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71.
Anterior lumbar fusion using a hybrid interbody graft   总被引:3,自引:0,他引:3  
Summary This is a radiographic report of 40 patients (20 men, 20 women) who underwent anterior lumbar interbody fusions (73 levels) utilizing a “hybrid” interbody graft composed of femoral cortical allograft (FCA) bone and iliac crest cancellous autograft bone. The average age at surgery was 38 years (range 17–64 years), and follow-up averaged 1.4 years (range 1.0–2.4 years). Nineteen of the patients had undergone previous lumbar surgery. Thirty-two patients (63 levels) underwent anterior fusion combined with some type of posterior fixation, and eight patients (10 levels) had no posterior fixation. Types of posterior fixation included: for 20 patients (36 levels) Steffee variable screw placement fixation, for 10 patients (23 levels) translaminar facet screws (TFS), for 1 patient (3 levels) Knodt rods and for 1 patient (1 level) facet screws. Based on the persistence of lucent lines at the graft-host interface, three patients (one level each) were felt to have non-unions at their latest follow-ups at 1.4, 1.5 and 2.0 years, respectively. Two of these patients had no posterior fixation, and the other had TFS fixation. The overall fusion rate was 96% (70 of 73 levels). The fusion rate for all levels treated with posterior fixation was 98% compared with 75% for those without fixation. Intervertebral disc heights (IVDH) were measured on all films and corrected for magnification with computer assistance. On average, the IVDH was increased postoperatively but returned to preoperative values at follow-up. IVDH loss was independent of the type of instrumentation used. No complications arose from the use of the hybrid graft. Incorporation of the allograft portion of the graft is slow and was felt to be complete in only 7 of the 73 levels at follow-up. We conclude that the hybrid interbody graft technique is a safe and reliable method for performing anterior lumbar interbody fusions and should be combined with some type of posterior fixation. Long-term follow-up will be required to assess the behaviour of the allograft until incorporation is complete.  相似文献   
72.
Summary The delayed onset of symptomatic pain following lumbar discography (with no immediate pain response) is described in six patients, five with a minimum 2-year follow-up. It is usually seen in patients with nearly normal disc morphology who have incomplete or discrete annular tears that are not filled at the time of injection. Later (2–12 h in this study), dye leakage occurs through these lesions, thereby precipitating the discogenic pain This phenomenon may be missed and is probably more common than previously believed due to early discharge from the hospital, the patient expecting discomfort after the invasive study (hence no complaint is made), and the clinician being unaware of this delayed symptom, thereby not asking about it in follow-up. Close patient questioning regarding a delayed onset of symptomatic pain after discography is, therefore, an essential element in diagnostic information following this study.  相似文献   
73.
A novel approach that uses the concepts of parallel imaging to grid data sampled along a non-Cartesian trajectory using GRAPPA operator gridding (GROG) is described. GROG shifts any acquired data point to its nearest Cartesian location, thereby converting non-Cartesian to Cartesian data. Unlike other parallel imaging methods, GROG synthesizes the net weight for a shift in any direction from a single basis set of weights along the logical k-space directions. Given the vastly reduced size of the basis set, GROG calibration and reconstruction requires fewer operations and less calibration data than other parallel imaging methods for gridding. Instead of calculating and applying a density compensation function (DCF), GROG requires only local averaging, as the reconstructed points fall upon the Cartesian grid. Simulations are performed to demonstrate that the root mean square error (RMSE) values of images gridded with GROG are similar to those for images gridded using the gold-standard convolution gridding. Finally, GROG is compared to the convolution gridding technique using data sampled along radial, spiral, rosette, and BLADE (a.k.a. periodically rotated overlapping parallel lines with enhanced reconstruction [PROPELLER]) trajectories.  相似文献   
74.
Two cases are reported in which, after ACL reconstruction with autologous hamstring grafts, tibial polylactide interference screws migrated into the knee joint. Clinically, both patients presented with recurrent locking of the joint. In one case, a broken 15 mm-long tip of the screw was found intra-articularly. In the other case, the whole screw had migrated into the joint cavity. The degradation process of polylactic acid, operative technique and bone quality are discussed as possible reasons for these complications.  相似文献   
75.
多层面CT重建诊断中央大气道良性病变   总被引:7,自引:0,他引:7  
目的 :分析多层面CT三维重建诊断中央大气道良性病变的价值。材料和方法 :用多层面CT对 3 5例中央气道良性病变 (解剖性异常 5例 ,炎症性病变 18例及其它 12例 )扫描 ,并全部完成三维表面遮盖显示、容积显示和仿真内窥镜检查。所有病例第一次读片时仅有横断面图像 ,第二次读片时增加重建图像。结果 :三维重建帮助 4例横断面漏误诊的解剖性异常获得确诊 ,16例炎症性病变进一步详细显示 ,2例气管支气管裂伤明确范围和程度 ;虚拟内窥镜帮助 5例横断面上不能确诊的痰液获得确诊。结论 :CT三维重建可用于解剖性异常和痰液的诊断 ,对其它良性疾病主要是对病变的另一种形式的进一步显示。  相似文献   
76.
关节镜下股骨单隧道与双隧道重建后十字韧带的疗效分析   总被引:18,自引:0,他引:18  
目的分析比较关节镜下单束单隧道与双束股骨双隧道重建后十字韧带(PCL)术后的临床效果。方法1999年1月~2001年12月,采用单束前外束重建法重建PCL 18例,男14例,女4例;年龄18~50岁,平均35.5岁;右膝12例,左膝6例。移植物为骨-髌腱(中1/3)-骨的11例,半腱肌腱和股薄肌腱的7例。于PCL股骨附着点解剖中心的稍前方钻取股骨隧道,屈膝70°,拉紧并固定移植物。2000年1月~2002年12月,采用双束股骨双隧道法重建PCL12例,男10例,女2例;年龄21~47岁,平均33岁;右膝9例,左膝3例。移植物为半腱肌腱和股薄肌腱的7例,一端带髌骨块的股四头肌肌腱的5例。将肌腱编织分为两束。于股骨侧钻取双隧道。两束分别于屈膝70°和0°时拉紧并固定。结果采用前外束重建法的18例患者平均随访23个月,采用双束股骨双隧道重建法的12例患者平均随访17个月。前外束重建组与双束股骨双隧道重建组随访时的Lysholm评分分别为(92.4±3.7)分和(94.3±3.4)分,两组间差异无显著性(P>0.05)。屈膝0°和30°时,前外束重建组的胫骨后移距离是(5.9±0.4)mm和(6.2±0.5)mm,双束股骨双隧道重建组是(3.5±0.3)mm和(4.0±0.4)mm,两组间差异有显著性(P<0.05);屈膝60°和90°时,两组胫骨后移距离差异无显著性(P>0.05)。结论双束股骨双隧道重建PCL的方法优于前外  相似文献   
77.
目的比较关节镜下采用四股和八股腘绳肌肌腱双束重建前十字韧带的临床效果。方法2001年9月至2002年8月,将76例陈旧性前十字韧带损伤患者随机分为两组进行双束重建。一组采用四股腘绳肌肌腱移植物:取同侧半腱肌肌腱,做成两个两股肌腱移植物,分别重建前十字韧带前、后束;一组采用八股腘绳肌肌腱移植物:取同侧半腱肌肌腱做成一个四股肌腱移植物重建前束,取同侧股薄肌肌腱做成另一个四股肌腱移植物重建后束。按照IKDC、Lysholm和Tegner膝关节评分标准评价疗效。结果四股肌腱移植物组有33例、八股肌腱移植物组有35例获得随访,随访时间1~3年,平均16个月。四股肌腱移植物组KT-1000检查示,双侧膝关节前向松弛度差异<3mm者25例(75.8%,25/33),3~5mm者5例(15.2%,5/33),6~10mm者3例(9.1%,3/33);轴移试验阴性28例(84.8%),阳性5例(15.2%)。八股肌腱移植物组KT-1000检查示,双侧膝关节前向松弛度差异<3mm者33例(94.3%,33/35),3~5mm者2例(5.7%,2/35);轴移试验阴性34例(97.1%),阳性1例(2.9%)。根据IKDC检查标准,四股肌腱移植物组有29例(87.9%,29/33)、八股肌腱移植物组有34例(97.1%,34/35)为正常或者接近正常,Lysholm评分分别为(90.2±2.9)分和(97.3±1.7)分,两组比较差异有统计学意义(P<0.05)。结论关节镜下采用八股腘绳肌肌腱较采用四股腘绳肌肌腱双束重建前十字韧带能够明显提高膝关节稳定性。  相似文献   
78.
We used inferior pedicled composite multi-fractured osteoperiosteal flap (CMOF), our original and new surgical approach, to obliterate the mastoid cavity and reconstruct the external auditory canal (EAC) to prevent the open cavity problems. CMOF was used to obliterate the mastoid cavity and reconstruct the EAC in 24 patients (13 women, 11 men; age span 12–51 years) who underwent radical mastoidectomy to treat the chronic otitis media between 1998 and 2004. Small meatoplasty was done in all 24 patients to relive their aesthetical concerns. Temporal bone CT scanning was done to observe the neo-osteogenesis in the mastoidectomy cavity and the CMOF, and the EAC volume was measured postoperatively. All our patients were followed-up for 2 years. The epithelization of the new EAC in our patients was complete at the end of the second month. Cholesteatoma, granulation, and recurrence of osteitis did not occur in any of the patients. We saw the new bone formation filling the mastoid cavity in the postoperative temporal bone CT scanning images. The mean volume of the new EAC on the 24th month was 1.83 ± 0.56 cm3. We had an almost natural EAC, which owed its existence to the neo-osteogenesis that grows behind the CMOF, which we use to obliterate the mastoid cavity and to reconstruct the EAC.This technique, composite multi-fractured osteoperiosteal flap, was presented in the symposium of Gulhane Military Medical Academy on otology and audiology, 15–18 September, 2005, Antalya, Turkey.  相似文献   
79.
The concept of partial rupture of the anterior cruciate ligament (ACL) has been confirmed by arthroscopic examination and palpation. We present a prospective study of 43 patients who were diagnosed arthroscopically as suffering from a partial rupture of the ACL by the same surgeon. The patients followed a rehabilitation protocol and were examined by an independant observer after 5 years. Twenty-five patients had a stable knee, whereas 18 eventually suffered a complete ACL rupture. ACL partial rupture is easily recognizable with arthroscopy, but the quantity and state of the still intact fibres is difficult to assess. Received: 20 April 1996 Accepted: 17 December 1996  相似文献   
80.
目的 为提高额颞部除皱术的效果 ,延长有效时间 ,从理论与实际观察探讨额颞部老年化改变形成的原因 ,并采用相应的手术术式进行矫正。方法 肿胀麻醉下 ,通过颞部发际缘切口入路 ,在颞深筋膜浅面剥离 ,内达颞肌前缘及眶外缘 ,下达颧弓上缘 ,后达耳屏前线。额部切口入路在帽状腱膜下剥离 ,下达眶上缘外至颞线后至枕外隆突。口腔内上颊龈沟入路在颧骨及颧弓骨膜下剥离。上述各剥离区域相互贯通 ,最后将颞区皮瓣上提 ,并将颞浅筋膜与颞深筋膜缝合固定。结果 本组共 32例 ,术后眉外侧平均上提 8mm ,鼻唇沟变浅 ,获随访的 7例为术后 3~2 4个月 ,除皱效果满意。结论 本术式旨在通过广泛剥离解除了额颞部皮肤筋膜上提的羁绊 ,同时减少上面部降肌的作用 ,相对增强提肌的作用 ,再辅以筋膜及皮肤上提固定达到除皱的目的 ,效果确实、可靠、安全、持久。  相似文献   
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