1.A DYNAMIC MODEL OF BODY SWAY CONTROL DURING UPRIGHT STANCE IN HUMAN
YIFA JIANG ; SACHIO NAGASAKI ; HIDENORI KIMURA
Japanese Journal of Physical Fitness and Sports Medicine 2006;55(Supplement):S231-S236
The aim of this study is to establish a new dynamic model for balance keeping control in upright standing; and to deduce the underlying possible control mechanism of central neuronal system with a special concern on the roles of pelvis and its muscles. The dynamic model including five joints, i. e. two ankles, two hips and one lumbosacral making up a multi-link system being driven by two pairs of muscles, the psoas major (PM) and glutaeus medius (GM). In coronal section, experimental data shows the ankle and lumbosacral sway in almost the same amplitude, whereas their phase difference is approximately equal to π. The results indicate that the trunk is keeping perpendicularly to horizon during the standing process. By defining the model's physical parameters, assuming that the corrective torque needed for balance keeping process is regulated by PID (stands for proportional, integral and derivative) control, the body sway can be simulated. The simulation result is quite consistent with the experimental data suggests that the pelvis is one of the most important structure in balance keeping, moreover, the dynamics of the present proposed balance keeping model is a quite useful model for analyzing the posture sway.
2.THE RELATION BETWEEN TRUNK SWAY AND THE MOTION OF CENTRE OF PRESSURE DURING QUIET STANCE
YIFA JIANG ; SACHIO NAGASAKI ; TOSHIO MATSUOKA ; YOSHINORI FURUTA ; HIDENORI KIMURA
Japanese Journal of Physical Fitness and Sports Medicine 2003;52(5):533-541
The purpose of this study was to identify the relationships between trunk sway (TS) and the motion of center of pressure (COP) during quiet upright stance. Eight young healthy subjects (averaged 24±6.7 years) including 3 females were recruited for this study. By comparing TS with COP, we found that TS is moving in phase with COP both in lateral and sagittal plane. On the basis of observations that the COP-TS error signal is very similar to the changes of friction between the feet and floor. We also found that the friction is the impetus of trunk sway obeying the Newton's law. Then, a dynamic model between TS and COP can be identified. The results showed that TS and the motion of COP are in accordance with a specific differential equation. Supporting TS is v and COPS is u, then u can be expressed as : u=-Hm/k v+hv, where H, k, h are constants, m is the body mass. The simulation results fitted the experimental findings very well. The results suggested that TS instead of COP is a promising index for human standing ability assessment.
3.The Emergency Operation for Ruptured Dissecting Limited Abdominal Aortic Aneurysm.
Osamu Shigemitsu ; Tetsuo Hadama ; Yoshiaki Mori ; Tatsunori Kimura ; Shinji Mjyamoto ; Hidenori Sako ; Toru Soeda ; Yuzo Uchida
Japanese Journal of Cardiovascular Surgery 1995;24(6):368-372
The diagnosis of ruptured dissecting limited abdominal aortic aneurysm was made in four cases. The sex ratio (M/F) was 1/3, and mean age was 63.5 years (from 53 to 78yr). Only one of these cases die due to intraoperative bleeding. Other three cases were discharged from our hospital. Intraluminal proximal anastomosis after fixed dissected aortic wall due to mattress suture and end to end anastomosis with reinforcement by Teflon felt were good results. The one case who was anastomosed simple intraluminal method has pseudoaneurysm in the proximal portion. It is important to diagnose preoperatively dissection and to make end to end anastomosis with Teflon felt.
4.Successful Veno-Arterial Bypass Support Using Centrifugal Pump with Membranous Artificial Oxygenator in a Case of Cardiogenic Shock Following Coronary Artery Bypass Surgery for Acute Myocardial Infarction.
Tetsuo HADAMA ; Tatsunori KIMURA ; Hidemi TAKASAKI ; Yoshiaki MORI ; Osamu SHIGEMITSU ; Shinji MIYAMOTO ; Hidenori SAKO ; Takayuki NOGUCHI ; Yuzo UCHIDA ; Joji SHIRABE
Japanese Journal of Cardiovascular Surgery 1992;21(3):314-318
A 54-year-old man developed cardiogenic shock after acute myocardial infarction. Urgent coronary angiogram revealed complete occlusion at proximal portion of the right coronary artery and severe stenosis at just proximal site of the left anterior descending branch. Following thrombolytic therapy was not successful and he was sent to the operating room for coronary artery bypass surgery under external cardiac massage after 6hr from the onset. Three aorto-coronary bypasses were made to left anterior descending branch, first diagonal branch and right coronary artery using saphenous vein grafts by aortic cross-clamping of 67min. He fell into severe low cardiac output syndrome and could not be weaned from the cardiopulmonary bypass even by catecholamine infusions and IABP support. Veno-arterial bypass consisted of centrifugal pump and membranous artificial oxygenator was instituted. Venous blood was drained from the right atrium using percutaneous cannula via the right femoral vein and oxygenated blood was returned to the right subclavian artery. Hemodynamics recovered dramatically and after 71hr of this assisted circulation he was weaned from veno-arterial bypass. Activated coagulation time was maintained within 180-200sec. During this period, the centrifugal pump and oxygenator was not necessary to change and no clot was seen in the bypass system. He discharged from our hospital after 2 mo, postoperatively and now he is doing well as NYHA class-II 8 mo. postoperatively.
5.A Case Report of Recurrence of Angina Pectoris Caused by an Aortocoronary Venous Bypass Graft Aneurysm.
Tatsunori Kimura ; Tetsuo Hadama ; Hidemi Takasaki ; Yoshiaki Mori ; Osamu Shigemitsu ; Shinji Miyamoto ; Hidenori Sako ; Hirohumi Anai ; Tohru Soeda ; Yuzo Uchida
Japanese Journal of Cardiovascular Surgery 1994;23(1):59-62
We experienced a 51-year-old male case of CABG whose graftography one month after CABG revealed a 0.5cm venous bypass graft aneurysm. Anginal pain recurred in the eighth month after CABG. Re-graftography showed enlargement of the aneurysm and stenosis of the graft at the same site. Re-CABG was carried out successfully and his postoperative course was good. Venous graft aneurysm is a comparatively rare complication, and that of the present case was considered to be most ascribable to the fragility of the graft, caused by mediastinitis secondary to the first CABG. Thrombus formation was noted in the aneurysm, with a risk of causing rupture or myocardial infarction. Therefore, such graft aneurysms should be treated by re-CABG as soon as possible after detection.
6.A Case of Multiple Aortic Aneurysms in Marfan's Syndrome Recognized following Rupture of an Abdominal Aortic Aneurysm.
Hidenori Sako ; Tetsuo Hadama ; Yoshiaki Mori ; Osamu Shigemitsu ; Tatsunori Kimura ; Katsushige Ono ; Shinji Miyamoto ; Hirofumi Anai ; Tohru Soeda ; Yuzo Uchida
Japanese Journal of Cardiovascular Surgery 1994;23(2):118-121
A 27-year-old female with Marfan's syndrome underwent successful emergency surgery for rupture of an abdominal aortic aneurysm. Annulo-aortic ectasia with a saccular aneurysm of the aortic arch was revealed by angiography after the initial operation. Cabrol's operation with replacement of the aortic arch was performed. Because bleeding from the distal anastomotic portion was uncontrollable, the segment was ligated and an extra-anatomical bypass was performed from the ascending aortic graft to the bilateral femoral arteries. Intra-graft balloon pumping was carried out in the extra-anatomical bypass graft while the patient was in low cardiac output condition after the second operation. This was considered to be an effective circulatory assist procedure.
7.A Case of Successful Management of an Abdominal Aortic Aneurysm extending to the Sigmoid Colon with Hemorrhagic Shock.
Takashi Miyamoto ; Testsuo Hadama ; Yoshiaki Mori ; Osamu Shigemitu ; Tatsunori Kimura ; Shinji Miyamoto ; Hidenori Sako ; Tooru Soeda ; Okihiko Shibata ; Yuuzou Uchida
Japanese Journal of Cardiovascular Surgery 1995;24(6):401-403
A 58-year-old man was admitted with pulsatile abdominal mass with fever and dull pain. Abdominal aortic aneurysm with left hydronephrosis due to obstruction of the left ureter was diagnosed by CT scanning. Aortic valve replacement was performed ten years previously for aortic regurgitation and recently his cardiac function deteriorated. On the 5th day after admission he suddenly suffered from hemorrhagic shock with massive melena. Emergency laparotomy was performed and ruptured abdominal aortic aneurysm was observed penetrating to the sigmoid colon with perianeurysmal abscess. The abdominal aorta was excluded and closed using two-layer sutures just below the renal artery, and bilateral common iliac arteries were also closed. The aneurysmal sac and the sigmoid colon were removed as a whole, and colostomy was made according to Hartmann's procedure. Permanent right axillo-bifemoral bypass graftiny was made to avoid infectious complications of the vascular graft. A successful vascular reconstruction was done without any complication of graft infection, however he died of cardiac failure due to dilated cardiomyopathy after 4 months postoperatively. We reported a successfully treated abdominal aortic aneurysm extending to the sigmoid colon with hemorrhagic schok.
8.Benign biliary stricture caused by transduodenal lumen-apposing metal stent placement for pancreatic acute necrotic collection
Shuhei SHINTANI ; Takuya OKAMOTO ; Kosuke HIROE ; Hidenori KIMURA ; Hiroto INOUE ; Atsushi NISHIDA ; Osamu INATOMI
International Journal of Gastrointestinal Intervention 2025;14(1):24-27
A 58-year-old male patient presented with acute alcohol-induced severe necrotizing pancreatitis. He reported a symptomatic acute necrotic collection in the pancreatic head. No improvements were observed despite one week of antimicrobial therapy. Endoscopic ultrasound-guided drainage via the superior duodenal angle was conducted and a lumen-apposing metal stent (LAMS) was placed. He had an obstructive jaundice progression 3 days postintervention. Endoscopic retrograde cholangiography showed that the cystic side flange of the LAMS caused the distal bile duct smooth stricture. The jaundice improved immediately after the placement of plastic stent in the bile duct, and the LAMS could be removed on the 15th day after placement. The plastic stent was removed after 4 months, and the biliary stricture improved, with no recurrence of jaundice. Here, we report a case of successful conservative treatment of a benign biliary stricture caused by the distal flange of the LAMS.
9.Benign biliary stricture caused by transduodenal lumen-apposing metal stent placement for pancreatic acute necrotic collection
Shuhei SHINTANI ; Takuya OKAMOTO ; Kosuke HIROE ; Hidenori KIMURA ; Hiroto INOUE ; Atsushi NISHIDA ; Osamu INATOMI
International Journal of Gastrointestinal Intervention 2025;14(1):24-27
A 58-year-old male patient presented with acute alcohol-induced severe necrotizing pancreatitis. He reported a symptomatic acute necrotic collection in the pancreatic head. No improvements were observed despite one week of antimicrobial therapy. Endoscopic ultrasound-guided drainage via the superior duodenal angle was conducted and a lumen-apposing metal stent (LAMS) was placed. He had an obstructive jaundice progression 3 days postintervention. Endoscopic retrograde cholangiography showed that the cystic side flange of the LAMS caused the distal bile duct smooth stricture. The jaundice improved immediately after the placement of plastic stent in the bile duct, and the LAMS could be removed on the 15th day after placement. The plastic stent was removed after 4 months, and the biliary stricture improved, with no recurrence of jaundice. Here, we report a case of successful conservative treatment of a benign biliary stricture caused by the distal flange of the LAMS.
10.Benign biliary stricture caused by transduodenal lumen-apposing metal stent placement for pancreatic acute necrotic collection
Shuhei SHINTANI ; Takuya OKAMOTO ; Kosuke HIROE ; Hidenori KIMURA ; Hiroto INOUE ; Atsushi NISHIDA ; Osamu INATOMI
International Journal of Gastrointestinal Intervention 2025;14(1):24-27
A 58-year-old male patient presented with acute alcohol-induced severe necrotizing pancreatitis. He reported a symptomatic acute necrotic collection in the pancreatic head. No improvements were observed despite one week of antimicrobial therapy. Endoscopic ultrasound-guided drainage via the superior duodenal angle was conducted and a lumen-apposing metal stent (LAMS) was placed. He had an obstructive jaundice progression 3 days postintervention. Endoscopic retrograde cholangiography showed that the cystic side flange of the LAMS caused the distal bile duct smooth stricture. The jaundice improved immediately after the placement of plastic stent in the bile duct, and the LAMS could be removed on the 15th day after placement. The plastic stent was removed after 4 months, and the biliary stricture improved, with no recurrence of jaundice. Here, we report a case of successful conservative treatment of a benign biliary stricture caused by the distal flange of the LAMS.