TSTakanori Saito

Takanori Saito

*This is an algorithmically generated author record based on publicly available information.

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Takanori Saito has a total of 62 co-authors. Here are the top co-authors by number of shared publications:


Latest Publications

  • Proximal and distal junctional failures after a short-segment minimally invasive surgery combination that incorporates anterior column realignment (ACR) for adult spinal deformity

    by Yoichi Tani, Takahiro Tanaka, Nobuhiro Naka, Naoto Ono, Koki Kawashima, Masaaki Paku, Masayuki Ishihara, Takashi Adachi, Shinichirou Taniguchi, Muneharu Ando, et al.


  • Open Access

    A Pilot Three-Dimensional Evaluation of Acetabular Bony Coverage After Modified Spitzy Shelf Acetabuloplasty

    by Fumito Kobayashi, Takehito Hananouchi, Kenichi Oe, Shohei Sogawa, Tomohisa Nakamura, Takanori Saito

    Modified Spitzy shelf acetabuloplasty is a joint-preserving surgical procedure for acetabular dysplasia that aims to enhance bony coverage of the hip joint. Although prior studies have primarily relied on two-dimensional (2D) radiographic evaluations, comprehensive three-dimensional (3D) assessments remain limited. The purpose of this retrospective study was to evaluate changes quantitatively in acetabular coverage following modified Spitzy shelf acetabuloplasty using 3D models reconstructed from computed tomography (CT) images. We retrospectively analyzed 11 hips in 11 patients who underwent staged bilateral modified Spitzy shelf acetabuloplasty. Preoperative and postoperative CT data were used to construct 3D pelvic models, which were registered using anatomical landmarks. Bone graft dimensions, insertion angle, and placement location were evaluated. Acetabular sector angles (ASA), representing circumferential coverage of the femoral head, were measured at 15° intervals on the functional pelvic plane and the anterior pelvic plane. The mean bone graft dimensions were 26.3 ± 3 mm (anteroposterior length) and 12.7 ± 2.7 mm (mediolateral length), providing coverage of 49.5° ± 9.1°. Postoperative ASA increased significantly from 34.5° to 60° on the functional pelvic plane and from 0° to 45° on the anterior pelvic plane (both p < 0.05). 3D analysis demonstrated that modified Spitzy shelf acetabuloplasty effectively enhanced anterosuperior acetabular bony coverage. Although this is a report of a few cases (11 hips), the above findings highlight the value of 3D evaluation in identifying postoperative changes that may not be detected using conventional 2D assessments. Also, further research analyzing the three-dimensional bone graft model revealed in this study may help inform the development of a more ideal biomimetic approach, not only in terms of shape but also function.

  • Type 2 statin use increased perioperative blood loss in primary reverse total shoulder arthroplasty

    by Kotaro Yamakado, Kunihiro Suzuki, Hirofumi Katsutani, Hideaki Nagamoto, Junji Inoue, Hayato Satake, Tsukasa Kumai, Takanori Saito

    Purpose Statins (hydroxyl-methylglutaryl-coenzyme-A reductase inhibitors) are commonly prescribed for managing hypercholesterolemia. Besides lowering cholesterol, statins have been reported to have anticoagulant and antiplatelet effects. This study aimed to analyze postoperative blood loss by standardizing the surgical procedure for reverse total shoulder arthroplasty and evaluate the effect of statin use on bleeding. Methods A retrospective review of prospectively collected primary RSA cases was conducted, identifying the use and types of statins: type 1 (naturally derived) and type 2 (synthetic). Those taking anticoagulants and antiplatelet medications were excluded. Multiple regression models were utilized to identify the predictors of estimated blood loss. Blood loss was calculated using preoperative and third-day postoperative hematocrit values. Preoperative factors, surgery-related factors (surgical time, stem length), and the administration of tranexamic acid were collected and analyzed. Results A total of 243 cases were included. Statins were administered in 62 cases (26%). The estimated blood loss was 826 ± 332 ml in the statin-use group and 738 ± 308 ml in the statin-nonuse group. The regression analysis identified type 2 statin use, male sex, tranexamic acid administration, and ASA classification as statistically significant predictors of total blood loss (P < .05). Specifically, type 2 statin use was associated with an estimated increase in bleeding volume of 148 mL (95% confidence interval: 54 to 242 mL). Conclusions The current study showed that type 2 statin use was a significant predictor of increased perioperative blood loss. However, the anticipated increase in bleeding was not significant, and whether the risk of bleeding outweighs the benefits of statin use should be decided on an individual basis.


  • Open Access

    Risk Factor Analysis of Mechanical Complications in Surgical Treatment of Thoracolumbar Deformity with Osteoporotic Vertebral Fracture

    by Yoshihisa Kotani, Takahiro Tanaka, Atsushi Ikeura, Takanori Saito

    Objective: Adult spinal deformity (ASD) with osteoporotic vertebral fractures (OVF) often requires vertebral body resection and replacement. However, postoperative mechanical complications (MC) have been unsolved issues. This study retrospectively investigated the risk of MC following anterior-posterior spinal fusion (APF) with vertebral body resection and replacement for OVF with ASD. Methods: Among 91 cases undergoing APF with vertebral body resection and replacement, 43 cases met the deformity criteria. The mean age was 74.2 years, and the mean number of fused segments was 5.7. Pre and postoperative spinal alignments were measured, and the risk of MC occurrence, including PJK, DJK, and cage sinking, was determined through multivariate analysis. The AUC and cutoff values were calculated through ROC analysis. Results: The incidence of MC, PJK, and DJK were 28%, 12%, and 14%, respectively. Multivariate analysis for MC revealed postoperative PI-LL and operative time (cutoff: 40.5 degrees, 238 min) as significant risk factors, while postoperative PI-LL was a significant risk factor for PJK (cutoff: 42.4 degrees). Evaluation considering only thoracolumbar level showed postoperative local kyphosis as a significant MC risk factor (cutoff: 11 degrees). There was a positive correlation between operative time and preoperative local kyphosis, with a cutoff value of 238 min being equivalent to 21 degrees. Conclusion: The postoperative mismatch over 40 degrees and preoperative local kyphosis over 21 degrees were considered as a high risk for MCs. The postoperative kyphosis of 11 degrees was the risk factor of MC in the thoracolumbar level. The meticulous preoperative assessment, including local and global alignment, and local flexibility as well as detailed surgical planning of fixation range and the requirement of osteotomy, are crucial.


  • Open Access

    Can We Rely on Prophylactic Two-Level Vertebral Cement Augmentation in Long-Segment Adult Spinal Deformity Surgery to Reduce the Incidence of Proximal Junctional Complications?

    by Yoichi Tani, Nobuhiro Naka, Naoto Ono, Koki Kawashima, Masaaki Paku, Masayuki Ishihara, Takashi Adachi, Muneharu Ando, Shinichirou Taniguchi, Takanori Saito

    Background and Objectives: Proximal junctional kyphosis (PJK) and failure (PJF), the most prevalent complications following long-segment thoracolumbar fusions for adult spinal deformity (ASD), remain lacking in defined preventive measures. We studied whether one of the previously reported strategies with successful results—a prophylactic augmentation of the uppermost instrumented vertebra (UIV) and supra-adjacent vertebra to the UIV (UIV + 1) with polymethylmethacrylate (PMMA)—could also serve as a preventive measure of PJK/PJF in minimally invasive surgery (MIS). Materials and Methods: The study included 29 ASD patients who underwent a combination of minimally invasive lateral lumbar interbody fusion (MIS-LLIF) at L1-2 through L4-5, all-pedicle-screw instrumentation from the lower thoracic spine to the sacrum, S2-alar-iliac fixation, and two-level balloon-assisted PMMA vertebroplasty at the UIV and UIV + 1. Results: With a minimum 3-year follow-up, non-PJK/PJF group accounted for fifteen patients (52%), PJK for eight patients (28%), and PJF requiring surgical revision for six patients (21%). We had a total of seven patients with proximal junctional fracture, even though no patients showed implant/bone interface failure with screw pullout, probably through the effect of PMMA. In contrast to the PJK cohort, six PJF patients all had varying degrees of neurologic deficits from modified Frankel grade C to D3, which recovered to grades D3 and to grade D2 in three patients each, after a revision operation of proximal extension of instrumented fusion with or without neural decompression. None of the possible demographic and radiologic risk factors showed statistical differences between the non-PJK/PJF, PJK, and PJF groups. Conclusions: Compared with the traditional open surgical approach used in the previous studies with a positive result for the prophylactic two-level cement augmentation, the MIS procedures with substantial benefits to patients in terms of less access-related morbidity and less blood loss also provide a greater segmental stability, which, however, may have a negative effect on the development of PJK/PJF.


  • Open Access

    The modified Spitzy shelf acetabuloplasty for the dysplastic hip

    by Kenichi Oe, Hirokazu Iida, Yosuke Otsuki, Fumito Kobayashi, Shohei Sogawa, Tomohisa Nakamura, Takanori Saito

    The modified Spitzy shelf acetabuloplasty for the dysplastic hip


  • An atypical periprosthetic fracture in collarless, polished, tapered, cemented stems of total hip arthroplasty: A report of five SC-stem cases and literature review

    by Kenichi Oe, Hirokazu Iida, Masayuki Hirata, Hiroshi Kawamura, Narumi Ueda, Tomohisa Nakamura, Naofumi Okamoto, Takanori Saito


  • Open Access

    A New Total Knee Arthroplasty Technique for Valgus Knees that preserves the deep layer of the medial collateral ligament

    by Hiroshi Ohno, Minoru Murata, Tomohiro Kamo, Hideo Sugimoto, Takanori Saito

    Objective: The aim of this study was to assess the outcomes and complications, such as tibiofemoral instability and recurrence of valgus deformity, of total knee arthroplasty for valgus knees with a new technique preserving the deep layer of the medial collateral ligament. Methods: In this study 33 (4 male and 29 female) patients, and a total of 36 (26 knees with osteoarthritis and 10 with rheumatoid arthritis) knees with a standing femorotibial angle (FTA) of <170° were included. Posterior Stabilized (PS) implants were used in 34 knees, rotating hinged knee implants were used in 2 knees. The procedures were carried out by a single surgeon protecting the deep layer of the medial collateral ligament. The patients’ average age at the time of the operation was 67.6 ± 12 years, and the average follow-up period was 9.0 ± 3 years (range, 4-15 years). The Japanese Orthopaedic Association (JOA) knee score, range of motion (ROM) (extension/flexion; measured in degrees), FTA (measured in degrees) and complications were investigated. Results: The Japanese Orthopaedic Association knee score significantly improved from an average of 51 ± 12 points before the operation to 86 ± 9 points after the operation (P <0.001). The extension ROM and flexion ROM improved from, -13 ± 13° to a postoperative average of -2 ± 4°, and 115 ± 25° to a postoperative average of 125 ± 18° respectively (P <0.001). The standing FTA significantly improved from 158 ± 9° to an average of 173 ± 2° after the operation (P <0.001). Thirty-four knees with severe valgus deformity were operated on using pos- terior stabilised implants, while only two knees required constrained implants. During follow-up, no complications, such as tibiofemoral instability, recurrence of valgus deformity, patellar necrosis, deep infection, wound problems, or peroneal nerve paralysis were observed. Conclusion: This study has shown us that after performing TKA while preserving the d-MCL for valgus knee deformity good clinical results were obtained and no complications were observed. Level of Evidence: Level IV, Therapeutic Study Cite this article as: Ohno H, Murata M, Kamo T, Sugimoto H, Saito T. A new total knee arthroplasty technique for valgus knees that preserves the deep layer of the medial collateral ligament. Acta Orthop Traumatol Turc 2022;56(3):205-209.


  • Open Access

    A New Treatment Algorithm That Incorporates Minimally Invasive Surgery for Pyogenic Spondylodiscitis in the Thoracic and Lumbar Spines: The Results of Its Clinical Application to a Series of 34 Patients

    by Yoichi Tani, Takanori Saito, Shinichiro Taniguchi, Masayuki Ishihara, Masaaki Paku, Takashi Adachi, Muneharu Ando, Yoshihisa Kotani

    Background and Objectives: Spinal minimally invasive surgery (MIS) experts at the university hospital worked as a team to develop a new treatment algorithm for pyogenic spondylodiscitis in lumbar and thoracic spines. They modified a flow chart introduced for this condition in a pre-MIS era to incorporate MIS techniques based on their extensive experiences accumulated over the years, both in MIS for degenerative lumbar diseases and in the treatment of spine infections. The MIS procedures incorporated in this algorithm consisted of percutaneous pedicle screw (PPS)–rod fixation and transpsoas lateral lumbar interbody fusion (LLIF). The current study analyzed a series of 34 patients treated with prospective selection of the methods according to this new algorithm. Materials and Methods: The algorithm first divided the patients into those who had escaped complicated disease conditions, such as neurologic impairment, extensive bone destruction, and the need to be mobilized without delay (Group 1) (19), and those with complicated pyogenic spondylodiscitis (Group 2) (15). Group 1 had image-guided needle biopsy followed by conservative treatment alone with antibiotics and a spinal brace (12) (Group 1-A) or a subsequent addition of non-fused PPS–rod fixation (7) (Group 1-B). Group 2 underwent an immediate single-stage MIS with non-fused PPS–rod fixation followed by posterior exposure for decompression and debridement through a small midline incision (12) (Group 2-A) or an additional LLIF procedure after an interval of 3 weeks (3) (Group 2-B). Results: All patients, except four, who either died from causes unrelated to the spondylodiscitis (2) or became lost to follow up (2), were cured of infection with normalized CRP at an average follow up of 606 days (105–1522 days). A solid interbody fusion occurred at the affected vertebrae in 15 patients (50%). Of the patients in Group 2, all but two regained a nearly normal function. Despite concerns about non-fused PPS–rod instrumentation, only seven patients (21%) required implant removal or replacement. Conclusions: Non-fused PPS–rod placements into infection-free vertebrae alone or in combination with posterior debridement through a small incision worked effectively in providing local stabilization without contamination of the metal implant from the infected tissue. MIS LLIF allowed for direct access to the infected focus for bone grafting in cases of extensive vertebral body destruction.


  • Open Access

    Efficacy of Minimally Invasive Trans-Sacral Canal Plasty between Patients with and without Failed Back Surgery Syndrome

    by Haruki Funao, Kimiaki Yokosuka, Junichi Ukai, Kazuo Nakanishi, Masaaki Paku, Takashi Tomita, Masahiro Hoshino, Takanori Saito, Ken Ishii, Koji Sato

    Background and Objectives: Clinicians are required to manage a growing number of elderly patients with several medical comorbidities, and invasive surgical treatments are sometimes not advisable for these patients. The aim of this study was to evaluate the efficacy of minimally invasive intraspinal canal treatment, trans-sacral canal plasty (TSCP), for patients with and without failed back surgery syndrome (FBSS). Materials and Methods: A multicenter analysis was conducted. TSCP was performed in patients with chronic low back pain and leg pain due to lumbar spinal disorders. An adhesiolysis by TSCP was carried out, then a mixture of steroid and local anesthesia was injected. Visual Analog Scales (VAS) for low back pain and leg pain, and complications were evaluated. Results: A total of 271 patients with a minimum 6-month follow-up were enrolled. There were 80 patients who had a history of previous lumbar spinal surgery (F group), and 191 patients without previous lumbar spinal surgery (N group). There were no significant differences in sex and age between the two groups. VAS scores for low back pain (N group/F group) preoperatively, immediately postoperatively, and 1 month, 3 months and 6 months postoperatively, were 51/52 mm, 24/26 mm, 33/34 mm, 30/36 mm, and 30/36 mm, respectively. VAS scores for leg pain were 69/67 mm, 28/27 mm, 39/41 mm, 36/43 mm, and 32/40 mm, respectively. Both VAS scores for low back pain and leg pain were significantly decreased from baseline to final follow-up in both groups (p < 0.01). However, VAS scores for leg pain at 3 months and 6 months postoperatively were significantly higher in F group (p < 0.05). There were three catheter breakages (2/3 in F group), and one dural tear in F group. Conclusions: TSCP significantly reduced both VAS scores for low back and leg pain in patients with and without FBSS. However, co-existence of intractable epidural adhesion might be associated with less improvement in FBSS.