Blood supply of the quadriceps tendon

Degenerative changes have been considered to be a cause for spontaneous quadriceps tendon rupture. Aim of this study is to investigate the microvasculature of the quadriceps tendon by injection techniques and immunohistochemical methods (antibodies against laminin) with regard to the pathogenesis of tendon degeneration. The blood supply of the quadriceps tendon arises from descending branches of the lateral circumflex femoral artery, by branches of the descending geniculate artery and by branches of the medial and lateral superior geniculate arteries. Blood vessels penetrate the tendon from the surrounding connective tissue and anastomose with a longitudinally orientated intraligamentous network. Compared to the surrounding synovial layer, the amount of vessels in the tendon substance is greatly reduced. The distribution of blood vessels within the quadriceps tendon is not homogenous. The anterior or superficial part of the tendon has a complete vascular network that extends from the musculo-tendinous junction to the patella. Within the deep portion of the quadriceps tendon there is an oval shaped avascular area which measures app. 30 mm in length and app. 15 mm in width. Within this area the immunohistochemical proof of laminin is negative. An explanation for the absence of blood vessels may be compressive stress caused by the patellar groove which serves as hypomochlion for the quadriceps tendon when the knee is flexed. The occurrence of an avascular zone within the deep layer of the tendon that is directed to the joint cavity may explain the frequency of degenerative changes in this region.     

Blood supply of the quadriceps tendon

Degenerative changes have been considered to be a cause for spontaneous quadriceps tendon rupture. Aim of this study is to investigate the microvasculature of the quadriceps tendon by injection techniques and immunohistochemical methods (antibodies against laminin) with regard to the pathogenesis of tendon degeneration. The blood supply of the quadriceps tendon arises from descending branches of the lateral circumflex femoral artery, by branches of the descending geniculate artery and by branches of the medial and lateral superior geniculate arteries. Blood vessels penetrate the tendon from the surrounding connective tissue and anastomose with a longitudinally orientated intraligamentous network. Compared to the surrounding synovial layer, the amount of vessels in the tendon substance is greatly reduced. The distribution of blood vessels within the quadriceps tendon is not homogenous. The anterior or superficial part of the tendon has a complete vascular network that extends from the musculo-tendinous junction to the patella. Within the deep portion of the quadriceps tendon there is an oval shaped avascular area which measures app. 30 mm in length and app. 15 mm in width. Within this area the immunohistochemical proof of laminin is negative. An explanation for the absence of blood vessels may be compressive stress caused by the patellar groove which serves as hypomochlion for the quadriceps tendon when the knee is flexed. The occurrence of an avascular zone within the deep layer of the tendon that is directed to the joint cavity may explain the frequency of degenerative changes in this region.     

Blood and lymph supply of the anterior cruciate ligament: Cadaver study by immunohistochemical and histochemical methods

Injection techniques, immunohistochemical (antibodies against laminin), and histochemical (5-nucleotidase activity) methods were used to demonstrate the vascular pattern of the human anterior cruciate ligament (ACL). The major blood supply of the ACL arises from the middle geniculate artery. The distal part of the ACL is vascularized by branches of the inferior geniculate artery. The ligament is covered by a synovial fold where the terminal branches of the middle and the inferior geniculate artery form a periligamentous network. From the synovial sheath, the blood vessels penetrate the ligament in a horizontal direction and anastomose with a longitudinally orientated intraligamentous network. Within the ligament, the blood vessels are located in the loose connective tissue that is located between longitudinal fiber bundles. Compared to the surrounding synovial layer, the number of vessels in the ligament substance is greatly reduced. Three avascular areas can be detected within the ligament. In the attachment zones of the ligament to the femur and the tibia, the immunohistochemical reaction with antibodies against laminin is negative. A third avascular zone is located in the anterior portion approximately 0.5 cm proximal to the tibial insertion. The absence of blood vessels in this area may be the result of compressive stress caused by the anterior end of the notch. Lymphatics accompany most of the smaller blood vessels, showing similar regional distribution.     

Vascular supply of the femoral head in sheep—Implications for the ovine femoroacetabular impingement model

Sheep hips have a natural non‐spherical head similar to a cam‐type deformity in human beings. By performing an intertrochanteric varus osteotomy, cam‐type femoroacetabular impingement can be induced experimentally. In sheep, the aspherical portion is located superiorly—exactly matching the region where the superior retinacular vessels enter the femoral head–neck junction in human beings. In order to fully exploit the potential of this experimental FAI model, a safe osteochondroplasty of the superior asphericity would need to be done without the risk of avascular necrosis. The aim of this study was to describe the vascular anatomy of the femoral head in sheep from the aorta to the retinacular vessels in order to perform safe femoral osteochondroplasty of the superior femoral asphericity in sheep. Sixty‐two ovine hips were analyzed using CT angiography (30 hips), post mortem intravascular latex injection (6 hips), vascular corrosion casting (6 hips), and analysis of the distribution of vascular foramina around the femoral head–neck junction in macerated ovine femora (20 hips). The ovine femoral head receives its blood supply from anterior retinacular arteries from the lateral femoral circumflex artery, and from posterior retinacular arteries from the medial femoral circumflex artery. The superior aspherical portion is free of vessels. Detailed knowledge about vascular anatomy of sheep hips is of clinical significance since it allows to perform osteochondroplasty of the superior aspherical portion in the experimental ovine FAI model safely without the risk of osteonecrosis. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:2340–2348, 2018.

     

Cross-bridge free skin flap transfer: case report

The authors present a procedure that can be used in cases of massive skin and soft tissue defect accompanied by extensive vascular injury. The technique involves the use of two donor components (a free skin flap and a vascular donor) which form a single unit postoperatively. The free flap is stretched over crossed limbs, with its major lateral portion serving to cover the defect, and the margin of its medial portion containing the flap pedicle sutured to a pedicled skin flap from the healthy contralateral limb. End-to-end anastomoses of vessels from both components are performed within the skin bridge that connects the crossed limbs. A temporary cross-over vascular supply to the free flap from vessels of the healthy limb is thus created. The procedure is offered as a satisfactory solution to the problem of transferring free flaps in cases where recipient site vessels are absent or unusable.     

香猪的皮肤血管来源和构筑特点

目的 为了给整形外科提供理想的研究皮瓣成活机理的动物模型。方法 利用皮肤透明标本制作技术,对香猪皮肤血管的来源和构筑进行探讨。结果 ①香猪体型小,皮肤脂肪丰富;②皮肤血管来源可分为三类：肌皮穿支、肌间隔（隙）穿支和直接皮肤动脉;③香猪的皮肤血管可分为四层：浅盘膜学层血管网、浅筋膜中层血管网、浅筋中层血管网和真皮下血管网;④躯干和颈部的血管密度高,血管网丰富而层次清楚,而四肢的血管密度低,血管网稀而     

Spontaneous rupture of hepatocellular carcinoma and vascular injury

HYPOTHESIS: Because spontaneous rupture of hepatocellular carcinoma (HCC) is one kind of bleeding complication related to the blood vessels, the possible mechanism of this rupture should occur on the blood vessel itself. Our hypothesis, which has not yet been investigated, is that the vascular integrity of HCC might be damaged during vascular injury. DESIGN: We examined semiquantitatively the expression of von Willebrand factor, elastin, neutrophil elastase, type IV collagen, and collagenase in 23 specimens of HCC with spontaneous rupture by immunohistochemistry, and compared them with 30 specimens of HCC without rupture. RESULTS: There was a significant decrease of von Willebrand factor, proliferation of degenerated elastin, abnormal distribution of neutrophil elastase, degradation of type IV collagen, and increase in collagenase production around the blood vessels in ruptured HCC. Since the decreased expression of von Willebrand factor is an indicator of vascular injury and elastase and collagenase are present in inflammatory processes, we postulate that the vascular injury probably exists before spontaneous rupture of HCC occurs. The blood vessel dysfunction resulting from the degeneration of elastin and the degradation of type IV collagen can render the blood vessels stiff and weak, causing them to split easily when the vascular load increases from hypertension or minor mechanical trauma. CONCLUSION: Spontaneous rupture of HCC may be related to the vascular dysfunction.     

Clinical application of phase contrast angiography]

"Phase Contrast Angiography" is a new technique of Magnetic Resonance Angiography as reported by Dumoulin CL et al. Using this technique, we can obtain images of vessels (angiograms) without injection of contrast medium. We present the results of phase contrast angiography on cerebral and spinal vascular disease. We utilized the General Electric SIGNA, 1.5 tesla NMR. One hundred and ninety-one cases of cerebral and spinal vascular diseases were scanned using phase contrast angiography. Included were 90 cases of occlusive vascular disease, 16 cases of moyamoya disease, 39 cases of arteriovenous malformation, and 28 aneurysms. The phase contrast angiography uses flow encoding gradient pulses, which impart a velocity-dependent phase shift to the transverse magnetization of moving spins. The resulting image contains only information from the moving spins; while information from stationary tissue remains suppressed. In cases using 3-D angiogram, we made 32 images 6 degrees apart in their projection direction and displayed them on a video terminal. We were able to visualize occlusions of vessels, aneurysms, bypassed vessels, and abnormal vessels of arteriovenous malformations. Retrospective evaluation comparing phase contrast angiography with conventional angiography of the stenotic findings on the horizontal portion of middle cerebral arteries (64 vessels of 32 patients), resulted in a false positive ratio of 39.1%. We obtained clinically valuable results regarding the hydrodynamics of patients using "phase contrast angiography" non-invasively. These results reveal not only "anatomical" images of vessels, but also "functional" images, which are sensitive to the pattern of the blood flow. This study would strongly suggest that phase contrast angiography presents a valuable tool for the clinical diagnosis of cerebral and spinal vascular diseases.     

Blood supply of the tibialis anterior tendon

Injection techniques and immunohistochemical methods (antibodies against laminin) were performed to uncover the vascular pattern of the human tibialis anterior tendon with regard to spontaneous rupture of this tendon. Proximally, the blood supply of the tibialis anterior tendon mainly arises from the anterior tibial artery. Distally, the tendon is supplied by branches of the medial tarsal artery. Blood vessels enter the peritenon via vinculae from the posterior side. From the peritenon, the blood vessels penetrate the tendon and anastomose with a longitudinally orientated intratendinous network. Compared with the surrounding peritenon, the number of vessels in the tendon substance is greatly reduced. The distribution of blood vessels within the anterior tibial tendon is not homogenous. The posterior part of the tendon has a complete vascular network that extends from the musculotendinous junction to the insertion at the bone. In the anterior half of the tendon, there is an avascular zone between 45 and 67 mm in length. The location of the avascular zone correlates well with the location of the most frequent site of spontaneous rupture of the tibialis anterior tendon reported in the literature. Hypovascularity has to be considered as an etiological cofactor for spontaneous rupture of the tibialis anterior tendon.     

Anatomy of the anterior cruciate ligament

The anterior cruciate ligament (ACL) is a multifascicular structure whose femoral and tibial attachments, as well as spatial orientation within the knee, are directly related to its function as a constraint of joint motion. The ACL is made up of multiple collagen bundles that give rise to the multifascicular nature of the ligament. This arrangement results in a different portion of the ligament being taut and therefore functional, throughout the range of motion. The ACL receives its blood supply from branches of the middle genicular artery, which from a vascular synovial envelope around the ligament. These periligamentous vessels penetrate the ligament transversely and anastomose with a longitudinal network of endoligamentous vessels. The body attachments do not contribute significantly to the vascularity of the ligament. The nerve supply to the ACL originates from the tibial nerve. Although the majority of fibers appear to have a vasomotor function, some fibers may serve a proprioceptive or sensory function.     

阴股沟皮瓣应用解剖学研究

目的明确阴股沟皮瓣的解剖学基础.方法对10具(20侧)成年女尸阴股沟区皮肤进行解剖学研究.结果阴股沟皮瓣存在多重血液供应;其中,闭孔动脉前皮支分布于皮瓣中部,浅出点距会阴正中线(3.0±0.5)cm,距阴道口前缘(1.7±0.4)cm距耻骨下支外侧缘(0.6±0.2)cm,管径(0.8±0.1)mm;阴唇后动脉主要供应大阴唇,并恒定地以本干的形式在大阴唇皮下与阴部外浅动脉形成血管吻合,在阴道口后缘前后各1.5cm的范围内,发出2、3支阴唇后动脉外侧支,外径为(0.7±0.3)mm,分布于阴股沟皮瓣后部;阴部外浅动脉斜形穿过皮瓣上端走向大阴唇,沿途发出柳枝状血管分支分布于皮瓣上端.结论阴股沟皮瓣阴道再造所利用的血管是阴唇后动脉外侧支,而非阴唇后动脉主干;由于闭孔动脉前皮支浅出点位置较高而且固定,以之为蒂形成的皮瓣不适用于阴道再造,而适合于会阴部较小皮肤缺损的修复.     

Blood supply of the peroneal tendons: Injection and immunohistochemical studies of cadaver tendons

We studied the vascular pattern of human peroneal tendons with injection techniques and immunohistochemically by using antibodies against laminin. The main blood supply arises from the peroneal artery. The distal part of the peroneus longus tendon is supplied by branches of the medial tarsal artery. Blood vessels enter the peritenon of both tendons via a mesotenon from the posterior aspect. From the peritenon, the blood vessels penetrate the peroneus brevis and peroneus longus tendons and anastomose with a longitudinally-oriented intratendinous network. The amount of vessels in the tendon substance is consistently less than in the surrounding peritenon. The distribution of blood vessels in the peroneal tendons is not homogeneous. In the region where the peroneus brevis tendon passes through the fibular groove, the longitudinally-oriented intratendinous vascular network is interrupted and the tendon is almost avascular. In this region, the tendon is squeezed between the peroneus longus tendon and the bony slide bearing of the lateral malleolus. The peroneus longus tendon has two avascular zones. In the region where the peroneus longus tendon curves around the lateral malleolus and the peroneal trochlea of the calcaneus, the anterior part of the tendon which is directed towards the pulley is avascular. A second avascular zone is located more distally in the region where the tendon changes direction and wraps around the cuboid.     

Blood supply of the peroneal tendons: injection and immunohistochemical studies of cadaver tendons

We studied the vascular pattern of human peroneal tendons with injection techniques and immunohistochemically by using antibodies against laminin The main blood supply arises from the peroneal artery. The distal part of the peroneus longus tendon is supplied by branches of the medial tarsal artery. Blood vessels enter the peritenon of both tendons via a mesotenon from the posterior aspect. From the peritenon, the blood vessels penetrate the peroneus brevis and peroneus longus tendons and anastomose with a longitudinally-oriented intratendinous network. The amount of vessels in the tendon substance is consistently less than in the surrounding peritenon. The distribution of blood vessels in the peroneal tendons is not homogeneous. In the region where the peroneus brevis tendon passes through the fibular groove, the longitudinally-oriented intratendinous vascular network is interrupted and the tendon is almost avascular. In this region, the tendon is squeezed between the peroneus longus tendon and the bony slide bearing of the lateral malleolus. The peroneus longus tendon has two avascular zones. In the region where the peroneus longus tendon curves around the lateral malleolus and the peroneal trochlea of the calcaneus, the anterior part of the tendon which is directed towards the pulley is avascular. A second avascular zone is located more distally in the region where the tendon changes direction and wraps around the cuboid.     

Blood supply of the peroneal tendons: Injection and immunohistochemical studies of cadaver tendons

We studied the vascular pattern of human peroneal tendons with injection techniques and immunohistochemically by using antibodies against laminin. The main blood supply arises from the peroneal artery. The distal part of the peroneus longus tendon is supplied by branches of the medial tarsal artery. Blood vessels enter the peritenon of both tendons via a mesotenon from the posterior aspect. From the peritenon, the blood vessels penetrate the peroneus brevis and peroneus longus tendons and anastomose with a longitudinally-oriented intratendinous network. The amount of vessels in the tendon substance is consistently less than in the surrounding peritenon. The distribution of blood vessels in the peroneal tendons is not homogeneous. In the region where the peroneus brevis tendon passes through the fibular groove, the longitudinally-oriented intratendinous vascular network is interrupted and the tendon is almost avascular. In this region, the tendon is squeezed between the peroneus longus tendon and the bony slide bearing of the lateral malleolus. The peroneus longus tendon has two avascular zones. In the region where the peroneus longus tendon curves around the lateral malleolus and the peroneal trochlea of the calcaneus, the anterior part of the tendon which is directed towards the pulley is avascular. A second avascular zone is located more distally in the region where the tendon changes direction and wraps around the cuboid.     

The vascular wall as a regulator of tissue oxygenation

PURPOSE OF REVIEW: The development of the phosphorescence quenching oxygen measurement technique has allowed for a simultaneous measurement of intra and perivascular partial pressure oxygen along arteriolar vessels in vivo. Mapping the microvascular distribution and oxygen gradients across the vascular walls using this high-resolution technique reveals the existence of large radial gradients between the vasculature and the tissue, with concomitant longitudinal oxygen loss. Mass balance analysis along vessel segments indicates that the vascular wall has a high rate of oxygen consumption. This review presents the current status of in-vivo studies on the partitioning of oxygen between blood, the vascular wall and the surrounding tissue, thereby positioning an oxygen sink between blood and tissue regulating oxygen release. RECENT FINDINGS: Induced vasoactivity (vasoconstriction and vasodilation) has been shown to modulate oxygen consumption of the vascular wall and directly affect the portion of oxygen available to the tissue. Inhibition of the endothelial layer of the vessel wall resulted in a decrease in the oxygen gradient across the vessel. SUMMARY: The vascular wall is a sink for oxygen. The modulation of vessel wall oxygen consumption can substantially impact the amount of oxygen released to the tissue.     

Characteristics of special circulations

Blood flow through a vascular bed is usually determined by the pressure gradient across it and the diameter of the precapillary resistance vessels. Special circulations have additional specific features of blood flow control. Several organs control their blood supply by autoregulation. Coronary blood flow is linked to myocardial oxygen consumption, primarily by a metabolic mechanism. Increases in demand or decreases in supply of oxygen cause the release of vasodilator metabolites, which act on vascular smooth muscle to cause vessel relaxation and hence increase blood flow. Cerebral blood flow is primarily regulated by a myogenic mechanism whereby increases in transmural pressure stretch the vascular smooth muscle, which responds by contracting. Renal blood flow is regulated by both extrinsic and intrinsic mechanisms; sympathetic vasoconstriction of the afferent arterioles reduces renal blood flow in response to a decrease in effective circulating volume, myogenic mechanisms and tubuloglomerular feedback, as well as the release of vasoactive metabolites from the vascular endothelium regulate renal blood flow intrinsically. Hepatic blood flow is delivered via the portal vein and hepatic artery, and the amount of flow varies in these vessels reciprocally to maintain constant total blood flow. The pulmonary circulation receives the entire cardiac output, and blood flow is regulated both passively and actively. Pulmonary vessels are highly distensible and can accommodate increases in blood flow without significant increases in pressure.     

Characteristics of special circulations

Blood flow through a vascular bed is usually determined by the pressure gradient across it and the diameter of the precapillary resistance vessels. Special circulations have additional specific features of blood flow control. Several organs control their blood supply by autoregulation. Coronary blood flow is linked to myocardial oxygen consumption, primarily by a metabolic mechanism. Increases in demand or decreases in supply of oxygen cause the release of vasodilator metabolites, which act on vascular smooth muscle to cause vessel relaxation and hence increase blood flow. Cerebral blood flow is primarily regulated by a myogenic mechanism whereby increases in transmural pressure stretch the vascular smooth muscle, which responds by contracting. Renal blood flow is regulated by both extrinsic and intrinsic mechanisms; sympathetic vasoconstriction of the afferent arterioles reduces renal blood flow in response to a decrease in effective circulating volume, myogenic mechanisms and tubuloglomerular feedback, as well as the release of vasoactive metabolites from the vascular endothelium regulate renal blood flow intrinsically. Hepatic blood flow is delivered via the portal vein and hepatic artery, and the amount of flow varies in these vessels reciprocally to maintain constant total blood flow. The pulmonary circulation receives the entire cardiac output, and blood flow is regulated both passively and actively. Pulmonary vessels are highly distensible and can accommodate increases in blood flow without significant increases in pressure.     

Characteristics of special circulations

Blood flow through a vascular bed is usually determined by the pressure gradient across it and the diameter of the precapillary resistance vessels. Special circulations have additional specific features of blood flow control. Several organs control their blood supply by autoregulation. Coronary blood flow is linked to myocardial oxygen consumption, primarily by a metabolic mechanism. Increases in demand or decreases in supply of oxygen cause the release of vasodilator metabolites, which act on vascular smooth muscle to cause vessel relaxation and hence increase blood flow. Cerebral blood flow is primarily regulated by a myogenic mechanism whereby increases in transmural pressure stretch the vascular smooth muscle, which responds by contracting. Renal blood flow is regulated by both extrinsic and intrinsic mechanisms; sympathetic vasoconstriction of the afferent arterioles reduces renal blood flow in response to a decrease in effective circulating volume, myogenic mechanisms and tubuloglomerular feedback, as well as the release of vasoactive metabolites from the vascular endothelium regulate renal blood flow intrinsically. Hepatic blood flow is delivered via the portal vein and hepatic artery, and the amount of flow varies in these vessels reciprocally to maintain constant total blood flow. The pulmonary circulation receives the entire cardiac output, and blood flow is regulated both passively and actively. Pulmonary vessels are highly distensible and can accommodate increases in blood flow without significant increases in pressure.     

Air pressure vascular clamp. Experimental study and clinical application]

An air pressure vascular clamp was designed for vascular surgery. On femoral arteries of 90 rats, vascular injury and anastomosis experiments were made to compare this clamp with 2 other vascular clamps commonly used, and the pressure on blood vessels from different clamps was determined. Examination with operating, light and electron microscopes showed that the number of vascular injuries and their degree were the least after use of this clamp, the pressure of which could be adjusted just to block blood flow, suitable for blood vessels of different calibers. Satisfactory results have been obtained through its clinical application in 43 patients having 119 vascular anastomoses. It is thought that the unobstructed rate of vascular anastomosis can be raised by the application of this vascular clamp, especially for vessels of small caliber and long period of compression.     

血管硬化性病变与肝癌自发性破裂的关系

目的 探讨血管壁弹性变化与肝癌自发性破裂的相关关系。方法 选用肝癌破裂及未破裂患者的肝癌组织标本各30例，采用免疫组化ABC法及电子显微镜检测其与血管病变有关的因素：第八因子相关抗原因子(vWF因子)、弹性硬蛋白、弹性蛋白酶(中性粒细胞性)。结果与未破裂组相比，肝癌破裂患者中血管内皮vWF因子表达量明显下降，小动脉壁中弹性蛋白酶分布异常、弹性硬蛋白增生过度、弹力膜断裂。vWF因子为血管受损指标之一，并参与凝血过程。上述病变的结果，导致患者小动脉壁脆性增加及凝血功能下降，稍遇外力的作用即易发生血管破裂，进而可导致肿瘤组织的破裂。结论肝癌患者体内的血管壁硬变可能与肝癌肿瘤破裂有关。