 years of the operation due to progression of the primary disease. Lateral corpectomy and sagittal reconstruction of the thoracic spine using VBR-S conducted via a navigated LECA approach yields favorable results, despite the burden of neoplastic disease. These challenging procedures are accompanied by increased LOB and hospitalization periods, with moderate transfusion requirements. Surgery-related complications are low and local tumor control is satisfactory, despite the progression of the underlying neoplastic disease. However, optimal surgical therapy does not ensure long-term survival.

Surgical correction of fixed thoracolumbar deformity is usually achieved by estimating the preoperatively planned correction angles during surgery and is therefore prone to inaccuracy. This is particularly problematic in biplanar deformities. To overcome these difficulties, 3D model for planning, preparation, and simulation of an asymmetric pedicle subtraction osteotomy (aPSO) was printed and used to realign coronal and sagittal balance in case of rigid degenerative kyphoscoliosis. A 59-year-old woman presented with severe back pain and spinal claudication and was diagnosed with a rigid kyphoscoliosis with multilevel spinal stenosis. Spino-pelvic parameters were measured preoperatively (pelvic incidence 47° [PI], lumbar lordosis 18° [LL]; pelvic tilt 42° [PT], T1 pelvic angle 40° [TPA], Cobb angle 33°, sagittal vertical axis 10.5 cm [SVA]). To aid the complex deformity in the sagittal and coronal plane, a 1:1 3D model of the spine was printed according to the preoperative computed tomography (CT). With the use of a rebalancing software, the spine was prepared in vitro as a model for intraoperative realignment and the correction was preoperatively simulated. Surgery was accomplished according to the preoperative software-guided plan. Asymmetric pedicle subtraction osteotomy (aPSO) of L3 identical to the 3D model was performed. Additionally, a Smith-Peterson osteotomy of L4/5 with transforaminal lumbar interbody fusion (TLIF) and laminectomy of L2–S1 with pedicle screw instrumentation TH12–S1 was accomplished. Postoperative radiological parameters revealed good success (LL 40°, SVA 6 cm, PT 19°, TPA 22°, and a Cobb angle of 8°). Improvement of the Oswestry disability index (ODI) of 42 to 18, the visual analog scale (VAS) of 8 to 1, and walking distance 100 to 8000 m compared to preoperatively resulted at 24 months follow-up. The precise coronal and sagittal correction of a rigid degenerative kyphoscoliosis presents a major challenge. Asymmetric PSO is able to realign the thoracolumbar spine in both the coronal and sagittal planes. The creation of an in vitro 3D-printed model of a patient’s spinal deformity in combination with a software to calculate the correction angles facilitates preoperative planning and implementation of aPSO.

Cell-based regenerative approaches have been suggested as primary or adjuvant procedures for the treatment of degenerated intervertebral disc (IVD) diseases. Our aim was to evaluate the regenerative and immunogenic properties of mildly and severely degenerated cervical nucleus pulposus (NP) cells with regard to cell isolation, proliferation and differentiation, as well as to cell surface markers and co-cultures with autologous or allogeneic peripheral blood mononuclear cells (PBMC) including changes in their immunogenic properties after 3-dimensional (3D)-culture. Tissue from the NP compartment of 10 patients with mild or severe grades of IVD degeneration was collected. Cells were isolated, expanded with and without basic fibroblast growth factor and cultured in 3D fibrin/poly (lactic-co-glycolic) acid transplants for 21 days. Real-time reverse-transcription polymerase chain reaction (RT-PCR) showed the expression of characteristic NP markers ACAN, COL1A1 and COL2A1 in 2D- and 3D-culture with degeneration- and culture-dependent differences. In a 5,6-carboxyfluorescein diacetate N-succinimidyl ester-based proliferation assay, NP cells in monolayer, regardless of their grade of degeneration, did not provoke a significant proliferation response in T cells, natural killer (NK) cells or B cells, not only with donor PBMC, but also with allogeneic PBMC. In conjunction with low inflammatory cytokine expression, analyzed by Cytometric Bead Array and fluorescence-activated cell sorting (FACS), a low immunogenicity can be assumed, facilitating possible therapeutic approaches. In 3D-culture, however, we found elevated immune cell proliferation levels, and there was a general trend to higher responses for NP cells from severely degenerated IVD tissue. This emphasizes the importance of considering the specific immunological alterations when including biomaterials in a therapeutic concept. The overall expression of Fas receptor, found on cultured NP cells, could have disadvantageous implications on their potential therapeutic applications because they could be the targets of cytotoxic T-cell activity acting by Fas ligand-induced apoptosis.