Adductor Canal Block or Local Infiltrate Analgesia for Pain Control After Total Knee Arthroplasty? A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background

Total knee arthroplasty is a treatment option for debilitating arthritis. In the postoperative period, patients experience moderate to severe pain affecting the rehabilitation, hospital stay, and patient satisfaction. This study aims at utilizing current best evidence to determine whether adductor canal block (ACB) or periarticular injection (PAI) is a better modality for managing short-term postoperative pain and opioid consumption.

国人上矢状窦窦腔内结构的内镜解剖

目的观察国人上矢状窦窦腔内结构，特别是纤维索和蛛网膜颗粒的完整解剖形态。方法成人头颅标本5具，去除颅盖，应用内镜观察研究上矢状窦窦腔内纤维索及蛛网膜颗粒的原始结构特征；并纵行剖开管腔，显微镜下观察纤维索、蛛网膜颗粒。结果内镜下观察上矢状窦管腔内纤维索大致分3种类型：瓣膜状（47．1％）、小梁状（30．6％）、板层状（22．3％）。蛛网膜颗粒多集中于上矢状窦中段侧壁及静脉隐窝处呈指状突起突入窦腔。结论内镜较常规解剖手段可以更直观地观察上矢状窦窦腔内结构的完整形态特征。     

Cast syndrome

The term cast syndrome is used to denote duodenal obstruction occurring after application of a corrective plaster cast to patients with scoliosis. We report a classical case in a 14-year-old female who required surgical intervention after conservative treatment failed. Six months later the patient had no further gastrointestinal symptoms. Clinical, radiological, and pathological details as well as the surgical treatment are described and discussed. Offprint requests to: M. E. Martín Hortigüela     

Cobalt-dependent potentiation of net inward current density in Helix aspersa neurons.

A low concentration of transition metal ions Co2+ and Ni2+ increases the inward current density in neurons from the land snail Helix aspersa. The currents were measured using a single electrode voltage-clamp/internal perfusion method under conditions in which the external Na+ was replaced by Tris+, the predominant external current carrying cation was Ca2+, and the internal perfusate contained 120 mM Cs+/0 K+; 30 mM tetraethylammonium (TEA) was added externally to block K+ current. In the presence of Co2+ (3 mM) or Ni2+ (0.5 mM) inward Ca2+ currents were stimulated normally by voltage-dependent activation of Ca2+ channels. There was a 5-10% decrease in the rate of rise of the inward current. The principal effect of Co2+ and Ni2+ in increasing the current density seems to be a decrease in the rate at which the inward currents decline during a depolarizing voltage pulse. The results may be due to a decrease in a voltage-dependent or Ca(2+)-dependent outward current and/or an inhibition of Ca2+ channel inactivation. Outward current under these conditions (zero internal K+) was significant and most likely due to Cs+ efflux through the voltage-activated or Ca(2+)-activated nonspecific cation channels. Co2+ is an extremely effective blocker of this outward current. These results are not an artifact of internal perfusion or the special ionic conditions. Intracellular recording of unperfused neurons in normal Helix Ringer's solution showed that the Ca(2+)-dependent action potential duration was increased significantly by low concentrations of Co2+. This result is consistant with the Co(2+)-dependent increase in inward (depolarizing) current seen in voltage-clamp experiments.     

Local fibrinolysis for superior mesenteric artery thromboembolism

A 66-year-old man with atrial fibrillation was referred soon after developing left lower limb and abdominal pain with rectal bleeding. An immediate flush aortogram showed embolic occlusion of the left distal superficial femoral artery and superior mesenteric artery (SMA), 3 cm from its ostium. Recombinant tissue plasminogen activitor (rtPA) 40 mg was selectively in stilled in the SMA in two boluses. Abdominal symptoms resolved within 48 h, and complete recanalization of the SMA was shown on angiography. Exploratory laparotomy after 72 h showed a normal small bowel and right colon, and was completed by femoropopliteal embolectomy. Six months later, the patient remained asymptomatic.     

Recurrent cerebral venous infarcts and superior vena cava obstruction: case report

Abstract We report a patient with repeated venous infarcts in the occipital lobe and occlusion of the superior vena cava. The pathogenetic relationships between the superior vena cava occlusion and the brain infarcts are discussed. High pressure in the superior venous territory and incomplete patency of the transverse sinus are probably responsible for the venous infarcts. Received: 12 July 1996 Accepted: 27 August 1996     

Morphometric analysis of the great vessels in early fetal life

Pathological examination of the heart and great vessels wasperformed in 61 specimens obtained after surgical terminationof pregnancy for psychosocial indications at 9–18 weeksof gestation. The aorta and pulmonary trunk were identifiedand external diameters were measured at the level of, and distalto the aortic valve and pulmonary valve, the level of the aorticisthmus and thoracic aorta, and the proximal and distal ductusarteriosus. All eight vessel diameters increased linearly withgestational age and the ratio of the diameter of the aorticisthmus to that of the aortic valve or the distal ductus arteriosusalso increased with gestation. Early pregnancy is characterizedby rapid growth of the fetal head and this may well be the consequenceof a preferential distribution of left ventricular output infavour of the head due to relative narrowing of the aortic isthmusat this gestation.     

Spatial relation of the acetylcholinesterase-rich domain to the visual topography in the feline superior colliculus

Summary The superior colliculus (SC) of the cat shows a prominent compartmentalized organization at the level of its intermediate layers. The mosaic of these compartments is apparent in the pattern of acetylcholinesterase (AChE) staining. Patches of high AChE-activity are sharply set off from surrounding areas in the caudal SC while they are less distinct anteriorly. The rostral part lacks such obvious compartments. Thus, a structural reorganization apparently cuts across the topographical representations spread out in the SC. In order to test if this compartmental gradient relates to the topographic maps of the colliculus, retinotopic landmarks were visualized in the superficial layers by labeling the retinotectal pathway. In the SC ipsilateral to the eye injected with horseradish peroxidase (HRP) a paucity of labeling indicated the zone representing the ipsilateral visual half-field. Serial reconstructions of collicular sections, cut longitudinally or tangentially, revealed that the non-compartmentalized part of the intermediate layers corresponds to the representation of the ipsilateral visual half-field in the layers above, while an intricate mosaic array of compartments prevail in tectal zones related to the representation of the contralateral visual half-field.     

Visual orientation in the rat: A dissociation of deficits following cortical and collicular lesions

Summary Rats with either bilateral ablations of superior colliculus, bilateral ablations of visual cortex, or sham operations were trained to run across a large arena towards a small illuminated target which varied in location from trial to trial. An impairment in this visually-guided running was apparent in the cortical group, but not in the collicular group. When, in a second experiment, the spatial relationships within the apparatus were changed by extending the entry-tunnel some distance into the arena, the running of the cortical group became even more impaired, while the collicular animals continued to run towards the targets under efficient visual control. In a third experiment, the effect of introducing a novel flashing light in various locations around the perimeter of the arena was investigated. It was found that unlike the other two groups, the collicular animals showed no orienting reflex to the novel stimulus when it was presented outside a broad central area of the visual field.The authors acknowledge the financial support of the Science Research Council (grant no B/RG/61112)     

Receptive fields of single cells in the cat's superior colliculus

Summary Receptive field analysis of single units in the superior colliculus of the mid-pontine, pretrigeminal cat has confirmed previous reports of directionally selective units in the tectum. The directional property was based principally upon a unilateral inhibitory mechanism, although some directional responses to small moving objects depended equally upon summation of excitation. Receptive field size varied greatly, with field diameters not uncommonly exceeding 30 degrees. Fields near the area centralis and along the horizontal meridian tended to be smaller than those elsewhere. An inhibitory influence from the field periphery was demonstrated.Post-doctoral fellow of the National Science Foundation. Present address: Department of Experimental Psychology, Walter Reed Army Institute of Research, Washington, D. C. 20012 (USA).