Tadashi Komatsubara

Background/Objectives: Rigid internal fixation and early mobilization using pedicle screws have become a standard treatment option for vertebral fractures in patients with diffuse idiopathic skeletal hyperostosis. Poor bone quality and a long lever arm may result in a high rate of screw loosening, screw pullout, and implant failure in these patients. Therefore, researchers have developed various techniques to enhance fixation strength, including cement-augmented fenestrated pedicle screw (CAFPS) and transdiscal screw (TDS) fixation. This study compared the clinical and radiological outcomes of CAFPS and TDS fixation techniques for treating diffuse idiopathic skeletal hyperostosis (DISH)-associated thoracolumbar vertebral fractures. This study compared the clinical and radiological outcomes of CAFPS and TDS fixation techniques for DISH-associated thoracolumbar vertebral fractures. Methods: Retrospective comparative cohort study. An evaluation was conducted of patients who underwent posterior instrumentation for vertebral fractures accompanied by DISH, using CAFPS or TDS techniques, at our hospital between August 2019 and March 2025. We assessed preoperative, operative, and postoperative data, outcomes, and radiographic parameters. Results: We included 40 patients; 11 received CAFPS, and 29 received TDS fixation. Operative time (104 ± 19.6 min vs. 115 ± 29.4 min, p = 0.32), blood loss (87.7 ± 69.4 mL vs. 88.3 ± 64.8 mL, p = 0.95), and bone union rate (100% vs. 89.7%, p = 0.27) did not differ significantly. The incidence of screw loosening number was higher in the TDS group (5.68% vs. 13.4%, p = 0.049). However, patient-level analysis showed no difference (4/11 vs. 7/29, p = 0.455). Neither group had implant backouts, failures, or reoperations. Conclusions: Transdiscal screws and transdiscal and cement-augmented pedicle screws are useful techniques for treating thoracolumbar vertebral fractures in patients with DISH. These techniques can reduce the level of fixation in vulnerable patient populations.

Background/Objectives: Vertebral body stenting (VBS) and balloon kyphoplasty (BKP) are widely used for the treatment of osteoporotic vertebral fractures (OVFs). However, it remains unclear whether the theoretical biomechanical advantages of VBS translate to superior clinical or radiographic outcomes. This study aimed to compare VBS and BKP with respect to clinical outcomes, radiographic parameters, and complications. Methods: In this multicenter retrospective comparative cohort study, 123 patients with OVF treated with VBS (n = 24) or BKP (n = 99) were analyzed. VBS was indicated for complex fracture patterns, including severe endplate injury, split-type fractures, and absence of interbody sclerosis; other fractures were treated with BKP. Pain outcomes, operative parameters, cement volume and leakage, and radiographic measures of vertebral kyphosis angle (VKA) and local kyphosis angle (LKA) were assessed. For group comparisons, we used independent-samples t tests or Mann–Whitney U tests for continuous variables and chi-squared or Fisher’s exact tests for categorical variables. Results: Baseline demographics and bone mineral density were comparable between groups. Surgical time was longer for VBS (39 ± 6 vs. 35 ± 9 min, p = 0.007). Both procedures produced significant pain reductions (p < 0.001), and postoperative VAS did not differ between VBS and BKP (18 ± 11 vs. 13 ± 12 mm, p = 0.06). Although VKA immediately after surgery was lower for VBS (4.8 ± 4.4° vs. 7.0 ± 4.9°, p = 0.03), the magnitude of correction, VKA, and LKA at final follow-up were comparable. Cement volume was similar (6.4 ± 1.4 vs. 6.7 ± 1.9 mL, p = 0.45), but cement leakage occurred more frequently with VBS (54% vs. 24%, p = 0.005). Rates of adjacent vertebral fracture (13% vs. 26%, p = 0.12) and revision surgery (4% vs. 8%, p = 0.44) were comparable between groups. Conclusions: Despite VBS being reserved for more complex fracture morphologies with split-type fractures and severe endplate defects, while BKP was generally used for uncomplicated OVF cases, VBS provided pain relief and radiographic correction comparable to BKP.

Background: Intraoperative neurophysiological monitoring (IONM) has become an invaluable tool for spinal deformity surgery. This study aims to present our experience of using transcranial motor evoked potential (Tc-MEP) as an IONM tool in adolescent idiopathic scoliosis patients undergoing navigation-assisted deformity correction and explore the potential risk factors associated with false-positive and true-positive IONM findings. Methods: A retrospective study was conducted in 103 patients (mean age 16.2 ± 4.0 years) undergoing corrective surgery for spinal deformity. All pediatric spinal deformity correction surgeries at the center were performed by a single senior spine surgeon, utilizing navigation and Tc-MEP to enhance the neurological safety profile. The sensitivity and the specificity of Tc-MEP were calculated. Results: Of the total cases, 87 patients (84.5%) exhibited no IONM signal alert and did not experience any postoperative neurological deficits, representing true negatives. There were no false-negative cases, which gives a negative predictive value of 100%. Significant IONM signal alerts were observed in 16 patients (15.5%), but only two patients (1.9%) experienced a postoperative motor deficit, representing true positives, which yielded a positive predictive value of 12.5%. Conclusions: This study demonstrated the sensitivity and specificity of Tc-MEP to be 100% and 86.3%, respectively, with a false-positive rate of 13.7%. Blood loss was the only factor significantly associated with IONM alerts, while age, gender, surgical duration, and anesthetic modality showed no significant differences.

Study Design: Prospective observational study. Background: Lumbar spinal stenosis (LSS) impairs balance and gait function, increasing fall risk and limiting quality of life. Although postoperative recovery of balance is clinically important, longitudinal data using multidimensional balance assessments are limited. Methods: A prospective cohort study was conducted in 101 patients (mean age 74.9 ± 6.9 years) undergoing surgery for LSS. The Brief Balance Evaluation Systems Test (Brief BESTest), Oswestry Disability Index (ODI), Modified Falls Efficacy Scale (MFES), Zurich Claudication Questionnaire (ZCQ), and Visual Analog Scales (VAS) for pain/numbness were evaluated preoperatively and at 6 and 12 months postoperatively. Changes over time and correlations between Brief BESTest and PROMs were analyzed. Results: The total Brief BESTest score significantly improved from 13.3 ± 5.3 preoperatively to 16.1 ± 5.1 at 6 months and 16.0 ± 5.1 at 12 months (p < 0.01). Subdomains including Anticipatory Adjustments, Postural Responses, Sensory Orientation, and Stability in Gait improved significantly, while Stability Limits did not. At 12 months postoperatively, ODI decreased by 19.1%, ZCQ symptom and function scores improved by 0.8 and 0.9 points, respectively, and VAS scores improved by 17.1 mm for low back pain, 26.5 mm for lower limb pain, and 19.5 mm for numbness, all showing marked improvements from baseline. MFES also increased significantly postoperatively. The Brief BESTest score correlated significantly with MFES and ZCQ-PFS at baseline, and with ODI, ZCQ, and VAS scores at 12 months. Conclusions: Balance ability in LSS patients improved after surgery, as measured by the Brief BESTest, with clinically meaningful changes maintained for 12 months. Improvements in balance were significantly associated with reductions in pain, disability, and fear of falling, suggesting the Brief BESTest is a comprehensive indicator of postoperative recovery.

Background and Objectives: We conducted a retrospective observational study. Background: While traditional rehabilitation approaches emphasize trunk muscle conditioning, emerging evidence suggests that leg muscle strength plays a critical role in postoperative functional mobility. Previous studies have focused on trunk muscle rehabilitation in patients with adult spinal deformity (ASD). However, recent findings suggest that leg muscle conditioning may be a better predictor of postoperative improvement. Strengthening the gluteal and iliopsoas muscles has been linked to improved sagittal balance, gait stability, and mobility, ultimately leading to enhanced surgical outcomes. This study examines the relationship between the preoperative functional cross-sectional area (FCSA) of trunk and leg muscles and postoperative improvement in mobility, as assessed by the Timed Up and Go (TUG) test, in patients undergoing surgery for ASD. Materials and Methods: Sixty-two patients (57 women, mean age 71.2 ± 7.1 years) who underwent ASD surgery between April 2017 and April 2024 were retrospectively analyzed. The FCSA of key muscles—psoas major (PM), erector spinae (ES), multifidus (MF), gluteus maximus (GM), and gluteus medius (GMed)—was measured using CT images. Patients were categorized into an improvement group and a non-improvement group based on whether they achieved the minimum clinically important difference (MCID) of −2 s in the TUG test 12 months after surgery. Propensity score matching (PSM) was applied to adjust for baseline differences between the groups. A significance level of 5% was used for all comparisons. Results: Thirty-three patients achieved a clinically meaningful improvement in TUG, while 29 did not. Before PSM, patients with worse preoperative TUG and Oswestry Disability Index (ODI) scores showed greater improvements (p < 0.01). After PSM, no significant differences were found between the groups in terms of age, sex, or BMI. However, the improvement group showed significantly greater FCSA values in PM (6.1 ± 2.3 mm² vs. 3.9 ± 1.5 mm², p = 0.021) and GM (19.9 ± 5.9 mm² vs. 15.3 ± 3.9 mm², p = 0.019). Conclusions: This study demonstrates that leg muscle quality, particularly that of the gluteus maximus and psoas major, is a significant predictor of postoperative mobility improvement in patients with ASD. These findings challenge the conventional focus on trunk muscles and suggest the inclusion of leg muscle training in preoperative rehabilitation strategies to enhance surgical outcomes.

Meticulous clinical examination is essential for spinal disorders to utilize the diagnostic methods and technologies that strongly support physicians and enhance clinical practice. A significant change in the approach to diagnosing spinal disorders has occurred in the last three decades, which has enhanced a more nuanced understanding of spine pathology. Traditional radiographic methods such as conventional and functional X-rays and CT scans are still the first line in the diagnosis of spinal disorders due to their low cost and accessibility. As more advanced imaging technologies become increasingly available worldwide, there is a constantly increasing trend in MRI scans for detecting spinal pathologies and making treatment decisions. Not only do MRI scans have superior diagnostic capabilities, but they also assist surgeons in performing meticulous preoperative planning, making them currently the most widely used diagnostic tool for spinal disorders. Positron Emission Tomography (PET) can help detect inflammatory lesions, infections, and tumors. Other advanced diagnostic tools such as CT/MRI fusion image, Functional Magnetic Resonance Imaging (fMRI), Upright and Kinetic MRI, magnetic resonance spectroscopy (MRS), diffusion-weighted imaging (DWI), and diffusion tensor imaging (DTI) could play an important role when it comes to detecting more special pathologies. However, some technical difficulties in the daily praxis and their high costs act as obstacles to their further spread. Integrating artificial intelligence and advancements in data analytics and virtual reality promises to enhance spinal procedures’ precision, safety, and efficacy. As these technologies continue to develop, they will play a critical role in transforming spinal surgery. This paradigm shift emphasizes the importance of continuous innovation and adaptability in improving the diagnosis and treatment of spinal disorders.

Objective: Postoperative lymphopenia is reported as an excellent indicator to predict surgical-site infection (SSI) after spine surgery. However, there is still controversy concerning which serological markers can predict spinal SSI. This study aims to evaluate excellent and early indicators for detecting SSI, focusing on spine instrumented surgery. Materials and Methods: This study included 268 patients who underwent spinal instrumented surgery from January 2022 to December 2023 (159 female and 109 male, average 62.9 years). The SSI group included 20 patients, and the non-SSI group comprised 248 patients. Surgical time, intraoperative blood loss, and glycemic levels were measured in both groups. The complete blood cell counts, differential counts, albumin, and C-reactive protein (CRP) levels were measured pre-surgery and postoperative on Days 1, 3, and 7. In comparing the groups, the Mann–Whitney U test analysis was used for continuous variables, while the chi-squared test and Fisher’s exact test were used for dichotomous variables. Results: The incidence of SSI after spinal instrumentation was 7.46% and was relatively higher in scoliosis surgery. The SSI group had significantly longer surgical times (248 min vs. 180 min, p = 0.0004) and a higher intraoperative blood loss (772 mL vs. 372 mL, p < 0.0001) than the non-SSI group. In the SSI group, the Day 3 (10.5 ± 6.2% vs. 13.8 ± 6.0%, p = 0.012) and Day 7 (14.4 ± 4.8% vs. 18.8 ± 7.1%, p = 0.012) lymphocyte ratios were lower than the non-SSI group. Albumin levels on Day 1 in the SSI group were lower than in the non-SSI group (2.94 ± 0.30 mg/dL vs. 3.09 ± 0.38 mg/dL, p = 0.045). There is no difference in CRP and lymphocyte count between the two groups. Conclusions: SSI patients had lower lymphocyte percentages than non-SSI patients, which was a risk factor for SSI, with constant high inflammation. The Day 3 lymphocyte percentage may predict SSI after spinal instrumented surgery.

Background/Objectives: We sought to improve accuracy while minimizing radiation hazards, improving surgical outcomes, and preventing potential complications. Despite the increasing popularity of these systems, a limited number of papers have been published addressing the historical evolution, detailing the areas of use, and discussing the advantages and disadvantages, of this increasingly popular system in lumbar spine surgery. Our objective was to offer readers a concise overview of navigation system history in lumbar spine surgeries, the techniques involved, the advantages and disadvantages, and suggestions for future enhancements to the system. Methods: A comprehensive review of the literature was conducted, focusing on the development and implementation of navigation systems in lumbar spine surgeries. Our sources include PubMed-indexed peer-reviewed journals, clinical trial data, and case studies involving technologies such as computer-assisted surgery (CAS), image-guided surgery (IGS), and robotic-assisted systems. Results: To develop more practical, effective, and accurate navigation techniques for spine surgery, consistent advancements have been made over the past four decades. This technological progress began in the late 20th century and has since encompassed image-guided surgery, intraoperative imaging, advanced navigation combined with robotic assistance, and artificial intelligence. These technological advancements have significantly improved the accuracy of implant placement, reducing the risk of misplacement and related complications. Navigation has also been found to be particularly useful in tumor resection and minimally invasive surgery (MIS), where conventional anatomic landmarks are lacking or, in the case of MIS, not visible. Additionally, these innovations have led to shorter operative times, decreased radiation exposure for patients and surgical teams, and lower rates of reoperation. As navigation technology continues to evolve, future innovations are anticipated to further enhance the capabilities and accessibility of these systems, ultimately leading to improved patient outcomes in lumbar spine surgery. Conclusions: The initial limited utilization of navigation system in spine surgery has further expanded to encompass almost all fields of lumbar spine surgeries. As the cost-effectiveness and number of trained surgeons improve, a wider use of the system will be ensured so that the navigation system will be an indispensable tool in lumbar spine surgery. However, continued research and development, along with training programs for surgeons, are essential to fully realize the potential of these technologies in clinical practice.

Spinal cord tumors, though rare, present formidable challenges in clinical management due to their intricate nature. Traditional treatment modalities like surgery, radiation therapy, and chemotherapy have been the mainstay for managing these tumors. However, despite significant advancements, challenges persist, including the limitations of surgical resection and the potential side effects associated with radiation therapy. In response to these limitations, a wave of innovative approaches is reshaping the treatment landscape for spinal cord tumors. Advancements in gene therapy, immunotherapy, and targeted therapy are offering groundbreaking possibilities. Gene therapy holds the potential to modify the genes responsible for tumor growth, while immunotherapy harnesses the body’s own immune system to fight cancer cells. Targeted therapy aims to strike a specific vulnerability within the tumor cells, offering a more precise and potentially less toxic approach. Additionally, novel surgical adjuncts are being explored to improve visualization and minimize damage to surrounding healthy tissue during tumor removal. These developments pave the way for a future of personalized medicine for spinal cord tumors. By delving deeper into the molecular makeup of individual tumors, doctors can tailor treatment strategies to target specific mutations and vulnerabilities. This personalized approach offers the potential for more effective interventions with fewer side effects, ultimately leading to improved patient outcomes and a better quality of life. This evolving landscape of spinal cord tumor management signifies the crucial integration of established and innovative strategies to create a brighter future for patients battling this complex condition.

Background: The aging of the population in developing and developed countries has led to a significant increase in the health burden of spinal diseases. These elderly patients often have a number of medical comorbidities due to aging. The need for minimally invasive techniques to address spinal disorders in this elderly population group cannot be stressed enough. Minimally invasive spine surgery (MISS) has several proven benefits, such as minimal muscle trauma, minimal bony resection, lesser postoperative pain, decreased infection rate, and shorter hospital stay. Methods: A comprehensive search of the literature was performed using PubMed. Results: Over the past 40 years, constant efforts have been made to develop newer techniques of spine surgery. Endoscopic spine surgery is one such subset of MISS, which has all the benefits of modern MISS. Endoscopic spine surgery was initially limited only to the treatment of lumbar disc herniation. With improvements in optics, endoscopes, endoscopic drills and shavers, and irrigation pumps, there has been a paradigm shift. Endoscopic spine surgery can now be performed with high magnification, thus allowing its application not only to lumbar spinal stenosis but also to spinal fusion surgeries and cervical and thoracic pathology as well. There has been increasing evidence in support of these newer techniques of spine surgery. Conclusions: For this report, we studied the currently available literature and outlined the historical evolution of endoscopic spine surgery, the various endoscopic systems and techniques available, and the current applications of endoscopic techniques as an alternative to traditional spinal surgery.