An experimental model of the production of early after depolarizations by injury current from an ischemic region

An ischemic myocardial region contains cells with a depolarized resting membrane potential. This depolarization leads to an intercellular current flow between the ischemic region and the surrounding normal myocardial cells which has been termed an injury current. We have devised an experimental model system in which an isolated guinea pig ventricular cell is electrically coupled to a model depolarized cell in order to evaluate the effects of this injury current on the electrical properties of a normal ventricular cell exposed to drugs which increase calcium current or decrease potassium current. Using low doses of isoproterenol, forskolin, or Bay K 8644 (or 8-bromo-cyclic adenosine monophosphate in the pipette) we found that the action potential duration of the isolated cell was lengthened, but that early after depolarizations (EADs) were not produced unless the cell was also coupled to a depolarized cell model representing an adjacent ischemic region. A similar prolongation of the action potential was produced by low doses of quinidine, but EADs were not produced unless coupling to a depolarized cell model was added. EADs could not be produced in any cells in the absence of the drugs even though the coupling to the depolarized cell model was increased up to the level at which the action potential was indefinitely prolonged. At higher isoproterenol concentrations, EADs or spontaneous activity were produced without coupling to the depolarized cell model. Under these conditions, coupling of the cell to a cell model with normal resting membrane potential stopped the spontaneous activity and prevented the occurrence of EADs even with high levels of resistive coupling. These findings suggest that the electrotonic influences of a localized depolarized region can produce EADs if the calcium current magnitude is increased, which would be the case for sympathetic innervation.     

Osteochondroma and secondary synovial osteochondromatosis

Secondary synovial osteochondromatosis (SOC) is a rare disorder caused by a variety of joint disorders. Two unusual cases of secondary SOC are presented. The first patient is a 43-year-old man with extensive SOC developing within a bursa surrounding an osteochondroma of the pubic bone. The second patient is a 23-year-old man who developed florid and progressive SOC of his hip joint following excision of a femoral neck osteochondroma. SOC recurred despite three excisions over a 15-month period. Imaging was useful in pre-operative diagnosis of bursal SOC in the first patient and in detecting multiple recurrences in the second patient. Both cases illustrate prominent SOC developing secondary to osteochondroma. The different hypotheses regarding bursal and secondary SOC are reviewed. Received: 8 October 1998 Revision requested: 28 October 1998 Revision received: 13 November 1998 Accepted: 16 November 1998     

Forces and moments on the human leg in the frontal plane during static bipedal stance.

An experimental apparatus was assembled that permitted measurement of the vertical and lateral ground reaction forces as the hip is abducted, resulting in foot separations ranging from 0.25 to 71 cm, with the knee in 0 degree flexion. Twelve healthy volunteers (8 men and 4 women) were tested. The hip joint was located by means of center of rotation measurements on each subject's legs, and the location of the knee joint was determined using anatomical measurements. It was observed that the mediolateral force was nonzero and directed toward the body midline, even when the subject's feet were placed together. With the feet placed at shoulder width, the population mean mediolateral force was 3% of body weight. It was determined that simplifying assumptions based upon either "zero lateral force," or "zero hip moment," produced errors, when compared with our measured values, over various ranges of foot separation, with the zero hip moment assumption providing accuracy over a broader range. The inclination of the tibial plateau, with respect to the long axis of the tibia, that would produce minimal mediolateral shear at the knee is presented. Research and clinical applications of our results and techniques are discussed.     

Treatment of 78 cases of shoulder periarthritis by warming-needle method

Jiansanzhen, Tianzong (SI 11), Jugu (LI 16), Jianzhen (SI 9), Binao (LI 14) and Quchi (LI 11) were given warming-needle moxibustion to treat shoulder periarthritis in 78 cases, and the result showed total effective rate was 97.4%. Author: LI Jian-wu (1955-), male, junior consultant doctor Translator: WU Xue-fei     

环枢关节紊乱症的临床研究

环枢关节紊乱症，从发病机理到临床表现，乃是颈椎病中较复杂的疑难顽症。用常规诊治方法，疗效不佳。本研究提出新的诊断依据与治疗方法，对３２０例病者随机分为治疗组１６６例（采用改进的诊治方法），对照组１５４例（用常规诊治方法）对照进行疗效观察。结果显示：治疗组治愈率与总有效率及康复率均高于对照组。有非常显著差异，Ｐ＜０．０１。而疗程较对照组短。环枢关节紊乱症的临床研究有利于颈椎病诊治水平的提高，运用于临床，疗效好，效益高，具有推广应用价值。     

双重法固定肩锁关节脱位

为介绍一种新方法修复肩锁关节脱位。肩锁关节脱位整复后采用双重法（交叉克氏针及8字钢丝）固定肩锁关节。结果：16例肩锁关节脱位后无一复发,关节功能无影响。结论：该法操作简单,固定牢靠,可早期行关节功能锻炼,可有效防止脱位复发。     

Assessment of patellar maltracking using combined static and dynamic MRI

Between January 1995 and Jul 1997, 474 patients with anterior knee pain resistant to conservative treatment were referred for MR of the knee. The MR examination consisted of routine sequences with an additional patellofemoral dynamic examination using a technique that has been developed at this institution. The dynamic study examines both knees simultaneously, with the patient supine and the quadriceps loaded. No gating or restraint apparatus is needed. Patellar subluxation or tilt was present in 188(40 %) of cases, bilateral in 104 and unilateral in 84 cases (right 39, left 45). It was classified as mild in 51 %, moderate in 39 % and severe in 10 %. Subluxation was more prevalent in females than males (42 % vs. 37 %) and this was most obvious in the severe group where 68 % were female. In 90 knees selected at random, four measurements of patellofemoral morphology were obtained using reconstructed images from a volume gradient echo sequence. These measurements were correlated with the degree of subluxation or tilt. A tibial tubercle distance greater than 20 mm, a femoral sulcus angle greater than 150 degrees, sulcus depth less than 4 mm were specific for subluxation but no measurement proved to be sufficiently sensitive to preclude a tracking study. MRI can be used to define more precisely the anatomy of the extensor mechanism and its relationship to the femur and tibia, in both a static and dynamic setting. In this way, patients with anterior knee pain can be classified more accurately and the outcomes of treatment more reliably assessed. Received: 17 September 1999; Revised: 31 January 2000; Accepted: 4 February 2000     

多种工作模式的踝关节活动器的研制

各种原因导致患者长期卧床后将引起严重的并发症:踝关节跖屈畸形。新型踝关节活动器以大扭矩、超低速电机为动力,结合定时控制电路,具有多种工作模式,能使踝关节在被动的情况下背伸20～30°,跖屈40～50°,并能根据患者的个体情况设置不同的运用角度与时间,且能根据需要进行缓慢、连续、往返式运动,这对那些踝关节不能或较难进行主动活动的病人防止踝关节跖屈畸形、踝关节僵硬的及下肢肌肉萎缩有良好的作用。     

血府逐瘀汤治疗髋关节置换术后非感染性发热

[目的]探讨髋关节置换术后非感染性发热的防治。[方法]应用血府逐瘀汤加减辨证论治。[结果]43例患者体温恢复正常,其中36例在3天内体温恢复正常。[结论]该方法对髋关节置换术后非感染性发热有较好作用。     

应用锁骨钩钢板治疗Tossy Ⅲ型肩锁关节脱位

目的探讨锁骨钩钢板治疗TossyⅢ型肩锁关节脱位的临床疗效。方法我们对2003年2月～2007年1月间52例TossyⅢ型肩锁关节脱位的患者均采用锁骨钩钢板复位内固定治疗。所有患者均未进行喙锁韧带缝合修复,但缝合损伤的肩锁关节囊及韧带和三角肌、斜方肌附丽。6～9个月后取出内固定。按Lazzcano法评定肩关节功能。结果52例患者得到随访,随访9～12个月,平均10个月。肩关节功能,取内固定前:优40例,良10例,差2例,优良率96%;取内固定后:优45例,良7例,差0例,优良率100%。肩关节功能取内固定前为良或差的病例在取出内固定后均有不同程度的改善。无切口感染、内固定松脱或断裂及再脱位等并发症。结论锁骨钩钢板是治疗TossyⅢ型肩锁关节脱位的最好治疗方法,具有操作简单,手术时间短,创伤小,可保证百分百复位,固定可靠,符合肩锁关节的生物力学要求,术后可早期功能锻炼,功能恢复好等特点。