Search Results (57)

Background/Objectives: Minimally invasive spine surgery (MISS) is complex and requires proficiency with a variety of technological and robotic modalities. Acquiring these skills is a long and involved process, often with a steep learning curve. This paper seeks to characterize the state of MISS training in neurosurgical and orthopedic residency programs, focusing on their effectiveness at minimizing substantial learning curves in the field, as well as highlighting potential areas for future growth. Methods: We conducted a scoping review of the PubMed, Scopus, and Embase databases utilizing the PRISMA extension for scoping reviews. Results: Of the 100 studies initially identified, 16 were included in our final analysis. MISS training types could be broadly grouped into four categories: virtual simulation (including AR and VR), physical models, hybrid didactic and simulation, and mentored training. Training with these modalities led to improvements in resident performance across multiple different MISS techniques, including percutaneous pedicle screw fixation, MIS dural repair, MIS-TLIF, MIS-LLIF, MIS-ULBD, microscopic discectomy/disk herniation repair, percutaneous needle placement, and surgical navigation. Specific improvements included reduced error rate, operation time, and fluoroscopy exposure, as well as increased procedural knowledge, accuracy, and confidence. Conclusions: The incorporation of MISS training modalities in spine surgery residency leads to increases in simulated performance and could serve as a means of overcoming significant learning curves in the field. Full article

Background: We aimed to analyze radiographic sagittal balance parameters in patients who underwent a TLIF procedure for single-level degenerative spondylolisthesis with a mean follow-up of 8.6 years and to determine whether lumbar lordosis affects long-term clinical outcomes. Methods: This prospective study included 32 patients who underwent single-level TLIF surgery for degenerative spondylolisthesis. Radiographic analysis of sagittal balance parameters and clinical examination including Oswestry Disability Index (ODI) scores were performed preoperatively, postoperatively, and at the last follow-up. A minimal clinically important difference threshold of 30% was accepted as clinically relevant. Results: Mean postoperative lumbar lordosis (LL) and segmental lordosis (SL) failed to improve postoperatively; nevertheless significant improvements in short- and long-term postoperative ODI scores were demonstrated (p < 0.001). Thoracic kyphosis (TK) and global sagittal balance parameters shifted anteriorly after 8.6 years (p < 0.001), but this increase did not affect clinical outcomes. Conclusions: Adequate decompression and solid bone fusion are foremost required to achieve improved long-term clinical outcomes in single-level TLIF procedures. In our studied cohort, failure to improve lordosis did not impair clinical outcomes postoperatively. With aging, thoracic kyphosis and anterior malalignment increase, and after 8.6 years, clinical improvements are starting to become insignificant. Full article

Background: Transforaminal lumbar interbody fusion (TLIF) with static cages is a frequently performed procedure. Larger series focusing on the use of expandable TLIF spacers are less common. Methods: This retrospective, single-center observational cohort study reviewed consecutive patients treated by TLIF using expandable titanium interbody implants (ALTERA™, Globus Medical Inc., Audubon, PA, USA) for degenerative pathologies from L2-S1 between 11/2018 and 09/2023. Surgical parameters, adverse events, radiological outcomes (fusion rate, segmental lordosis, spinopelvic parameters), and clinical outcomes were analyzed through a mean postoperative follow-up of 12 months. Results: This study identified 270 patients (mean age 65 years, 50.4% female) who underwent TLIF with expandable interbody spacers at 324 levels. Clinical outcomes were good or excellent in 74.1% of patients at 3 months and 71.8% at 12 months. Radiographic fusion was achieved in 73.1% of assessable segments at 12 months. Segmental lordosis increased significantly from 17.8° preoperatively to 20.0° at 12 months (p < 0.001). Adverse event (AE) rates were acceptable across all timepoints, with no device failures or device-associated complications observed. Conclusions: This study demonstrates that TLIF with expandable titanium interbody implants was safe, associated with high fusion rates, and enabled significant restoration of segmental lordosis that was maintained during follow-up. Full article

Objective: This study aimed to compare the clinical and radiological outcomes of dynamic rod stabilization with and without transforaminal lumbar interbody fusion (TLIF) in patients undergoing surgery for degenerative lumbar instability. Specifically, we evaluated the prognostic value of hybrid systems in reducing adjacent segment disease (ASD), enhancing fusion rates, and improving functional outcomes. Methods: A retrospective analysis was conducted on 62 patients treated between 2019 and 2022. Group 1 (n = 34) underwent dynamic rod stabilization alone, while Group 2 (n = 28) received dynamic stabilization combined with TLIF. Radiological assessments included disk height index (DHI) and fusion rates. Clinical outcomes were measured using the Visual Analog Scale (VAS) for back and leg pain at baseline, 12, and 24 months. Statistical analysis was performed using Jamovi^® software (version 2.4.1). Results: The hybrid group (dynamic + TLIF) demonstrated significantly higher anterior fusion rates (p < 0.001) and greater improvement in VAS scores for back (p = 0.005) and leg pain (p < 0.001) at 12 months. Although operative time was longer (p = 0.002), there was no significant difference in hospital stay (p = 0.635). No significant differences were observed in ASD development (p = 0.11) or pseudoarthrosis (p = 0.396). The hybrid group maintained better lumbar lordosis and higher adjacent segment DHI. Conclusions: Hybrid dynamic stabilization combined with TLIF provides superior clinical outcomes and fusion rates compared to dynamic stabilization alone, without significantly increasing the risk of ASD. These findings support the use of hybrid constructs as a balanced strategy for treating degenerative lumbar instability. Full article

Background: Structured titanium (ST) cages are designed to enhance osseointegration and fusion in lumbar interbody procedures. However, clinical and radiological outcomes following TLIF using ST cages—particularly with or without adjacent-level dynamic stabilization (DSS)—have not been widely reported. Objective: To evaluate 12-month fusion outcomes and patient-reported outcomes (PROMs) after TLIF with structured titanium cages, comparing cases with and without adjacent-level DSS. Methods: In this retrospective cohort study, 82 patients undergoing TLIF with ST cages were analyzed—41 with hybrid instrumentation (TLIF + DSS) and 41 with TLIF alone. PROMs (ODI, VAS for back and leg pain, EQ-5D-5L) were assessed preoperatively and at 12 months. Fusion was assessed via CT scans at 12 months. Results: PROMs significantly improved over time in both groups (p < 0.001 for ODI, VAS back, VAS leg), but there were no significant differences between the hybrid and non-hybrid groups. Overall, the interbody fusion rate was 84%. Complete fusion was observed in 84% of the hybrid group and 80% of the TLIF-only group (p = 0.716), with very low rates of non-union. Conclusions: Structured titanium cages demonstrated excellent 1-year fusion rates and supported significant clinical improvement after TLIF. The addition of dynamic stabilization had no measurable effect on patient-reported or radiological outcomes at 12 months. Long-term studies are needed to assess any potential effect of DSS on adjacent segment disease. Full article

The traditional bilateral pedicle screw system has been used for the treatment of various lumbar spine conditions including advanced degenerative disc disease. However, there is an ongoing need to develop more effective and less invasive techniques. The purpose of this study was to compare the traditional bilateral pedicle screw system (BPSS) with the novel reverse transdiscal screw system (RTSS) for lumbar disc degenerative disease. A 3D solid lumbar L1–L5 spine model was developed and validated based on a human CT scan. Fusions were simulated at L3–L4. The first scenario comprised a transforaminal lumbar interbody cage in combination with the bilateral pedicle screw-rod system (BPSS-TLIF). In the second scenario, the same TLIF cage was combined with reverse L3–L4 transdiscal screws (RTSS-TLIF). Testing parameters included range of motion (ROM) in three orthogonal axes, hardware (cage and screw) stress, and shear load resistance. The ROM of the surgical model was reduced by approximately 90% compared to the intact model at the fused level. The RTSS model demonstrated less ROM compared to the BPSS model at the fused level for all loading conditions. Overall, the RTSS model exhibited lower stress on both screws and cage compared with the BPSS model in all biomechanical testing conditions. The RTSS model also exhibited higher anterior and posterior shear load resistance than the BPSS model. In conclusion, the RTSS model proved superior to the BPSS model in all respects. These findings indicate that the RTSS could serve as a feasible option for patients undergoing lumbar fusion, especially for adjacent segment disease, potentially enhancing surgical outcomes for disc degeneration. Full article

Transforaminal lumbar interbody fusion (TLIF) is a commonly employed surgical technique for managing lumbar degenerative disease and spinal instability. While it offers advantages over posterior lumbar interbody fusion (PLIF), traditional TLIF often involves prolonged recovery and morbidity due to muscle retraction. To improve outcomes, several alternative techniques have emerged, including minimally invasive TLIF (MIS-TLIF), trans-Kambin percutaneous TLIF (PE-TLIF), and transfacet TLIF (TF-TLIF). Each approach presents distinct anatomical and technical advantages, yet no standardized framework exists to guide their selection based on individual patient anatomy. In this study, we review the evolution of TLIF techniques and propose a novel algorithm that integrates patient-specific imaging, anatomical variability, and segmentation data to guide surgical decision-making. By analyzing the surgical corridors, indications, and limitations of each approach, and presenting representative clinical cases, we demonstrate how this algorithm can be applied in practice. For instance, TF-TLIF may be optimal in patients requiring direct decompression without major deformity, while PE-TLIF may be appropriate for those with Kambin’s triangles measuring ≥ 9 mm, allowing for indirect decompression. This tailored framework aims to optimize outcomes and reduce complications. Further prospective validation and incorporation of AI-driven segmentation tools are needed to support broader clinical implementation. Full article

Background/Objectives: Degenerative lumbar spine disease (DLSD) is increasingly managed with minimally invasive surgery (MIS) and evolving anesthesia methods. While general anesthesia (GA) remains standard, spinal anesthesia (SA) may offer faster recovery and fewer side effects. This study compares the clinical and economic outcomes of GA versus SA in transforaminal lumbar interbody fusion (TLIF). Methods: A retrospective review of 18 TLIF patients (2018–2022) was performed, with 9 patients in each cohort. Patients were matched by demographics and procedure type. Data collected included operative time, blood loss, complications, postoperative opioid utilization, and 30-day readmissions. Costs were analyzed in categories: anesthesia, implants, inpatient care, operating room (OR) supplies, OR time, and PACU fees, using Wilcoxon Rank T-tests and Pearson Chi-Squared tests. Results: Clinical outcomes such as blood loss, and operative time were similar between groups. However, SA patients had significantly shorter LOS compared to GA (SA: 12 h vs. GA: 84 h, % difference: −150%, p = 0.04). Additionally, SA patients had lower total direct costs ($27,881.85 vs. $35,669.01; p = 0.027). Significant cost reductions with SA were noted in OR supplies/medications ($7367.93 vs. $10,879.46; p = 0.039) and inpatient costs ($621.65 vs. $3092.66; p = 0.027). Within these categories, reductions were observed for intravenous solutions, sedatives/anesthetics, pressure management, labs, imaging, evaluations, hospital care, and medications. Although costs for implants, anesthesia care, OR time, and PACU fees were lower with SA, these differences did not reach statistical significance. Conclusions: In TLIF for DLSD, SA provides significant economic advantages over GA while yielding comparable clinical outcomes. These results support SA as a cost-effective alternative, warranting further prospective studies to confirm these findings. Full article

Background/Objectives: Lumbar spine surgery has undergone significant technological transformation in recent years, driven by the goals of minimizing invasiveness, improving precision, and enhancing clinical outcomes. Emerging tools—including robotics, augmented reality, computer-assisted navigation, and artificial intelligence—have complemented the evolution of minimally invasive surgical (MIS) approaches, such as endoscopic and lateral interbody fusions. Methods: This systematic review evaluates the literature from February 2020 to February 2025 on technological and procedural innovations in LSS. Eligible studies focused on degenerative lumbar pathologies, advanced surgical technologies, and reported clinical or perioperative outcomes. Randomized controlled trials, comparative studies, meta-analyses, and large case series were included. Results: A total of 32 studies met the inclusion criteria. Robotic-assisted surgery demonstrated high accuracy in pedicle screw placement (~92–94%) and reduced intraoperative blood loss and radiation exposure, although long-term clinical outcomes were comparable to conventional techniques. Intraoperative navigation improved instrumentation precision, while AR enhanced ergonomic workflow and reduced surgeon distraction. AI tools showed promise in surgical planning, guidance, and outcome prediction but lacked definitive evidence of clinical superiority. MIS techniques—including endoscopic discectomy and MIS-TLIF—offered reduced blood loss, shorter hospital stays, and faster recovery, with equivalent pain relief, fusion rates, and complication profiles compared to open procedures. Lateral and oblique approaches (XLIF/OLIF) further optimized alignment and indirect decompression, with favorable perioperative metrics. Conclusions: Recent innovations in lumbar spine surgery have enhanced technical precision and perioperative efficiency without compromising patient outcomes. While short-term benefits are clear, long-term clinical advantages and cost-effectiveness require further investigation. Integration of robotics, navigation, AI, and MIS into spine surgery reflects an ongoing shift toward personalized, data-driven, and less invasive care. Full article

(1) Cage subsidence in spine surgery is a frequent clinical challenge. This study aimed to assess a novel screw augmentation technique for Transforaminal Lumbar Interbody Fusion in cadavers of reduced bone mineral density (BMD). (2) Forty human lumbar vertebrae (BMD 84.2 ± 24.4 mgHA/cm³, range 51–119 mgHA/cm³) were assigned to two groups: augmenting screw group and control group. The augmentation technique comprised placement of two additional subcortical screws. Ten constructs per group were loaded with a quasi-static load-to-failure protocol and other ten were cyclically loaded. Failure modes were documented. (3) During the quasi-static load-to-failure testing, the augmenting screw technique showed a significantly higher failure load (1426.0 ± 863.6 N) versus the conventional technique in the control group (682.2 ± 174.5 N, p = 0.032). Cyclic loading revealed higher number of cycles and corresponding load until reaching 5 mm subsidence and significantly higher number of cycles and corresponding load until reaching 10 mm subsidence for the augmenting screw technique (9645 ± 3050; 1164.5 ± 305.0 N) versus the conventional technique in the control group (5395 ± 2340; 739.5 ± 234.0 N, p < 0.05). Failure modes were different and showed bending of the augmenting screws, followed by cut-out. (4) The investigated augmenting screw technique demonstrated higher failure loads and cycles to failure against cage subsidence compared to conventional cage placement. Failure modes were different between the two techniques and may lead to a different kind of complications. Full article

Background/Objectives: The concept of frailty has been recognized as an important issue which can influence postoperative outcomes. We aimed to investigate the influence of frailty on clinical and radiological outcomes in patients undergoing transforaminal lumbar interbody fusion (TLIF) for degenerative spine disease. Methods: A single-center, retrospective cohort study was conducted involving 408 patients in whom 506 expandable interbody devices were implanted. The patients were grouped into vulnerable/frail versus well/fit according to the Canadian Frailty Index. Results: The frail patients were older and had a larger number of fused segments (3.0 vs. 2.4 segments, p = 0.009). In the univariate analysis, the frail patients were more likely to experience a postoperative adverse event (AE) until discharge (OR 1.89, 95% CI 1.22–2.92; p = 0.004), three (OR 1.57, 1.07–2.3; p = 0.021), and 12 months postoperatively (OR 3.77, 1.96–7.24; p < 0.001). Following the multivariable logistic regression analysis, frailty remained an independent risk factor for postoperative AEs at 12 months (OR 3.44, 95% CI 1.69–6.99; p = 0.001). Conclusions: Frailty negatively influenced the rate of AEs until 12 months, while the odds of having a favorable outcome at any time remained unaffected in patients undergoing posterior spinal fusion with TLIF. Future efforts are needed to evaluate whether preoperative medical optimization or prehabilitation may positively impact patient outcomes. Full article

Background: Mechanomyography (MMG) is a neurodiagnostic technique with a documented ability to evaluate the compression of nerve roots. Its utility in degenerative spine surgery is unknown. Objective: To assess the utility of intraoperative MMG during cervical posterior foraminotomy, minimally invasive transforaminal interbody fusion (MIS-TLIF), and tubular lumbar far lateral discectomy. Methods: A prospective feasibility study was conducted during which MMG was applied during three procedures. Adhesive accelerometers were placed on two muscle groups per procedure. Stimulus threshold in mA was recorded before and after the decompression of the nerve root. Differences in stimulation thresholds were correlated with operative findings. Results: In total, 22 patients were included in this study; 5 patients underwent cervical foraminotomies, 3 underwent MIS-TLIFs, and 14 underwent tubular far lateral discectomies. For the foraminotomies, all cases showed a reduction in stimulation threshold (mean of 3.4 mA) after decompression. For MIS-TLIF cases, there was a limited reduction in the stimulation threshold after decompression (mean 1.7 mA). For far lateral discectomy, there was a mean reduction of 4.3 mA in the stimulation threshold following decompression. Conclusions: MMG is a method that may provide intraoperative feedback on the decompression of nerve roots. In the context of MIS-TLIF, MMG showed a limited decrease in stimulus threshold. This may be due to the identification of the nerve occurring after decompression is already underway. For cervical foraminotomies and far lateral discectomies, MMG showed promising results in determining adequate decompression of the nerve root. Full article

Background and Objectives: Spine surgery has undergone significant advancements, particularly with regard to robotic systems that enhance surgical techniques and improve patient outcomes. As these technologies become increasingly integrated into surgical practice, it is essential to evaluate their added value and cost savings. Hence, this study compared robot-assisted and navigation-based spine surgery, focusing on surgical efficiency. Materials and Methods: We conducted a single-center, retrospective cohort study of patients undergoing single- and double-level transforaminal lumbar interbody fusion (TLIF) and oblique lumbar interbody fusion (OLIF) surgeries. Patients were divided into two groups: those who had robot-assisted and navigation-based surgeries, stratified by surgery type (TLIF or OLIF) and fusion levels (one or two). A comparative analysis of factors related to surgical efficiency, including operative duration, blood loss, and length of hospital stay, was conducted. Results: Our results showed a statistically significant reduction in operative duration for robot-assisted one- and two-level OLIF cases, with average time savings of 50 and 62 min, respectively, compared to navigation-based surgery. These time savings translated to an estimated cost reduction of SGD 1500 for the hospital for each patient for a two-level OLIF procedure and could be higher as the number of operated levels increase. Conclusions: These results indicated that robot-assisted spine surgery offers superior surgical efficiency and cost savings, particularly with increased numbers of surgical levels. As robotic technologies evolve, their integration into spine surgery is justified, promising improved patient outcomes and cost-effectiveness. Full article

Background/Objectives: Cage implantation decompresses neural elements, stabilizes segments, and promotes fusion, with sagittal balance influenced by cage size, geometry, and position. This retrospective study compared the effects of lumbar interbody cages with 10° and 15° lordotic angles on global and segmental lordosis in patients undergoing transforaminal lumbar interbody fusion (TLIF). Methods: Data from 215 patients who underwent 259 TLIF procedures between 2018 and 2022 were analyzed. All the surgeries were performed by a single senior orthopedic spine surgeon, and cages were selected by the surgeon based on patients’ clinical and anatomical factors. Radiographic assessments included measurements of global and segmental lordosis. Results: Patients who received 15° cages demonstrated significantly greater segmental lordosis compared to those who received 10° cages in both bisegmental and monosegmental procedures (p < 0.001). While the global lordosis in the 10°-cage group remained unchanged postoperatively (p = 0.687), bisegmental procedures showed a small but statistically significant increase (p = 0.035). Moreover, global lordosis did not significantly differ between the 10°- and 15°-cage groups. Conclusions: Cage geometry significantly influenced segmental lordosis, with 15° cages achieving overall more superior radiographic results compared to 10° cages. However, global lordosis was unaffected by cage angle, thereby highlighting the multifaceted nature of factors that influence overall spinal alignment. These findings provide valuable insights into lumbar spine surgery, thus emphasizing the need for comprehensive preoperative planning and consideration of individual patient characteristics. Full article

Background/Objectives: Various surgical approaches have been proposed for treating adjacent segment disease (ASD) after lumbar fusion. However, studies using oblique lumbar interbody fusion (OLIF) to treat ASD are lacking. The current study assessed the postoperative outcomes of single-level OLIF for ASD, comparing the results with those for patients undergoing transforaminal lumbar interbody fusion (TLIF). Methods: Patients who underwent single-level OLIF or TLIF for lumbar ASD were retrospectively included. Clinical outcomes, that is, the results of assessments using the Euroqol 5-Dimension quality of life scale (EQ-5D), the Oswestry Disability Index, and the visual analog scale, were evaluated. Radiologic parameters, including disc height (DH), segmental lordosis (SL), segmental coronal angle (SCA), lumbar lordosis, and pelvic incidence–lumbar lordosis mismatch, were also assessed. Results: A total of 65 patients were enrolled: 32 in the OLIF group and 33 in the TLIF group. The median follow-up time was 24.0 months in both groups. The clinical outcomes and radiologic parameters significantly improved in both groups postoperatively. According to intergroup comparisons, the OLIF group had significantly less blood loss and superior improvement in radiologic parameters (DH, SL, and SCA) whereas the TLIF group had significantly shorter operation times. For the OLIF patients who did not undergo posterior decompression, the operation time was similar to that of the TLIF group, but the surgical blood loss and length of hospital stay were significantly reduced compared with the TLIF group. Conclusions: Compared with TLIF, OLIF provides similar clinical outcomes, leads to less surgical blood loss, and has superior radiologic parameters; however, the operation time is significantly longer. OLIF without posterior decompression may be a superior option to TLIF for certain patients. Full article