前交叉韧带股骨等距重建位置的比较

目的 :比较模拟生理负荷条件下前交叉韧带股骨重建位置的等距特性。方法 :7具新鲜冷冻尸体膝关节标本 ,在前交叉韧带胫骨附着区取 3点以及胫骨附着区取 5点分别钻骨隧道 ,通过钢丝和等距测量器施加初负荷 ,检测膝关节屈曲过程中胫骨和股骨隧道间的距离变化。结果 :膝关节从 0～ 90°屈曲过程中 ,股骨韧带附着区中点、上点和后点与胫骨附着区 5点间呈等距变化 ,但股骨韧带附着区中点、上点与胫骨附着区 5点间距离变化具有组内显著性差异。结论 :股骨韧带附着区后点是理想的等距重建点。     

负荷条件下前交叉韧带的股骨重建位置

目的　探讨模拟生理负荷条件下前交叉韧带股骨等距重建位置。方法　 7具新鲜冷冻膝关节标本 ,在前交叉韧带股骨附着区取 5点以及胫骨附着区中点分别钻骨隧道 ,通过钢丝和等距测量器施加初负荷 ,检测膝关节屈曲过程中胫骨和股骨隧道间的距离变化。结果　膝关节 0°～ 90°屈曲过程中 ,股骨韧带附着区中点、后点和下点与胫骨附着区中点间呈等距变化 ,而股骨韧带附着区前点和上点与胫骨附着区中点间距离变化超过生理等距界限。结论　股骨韧带附着区后点和下点是理想的前交叉韧带股骨等距重建点。股骨韧带附着区中点、后点和下点的连线构成了前交叉韧带的股骨等距重建区。     

前交叉韧带重建术中胫骨侧止点无撞击区的定位研究

目的探讨前交叉韧带(ACL)重建术中胫骨隧道无撞击重建区的定位。方法选用10具正常新鲜冷冻尸体膝关节标本,膝关节完全伸直时,标记髁间窝顶延长线和ACL胫骨附着处的交点。膝关节屈曲90°时,测量ACL胫骨附着处上标记点与ACL前缘间的距离及标记点与胫骨棘间区后缘间的距离。然后,再测量标记点前部分的前后径、后部分的前后径和内外径,并计算后部分的面积。结果由ACL胫骨附着处前缘到胫骨棘间区后缘的前后径平均为(21.40±1.17)mm。ACL胫骨附着处标记点前部分的前后径平均为(8.90±0.74)mm(占总前后径的41.59%)。胫骨附着处标记点后部分的前后径平均为(12.50±0.85)mm(占总前后径的58.41%),内外径平均为(10.65±0.97)mm,面积平均为(133.80±21.01)mm2。结论ACL胫骨附着处上标记点的后部分是胫骨隧道无撞击区,位于胫骨棘间区的后缘中点与该点前12.50mm之间,在该区域行ACL重建可以避免移植物与髁间窝顶部的撞击。绝对撞击区位于ACL胫骨附着部前缘与其后8.90mm之间,应尽量避免在此区域内定位胫骨隧道。     

膝关节前交叉韧带前内束和后外束股骨止点位置的解剖研究

目的探讨膝关节前交叉韧带（ACL）前内束及后外束股骨止点的解剖位置,找到确定ACL前内束和后外束股骨止点的简单可行的方法,为双束重建ACL手术中的股骨骨道定位提供理论支持。方法解剖18个新鲜膝关节标本（25～45岁）的股骨端前内束和后外束的足迹,以标定前内束和后外束股骨止点中心点的位置。在屈膝90°位,测量ACL前内束及后外束股骨止点中心点距股骨髁间窝外侧壁前方、后方和下方软骨缘的距离。再对测量数据进行评估和对比。结果 ACL后外束股骨止点中心点距离股骨前方软骨缘（8.55±1.33）mm,距离股骨后方软骨缘（8.65±1.54）mm,二者间无统计学差异（t=-0.191,P〉0.05）;而ACL后外束股骨止点中心点距离股骨下方软骨缘（5.11±0.79）mm。ACL前内束股骨止点中心点距离股骨前方软骨缘（14.95±2.06）mm,距离股骨后方软骨缘（6.08±0.88）mm,二者间有统计学差异（t=16.633,P〈0.01）;而ACL前内束股骨止点中心点距离股骨下方软骨缘（9.10±1.55）mm。结论膝关节屈膝90°时,ACL后外束的股骨止点中心点位于股骨髁间窝外侧壁距离下方软骨缘5mm的高度,并处在与前方和后方软骨缘几乎等距的位置。而ACL前内束的股骨止点中心点位于股骨髁间窝外侧壁距离下方软骨缘9mm的高度,并处在前后连线大约后1/3的位置。在ACL双束重建的手术中,应用本研究的结果能够简单、快捷地确定ACL前内束和后外束股骨骨道位置。     

前交叉韧带重建术中胫骨骨道定位的应用解剖研究

[目的]探究前交叉韧带(anterior cruciate ligament,ACL)于胫骨止点处的解剖形态以及测量髁间窝顶线与胫骨平台交汇点至后交叉韧带前缘的距离对胫骨骨道定位的解剖学意义,为ACL重建术提供理论依据。[方法]选取新鲜成人膝关节标本8例,仔细剔除关节周围肌肉、后关节囊等结构,保留前后交叉韧带及两侧侧副韧带,保证膝关节正常屈伸范围。在屈伸膝关节时按照ACL纤维张力区将其分为前内束和后外束,在胫骨附着处将ACL切断制备ACL损伤模型。用测量工具和Phontoshop软件获取ACL基本解剖参数以及髁间窝顶线与胫骨平台的交汇点、ACL前缘、ACL胫骨止点的中心点分别至后交叉韧带前缘的距离。[结果]ACL平均体部直径为(11.21±0.76)mm,ACL在胫骨止点处的平均最大横径为(11.34±0.79)mm,平均最大前后径为(16.54±0.82)mm。前内束和后外束在胫骨止点处的平均面积分别为(113.35±29.65)mm~2和(83.29±16.99)mm~2。髁间窝顶线与胫骨平台的交汇点、ACL前缘以及ACL胫骨止点的中心点至后交叉韧带前缘的距离分别为(12.13±0.96)mm,(21.14±0.83)mm和(8.82±0.77)mm。[结论]利用胫骨平台骨道定位ACL在股骨的解剖止点现实可行,在ACL重建术中具有重要意义。     

前交叉韧带重建术股骨侧定位点及移植物直径变化与膝关节旋转稳定性相关性研究

目的根据前交叉韧带重建术后胫骨结节与股骨滑车沟的距离(TT-TG值)的变化,探讨股骨侧隧道定位点和移植物直径对膝关节旋转稳定性的影响。方法回顾性分析自2016-03—2016-10诊治42例前交叉韧带损伤,均行韧带重建术,根据术后CT三维重建结果,行2种试验,A试验:股骨侧隧道(移植物)直径一致,比较不同隧道定位点与膝关节TT-TG值的相关性。B试验:股骨侧定位点一致,比较不同的隧道直径与膝关节TT-TG值的相关性。结果 A试验中,移植物直径恒定,随着定位点越接近后外侧束,TT-TG值越大。B试验中,定位点保持一致,隧道直径越不同,TT-TG值差异无统计学意义。结论前交叉韧带重建后,股骨侧定位点越靠近后外侧束附丽区,矫正因前交叉韧带损伤导致的膝关节内旋畸形的能力越强即TT-TG值越大,因此后外侧束对维持膝关节旋转稳定性十分重要。移植物直径对膝关节旋转稳定性影响不显著。     

前内侧入路解剖重建单束前交叉韧带的临床评估

目的评估关节镜下经前内侧入路解剖重建单束前交叉韧带(ACL)的位置、形态及临床效果。方法对25例ACL断裂患者在关节镜下经前内侧入路应用解剖重建技术行单束ACL重建术,移植物应用自体腘绳肌腱。术后行X线、MRI检查,了解骨道情况,观察移植物形态及张力,并与11例健侧膝关节的正常ACL进行对比。应用Lysholm评分系统评估膝关节功能。结果术后X线片显示股骨隧道内口位于髁间窝顶与股骨后缘皮质线交叉点前缘,胫骨隧道内口位于髁间窝顶后方。MRI显示所有重建ACL张力良好,ACL上倾角为50.82°±4.57°,胫骨平台止点至前缘距离与平台纵径比值为0.50±0.04,两项与对照组比较差异均无统计学意义(P0.05)。患者均获得随访,时间为13~44个月。Lysholm评分术后为92.20分±4.29分,明显高于术前的64.76分±7.16分(P0.01)。结论关节镜下经前内侧入路解剖重建ACL的位置及形态接近解剖结构,早中期临床效果满意。     

胫骨隧道位置对前交叉韧带重建术后膝关节稳定性的影响

<正>关节镜前交叉韧带(anterior cruciate ligament,ACL)重建是骨科常见手术之一,生理性等长重建使移植物在膝关节屈伸过程中所受的张力相近。隧道制备中关于股骨隧道定位等距性及生物力学的研究较多,但有关胫骨隧道定位对生物力学影响的报道较少。     

前交叉韧带重建中移植物固定方法的研究进展

目前,前交叉韧带(ACL)重建手术的成功率为80%～90%,有10%～30%的患者术后有持续性膝关节疼痛和不稳[1].因ACL重建术后的康复方案强调即刻的完全活动度、恢复神经肌肉功能及早期完全负重,所以,术后早期是移植物固定的薄弱环节.现已知不同固定部位的生理特性不同,胫骨固定部位的骨密度较股骨低,移植物的受力方向与胫骨隧道共线,而仅在膝关节弯曲100°时与股骨隧道共线,不同位置(胫骨或股骨)和组织类型(软组织或骨栓)的固定方法不同.本文就ACL重建中使用的移植物固定方法及其相关研究进展作一综述.     

同种异体骨-髌腱-骨重建前交叉韧带术后骨隧道扩大的分析

目的 探讨同种异体骨-髌腱-骨(B-PT-B)重建前交叉韧带(ACL)术后股骨和胫骨的骨隧道的改变及其对临床疗效的影响.方法 2004年1月～2005年12月对30例ACL断裂患者在关节镜监视下应用同种异体B-PT-B单束重建ACL.术后膝关节功能锻炼采用保守的康复训练方案.分别于术后1周和12个月应用磁共振测量股骨和胫骨骨隧道关节面内口的直径.术后12个月以Lysholm评分观测膝关节功能,应用KT-1000测量膝关节屈30°时的胫骨相对活动度. 结果本组30例ACL重建患者术后33%(10/30)的患者出现股骨和(或)胫骨骨隧道扩大,其中69%(11/16)的骨隧道扩大范围在2～6 mm;骨隧道扩大各级别之间的Lysholn疗效评分、术后KT值差异无统计学意义(P＞0.05).结论 同种异体B-PT-B移植重建ACL术后骨隧道可有不同程度的扩大;骨隧道扩大小于6 mm时,对膝关节的功能恢复无明显影响.     

Vasopressor hormone response following mesenteric traction during major abdominal surgery

Background : We investigated the vasopressor hormone response following mesenteric traction (MT) with hypotension due to prostacyclin (PGI₂) release in patients undergoing abdominal surgery with a combined general and epidural anesthesia. Methods : In a prospective, randomized, placebo-controlled study we administered 400 mg ibuprofen (i.v.) in 42 patients scheduled for abdominal surgery. General anesthesia was combined with epidural anesthesia (T4-L1). Before as well as 5, 15, 30, 45, and 90 min after MT we recorded plasma osmolality, hemodynamics and measured 6-keto-PGFlα (stabile metabolite of PGI₂), TXB₂ (stabile metabolite of thromboxane A₂) active renin, and arginine vasopressin (AVP) plasma concentrations by radioimmunoassay. Catecholamine levels were assessed by high-pressure liquid chromatography (HPLC) with electrochemical detection. Results : Following MT, arterial hypotension occurred along with a substantial PGI₂ release. This was completely abolished by ibuprofen administration. Although plasma levels of 6-keto-PGF_1α (1133 (708) vs. 60 (3) ng/L, median (median absolute deviation), P=0.0001, placebo vs. ibuprofen) remained significantly elevated, blood pressure was restored within 30 min after MT in the placebo group. At the same point in time plasma concentrations of TXB² (164 (87) vs. 58 (1) ng/L, P=0.0001), epinephrine (46 (33) vs. 14 (6) ng/L, P=0.001), AVP (41 ± (18) vs. 12 (7) ng/L, P=0.0004), and active renin (27 (12) vs. 12 (4) ng/L, P = 0.001) were significantly higher in placebo-treated patients. Conclusion : Under combined general and epidural anesthesia arterial hypotension following MT due to endogenous PGI₂ release is associated with enhanced release of AVP, active renin, epinephrine and thromboxane A₂, presumably contributing to hemodynamic stability within 30 min after MT.     

A Teaspoon Pump for Pumping Blood with High Hydraulic Efficiency and Low Hemolysis Potential

Abstract: Virtually all blood pumps contain some kind of rubbing, sliding, closely moving machinery surfaces that are exposed to the blood being pumped. These valves, internal bearings, magnetic bearing position sensors, and shaft seals cause most of the problems with blood pumps. The original teaspoon pump design prevented the rubbing, sliding machinery surfaces from contacting the blood. However, the hydraulic efficiency was low because the blood was able to "slip around" the rotating impeller so that the blood itself never rotated fast enough to develop adequate pressure. An improved teaspoon blood pump has been designed and tested and has shown acceptable hydraulic performance and low hemolysis potential. The new pump uses a nonrotating "swinging" hose as the pump impeller. The fluid enters the pump through the center of the swinging hose; therefore, there can be no fluid slip between the revolving blood and the revolving impeller. The new pump uses an impeller that is comparable to a flexible garden hose. If the free end of the hose were swung around in a circle like half of a jump rope, the fluid inside the hose would rotate and develop pressure even though the hose impeller itself did not "rotate"; therefore, no rotating shaft seal or internal bearings are required.     

A comparison of the inhibitory effects of four volatile anaesthetics on the metabolism of chlorzoxazone, a substrate for CYP2E1, in rabbits

Background: Halothane inhibits in vitro and in vivo activity of cytochrome P-450 (CYP) 2E1. There are several fluorinated volatile anaesthetics besides halothane, and most of them are defluorinated by CYP2E1. It is unclear whether other fluorinated anaesthetics inhibit the in vivo activity of CYP2E1.
Methods: We compared the inhibitory effects of therapeutic concentrations of four inhalational anaesthetics, halothane, enflurane, isoflurane, and sevoflurane, on chlorzoxazone metabolism in rabbits receiving artificial ventilation.
Results: All four inhalational anaesthetics decreased arterial blood pressure and increased plasma chlorzoxazone concentration. However, no significant differences in the plasma chlorzoxazone concentration were found between the four anaesthetics. The estimated chlorzoxazone clearance increased after beginning inhalation with all four agents, but no significant difference in clearance was noted between agents.
Conclusions: At therapeutic concentrations, the in vivo inhibitory effect on chlorzoxazone metabolism was similar for all four inhalational anaesthetics examined, even though their chemical characteristics and extent of hepatic metabolism differ considerably.     

Microspheres Based Detoxification System: A New Method in Convective Blood Purification

Abstract: A variety of protein-bound or hydrophobic substances, accumulating as a result of pathologic conditions such as exogenous or endogenous intoxications, are removed poorly by conventional detoxification methods because of low accessibility (hemodialysis), insufficient adsorption capabilities (hemosorption), low efficiency (peritoneal dialysis), or economic limitations (high-volume plasmapheresis). Combining advantages of existing methods with microspheric technology, a module-based system was designed. Major operating parameters of the latter can be modified to allow for adjustment to individual clinical situations. An extracorporeal blood circuit including a plasmafilter is combined with a secondary high-velocity plasma circuit driven by a centrifugal pump. Different microspheric adsorbers can be combined in one circuit or applied in sequence. Thus, a prolonged treatment can be tailored using specially designed selective adsorber materials. Comparing this system with existing methods (high-flux hemodialysis, molecular adsorbent recycling system), results from our in vitro studies and animal experiments demonstrate the superior efficiency of substance removal.     

Tissue perfusion in relation to cardiac output during continuous positive-pressure ventilation and administration of propranolol or verapamil

Background : Our objective was to determine whether administration of propranolol or verapamil modifies the hemodynamic adaptation to continuous positive-pressure ventilation (CPPV), in particular the regional distribution of cardiac output (CO).
Methods : General hemodynamics and regional blood flows assessed by microsphere technique (15 (μm) were recorded in 16 anesthetized pigs during spontaneous breathing (SB) and CPPV with 8 cm H₂O end-expiratory pressure (CPPV8) before and after intravenous administration of propranolol (0.3 mg · kg⁻¹ followed by 0.15 mg · kg⁻¹ · h⁻¹, n=8) or verapamil (0.1 mg · kg⁻¹ followed by 0.3 mg · kg⁻¹ · h⁻¹, n=8).
Results : CPPV8 depressed CO by 25% without shifts in its relative distribution with the exception of a noteworthy increase in adrenal perfusion. Propranolol increased arterial blood pressure, and due to a fall in heart rate, CO dropped by 25%. The kidneys and, to a lesser extent, the splanchic region and central nervous system received increased fractions of the remaining CO at the expense of skeletal muscle flow. Similar patterns were seen during SB and CPPV8 such that the combination of propranolol and CPPV8 depressed CO by 50%. The circulatory effects of verapamil were less evident but myocardial perfusion tended to increase.
Conclusions : The combination of propranolol or verapamil with CPPV does not result in any specific hemodynamic interaction in anesthetized pigs, except that the combined effect of propranolol and CPPV may severely reduce CO.     

Bariatric Surgery in Some "Central and East-European (former Eastern bloc)"Countries - Current Status and Prediction for the Next Millennium

Background: Obesity is increasing globallly, including in the formerly "Eastern Bloc" countries. Methods: A survey was made of obesity and bariatric surgery. Results: In the 8 East and Central European countries studied, with total population 300 million, roughly 43% of the population was overweight (BMI 25-30), 23% obese (BMI > 30), with about 15 million people morbidly obese (BMI > 40). From 0-10 morbidly obese individuals/100,000/year undergo bariatric surgery. Conclusion: Most countries were found to provide inadequate treatment for obesity.The majority of the morbidly obese are not treated effectively. However, health-care awareness of obesity and bariatric surgeons are slowly increasing.     

Volatile anaesthetics reduce adhesion of blood platelets under low-flow conditions in the coronary system of isolated guinea pig hearts

Background : Inhibitory effects of volatile anaesthetics on platelet aggregation have been demonstrated in several studies. However, the influence of volatile anaesthetics on intracoronary platelet adhesion has not been elucidated so far.
Methods : Isolated hearts of guinea pigs were perfused with buffer in the absence or presence of volatile anaesthetics (0.5 and 1 MAC) at constant coronary flow rates of 5 ml/min for 25 min, then 1 ml/min for 30 min and again 5 ml/min for 10 min. Before, during and after low-flow perfusion, a bolus of human platelets was applied into the coronary system. To simulate thrombogenic conditions, 0.3 U/ml human thrombin was infused during low-flow perfusion and reperfusion. The number of platelets sequestered to the endothelium was calculated from the difference between coronary in- and output of platelets. The myocardial production of lactate and consumption of pyruvate and coronary perfusion pressure were also determined.
Results : At a flow rate of 5 ml/min only about 3% of the applied platelets did not emerge from the coronary system, in any group. In contrast, 13.1±1.2% (mean±SEM) of infused platelets became adherent in low-flow perfusion in the control group without anaesthetic. The adherence was reduced with each 1 MAC isoflurane (to 6.2±1.2%), sevoflurane (to 4.4±0.9%) or halothane (to 3.2±1.5%) (each P <0.05 vs. control). Volatile anaesthetic, 0.5 MAC, did not inhibit platelet adhesion to a statistically significant extent in any case. Perfusion pressure and metabolic parameters were not statistically different between the control and the hearts exposed to anaesthetics.
Conclusion : Volatile anaesthetics in a concentration of 1 MAC can reduce the adhesion of platelets in the coronary system under reduced flow conditions. This action does not arise from vasodilation or inhibition of ischaemic stress.     

Synergistic interaction between the effects of propofol and midazolam with fentanyl on phrenic nerve activity in rabbits

Background: It has been shown that the depressive effects of both propofol and midazolam on consciousness are synergistic with opioids, but the nature of their interactions on other physiological systems, e. g. respiration, has not been fully investigated. The present study examined the effect of propofol and midazolam alone and in combination with fentanyl on phrenic nerve activity (PNA) and whether such interactions are additive or synergistic. Methods: PNA was recorded in 27 anaesthetised and artificially ventilated rabbits. In three groups, propofol, fentanyl and midazolam were administered intravenously in incremental doses to construct dose-response curves for the depressant effects of each one on PNA. In another two groups, the effect of pretreatment with either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. on the effects of propofol and fentanyl respectively on PNA were studied. Results: Propofol and fentanyl caused a dose-dependent depression of PNA with complete abolition at the highest total doses of 16 mg · kg^?1 i. v. and 32 μg · kg^?1 i. v., respectively. In contrast, midazolam in incremental doses to a total of 0.8 mg · kg^?1 reduced mean PNA by 63%, but approximately 12% of PNA remained at a total dose as high as 6.4 mg · kg^?1. The mean ED₅₀s, calculated from dose-response curves, were 5.4 mg · kg^?1, 3.9 μg · kg^?1 and 0.4 mg · kg^?1 for propofol, fentanyl and midazolam, respectively. Initial doses of either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. acted synergistically with subsequent doses of either propofol or fentanyl to abolish PNA at total doses of 8 mg · kg^?1 and 8 μg · kg^?1, respectively. Conclusion: Fentanyl has a synergistic interaction with both propofol and midazolam on PNA and hence potentially on respiration.     

Influence of dopexamine hydrochloride on haemodynamics and regulators of circulation in patients undergoing major abdominal surgery

Background: Catecholaminergic support is often used to improve haemodynamics in patients undergoing major abdominal surgery. Dopexamine is a synthetic vasoactive catecholamine with beneficial microcirculatory properties. Methods: The influence of perioperative administration of dopexamine on cardiorespiratory data and important regulators of macro- and microcirculation were studied in 30 patients undergoing Whipple pancreaticduodenectomy. The patients received randomized and blinded either 2 μg · kg^?1 · min^?1 of dopexamine (n=15) or placebo (n=15, control group). The infusion was started after induction of anaesthesia and continued until the morning of the first postoperative day. Endothelin-1 (ET-1), vasopressin, atrial natriuretic peptide (ANP), and catecholamine plasma levels were measured from arterial blood samples. Measurements were carried out after induction of anaesthesia, 2 h after onset of surgery, at the end of surgery, 2 h after surgery, and on the morning of the first postoperative day. Results: Cardiac index (CI) increased significantly in the dopexamine group (from 2.61±0.41 to 4.57±0.78 1 · min^?1 · m^?2) and remained elevated until the morning of the first postoperative day. Oxygen delivery index (DO₂I) and oxygen consumption index (VO₂I) were also significantly increased in the dopexamine group (DO₂I: from 416±91 to 717±110 ml/m² · m²; VO₂I: from 98±25 to 157±22 ml/m² · m²), being significantly higher than in the control group. pHi remained stable only in the dopexamine patients, indicating adequate splanchnic perfusion. Vasopressive regulators of circulation increased significantly only in the untreated control patients (vasopressin: from 4.37±1.1 to 35.9±12.1 pg/ml; ET-1: from 2.88±0.91 to 6.91±1.20 pg/ml). Conclusion: Patients undergoing major abdominal surgery may profit from prophylactic perioperative administration of dopexamine hydrochloride in the form of improved haemodynamics and oxygenation as well as beneficial influence on important regulators of organ blood flow.     

Systemic analgesia adapted to the children's condition

A concept of balanced analgesia using nonsteroidal anti-inflammatory drugs (NSAIDs), paracetamol (acetaminophen), opioids, and corticosteroids can also be used in patients with pre-existing illnesses. NSAIDs are the most effective treatment for acute pain of moderate intensity in children; however, these drugs should be avoided in patients at increased risk for serious side effects, e.g. patients with renal impairment, bleeding tendency, or extreme prematurity. NSAIDs can be given with minimal risks to the younger child with mild to moderate asthma, and, in these patients, the use of steroids can be encouraged; in addition to their antiemetic and analgesic action, a beneficial effect on asthma symptoms can be expected. In the non-intubated child with cerebral trauma, exaggerated sedation caused by opioids and increased bleeding tendency caused by NSAIDs must be avoided. In neonates and small infants, the oral administration of sucrose or glucose is helpful to minimize pain reaction during short uncomfortable interventions.