Elsevier (Singapore) Pte Ltd. Acta Medica Okayama 2214-6873 32 2023 Accuracy of the newly developed Zimmer Biomet Root Aiming guide in tibial tunnel creation compared with that of conventional guides 1 6 EN Takaaki Hiranaka Department of Orthopaedic Surgery, Okayama University Hospital Takayuki Furumatsu Department of Orthopaedic Surgery, Okayama University Hospital Yuki Okazaki Department of Orthopaedic Surgery, Okayama University Hospital Keisuke Kintaka Department of Orthopaedic Surgery, Okayama University Hospital Naohiro Higashihara Department of Orthopaedic Surgery, Okayama University Hospital Masanori Tamura Department of Orthopaedic Surgery, Okayama University Hospital Eiji Nakata Department of Orthopaedic Surgery, Okayama University Hospital Toshifumi Ozaki Department of Orthopaedic Surgery, Okayama University Hospital Background/objective: Accurate tibial tunnel creation is crucial for successful transtibial pullout repair of medial meniscus (MM) posterior root tears (MMPRTs). This study aimed to evaluate the accuracy of the newly developed Zimmer Biomet Root Aiming (ZeBRA) guide for transtibial pullout repair of MMPRTs.Methods: This study included 50 patients who underwent transtibial pullout repair using the Unicorn Meniscal Root (UMR) (n = 25) and ZeBRA (n = 25) guides. The expected anatomic centre (AC) and tibial tunnel centre (TC) were assessed using three-dimensional postoperative computed tomography (CT) images. The expected AC was defined as the centre of the circle tangent to the triangular footprint of the MM posterior root. The expected AC and TC on the tibial surface were assessed using the percentage-based posterolateral location on the tibial surface. The absolute distance between the AC and TC (mm) was evaluated. Results: The mean AC location was 76.1% +/- 3.1% posterior and 40.8% +/- 2.1% lateral, whereas the mean TC location was 76.7% +/- 5.3% posterior and 37.2% +/- 3.6% lateral using the UMR guide and 75.8% +/- 3.1% posterior and 36.5% +/- 2.4% lateral using the ZeBRA guide. No significant difference was observed in the absolute distance between the UMR and ZeBRA guides (3.9 +/- 1.4 and 3.8 +/- 1.3 mm, respectively; p = 0.617). Conclusions: The newly developed ZeBRA guide allows accurate tibial tunnel creation, and its accuracy is comparable to that of the conventional UMR guide. Tibial tunnels were created at optimal positions using both guides, and the choice of the guide would depend on the surgeon's preference. No potential conflict of interest relevant to this article was reported.

Elsevier B.V. Acta Medica Okayama 09492658 2021 A newly-developed guide can create tibial tunnel at an optimal position during medial meniscus posterior root repairs EN Takaaki Hiranaka Department of Orthopaedic Surgery, Okayama University Hospital Takayuki Furumatsu Department of Orthopaedic Surgery, Okayama University Hospital Yuki Okazaki Department of Orthopaedic Surgery, Okayama University Hospital Keisuke Kintaka Department of Orthopaedic Surgery, Okayama University Hospital Tadashi Yamawaki Department of Orthopaedic Surgery, Kosei Hospital Toshifumi Ozaki Department of Orthopaedic Surgery, Okayama University Hospital Background During transtibial pullout repair of medial meniscus (MM) posterior root tears (MMPRTs), accurate tibial tunnel creation within the anatomic MM posterior root attachment seems critical. This study aimed to evaluate the tibial tunnel position created by a newly-developed Precision guide during pullout repair of MMPRTs. Methods In 40 patients who underwent transtibial pullout repairs, the tibial tunnel was created using the Unicorn Meniscal Root (UMR) (n = 20) or Precision guide (n = 20). Three-dimensional computed tomography images of the tibial surface were evaluated postoperatively, using Tsukada's measurement method. The expected anatomic center of the MM posterior root attachment was defined as the center of three tangential lines corresponding to anatomic bony landmarks. The expected anatomic center (AC) and the tibial tunnel center (TC) were evaluated using the percentage-based posterolateral location on the tibial surface. The difference in the mediolateral and anteroposterior percentage distance between the AC and TC was calculated, as was the absolute distance between the AC and TC. Results The mean AC was located 77.4% posterior and 40.1% lateral. The mean TC was similar in the UMR and Precision guide groups. There was no significant difference in the mediolateral percentage distance (UMR 3.9% vs. Precision 3.6%, p = 0.405), but a significant difference was observed in the anteroposterior percentage distance (UMR 3.5% vs. Precision 2.6%, p = 0.031). The mean absolute distance between the AC and TC was 3.9 mm and 3.5 mm (UMR and Precision guide groups, respectively) (p = 0.364). Conclusions The new Precision guide can create tibial tunnel in an optimal and stable position during pullout repair of MMPRTs. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 1877-0568 107 2 2021 Intraarticular lengths of double-bundle grafts can change during knee flexion: Intraoperative measurements in anatomic anterior cruciate ligament reconstructions 102816 EN Takayuki Furumatsu Department of Orthopaedic Surgery, Okayama University Hospital Takaaki Hiranaka Department of Orthopaedic Surgery, Okayama University Hospital Yuya Kodama Department of Orthopaedic Surgery, Okayama University Hospital Yusuke Kamatsuki Department of Orthopaedic Surgery, Okayama University Hospital Yuki Okazaki Department of Orthopaedic Surgery, Okayama University Hospital Tadashi Yamawaki Department of Orthopaedic Surgery, Okayama University Hospital Hirosuke Endo Department of Orthopaedic Surgery, Okayama University Hospital Toshifumi Ozaki Department of Orthopaedic Surgery, Okayama University Hospital Background: The lengths of the anteromedial bundle (AMB) and posterolateral bundle (PLB) change during knee motion during double-bundle anterior cruciate ligament (ACL) reconstruction. However, the actual intraarticular graft length would be affected by the bone tunnel position and tunnel creation angle during ACL reconstruction. The aim of this study was to investigate the intraarticular length change of the AMB and PLB in patients who underwent anatomic double-bundle ACL reconstruction. Hypothesis: We hypothesized that the PLB would show a more dynamic length change pattern than the AMB during knee flexion at ACL reconstruction. Methods: Thirty-two patients (16 men and 16 women) who had isolated ACL injuries with intact menisci were investigated. Anatomic double-bundle ACL reconstructions were performed using semitendinosus tendon autografts at a mean age of 30.6 years. The graft and tunnel lengths were measured intraoperatively. Intraarticular graft lengths and length changes were calculated at 0˚ and 90˚ of knee flexion during ACL reconstruction. Intraoperative data were collected prospectively, and analyses were performed retrospectively. Results: The intraarticular length of the AMB at 0˚ of knee flexion was 28.1 ± 5.5 mm. At 90˚ of knee flexion, the AMB intraarticular length decreased to 25.6 ± 4.8 mm. The intraarticular length of the PLB decreased to 17.7 ± 4.6 mm at 90˚ of knee flexion compared to 22.0 ± 4.2 mm at 0˚ of knee flexion. Changes in the intraarticular graft length during knee flexion were detected more in the PLB (4.1 mm) than in the AMB (2.0 mm, P = 0.01). Discussion: This study demonstrated that the intraarticular length change of the PLB during knee motion was larger than that of the AMB in anatomic double-bundle ACL reconstructions with semitendinosus tendon autografts and suspensory femoral fixation devices. No potential conflict of interest relevant to this article was reported.

Elsevier Masson SAS Acta Medica Okayama 18770517 107 2 2021 Les longueurs intra-articulaires des greffons à double faisceau peuvent changer pendant la flexion du genou : mesures peropératoires lors de reconstructions anatomiques du ligament croisé antérieur 244 245 EN Takayuki Furumatsu Department of Orthopaedic Surgery, Okayama University Hospital Takaaki Hiranaka Department of Orthopaedic Surgery, Okayama University Hospital Yuya Kodama Department of Orthopaedic Surgery, Okayama University Hospital Yusuke Kamatsuki Department of Orthopaedic Surgery, Okayama University Hospital Yuki Okazaki Department of Orthopaedic Surgery, Okayama University Hospital Tadashi Yamawaki Department of Orthopaedic Surgery, Okayama University Hospital Hirosuke Endo Department of Orthopaedic Surgery, Okayama University Hospital Toshifumi Ozaki Department of Orthopaedic Surgery, Okayama University Hospital Background The lengths of the anteromedial bundle (AMB) and posterolateral bundle (PLB) change during knee motion during double-bundle anterior cruciate ligament (ACL) reconstruction. However, the actual intra-articular graft length would be affected by the bone tunnel position and tunnel creation angle during ACL reconstruction. The aim of this study was to investigate the intra-articular length change of the AMB and PLB in patients who underwent anatomic double-bundle ACL reconstruction. Hypothesis We hypothesized that the PLB would show a more dynamic length change pattern than the AMB during knee flexion at ACL reconstruction. Methods Thirty-two patients (16 men and 16 women) who had isolated ACL injuries with intact menisci were investigated. Anatomic double-bundle ACL reconstructions were performed using semitendinosus tendon autografts at a mean age of 30.6 years. The graft and tunnel lengths were measured intraoperatively. Intra-articular graft lengths and length changes were calculated at 0° and 90° of knee flexion during ACL reconstruction. Intraoperative data were collected prospectively, and analyses were performed retrospectively. Results The intra-articular length of the AMB at 0° of knee flexion was 28.1±5.5mm. At 90° of knee flexion, the AMB intra-articular length decreased to 25.6±4.8mm. The intra-articular length of the PLB decreased to 17.7±4.6mm at 90° of knee flexion compared to 22.0±4.2mm at 0° of knee flexion. Changes in the intra-articular graft length during knee flexion were detected more in the PLB (4.1mm) than in the AMB (2.0mm, p=0.01). Discussion This study demonstrated that the intra-articular length change of the PLB during knee motion was larger than that of the AMB in anatomic double-bundle ACL reconstructions with semitendinosus tendon autografts and suspensory femoral fixation devices. Level of evidenceIV ; retrospective cohort study. No potential conflict of interest relevant to this article was reported.

岡山大学経済学会 Acta Medica Okayama 2433-4146 49 1 2017 教育による地方創生戦略 : 教育の町『和気』構想を一例に 41 68 EN Yasushi Iwabuchi Graduate School of Humanities and Social Sciences, Okayama University Miyuki Yoshikawa Takeshi Nagamune 10.18926/OER/55231 This article analyzes the importance of education when attempting regional revitalization by considering the case of the introduction of‘ an English Education District’ and a public cram school in a Japanese town. As Japan faces a depopulated society, it is important for local administrations to maintain their local population through public policy that supports economic activities and improves living conditions. Wake Town in Okayama Prefecture has already undertaken a variety of actions, supported by the human resources of the national government and private companies, to promote its livability. This article elucidates the reason behind Wake Town＇s strong commitment to its education policy, which has resulted in, for example, the creation of a public cram school. This article focuses on three points: （1） the background of the education policy in Wake Town, （2） the management of the newly established public cram school, and （3） the evaluation of this school in the view of its students and their parents. Finally, the article argues that free public education is becoming increasingly important for community development in the global era ofthe 21st century. No potential conflict of interest relevant to this article was reported.

岡山大学経済学会 Acta Medica Okayama 0386-3069 32 4 2001 産業進化と創業･成長支援策 65 100 EN Mitsllshige Nitta 10.18926/OER/41476 In the latter half in 1990's, the extensive public policies for promoting newly establishment of the enterprise (for example, "Law for facilitating the creation of New Business" enforced in 1999) were introduced in Japan. In this paper, I would like to search the theoretical background of such policy as the policy for promoting evolution of industry that the innovative activities were accompanied by newly establishment and discontinuance ofbusiness of the enterprise. To begin with, I carried out the fact finding on the relation between newly establishment and discontinuance of business using the data of "The 1999 Establishment and Enterprise Census." And I verified some hypotheses on the evolution of industries which Acs and Audretsch (1991) and Audretsch (1995) presented and tried the reexamination of these hypotheses. I set the increasing rate of newly establishment (the number of employee base) and the increasing rate of discontinuance of business (the number of employee base) during 1996-1999 period as main variables. I carried out the regression analysis on manufacturing industries and service industries (industrial classification of 2 and 3 digits), and confirmed that there was the positive correlation between the increasing rate of newly establishment and the increasing rate of discontinuance of business. I examined the ratio of increasing rate of discontinuance of business and increasing rate of newly establishment (D / E ratio) on enterprise scale (by the number of employee base) and industrial sector (industrial classification of 2 digits). As the result, I confirmed that the D / E ratio described the V-shaped curve with the extension of enterprise scale in many industrial sectors. I consider that the base point of this V-shaped curve shows minimum efficient scale. I confirmed that there was the positive correlation between this minimum efficient scale (D / E ratio at V-shaped base point) and employment increasing rate of the industrial sector. Based on these results of analysis, I describe some policy implications on the public policies for the newly establishment of enterprises and the initial support and growth support for the newly-established and smallscale enterprises. No potential conflict of interest relevant to this article was reported.