MDPI AG Acta Medica Okayama 2076-2607 14 9 2026 Virotherapy for Spinal and Spinal Cord Tumors: Current Evidence and Future Perspectives 2110 EN Koji Uotani Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Tomohiro Fujiwara Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Ryo Takatori Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kazutaka Yamashita Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kenzaburo Matsumoto Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yoshiaki Oda Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kensuke Shinohara Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hiroshi Tazawa Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshiyoshi Fujiwara Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshifumi Ozaki Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Tumors of the spine and spinal cord, including primary and metastatic vertebral tumors, intramedullary gliomas, and refractory intradural lesions, are challenging to treat because curative local therapy is limited by the eloquent, nonregenerating neural tissue surrounding them. Oncolytic virotherapy may offer a rational alternative by combining tumor-selective oncolysis with the induction of systemic antitumor immunity, while sparing normal neural cells. This review summarizes the current field of oncolytic viruses, including adenovirus, herpes simplex virus, reovirus, and others, in the context of spinal and spinal cord tumors. Clinical data in the spine remain scarce; however, the rationale is based on histological evidence from sarcomas and other tumors, extensive glioma experience, including diffuse intrinsic pontine glioma, and preclinical activity in nerve sheath and meningioma models. We discuss the telomerase-specific oncolytic adenovirus OBP-301 and its derivatives, whose hTERT-driven replication provides histology-agnostic tumor selectivity, while sparing the telomerase-silent spinal cord. This telomerase dependence, however, limits activity against tumors that maintain telomeres through the alternative lengthening of telomeres (ALT) pathway, such as many osteosarcomas and some spinal cord astrocytomas. We also discuss delivery and safety within the confined spinal canal, combination strategies, and future directions, such as extracellular vesicle-mediated delivery and biomarker-guided patient selection. Although clinical translation to the spine will require dedicated preclinical and early-phase studies, virotherapy represents a promising, mechanistically grounded modality for these therapeutically challenging tumors. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2168-8184 17 2 2025 A Rare Course of Chiari Malformation With Large Syringomyelia Presenting at 54 Years Old e78399 EN Masato Tanaka Orthopedic Surgery, Okayama University Hospital Sneha Sharma Orthopedics, North Delhi Municipal Corporation (DMC) Medical College Kushal H Gori Orthopedic Surgery, Okayama Rosai Hospital Md Shohidullah Orthopedic Surgery, Okayama Rosai Hospital Koji Uotani Orthopedic Surgery, Okayama University Hospital Chiari malformation type 1 (CM1) is considered a congenital condition. The symptoms include severe headache, hypalgesia, and loss of temperature sensation. It constitutes a significant burden among children and young adults. The onset of symptoms of CM1 is more commonly observed in relatively young children and is very rare in those over 50 years old. This study aims to present a rare surgical case of CM1 associated with a large syringomyelia in a 54-year-old man. A 54-year-old man with low back pain was introduced to our department. He had slight hyperreflexia of the extremities, slight muscle weakness in both legs, and numbness in the right leg (3/10). He also had urinary and bowel incontinence and spastic gait. Cervical magnetic resonance imaging (MRI) showed CM1 with large syringomyelia extending from C1 to T11. The cervical canal was widened because of a long history of spinal cord expansion. The patient was successfully treated surgically by foramen magnum decompression and syringosubarachnoid shunting under the guidance of O-arm navigation. The muscle weakness and sensory function recovered almost entirely on the one-year follow-up. The patient's cervical Japanese Orthopedic Association (JOA) score had improved from 11/17 to 16/17. Gradually enlarging syringomyelia with slight CM1 is rare, but surgeons should consider this condition's possibility. Foramen magnum decompression achieves good results even in cases with a long history of syringomyelia. This new navigation technique provides an excellent result for a large syringomyelia with CM1. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2168-8184 16 8 2024 Navigation-Guided C-arm-Free Minimally Invasive Transforaminal Lumbar Interbody Fusion: A Comparative Study of Cage Orientation and Screw Insertion Accuracy Against the Conventional C-arm-Assisted Technique e66070 EN Koji Uotani Navigation-Guided C-arm-Free Minimally Invasive Transforaminal Masato Tanaka Department of Orthopaedic Surgery, Okayama Rosai Hospital Chetan Kumawat Department of Orthopaedic Surgery, Okayama Rosai Hospital Sharvari Gunjotikar Department of Orthopaedic Surgery, Okayama Rosai Hospital Yoshiaki Oda Navigation-Guided C-arm-Free Minimally Invasive Transforaminal Kensuke Shinohara Navigation-Guided C-arm-Free Minimally Invasive Transforaminal Tadashi Komatsubara Department of Orthopaedic Surgery, Okayama Rosai Hospital Shinya Arataki Department of Orthopaedic Surgery, Okayama Rosai Hospital Toshifumi Ozaki Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Background: Minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) is a widely utilized technique in spine surgery. This study compares the efficacy and safety of MIS-TLIF performed with traditional C-arm fluoroscopy and C-arm-free O-arm navigation. To the best of our knowledge, our study is the first to compare cage positioning between C-arm-free and C-arm techniques for MIS- TLIF. Methods: A retrospective, comparative analysis was conducted on 43 patients undergoing MIS-TLIF. The group was divided based on the utilization of C-arm fluoroscopy or C-arm-free O-arm navigation. Key parameters analyzed included cage orientation, screw insertion accuracy, operative efficiency, and postoperative recovery. Radiographic measurements were used to assess surgical precision and perioperative complications were documented. Results: The study encompassed 43 patients, with no significant differences in demographic characteristics between the two groups. Surgical time and blood loss were comparable between C-arm-free and C-arm groups. O-arm navigation significantly reduced pedicle screw misplacement (p=0.024). Cage positioning differed between groups (p=0.0063): O-arm cages were mostly mid-center, while C-arm cages were more anterior-center. Such differences in the cage location did not cause any impact on clinical outcome. No significant differences were observed in postoperative complications (screw loosenings, dural tears, surgical site infections) between groups. The Oswestry Disability Index scores at the final follow-up showed no significant difference between the O-arm and C-arm groups, indicating similar levels of postoperative disability. Conclusion: Despite the clinically insignificant difference in cage placement between C-arm-free and C-arm dependent, C-arm-free MIS-TLIF significantly improves screw placement accuracy and reduces radiation exposure to operating stuff. This suggests its potential as a valuable tool for safer and more precise spinal fusion surgery. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2168-8184 16 8 2024 A New Minimally Invasive Technique for Thoracolumbar/Lumbar Focal Kyphosis Due to Osteoporotic Vertebral Fracture: A Case Report e66069 EN Masato Tanaka Department of Orthopedic Surgery, Okayama University Hospital Abd El Kader Al Askar Department of Orthopedic Surgery, Okayama Rosai Hospital Chetan Kumawat Department of Orthopedic Surgery, Okayama Rosai Hospital Shashank J Ekade Department of Orthopedic Surgery, Okayama Rosai Hospital Koji Uotani Department of Orthopedic Surgery, Okayama University Hospital Osteoporotic vertebral fractures are common fractures in the elderly population and are often associated with low back pain and disruption in daily living activities. Reconstruction surgeries, such as corpectomy, are among the treatment options for these conditions. However, a corpectomy requires a longer surgical procedure and involves a significant amount of blood loss. We present the case of an 80-year-old woman with severe low back pain due to an L2 fracture and focal kyphosis treated with a novel minimally invasive technique. The patient underwent anterior and posterior surgery in the right decubitus position using a C-arm-free technique. Hyperlordotic cages were inserted in the upper and lower disc space via a lateral approach, while percutaneous pedicle screws were inserted from a posterior approach. These procedures were performed simultaneously under navigation guidance only. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2168-8184 16 11 2024 Curve Progression After the Termination of Bracing for Adolescent Idiopathic Scoliosis: Usefulness of Combining the Proximal Femur Maturity Index (PFMI) and Risser Staging e73395 EN Hisakazu Shitozawa Department of Orthopaedic Surgery, Section of Medicine, Division of Medicine, Dentistry and Pharmaceutical Sciences, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Haruo Misawa Department of Orthopaedic Surgery, Ryusou Orthopaedic Hospital Koji Uotani Department of Orthopaedic Surgery, Okayama University Hospital Tomoko Tetsunaga Department of Orthopaedic Surgery, Okayama University Hospital Kensuke Shinohara Department of Sports Medicine, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yoshiaki Oda Department of Orthopaedic Surgery, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masataka Ueda Department of Orthopaedic Surgery, Section of Medicine, Division of Medicine, Dentistry and Pharmaceutical Sciences, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Ryo Takatori Department of Orthopaedic Surgery, Section of Medicine, Division of Medicine, Dentistry and Pharmaceutical Sciences, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kazutaka Yamashita Department of Orthopaedic Surgery, Section of Medicine, Division of Medicine, Dentistry and Pharmaceutical Sciences, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Toshifumi Ozaki Department of Orthopaedic Surgery, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Background The brace therapy for adolescent idiopathic scoliosis (AIS) typically ends upon the end of growth. However, determining the timing of growth cessation can be challenging. The purpose of this study was to evaluate the utility of the proximal femur maturity index (PFMI), which can be assessed simultaneously with Risser staging without requiring additional radiation exposure, in determining the appropriate timing to terminate bracing. To achieve this, we investigated the relationship between skeletal maturity at the end of bracing, post-bracing curve progression, and height growth in patients who had been successfully treated with a brace. Methods Between April 2010 and March 2021, a total of 84 female patients with AIS who started bracing at our hospital with an initial Cobb angle of 20-40 degrees were included. All patients were followed for at least one year after brace termination. Height and radiographic parameters (Risser staging, PFMI, Cobb angle) were retrospectively collected. Results At the end of the bracing period, patients were categorized into Risser stage 4 (85.7%) and 5 (14.3%). By the last follow-up, patients with Risser stage 4 experienced an average main curve progression of 1.8°, whereas those with Risser stage 5 had an average progression of －0.3° (P = 0.03). Patients with Risser stage 4 were further divided into PFMI grade 5 (59.7%) and 6 (40.3%). Significant curve progression was observed in patients with PFMI grade 5 (average: 3.0°) compared to grade 6 (average: -0.6°) (P < 0.0001). The mean height growth was 1.9 cm/year for PFMI grade 5, and 0.3 cm/year for grade 6, with significant differences between these groups (P < 0.001). Conclusions PFMI allowed further categorization within Risser stage 4: PFMI grade 5 indicated remaining growth potential and risk of postbracing curve progression, whereas grade 6 indicated growth cessation. The combined use of Risser staging and PFMI, both evaluable through the same whole-spine radiograph, may provide a more accurate prediction of growth cessation. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 2572-1143 9 1 2026 Mechanosensitive Ion Channel PIEZO1 Suppresses BMP2-Induced Ossification of the Annulus Fibrosus Cells e70168 EN Hisakazu Shitozawa Department of Orthopaedic Surgery, Science of Functional Recovery and Reconstruction, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Ryo Nakamichi Department of Orthopaedic Surgery, Okayama University Graduate School Medicine, Dentistry, and Pharmaceutical Sciences Aki Yoshida Department of Orthopaedic Surgery, Science of Functional Recovery and Reconstruction, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masataka Ueda Department of Orthopaedic Surgery, Science of Functional Recovery and Reconstruction, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Taichi Saito Department of Orthopaedic Surgery, Okayama University Hospital Koji Uotani Department of Orthopaedic Surgery, Okayama University Hospital Yoshiaki Oda Department of Orthopaedic Surgery, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Ryo Takatori Department of Orthopaedic Surgery, Science of Functional Recovery and Reconstruction, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kazutaka Yamashita Department of Orthopaedic Surgery, Science of Functional Recovery and Reconstruction, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshifumi Ozaki Department of Orthopaedic Surgery, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Objective: Major cause of low-back pain is intervertebral disc degeneration (IVDD), with mechanical stress playing a crucial role in its progression. A mechanosensitive ion channel, PIEZO1, is involved in various musculoskeletal tissues, but its role in the annulus fibrosus (AF) remains unclear. This study aimed to elucidate the function of PIEZO1 in AF cells under mechanical stimulation. Methods: Primary rat AF cells were subjected to cyclic tensile strain (CTS) at low (2%) and high (12%) strain levels to investigate strain-dependent effects on osteogenic gene expression. We evaluated the effects of Piezo1, Piezo2, and Trpv4 knockdown by RNA interference to identify the upstream mechanotransducer. Furthermore, PIEZO1 was activated using the agonist Yoda1, followed by RNA-sequencing analysis and evaluation of its effects on BMP2-induced osteogenesis in rat AF cells. We also examined the effects of Yoda1 in primary human AF cells. Results: Low-strain CTS significantly suppressed osteogenic marker expression, which was not observed with high strain. Piezo1 knockdown reversed this suppression, whereas Piezo2 and Trpv4 had no effect. Piezo1 activation by Yoda1 produced similar anti-osteogenic effects in both rat and human AF cells. RNA sequencing revealed the enrichment of ossification and calcineurin signaling pathways in rat cells. Furthermore, Piezo1 activation inhibited BMP2-induced osteogenesis and nuclear translocation of p-Smad1/5/9. Conclusions: Piezo1 maintains AF cell homeostasis under mechanical stress by suppressing osteogenic changes via calcineurin-mediated inhibition of BMP signaling, which may represent a novel therapeutic target for IVDD. No potential conflict of interest relevant to this article was reported.

International Institute of Anticancer Research Acta Medica Okayama 0250-7005 46 1 2025 P53-Armed Oncolytic Virotherapy Promotes the Efficacy of PD1 Blockade in Murine Osteosarcoma Tumors 69 84 EN MIHO KURE Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences HIROSHI TAZAWA Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences KOJI DEMIYA Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences HIROYA KONDO Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences YUSUKE MOCHIZUKI Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences TADASHI KOMATSUBARA Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences AKI YOSHIDA Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences KOJI UOTANI Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences JOE HASEI Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences TOMOHIRO FUJIWARA Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences TOSHIYUKI KUNISADA Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences YASUO URATA Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences SHUNSUKE KAGAWA Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences TOSHIFUMI OZAKI Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences TOSHIYOSHI FUJIWARA Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Background/Aim: Osteosarcoma (OS) is refractory to immune checkpoint inhibitors targeting programmed cell death 1 (PD1)/PD ligand 1 (PD-L1) due to poor immune response. We previously developed telomerase-specific, replication-competent oncolytic adenoviruses non-armed OBP-301 and P53-armed OBP-702 that exert antitumor efficacy against human OS cells. Recently, we demonstrated that P53-armed OBP-702 induces more profound immunogenic cell death and antitumor immune response against human and murine OS cells than does non-armed OBP-301. In the present study, we assessed the combined efficacy of PD1 blockade and P53-armed OBP-702 against murine OS cells. Materials and Methods: Three murine OS cell lines (K7M2, NHOS, NHOS-LM4) were used to assess the cytopathic effect of non-armed OBP-301 and P53-armed OBP-702 by XTT assay. Virus-induced immunogenic cell death was assessed by analyzing the levels of extracellular adenosine triphosphate and high-mobility group box protein B1. The expression of PD-L1 and PD-L2 was analyzed by flow cytometry. The malignant potential of NHOS-LM4 cells was analyzed by a migration and invasion assay. An orthotopic NHOS-LM4 tumor model was used to evaluate the antitumor efficacy of combination therapy with P53-armed OBP-702 and anti-PD1. Results: P53-armed OBP-702 exhibited antitumor potential for the induction of immunogenic cell death, apoptosis, autophagy, and PD-L1/2 upregulation in K7M2 and NHOS cells. NHOS-LM4 cells showed increased migratory and invasive ability compared to NHOS cells. P53-armed OBP-702 significantly suppressed the malignant potential of NHOS-LM4 cells. Combination dosing showed that P53-armed OBP-702 significantly promoted the antitumor effect of PD1 blockade against NHOS-LM4 tumors. Conclusion: Our results suggest that P53-armed OBP-702 is a promising agent for improving the antitumor effect of PD1 blockade in treating invasive OS. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2168-8184 17 6 2025 Clinical Outcomes and Biomechanical Evaluation of the Cement-Catching Screw Technique for Osteoporotic Vertebral Fractures e85955 EN Hisakazu Shitozawa Department of Orthopaedic Surgery, Science of Functional Recovery and Reconstruction, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Haruo Misawa Department of Orthopaedic Surgery, Ryusou Orthopaedic Hospital Yoshiaki Oda Department of Orthopaedic Surgery, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Ryoji Joko Department of Orthopaedic Surgery, Japanese Red Cross Okayama Hospital Masaya Takahashi Department of Orthopaedic Surgery, Japanese Red Cross Okayama Hospital Koji Uotani Department of Orthopaedic Surgery, Okayama University Hospital Yasuyuki Shiozaki Department of Orthopaedic surgery, Mitoyo General Hospital Tomoko Tetsunaga Department of Orthopaedic Surgery, Okayama University Hospital Kensuke Shinohara Department of Sports Medicine, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Ryo Nakamichi Department of Orthopaedic Surgery, Okayama University Hospital Masataka Ueda Department of Orthopaedic Surgery, Science of Functional Recovery and Reconstruction, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Ryo Takatori Department of Orthopaedic Surgery, Science of Functional Recovery and Reconstruction, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kazutaka Yamashita Department of Orthopaedic Surgery, Science of Functional Recovery and Reconstruction, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshifumi Ozaki Department of Orthopaedic Surgery, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Objectives: We developed a cement-catching screw (CCS) technique for pedicle screw insertion into hardened cement, connecting anterior and posterior vertebral elements during balloon kyphoplasty (BKP) for osteoporotic vertebral fractures (OVFs). This study reports the CCS technique, clinical outcomes, and biomechanical properties. Methods: This retrospective study included 59 patients (20 men, 39 women; mean age, 77.4 ± 8.7 years) who underwent BKP with one-above-one-below posterior fixation for OVFs between 2020 and 2023. Patients were divided into CCS (－) (without intermediate screws, n = 28) and CCS (+) (with intermediate CCSs, n = 31) groups. Clinical and radiographic outcomes, including activities of daily living, vertebral wedge angle (VWA), surgical level Cobb angle (CA), anterior vertebral body height (AVBH), screw loosening, pullout, and adjacent vertebral fractures, were evaluated preoperatively, postoperatively, and at the final follow-up (≥6 months). Biomechanical pullout strength was assessed at different insertion depths (5, 10, and 15 mm) using polymethylmethacrylate cement. Results: No significant differences were observed between groups in age, sex, follow-up duration, or blood loss; however, the operation time was significantly longer in the CCS (+) group than in the CCS (－) group (P < 0.0001). Radiographic outcomes showed no significant differences in the VWA, CA, AVBH, adjacent vertebral fracture rates, and reoperation rates. However, the incidence of adjacent pedicle screws loosening and pullout was significantly higher in the CCS (－) group than in the CCS (+) group (P = 0.046 and 0.0084, respectively). The correction loss of the CA was significantly lower in the CCS (+) group (CCS (－), 5.6° ± 4.8°; CCS (+), 3.5° ± 4.8°, P = 0.023). The biomechanical test revealed pullout strengths of 683 ± 164, 2231 ± 208, and 3477 ± 393 N for insertion depths of 5, 10, and 15 mm, respectively, with significant increases by depth (P = 0.003 and 0.009). Conclusions: The CCS technique improves anterior-posterior vertebral body stability, enhances fixation strength, and contributes to better surgical outcomes in OVFs treatment. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2168-8184 17 3 2025 A Case of Charcot Spine Arthropathy at the Lumbosacral Level in a Patient With Ankylosis of the Spine e80656 EN Yoshiaki Oda Department of Orthopedic Surgery, Okayama University Hospital Koji Uotani Department of Musculoskeletal Traumatology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Tomoko Tetsunaga Department of Orthopedic Surgery, Okayama University Hospital Kensuke Shinohara Department of Orthopedic Surgery, Okayama University Hospital Toshifumi Ozaki Department of Orthopedic Surgery, Faculty of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University Charcot spinal arthropathy, a rare refractory progressive disease, is characterized by symptoms such as pain, deformity, and neurological impairment, which can significantly reduce functional ability, quality of life, and life expectancy. We report a case of Charcot spine at the L5/S1 level with long segment ankylosis to the L5 vertebra. We first performed thorough debridement via a posterior approach. We used antibiotic-containing cement as a spacer to fill the dead space, facilitating the second surgery approach. In the second surgery, transdiscal screws, which have a low profile and strong force, were used as anchors, and bulk bone harvested from both iliac bones was grafted to the intervertebral space. The lumbosacral alignment was kyphotic, and the patient could sit and move independently. Disimpaction was impossible, and a stoma had to be created. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2045-2322 15 1 2025 The significance of adding posterior decompression to spine stabilization in metastatic spinal surgery: a multicenter prospective study 27684 EN Hiroyuki Tominaga Department of Orthopaedic Surgery, Graduate School of Medical and Dental Sciences, Kagoshima University Ichiro Kawamura Department of Orthopaedic Surgery, Graduate School of Medical and Dental Sciences, Kagoshima University Hirofumi Shimada Department of Orthopaedic Surgery, Graduate School of Medical and Dental Sciences, Kagoshima University Hiromi Sasaki Department of Orthopaedic Surgery, Graduate School of Medical and Dental Sciences, Kagoshima University Noboru Taniguchi Department of Orthopaedic Surgery, Graduate School of Medical and Dental Sciences, Kagoshima University Yuki Shiratani Department of Orthopaedic Surgery, Graduate School of Medicine, Chiba University Akinobu Suzuki Department of Orthopaedic Surgery, Osaka Metropolitan University Hidetomi Terai Department of Orthopaedic Surgery, Osaka Metropolitan University Takaki Shimizu Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kanazawa University Kenichiro Kakutani Department of Orthopaedic Surgery, Kobe University Graduate School of Medicine Yutaro Kanda Department of Orthopaedic Surgery, Kobe University Graduate School of Medicine Masayuki Ishihara Department of Orthopaedic Surgery, Kansai Medical University Hospital Masaaki Paku Department of Orthopaedic Surgery, Kansai Medical University Hospital Yohei Takahashi Department of Orthopaedic Surgery, Keio University Toru Funayama Department of Orthopaedic Surgery, Institute of Medicine, University of Tsukuba Kousei Miura Department of Orthopaedic Surgery, Institute of Medicine, University of Tsukuba Eiki Shirasawa Department of Orthopaedic Surgery, Kitasato University School of Medicine Hirokazu Inoue Rehabilitation Center, Jichi Medical University Hospital Atsushi Kimura Department of Orthopaedics, Jichi Medical University Takuya Iimura Department of Orthopaedic Surgery, Dokkyo Medical University Hiroshi Moridaira Department of Orthopaedic Surgery, Dokkyo Medical University Hideaki Nakajima Department of Orthopaedics and Rehabilitation Medicine, Faculty of Medical Sciences, University of Fukui Shuji Watanabe Department of Orthopaedics and Rehabilitation Medicine, Faculty of Medical Sciences, University of Fukui Koji Akeda Department of Orthopaedic Surgery, Mie University Graduate School of Medicine Norihiko Takegami Department of Orthopaedic Surgery, Mie University Graduate School of Medicine Kazuo Nakanishi Department of Orthopaedic Surgery, Kawasaki Medical School Hirokatsu Sawada Department of Orthopaedic Surgery, Nihon University School of Medicine Koji Matsumoto Department of Orthopaedic Surgery, Nihon University School of Medicine Masahiro Funaba Department of Orthopaedics Surgery, Yamaguchi University Graduate school of Medicine Hidenori Suzuki Department of Orthopaedics Surgery, Yamaguchi University Graduate school of Medicine Haruki Funao Department of Orthopaedic Surgery, International University of Health and Welfare Narita Hospital Tsutomu Oshigiri Department of Orthopaedic Surgery, Sapporo Medical University School of Medicine Takashi Hirai Department of Orthopedic Surgery, Institute of Science Tokyo Bungo Otsuki Department of Orthopaedic Surgery, Kyoto University Hospital Kazu Kobayakawa Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University Koji Uotani Department of Orthopaedic Surgery, Okayama University Hospital Hiroaki Manabe Department of Orthopedics, Tokushima University Shinji Tanishima Division of Orthopedic Surgery, Department of Sensory and Motor Organs, School of Medicine, Faculty of Medicine, Tottori University Ko Hashimoto Department of Orthopaedic Surgery, Tohoku University Graduate School of Medicine Chizuo Iwai Department of Orthopaedic Surgery, Gifu University Hospital Daisuke Yamabe Department of Orthopaedic Surgery, Iwate Medical University Akihiko Hiyama Department of Orthopaedic Surgery, Tokai University School of Medicine Shoji Seki Department of Orthopaedic Surgery, University of Toyama Yuta Goto Department of Orthopaedic Surgery, Nagoya City University Masashi Miyazaki Department of Orthopaedic Surgery, Faculty of Medicine, Oita University Kazuyuki Watanabe Department of Orthopaedic Surgery, Fukushima Medical University School of Medicine Toshio Nakamae Department of Orthopaedic Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University Takashi Kaito Department of Orthopedic Surgery, Osaka University Graduate School of Medicine Hiroaki Nakashima Department of Orthopaedic Surgery, Nagoya University Graduate School of Medicine Narihito Nagoshi Department of Orthopaedic Surgery, Keio University Satoshi Kato Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kanazawa University Shiro Imagama Department of Orthopaedic Surgery, Nagoya University Graduate School of Medicine Kota Watanabe Department of Orthopaedic Surgery, Keio University Gen Inoue Department of Orthopaedic Surgery, Kitasato University School of Medicine Takeo Furuya Department of Orthopaedic Surgery, Graduate School of Medicine, Chiba University The usefulness of spine stabilization for treating metastatic spinal tumors with tumor-induced instability has been reported. However, no reports have prospectively evaluated the effectiveness of adding posterior decompression to stabilization surgery for improving symptoms. This multicenter prospective study aimed to determine whether adding posterior decompression to spine stabilization surgery for metastatic spinal tumors affects postoperative outcomes and complications. A total of 263 patients who underwent spine stabilization with (n = 189) or without (n = 74) decompression were analyzed. Patient demographics, the Spinal Instability Neoplastic Score (SINS), and the Epidural Spinal Cord Compression (ESCC) score were recorded. The outcomes were assessed preoperatively and at 1 and 6 months postoperatively in terms of neurological status, the Barthel Index, the EQ-5D-5 L, and the visual analog scale (VAS). Decompression was primarily performed in patients with severe neurological deficits and high-grade ESCC. Both groups showed postoperative improvement. Propensity score matching was applied to adjust for baseline differences. After matching, there were no significant differences in functional improvement between the decompression and nondecompression groups, and the complication rates were comparable. In matched patients presenting primarily with spinal instability and pain, the addition of decompression did not appear to confer a significant functional benefit within 6 months postoperatively. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2045-2322 15 1 2025 Survival days of patients with metastatic spinal tumors of lung cancer requiring surgery: a prospective multicenter study 24117 EN Takuya Takahashi Department of Orthopedic Surgery, Institute of Science Tokyo Takashi Hirai Department of Orthopedic Surgery, Institute of Science Tokyo Yuki Shiratani Department of Orthopaedic Surgery, Graduate School of Medicine, Chiba University Akinobu Suzuki Department of Orthopaedic Surgery, Osaka Metropolitan University Kenichiro Kakutani Department of Orthopaedic Surgery, Kobe University Graduate School of Medicine Satoshi Kato Department of Orthopaedic Surgery Graduate School of Medical Sciences, Kanazawa University Hiroyuki Tominaga Department of Orthopedic Surgery Graduate School of Medical and Dental Sciences, Kagoshima University Hirokazu Inoue Rehabilitation Center, Jichi Medical University Hospital Hirokatsu Sawada Department of Orthopaedic Surgery, Nihon University School of Medicine Norihiko Takegami Department of Orthopaedic Surgery, Mie University Graduate School of Medicine Kazuo Nakanishi Department of Orthopaedic Surgery, Kawasaki Medical School Hideaki Nakajima Department of Orthopaedics and Rehabilitation Medicine, Faculty of Medical Sciences, University of Fukui Masayuki Ishihara Department of Orthopaedic surgery, Kansai Medical University Hospital Tsutomu Oshigiri Department of Orthopaedic Surgery, Sapporo Medical University School of Medicine Toru Funayama Department of Orthopaedic Surgery Institute of Medicine, University of Tsukuba Takuya Iimura Department of Orthopaedic Surgery, Dokkyo Medical University Shinji Tanishima Division of Orthopedic Surgery, Department of Sensory and Motor Organs, School of Medicine, Faculty of Medicine, Tottori University Hiroaki Nakashima Department of Orthopaedic Surgery, Nagoya University Graduate School of Medicine Daisuke Yamabe Department of Orthopaedic Surgery, Iwate Medical University Ko Hashimoto Department of Orthopaedic Surgery, Tohoku University Graduate School of Medicine Koji Uotani Department of Orthopaedic Surgery, Okayama University Hospital Masahiro Funaba Department of Orthopaedics Surgery, Yamaguchi University Graduate school of Medicine Narihito Nagoshi Department of Orthopaedic Surgery, Keio University Kazu Kobayakawa Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University Toshitaka Yoshii Department of Orthopedic Surgery, Institute of Science Tokyo Kazuyuki Watanabe Department of Orthopaedic Surgery, Fukushima Medical University School of Medicine Toshio Nakamae Department of Orthopaedic Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University Takashi Kaito Department of Orthopedic Surgery, Osaka University Graduate School of Medicine Gen Inoue Department of Orthopaedic Surgery, Kitasato University School of Medicine Shiro Imagama Department of Orthopaedic Surgery, Nagoya University Graduate School of Medicine Kota Watanabe Department of Orthopaedic Surgery, Keio University Takeo Furuya Department of Orthopaedic Surgery, Graduate School of Medicine, Chiba University Surgery for metastatic spinal tumors has improved postoperative activities of daily living. A few studies reported on prognostic factors assessed in large multicenter prospective studies for metastatic spinal tumors of lung cancer origin. This study aimed to determine preoperative prognostic factors in patients undergoing surgery for metastatic spinal tumors associated with lung cancer. This prospective registry study included 74 patients diagnosed and operated with metastatic spine tumors derived from lung cancer in 39 high-volume cancer centers. We examined the postoperative survival period and the preoperative factors related to postoperative survival time. We conducted univariate and multivariate Cox regression analyses to determine preoperative prognostic factors. The mean postoperative survival period was 343 days. Multivariate Cox regression analysis revealed a higher feeding score of vitality index, indications for molecularly targeted therapy, and a higher mobility score of Barthel index as independent factors associated with postoperative survival time in metastatic spinal tumors derived from lung cancer. Patients with indications for molecular-targeted therapy and good vitality exhibited longer survival. These results may help in surgical selection for patients with metastatic spinal tumors derived from lung cancer. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 2075-4418 15 5 2025 Review Article: Diagnostic Paradigm Shift in Spine Surgery 594 EN Aras Efe Levent Department of Orthopedic Surgery, Okayama Rosai Hospital Masato Tanaka Department of Orthopedic Surgery, Okayama Rosai Hospital Chetan Kumawat Department of Orthopedic Surgery, Okayama Rosai Hospital Christian Heng Department of Orthopedic Surgery, Okayama Rosai Hospital Salamalikis Nikolaos Department of Orthopedic Surgery, Okayama Rosai Hospital Kajetan Latka Department of Orthopedic Surgery, Okayama Rosai Hospital Akiyoshi Miyamoto Department of Orthopedic Surgery, Okayama Rosai Hospital Tadashi Komatsubara Department of Orthopedic Surgery, Okayama Rosai Hospital Shinya Arataki Department of Orthopedic Surgery, Okayama Rosai Hospital Yoshiaki Oda Department of Orthopedic Surgery, Okayama University Hospital Kensuke Shinohara Department of Orthopedic Surgery, Okayama University Hospital Koji Uotani Department of Orthopedic Surgery, Okayama University Hospital 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. No potential conflict of interest relevant to this article was reported.

SAGE Publications Acta Medica Okayama 2192-5682 15 4 2024 Effects of Palliative Surgical Treatment for Spinal Metastases on the Patient’s Quality of Life With a Focus on the Segment of the Metastasis: A Prospective Multicenter Study 2286 2299 EN Naoki Segi Department of Orthopaedic Surgery, Nagoya University Graduate School of Medicine Hiroaki Nakashima Department of Orthopaedic Surgery, Nagoya University Graduate School of Medicine Sadayuki Ito Department of Orthopaedic Surgery, Nagoya University Graduate School of Medicine Jun Ouchida Department of Orthopaedic Surgery, Nagoya University Graduate School of Medicine Yuki Shiratani Department of Orthopaedic Surgery, Chiba University Hospital Takaki Shimizu Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kanazawa University Akinobu Suzuki Department of Orthopaedic Surgery, Osaka Metropolitan University Hidetomi Terai Department of Orthopaedic Surgery, Osaka Metropolitan University Kenichiro Kakutani Department of Orthopaedic Surgery, Kobe University Graduate School of Medicine Yutaro Kanda Department of Orthopaedic Surgery, Kobe University Graduate School of Medicine Hiroyuki Tominaga Department of Orthopedic Surgery, Graduate School of Medical and Dental Sciences, Kagoshima University Ichiro Kawamura Department of Orthopedic Surgery, Graduate School of Medical and Dental Sciences, Kagoshima University Masayuki Ishihara Department of Orthopaedic Surgery, Kansai Medial University Hospital Masaaki Paku Department of Orthopaedic Surgery, Kansai Medial University Hospital Yohei Takahashi Department of Orthopaedic Surgery, Keio University Masahiro Funaba Department of Orthopaedics Surgery, Yamaguchi University Graduate school of Medicine Toru Funayama Department of Orthopaedic Surgery, Institute of Medicine, University of Tsukuba Hideaki Nakajima Department of Orthopaedics and Rehabilitation Medicine, University of Fukui Faculty of Medical Sciences Koji Akeda Department of Orthopaedic Surgery, Mie University Graduate School of Medicine Takashi Hirai Department of Orthopedic Surgery, Tokyo Medical and Dental University Hirokazu Inoue Rehabilitation Center, Jichi Medical University Hospital Kazuo Nakanishi Department of Orthopaedic Surgery, Kawasaki Medical School Haruki Funao Department of Orthopaedic Surgery, International University of Health and Welfare Narita Hospital Tsutomu Oshigiri Department of Orthopaedic Surgery, Sapporo Medical University School of Medicine Bungo Otsuki Department of Orthopaedic Surgery, Kyoto University Hospital Kazu Kobayakawa Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University Shinji Tanishima Division of Orthopedic Surgery, Department of Sensory and Motor Organs, School of Medicine, Faculty of Medicine, Tottori University Ko Hashimoto Department of Orthopaedic Surgery, Tohoku University Graduate School of Medicine Takuya Iimura Department of Orthopaedic Surgery, Dokkyo Medical University Hirokatsu Sawada Department of Orthopaedic Surgery, Nihon University School of Medicine Koji Uotani Department of Orthopaedic Surgery, Okayama University Hospital Hiroaki Manabe Department of Orthopedics, Tokushima University Chizuo Iwai Department of Orthopaedic Surgery, Gifu University Hospital Daisuke Yamabe Department of Orthopaedic Surgery, Iwate Medical University Akihiko Hiyama Department of Orthopaedic Surgery, Tokai University School of Medicine Shoji Seki Department of Orthopaedic Surgery, University of Toyama Yuta Goto Department of Orthopaedic Surgery, Nagoya City University Masashi Miyazaki Department of Orthopaedic Surgery, Faculty of Medicine, Oita University Kazuyuki Watanabe Department of Orthopaedic Surgery, Fukushima Medical University School of Medicine Toshio Nakamae Department of Orthopaedic Surgery, Graduate School of Biomedical and Health Sciences, Hiroshima University Takashi Kaito Department of Orthopaedic Surgery, Osaka University Graduate School of Medicine Narihito Nagoshi Department of Orthopaedic Surgery, Keio University Satoshi Kato Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kanazawa University Kota Watanabe Department of Orthopaedic Surgery, Keio University Shiro Imagama Department of Orthopaedic Surgery, Nagoya University Graduate School of Medicine Gen Inoue Department of Orthopaedic Surgery, Kitasato University School of Medicine Takeo Furuya Department of Orthopaedic Surgery, Chiba University Hospital Study Design: Prospective multicenter study. Objectives: Palliative surgery is crucial for maintaining the quality of life (QOL) in patients with spinal metastases. This study aimed to compare the short-term outcomes of QOL after palliative surgery between patients with metastatic spinal tumors at different segments. Methods: We prospectively compared the data of 203 patients with spinal metastases at 2-3 consecutive segments who were divided into the following three groups: cervical, patients with cervical spine lesions; thoracic, patients with upper–middle thoracic spine lesions; and TL/L/S, patients with lesions at the thoracolumbar junction and lumbar and sacral regions. Preoperative and postoperative EuroQol 5-dimension (EQ5D) 5-level were compared. Results: All groups exhibited improvement in the Frankel grade, performance status, pain, Barthel index, EQ5D health state utility value (HSUV), and EQ5D visual analog scale (VAS) postoperatively. Although preoperative EQ5D HSUVs did not significantly differ between the groups (cervical, 0.461 ± 0.291; thoracic, 0.321 ± 0.292; and TL/L/S, 0.376 ± 0.272), the thoracic group exhibited significantly lower postoperative EQ5D HSUVs than the other two groups (cervical, 0.653 ± 0.233; thoracic, 0.513 ± 0.252; and TL/L/S, 0.624 ± 0.232). However, postoperative EQ5D VAS was not significantly different between the groups (cervical, 63.4 ± 25.8; thoracic, 54.7 ± 24.5; and TL/L/S, 61.7 ± 21.9). Conclusions: Palliative surgery for metastatic spinal tumors provided comparable QOL improvement, irrespective of the spinal segment involved. Patients with upper and middle thoracic spinal metastases had poorer QOL outcomes than those with metastases in other segments; however, sufficient QOL improvement was achieved. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 1648-9144 60 4 2024 A Novel Technique for Basilar Invagination Treatment in a Patient with Klippel–Feil Syndrome: A Clinical Example and Brief Literature Review 616 EN Masato Tanaka Department of Orthopaedic Surgery, Okayama Rosai Hospital Abd El Kader Al Askar Department of Orthopaedic Surgery, Okayama Rosai Hospital Chetan Kumawat Department of Orthopaedic Surgery, Okayama Rosai Hospital Shinya Arataki Department of Orthopaedic Surgery, Okayama Rosai Hospital Tadashi Komatsubara Department of Orthopaedic Surgery, Okayama Rosai Hospital Takuya Taoka Department of Orthopaedic Surgery, Okayama Rosai Hospital Koji Uotani Department of Orthopaedic Surgery, Okayama University Hospital Yoshiaki Oda Department of Orthopaedic Surgery, Okayama University Hospital Objectives and Background: To present a novel technique of treatment for a patient with basilar invagination. Basilar invagination (BI) is a congenital condition that can compress the cervicomedullary junction, leading to neurological deficits. Severe cases require surgical intervention, but there is debate over the choice of approach. The anterior approach allows direct decompression but carries high complication rates, while the posterior approach provides indirect decompression and offers good stability with fewer complications. Materials and Methods: A 15-year-old boy with severe myelopathy presented to our hospital with neck pain, bilateral upper limb muscle weakness, and hand numbness persisting for 4 years. Additionally, he experienced increased numbness and gait disturbance three months before his visit. On examination, he exhibited hyperreflexia in both upper and lower limbs, muscle weakness in the bilateral upper limbs (MMT 4), bilateral hypoesthesia below the elbow and in both legs, mild urinary and bowel incontinence, and a spastic gait. Radiographs revealed severe basilar invagination (BI). Preoperative images showed severe BI and that the spinal cord was severely compressed with odontoid process. Results: The patient underwent posterior surgery with the C-arm free technique. All screws including occipital screws were inserted into the adequate position under navigation guidance. Reduction was achieved with skull rotation and distraction. A follow-up at one year showed the following results: Manual muscle testing results and sensory function tests showed almost full recovery, with bilateral arm recovery (MMT 5) and smooth walking. The cervical Japanese Orthopedic Association score of the patient improved from 9/17 to 16/17. Postoperative images showed excellent spinal cord decompression, and no major or severe complications had occurred. Conclusions: Basilar invagination alongside Klippel–Feil syndrome represents a relatively uncommon condition. Utilizing a posterior approach for treating reducible BI with a C-arm-free technique proved to be a safe method in addressing severe myelopathy. This novel navigation technique yields excellent outcomes for patients with BI. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 2075-4418 14 23 2024 Predicting Surgical Site Infections in Spine Surgery: Association of Postoperative Lymphocyte Reduction 2715 EN Akiyoshi Miyamoto Department of Orthopedic Surgery, Okayama Rosai Hospital Masato Tanaka Department of Orthopedic Surgery, Okayama Rosai Hospital Angel Oscar Paz Flores Department of Orthopedic Surgery, Okayama Rosai Hospital Dongwoo Yu Department of Orthopedic Surgery, Okayama Rosai Hospital Mukul Jain Department of Orthopedic Surgery, Okayama Rosai Hospital Christan Heng Department of Orthopedic Surgery, Okayama Rosai Hospital Tadashi Komatsubara Department of Orthopedic Surgery, Okayama Rosai Hospital Shinya Arataki Department of Orthopedic Surgery, Okayama Rosai Hospital Yoshiaki Oda Department of Orthopedic Surgery, Okayama University Hospital Kensuke Shinohara Department of Orthopedic Surgery, Okayama University Hospital Koji Uotani Department of Orthopedic Surgery, Okayama University Hospital 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. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 1648-9144 60 4 2024 Retrospective Cohort Study of Early versus Delayed Ballon Kyphoplasty Intervention for Osteoporotic Vertebral Fracture Treatment 519 EN Akiyoshi Miyamoto Department of Orthopaedic Surgery, Okayama Rosai Hospital Umesh Parihar Department of Orthopaedic Surgery, Okayama Rosai Hospital Chetan Kumawat Department of Orthopaedic Surgery, Okayama Rosai Hospital Abd El Kader Al Askar Department of Orthopaedic Surgery, Okayama Rosai Hospital Masato Tanaka Department of Orthopaedic Surgery, Okayama Rosai Hospital Sharvari Gunjotikar Department of Orthopaedic Surgery, Okayama Rosai Hospital Takuya Taoka Department of Orthopaedic Surgery, Okayama Rosai Hospital Tadashi Komatsubara Department of Orthopaedic Surgery, Okayama Rosai Hospital Yoshihiro Fujiwara Department of Orthopaedic Surgery, Okayama Rosai Hospital Koji Uotani Department of Orthopaedic Surgery, Okayama University Hospital Shinya Arataki Department of Orthopaedic Surgery, Okayama Rosai Hospital Objectives: To investigate the outcomes of early balloon kyphoplasty (BKP) intervention compared with late intervention for osteoporotic vertebral fracture (OVF). Background: Osteoporotic vertebral fracture can lead to kyphotic deformity, severe back pain, depression, and disturbances in activities of daily living (ADL). Balloon kyphoplasty has been widely utilized to treat symptomatic OVFs and has proven to be a very effective surgical option for this condition. Furthermore, BKP is relatively a safe and effective method due to its reduced acrylic cement leakage and greater kyphosis correction. Materials and Methods: A retrospective cohort study was conducted at our hospital for patients who underwent BKP for osteoporotic vertebral fractures in the time frame between January 2020 and December 2022. Ninety-nine patients were included in this study, and they were classified into two groups: in total, 36 patients underwent early BKP intervention (EI) at <4 weeks, and 63 patients underwent late BKP intervention (LI) at ≥4 weeks. We performed a clinical, radiological and statistical comparative evaluation for the both groups with a mean follow-up of one year. Results: Adjacent segmental fractures were more frequently observed in the LI group compared to the EI group (33.3% vs. 13.9%, p = 0.034). There was a significant improvement in postoperative vertebral angles in both groups (p = 0.036). The cement volume injected was 7.42 mL in the EI, compared with 6.3 mL in the LI (p = 0.007). The mean surgery time was shorter in the EI, at 30.2 min, compared with 37.1 min for the LI, presenting a significant difference (p = 0.0004). There was no statistical difference in the pain visual analog scale (VAS) between the two groups (p = 0.711), and there was no statistical difference in cement leakage (p = 0.192). Conclusions/Level of Evidence: Early BKP for OVF treatment may achieve better outcomes and fewer adjacent segmental fractures than delayed intervention. No potential conflict of interest relevant to this article was reported.

Asian Spine Journal (ASJ) Acta Medica Okayama 1976-1902 19 3 2025 More postoperative complications and revision surgery after occipitocervical fusion than after atlantoaxial fusion: a retrospective multicenter cohort study 444 451 EN Koji Uotani Department of Orthopaedic Surgery, Okayama University Hospital Angel Oscar Paz Flores Department of Orthopaedic Surgery, Okayama Rosai Hospital Masato Tanaka Department of Orthopaedic Surgery, Okayama Rosai Hospital Shashank J Ekade Department of Orthopaedic Surgery, Okayama Rosai Hospital Shinya Arataki Department of Orthopaedic Surgery, Okayama Rosai Hospital Tadashi Komatsubara Department of Orthopaedic Surgery, Okayama Rosai Hospital Yoshiaki Oda Department of Orthopaedic Surgery, Okayama University Hospital Kensuke Shinohara Department of Orthopaedic Surgery, Okayama University Hospital Toshifumi Ozaki Department of Orthopaedic Surgery, Okayama University Hospital Study Design: A retrospective multicenter cohort study. Purpose: We sought to determine whether occipitocervical (OC) fusion is followed by more postoperative complications and revision surgery than is atlantoaxial (AA) fusion. We aim to compare postoperative complications and revision surgery associated with OC fusion and AA fusion. Overview of Literature: OC and AA fusion are established techniques for restoring upper cervical stability. However, the outcomes of the two methods have not been compared. Methods: This study included 90 patients who underwent upper spinal fusion surgery for mechanical instability, performed by three surgeons in two hospitals from 2011 to 2023; OC fusion was indicated for irreducible AA subluxation, os odontoideum, and severe upper C1 fracture. Of the patients, 38 (mean age, 58.7 years) underwent OC fusion, and 52 (mean age, 62.8 years) underwent AA fusion. To evaluate surgical outcomes, we documented surgical time, intraoperative blood loss, postoperative complications, and the rate of revision surgery. Radiographs were obtained to identify screw malposition, rod breakage, and nonunion. To compare the outcomes of the two techniques, we used the Mann-Whitney U test for continuous variables and the chi-square or Fisher’s exact test for dichotomous variables. Results: OC fusion took significantly longer (175.4 minutes) than AA fusion (150.7 minutes, p=0.020) and had a higher complication rate (39.5% vs. 11.5%, p<0.0001). The reoperation rate was 23.7% (9/38) after OC fusion and 3.8% (2/52) after AA fusion; the difference was statistically significant (p=0.0073). Average amounts of blood loss were 224 mL during OC fusion and 224 mL during AA fusion; the difference was not significant (p=0.947). Conclusions: Although OC fusion is indispensable for certain conditions, particularly basilar invagination, it entails more risk than dose AA fusion; the choice of technique thus warrants careful consideration. No potential conflict of interest relevant to this article was reported.

Springer Acta Medica Okayama 0340-7004 74 7 2025 Osteosarcoma cell-derived CCL2 facilitates lung metastasis via accumulation of tumor-associated macrophages 193 EN Hiroya Kondo Departments of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hiroshi Tazawa Departments of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Tomohiro Fujiwara Departments of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Aki Yoshida Departments of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Miho Kure Departments of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Koji Demiya Departments of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Nobuhiko Kanaya Departments of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshiaki Hata Departments of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Koji Uotani Departments of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Joe Hasei Departments of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshiyuki Kunisada Departments of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Shunsuke Kagawa Departments of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yusuke Yoshioka Department of Molecular and Cellular Medicine, Tokyo Medical University Toshifumi Ozaki Departments of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshiyoshi Fujiwara Departments of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Osteosarcoma (OS) is the most common malignant tumor of bone in children and adolescents. Although lung metastasis is a major obstacle to improving the prognosis of OS patients, the underlying mechanism of lung metastasis of OS is poorly understood. Tumor-associated macrophages (TAMs) with M2-like characteristics are reportedly associated with lung metastasis and poor prognosis in OS patients. In this study, we investigated the metastasis-associated tumor microenvironment (TME) in orthotopic OS tumor models with non-metastatic and metastatic OS cells. Non-metastatic and metastatic tumor cells derived from mouse OS (Dunn and LM8) and human OS (HOS and 143B) were used to analyze the TME associated with lung metastasis in orthotopic OS tumor models. OS cell-derived secretion factors were identified by cytokine array and enzyme-linked immunosorbent assay (ELISA). Orthotopic tumor models with metastatic LM8 and 143B cells were analyzed to evaluate the therapeutic potential of a neutralizing antibody in the development of primary and metastatic tumors. Metastatic OS cells developed metastatic tumors with infiltration of M2-like TAMs in the lungs. Cytokine array and ELISA demonstrated that metastatic mouse and human OS cells commonly secreted CCL2, which was partially encapsulated in extracellular vesicles. In vivo experiments demonstrated that while primary tumor growth was unaffected, administration of CCL2-neutralizing antibody led to a significant suppression of lung metastasis and infiltration of M2-like TAMs in the lung tissue. Our results suggest that CCL2 plays a crucial role in promoting the lung metastasis of OS cells via accumulation of M2-like TAMs. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 79 1 2025 Could the Trabecular Bone Score Be a Complementary Tool for Evaluating Degenerative Lumbar Vertebrae? 39 45 EN Shinichiro Takao Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Koji Uotani Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Haruo Misawa Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Tomoko Tetsunaga Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kensuke Shinohara Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kentaro Yamane Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yoshiaki Oda Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hironori Tsuji Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yuya Kajiki Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshifumi Ozaki Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Original Article 10.18926/AMO/68360 Evaluating vertebral bone mass and quality in the elderly poses challenges due to degenerative changes. This study aims to elucidate the usefulness of the trabecular bone score (TBS) by examining the relationship between bone mineral density (BMD), TBS, and Hounsfield unit (HU) values. A retrospective analysis of 599 vertebrae from 152 patients (mean age 69.0 years; range 44-89; 74 males and 78 females) undergoing dual-energy X-ray absorptiometry (DXA) and CT scans was conducted. Vertebrae were categorized into three grades based on the degree of degeneration. The TBS was calculated from DXA images, and the HU value was measured by placing a region of interest on an axial image of the vertebral mid-body. One-way analysis of variance and Pearson’s correlation tests were employed to investigate the relationship between BMD and TBS or HU values. While lumbar BMD significantly increased (p<0.01) with degenerative changes, TBS and HU values showed no significant differences. The correlations between lumbar BMD and TBS values, and between BMD and HU values, were stronger without degenerative changes than with degenerative changes. Significantly different HU values were observed between the right and left sides of severely degenerated vertebrae. Severe degenerative changes, particularly those associated with sclerosis, may impact HU values. TBS exhibits greater potential than HU values as a complementary tool. No potential conflict of interest relevant to this article was reported.

Okayama University Medical School Acta Medica Okayama 0386-300X 78 5 2024 Factors Affecting Dynamic Postural Control Ability in Adolescent Idiopathic Scoliosis 357 362 EN Ryoko Yamawaki Division of Physical Medicine and Rehabilitation, Okayama University Yoshiaki Oda Department of Orthopaedic Surgery, Science of Functional Recovery and Reconstruction, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Shuhei Yamane Division of Physical Medicine and Rehabilitation, Okayama University Koji Uotani Department of Orthopaedic Surgery, Okayama University Haruo Misawa Ryusoh Orthopaedic Hospital Yoshimi Katayama Division of Physical Medicine and Rehabilitation, Okayama University Masanori Hamada Division of Physical Medicine and Rehabilitation, Okayama University Toshifumi Ozaki Division of Physical Medicine and Rehabilitation, Okayama University Original Article 10.18926/AMO/67655 Research on postural control in patients with adolescent idiopathic scoliosis (AIS) has focused on static postural control, with few studies assessing dynamic postural control. We aimed to identify factors affecting index of postural stability (IPS), a dynamic postural control parameter, in patients with AIS. The participants comprised 50 female patients with AIS. We measured the IPS using stabilometry to evaluate dynamic postural control ability. We investigated age of the participants, major curve position (thoracic or thoracolumbar/lumbar), Cobb angle, and coronal balance. We then assessed the relationships between stabilometry parameters and other variables. IPS was analyzed with a linear regression model. Coronal balance, major curve position, and age each correlated with dynamic postural control ability. The Cobb angle showed no correlation with any of the parameters. Our results offer new insights into the assessment of postural control in patients with AIS. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 1347-9032 115 11 2024 Identification of ENO-1 positive extracellular vesicles as a circulating biomarker for monitoring of Ewing sarcoma 3660 3671 EN Koji Uotani Department of Orthopedic Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Tomohiro Fujiwara Department of Orthopedic Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Koji Ueda Cancer Precision Medicine Center, Japanese Foundation for Cancer Research Aki Yoshida Department of Orthopedic Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Shintaro Iwata Department of Musculoskeletal Oncology, National Cancer Center Hospital Takuya Morita Department of Orthopedic Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Masahiro Kiyono Department of Orthopedic Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Toshiyuki Kunisada Department of Medical Materials for Musculoskeletal Reconstruction, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Ken Takeda Department of Intelligent Orthopedic System, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Joe Hasei Department of Orthopedic Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Yusuke Yoshioka Department of Molecular and Cellular Medicine, Institute of Medical Science, Tokyo Medical University Takahiro Ochiya Department of Molecular and Cellular Medicine, Institute of Medical Science, Tokyo Medical University Toshifumi Ozaki Department of Orthopedic Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences The lack of circulating biomarkers for tumor monitoring is a major problem in Ewing sarcoma management. The development of methods for accurate tumor monitoring is required, considering the high recurrence rate of drug- resistant Ewing sarcoma. Here, we describe a sensitive analytical technique for tumor monitoring of Ewing sarcoma by detecting circulating extracellular vesicles secreted from Ewing sarcoma cells. Proteomic analysis of Ewing sarcoma cell-derived extracellular vesicles identi-fied 564 proteins prominently observed in extracellular vesicles from three Ewing sarcoma cell lines. Among these, CD99, SLC1A5, and ENO-1 were identified on extra-cellular vesicles purified from sera of patients with Ewing sarcoma before treatment but not on extracellular vesicles from those after treatment and healthy individuals. Notably, not only Ewing sarcoma-derived extracellular vesicles but also Ewing sar-coma cells demonstrated proteomic expression of CD99 and ENO-1 on their surface membranes. ENO-1(+)CD6(3+) extracellular vesicle detection was reduced after tumor resection while both CD99+CD63+ and ENO-1(+)CD6(3+) extracellular vesicles were detected in serum from Ewing sarcoma- bearing mice. Finally, the accuracy of liquid biopsy targeting these candidates was assessed using extracellular vesicles from the sera of patients with Ewing sarcoma. Elevated ENO-1+CD81+ extracellular vesicles in the serum of patients before treatments distinguished patients with Ewing sarcoma from healthy individuals with an area under the curve value of 0.92 (P< 0.001) and reflected the tumor burden in patients with Ewing sarcoma during multidisciplinary treatments. Collectively, circulating ENO-1(+)CD81(+) extracellular vesicle detection could represent a novel tool for tumor monitoring of Ewing sarcoma. No potential conflict of interest relevant to this article was reported.

Lippincott, Williams & Wilkins Acta Medica Okayama 0025-7974 103 32 2024 Insomnia among patients with chronic pain A retrospective study e39113 EN Masataka Ueda Department of Orthopaedic Surgery, Science of Functional Recovery and Reconstruction, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Tomoko Tetsunaga Department of Orthopaedic Surgery, Okayama University Tomonori Tetsunaga Department of Musculoskeletal Health Promotion, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Keiichiro Nishida Division of Chronic Pain Medicine and Division of Comprehensive Rheumatology, Locomotive Pain Center, Okayama University Hospital Ryo Takatori Department of Orthopaedic Surgery, Science of Functional Recovery and Reconstruction, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hisakazu Shitozawa Department of Orthopaedic Surgery, Science of Functional Recovery and Reconstruction, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Koji Uotani Department of Orthopaedic Surgery, Okayama University Kennsuke Shinohara Department of Sports Medicine, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yoshiaki Oda Department of Orthopaedic Surgery, Science of Functional Recovery and Reconstruction, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Toshifumi Ozaki Department of Orthopaedic Surgery, Science of Functional Recovery and Reconstruction, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Insomnia can coexist with chronic pain and is a major cause of rapidly increasing medical expenses. However, insomnia has not been fully evaluated in patients with chronic pain. This retrospective study aimed to identify the risk factors for insomnia in patients with chronic non-cancer pain. A total of 301 patients with chronic non-cancer pain were enrolled. Patients with the Athens insomnia scale scores >= 6 and < 6 were classified into insomnia (+) and insomnia (-) groups, respectively. All patients completed self-report questionnaires as part of their chronic pain treatment approach. Univariate and multivariate analyses were performed to predict insomnia. We found that 219 of 301 (72.8%) patients met the AIS criteria for insomnia. Significant differences were depicted between patients with and without insomnia in terms of body mass index, numeric rating scale, pain catastrophizing scale, hospital anxiety, and depression scale (HADS), pain disability assessment scale, EuroQol 5 dimension (EQ5D), and pain self-efficacy questionnaire. Multiple regression analysis identified the numeric rating scale, HADS, and EQ5D scores as factors related to insomnia in patients with chronic non-cancer pain. Anxiety, depression, and disability were associated with a greater tendency toward insomnia. HADS and EQ5D scores are useful screening tools for preventing insomnia in patients with chronic non-cancer pain. No potential conflict of interest relevant to this article was reported.

Public Library of Science Acta Medica Okayama 1932-6203 19 2 2024 Fluorescence-guided assessment of bone and soft-tissue sarcomas for predicting the efficacy of telomerase-specific oncolytic adenovirus e0298292 EN Koji Uotani Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hiroshi Tazawa Center for Innovative Clinical Medicine, Okayama University Hospital Joe Hasei Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Tomohiro Fujiwara Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Aki Yoshida Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yasuaki Yamakawa Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshinori Omori Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Kazuhisa Sugiu Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Tadashi Komatsubara Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hiroya Kondo Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Takuya Morita Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masahiro Kiyono Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Suguru Yokoo Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshiaki Hata Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshiyuki Kunisada Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Ken Takeda Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Yasuo Urata Oncolys BioPharma, Inc. Toshiyoshi Fujiwara Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Toshifumi Ozaki Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Bone and soft-tissue sarcomas are rare malignancies with histological diversity and tumor heterogeneity, leading to the lack of a common molecular target. Telomerase is a key enzyme for keeping the telomere length and human telomerase reverse transcriptase (hTERT) expression is often activated in most human cancers, including bone and soft-tissue sarcomas. For targeting of telomerase-positive tumor cells, we developed OBP-301, a telomerase-specific replication-competent oncolytic adenovirus, in which the hTERT promoter regulates adenoviral E1 gene for tumor-specific viral replication. In this study, we present the diagnostic potential of green fluorescent protein (GFP)-expressing oncolytic adenovirus OBP-401 for assessing virotherapy sensitivity using bone and soft-tissue sarcomas. OBP-401-mediated GFP expression was significantly associated with the therapeutic efficacy of OBP-401 in human bone and soft-tissue sarcomas. In the tumor specimens from 68 patients, malignant and intermediate tumors demonstrated significantly higher expression levels of coxsackie and adenovirus receptor (CAR) and hTERT than benign tumors. OBP-401-mediated GFP expression was significantly increased in malignant and intermediate tumors with high expression levels of CAR and hTERT between 24 and 48 h after infection. Our results suggest that the OBP-401-based GFP expression system is a useful tool for predicting the therapeutic efficacy of oncolytic virotherapy on bone and soft-tissue sarcomas. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1010-660X 58 5 2022 Mechanical Study of Various Pedicle Screw Systems including Percutaneous Pedicle Screw in Trauma Treatment 565 EN Yoshiaki Oda Department of Orthopaedic Surgery, Okayama University Hospital Tomoyuki Takigawa Department of Orthopaedic Surgery, Kobe Red Cross Hospital Yasuo Ito Department of Orthopaedic Surgery, Kobe Red Cross Hospital Haruo Misawa Department of Orthopaedic Surgery, Okayama University Hospital Tomoko Tetsunaga Department of Orthopaedic Surgery, Okayama University Hospital Koji Uotani Department of Orthopaedic Surgery, Okayama University Hospital Toshifumi Ozaki Department of Orthopaedic Surgery, Dentistry, and Pharmaceutical Sciences, Graduate School of Medicine, Okayama University Background and Objectives: Spine surgery using a percutaneous pedicle screw placement (PPSP) is widely implemented for spinal trauma. However, percutaneous systems have been reported to have weak screw-rod connections. In this study, conventional open and percutaneous systems were biomechanically evaluated and compared. Material and Methods: The experiments were performed in two stages: the first stage was a break test, whereas the second stage was a fatigue test. Four systems were used for the experiments. System 1 was intended for conventional open surgery (titanium rod with a 6.0 mm diameter, using a clamp connecting mechanism). System 2 was a percutaneous pedicle screw (PPS) system for trauma (titanium alloy rod with a 6.0 mm diameter, using ball ring connections). System 3 was a PPS system for trauma (cobalt-chromium alloy rod with a 6.0 mm diameter, using sagittal adjusting screw connections). System 4 was a general-purpose PPS system (titanium alloy rod with a 5.5 mm diameter, using a mechanism where the adapter in the head holds down the screw). Results: Stiffness values of 54.8 N/mm, 43.1 N/mm, 90.9 N/mm, and 39.3 N/mm were reported for systems 1, 2, 3, and 4, respectively. The average number of load cycles in the fatigue test was 134,393, 40,980, 1,550,389, and 147,724 for systems 1 to 4, respectively. At the end of the test, the displacements were 0.2 mm, 16.9 mm, 1.2 mm, and 8.6 mm, respectively. System 1, with a locking mechanism, showed the least displacement at the end of the test. Conclusion: A few PPS systems showed better results in terms on stiffness and life than the open system. The experiments showed that mechanical strength varies depending on the spinal implant. The experiments conducted are essential and significant to provide the mechanical strength required for surgical reconstruction. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1010-660X 58 5 2022 Long-Term Results of Posterior Vertebral Column Resection for Severe Thoracolumbar Kyphosis with Achondroplastic Patients: A Case Series 605 EN Masato Tanaka Department of Orthopaedic Surgery, Okayama University Hospital Tsang-Tung Chan Department of Orthopaedic Surgery, Okayama University Hospital Haruo Misawa Department of Orthopaedic Surgery, Okayama University Hospital Koji Uotani Department of Orthopaedic Surgery, Okayama University Hospital Shinaya Arataki Department of Orthopaedic Surgery, Okayama University Hospital Tomoyuki Takigawa Department of Orthopaedic Surgery, Okayama University Hospital Tetsuro Mazaki Department of Orthopaedic Surgery, Okayama University Hospital Yoshihisa Sugimoto Department of Orthopaedic Surgery, Okayama University Hospital Background and Objectives: Thoracolumbar kyphosis is one of the most frequent skeletal manifestations in patients with achondroplasia. Few papers have been published on the surgical treatment of this condition, especially in skeletally mature patients. With this study, we presented a retrospective case series of long-term surgical results for achondroplastic patients with severe thoracolumbar kyphosis. This study was conducted to evaluate the outcome of surgical treatment for thoracolumbar kyphosis in patients associated with achondroplasia presenting with paraparesis. Materials and Methods: Three patients with achondroplasia who developed neurologic deficits due to severe thoracolumbar kyphosis and underwent surgical treatment were evaluated (mean age 22.3 years; mean follow-up 9.3 years). All patients were treated with posterior vertebral column resection (p-VCR) of hypoplastic apical vertebrae with a cage and segmental instrumentation. Neurologic outcomes (JOA scores), correction of kyphosis, and operative complications were assessed. Results: All patients had back pain, neurological deficits, and urinary disturbance before surgery. The average preoperative JOA score was 8.3/11 points, which was improved to 10.7/11 points at the final follow-up (mean recovery rate 83%). All patients obtained neurologic improvement after surgery. The mean preoperative kyphotic angle was 117 degrees (range 103 degrees-126 degrees). The postoperative angles averaged 37 degrees (range 14 degrees-57 degrees), resulting in a mean correction rate of 67%. All patients had postoperative complications such as rod breakage and/or surgical site infection. Conclusions: The long-term results of p-VCR were acceptable for treating thoracolumbar kyphosis in patients with achondroplasia. To perform this p-VCR safely, spinal navigation and neuromonitoring are inevitable when resecting non anatomical fused vertebrae and ensuring correct pedicle screw insertion. However, surgical complications such as rod breakage and surgical site infection may occur at a high rate, making informed consent very important when surgery is indicated. No potential conflict of interest relevant to this article was reported.

Elsevier Inc. Acta Medica Okayama 18788750 156 2021 Comparative Study of Bilateral Dual Sacral-Alar-Iliac Screws versus Bilateral Single Sacral-Alar-Iliac Screw for Adult Spine Deformities e300 e306 EN Koji Uotani Department of Orthopaedic surgery, Okayama Rosai Hospital Masato Tanaka Department of Orthopaedic surgery, Okayama Rosai Hospital Sumeet Sonawane Department of Orthopaedic surgery, Okayama Rosai Hospital Sameer Ruparel Department of Orthopaedic surgery, Okayama Rosai Hospital Yoshihiro Fujiwara Department of Orthopaedic surgery, Okayama Rosai Hospital Shinya Arataki Department of Orthopaedic surgery, Okayama Rosai Hospital Taro Yamauchi Department of Orthopaedic surgery, Okayama Rosai Hospital Haruo Misawa Department of Orthopaedic surgery, Okayama University Hospital Objective To evaluate the feasibility of O-arm navigation of bilateral dual sacral-alar-iliac (SAI) screws compared with conventional bilateral single SAI and S1 pedicle screws for pelvic anchors in cases of adult spinal deformity. Methods This retrospective, comparative study included 39 patients who underwent corrective fusion using SAI screws from T10 to the pelvis. Patients were divided into 2 groups according to the number of SAI screws placed during adult spinal deformity surgery: single SAI screw (group S, 17 cases) and dual SAI screws (group D, 22 cases). The incidence of rod breakage, proximal junctional kyphosis, screw loosening, reoperation, and global alignment in each group was estimated. Postoperative patient-reported outcomes were measured using the Oswestry Disability Index, Japanese Orthopaedic Association Back Pain Evaluation Questionnaire, and visual analog scale. Results The incidence of SAI screw loosening was significantly lower in group D than in group S (23% vs. 65%, P = 0.011). The rod breakage incidence was 0% and 12% in groups D and S, respectively (P = 0.17). There were no significant differences in the postoperative global alignment and clinical outcomes between the 2 groups. Conclusions Dual SAI screws were associated with a significantly reduced incidence of screw loosening compared with single SAI screws. The bilateral dual SAI screws technique for pelvic anchors is feasible for the treatment of patients with adult spinal deformity. No potential conflict of interest relevant to this article was reported.