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81.
The purpose of this study is to evaluate the relationship between the magnitude of knee laxity and posterior instability at different knee flexion angles and clinical disability in isolated posterior cruciate ligament (PCL) deficient patients. Knee laxity at 20° and 70° of knee flexion were evaluated using KT-2000 arthrometer, and the posterior instability at 20°, 45° and 90° of flexion were evaluated using stress radiography. We assessed the differences in the knee laxity and the tibial translation between isolated PCL deficient knees and normal knees, and between the patients with giving-way during activities of daily living (ADL) and without giving-way. There were statistical differences in the knee laxity and the tibial translation at all knee flexion angles between the PCL deficient knees and normal knees. The magnitude of the knee laxity at 20° of flexion measured with KT-2000 arthrometer was significantly larger in the patients with giving-way than those in the patients without giving-way although there was no significant difference in the tibial translation at 70° between the two groups. The tibial translation in both medial and lateral compartments at 20° and 45° measured with stress radiography were significantly larger in the patients with giving-way than those in the patients without giving-way although there was not significant difference at 90° between the two groups. These results suggested that the magnitude of the knee laxity and the posterior tibial translation at shallow knee flexion angles would be related to giving-way during ADL in isolated PCL deficient patients.  相似文献   
82.
膝关节后外侧结构的解剖与MRI研究   总被引:4,自引:0,他引:4  
目的 改进膝关节后外侧结构MRI定位方法,提高后外侧结构损伤的诊断准确率。方法 解剖膝关节标本,辨认后外侧各结构起止点及走行,明确它们之间的解剖关系。以注水的输液器缝合标记各结构进行MRI扫描,测量各结构在矢状面和冠状面上与腓骨颈长轴之间的夹角。按照这些角度定位扫描正常膝关节,观察各结构在MRI中完整显示的情况。结果 (1)测得矢状面上腓侧副韧带和胴肌腱关节囊内部分与腓骨颈长轴的夹角分别为(11.5±1.7)°和(39.5±6,4)°冠状面上胴肌腱关节囊外部分和胴腓韧带与腓骨颈长轴夹角为(39.5±3.9)°和(31.9±3.9)°。(2)腓侧副韧带在11°后斜冠状位1个层面上完整显示占90%,胴肌腱关节囊内部分在40°后斜冠状位1个层面上完整显示占80%,胭肌腱关节囊外部分在内斜40°矢状位1个层面上完整显示占90%,胭腓韧带在外斜30°矢状位1个层面上完整显示占90%。此外,胴腓韧带在11°后斜冠状位1个层面上完整显示的占75%,股二头肌腱和髂胫束在常规冠状面均能够很好显示.结论 选择完整显示腓骨茎突和腓骨颈的冠状面和矢状面为基准面,按照后外侧各结构与腓骨颈长轴所呈角度进行定位,层厚2mm的MR扫描能很好地显示膝关节后外侧解剖结构。  相似文献   
83.
膝关节粘连关节镜下射频汽化消融松解术   总被引:2,自引:0,他引:2  
目的总结关节镜下射频汽化消融技术在膝关节粘连松解术中的应用体会及短期临床效果。方法2002年1月至2005年6月,对各种原因所致膝关节粘连32例行关节镜下射频汽化消融粘连松解术。依据关节造影所示粘连程度分为3组:A组18例髌上囊粘连,单纯做髌上囊及内外侧沟上方成形。B组8例主要为关节间隙粘连,在做髌上囊及侧沟粘连带清理后加髁问窝清理,加压屈曲膝关节,切断内外侧关节间隙粘连带。C组6例膝关节大部分粘连,进镜操作困难者加做髌骨内外上极小切口,先做髌上囊钝性分离造成腔隙,然后镜下进一步松解。松解配合推拿。射频汽化电极点凝行关节腔内彻底止血。术后不留置引流,第2天开始被动结合主动膝关节加压屈伸功能锻炼。结果A组术前屈曲35°~75°,术后3周115°~125°,平均改善78°;B组术前屈曲40°~60°,术后3周95°~120°,平均改善72°;C组术前屈曲25°~45°,术后3周90°~110°,平均改善64°。术后关节腔内无积血,关节及其周围组织肿胀轻。结论关节镜下射频汽化消融松解膝关节粘连出血少,创伤小,松解效果可靠,可避免以往方法的不利因素,对于髌上囊、侧沟或关节间隙粘连的患者尤为适用。  相似文献   
84.
Although magnetic resonance imaging is the most accurate imaging method of evaluating the anterior cruciate ligament, several plain radiographic signs suggestive of anterior cruciate ligament injury have been described. Plain radiographs also play an important role in evaluating anterior cruciate ligament reconstruction.  相似文献   
85.
对335例膝骨关节炎(OA)临床分析结果显示:膝OA患病率随着增龄而增加,且病情也随之加重,部分可合并骨质疏松,并以女性多见。本组体块指数(BMI)平均值为26.1,有12%为肥胖,61%为超重。提示BMI过高是引起膝OA原因之一。以往临床不太重视的体征如骨摩擦音、骨关节肿胀等体征十分常见。因此,作好细致的体检,对提高本病的临床诊断有着重要意义。无论X线或MRI均可见病膝胫股关节的内侧部OA发生率较外侧部严重,可能与胫骨上端内翻、致承重线内移有关。MRI在显示关节结构以及早期诊断方面均优于X线。根据MRI特点可将膝OA分为三种类型,即①单纯型,②软组织型,③骨型。这将有利于提高对膝OA异质性的认识,达到治疗个体化的目的。  相似文献   
86.
Synovial haemangioma of the knee: a frequently misdiagnosed lesion   总被引:2,自引:0,他引:2  
Objective The objective of this study was to assess the contribution of magnetic resonance (MR) imaging in the diagnosis and surgical planning of five cases of synovial haemangioma of the knee.Patients and Methods The clinical, radiological and arthroscopic features of five pathologically proven synovial haemangiomas of the knee were retrospectively reviewed.Results A diagnostic delay, on average of 8 years, had occurred in four of the cases. Plain films were unremarkable, except for one case with arthropathy mimicking haemophilia, Arteriography, performed in three patients, was normal in one. CT, performed in three patients, showed the lesion, but the extent of the latter was better demonstrated with MR imaging. Synovial haemangiomas had a high signal intensity on T2-weighted images, without any extensive mass effect. Fibrofatty septa within the lesion were observed in three cases and muscular and/or fatty invasion in two. Arthroscopy allowed diagnosis of the lesion in two cases, but showed only non-specific synovitis in another two.Conclusion This study emphasizes the valuable contribution of MR imaging in the diagnosis and surgical planning of synovial haemangiomas.  相似文献   
87.
膝关节半月板撕裂的磁共振诊断:附61例关节镜对照分析   总被引:2,自引:0,他引:2  
目的:比较分析半月板撕裂的MRI表现和关节镜所见,明确半月板撕裂MRI成像的作用和价值。材料和方法:对一组61例(68膝)MRI资料的影像学特征与关节镜所见作对照分析,MRI半月板内异常高信号影的判断采用Lotysch提出的分级标准。结果:MRI对半月板损伤的诊断敏感性为95%,特异性为88%,关节镜符合率为92%。MR的Ⅲ级信号与关节镜所见半月板撕裂具有高度相关性,其中Ⅲ级信号仅见于一层和见于一层以上者分别与半月板撕裂的对应关系有显著差别。病变信号发生部位及其与半月板特定表面的关系对诊断结果无影响。结论:MRI对膝关节半月板撕裂的诊断极有价值,半月板内Ⅲ级信号是诊断半月板撕裂的可靠征象,而当Ⅲ级信号影仅见于一层时,诊断须慎重。  相似文献   
88.
龚高进  范海泉  江洋  黄海汛 《西部医学》2023,35(6):837-842+847
探讨锌指蛋白440(ZNF440)在膝关节(Knee)骨性关节炎(OA)软骨细胞损伤和退化变性病理生理学中的作用。方法 Knee软骨中分离人软骨细胞,分为对照组、Knee OA组、ZNF440-GFP(绿色荧光蛋白)组、ZNF440-siRNA组和Scriptaid组。通过免疫组化和Western blotting测定ZNF440在Knee OA软骨中的表达。用ZNF440-GFP过表达和ZNF440-siRNA转染细胞,并给予白细胞介素-1β(IL-1β)刺激。分别用qPCR和WB检测分解代谢、合成代谢和凋亡相关标志物的mRNA和蛋白表达水平。生物信息学分析有可能抑制ZNF440表达的化合物。结果 与对照组相比,ZNF440在Knee OA软骨中的表达有所增加(P<0.05);ZNF440过表达明显增加基质金属蛋白酶(MMP)13和PARP p85的表达,并降低COL2A1表达(P<0.05);siRNA敲除ZNF440可部分逆转IL-1β刺激诱导的人Knee OA软骨细胞的分解代谢和细胞凋亡(P<0.05)。通过生物信息学分析和验证实验,确定Scriptaid是一种有可能下调ZNF440表达的化合物。Scriptaid处理可降低OA软骨细胞中ZNF440的表达,同时降低过表达ZNF440的人Knee OA软骨细胞中MMP13和PARP p85的表达(P<0.05)。结论 ZNF440在人Knee OA软骨中的表达明显增加,可能通过调节细胞中炎症、分解代谢和凋亡标志物的表达参与软骨退行性机制。此外,Scriptaid可降低ZNF440的表达,并抑制其在OA软骨细胞中的破坏作用  相似文献   
89.
BackgroundPatellofemoral joint cartilage defects are difficult to treat due to their unique thickness and topography.PurposeTo report the postoperative outcomes of patients age 21 and younger treated with particulated juvenile allograft cartilage (PJAC) for full-thickness cartilaginous defects of the patellofemoral joint. The primary aim was to report surgical outcomes and complication rates, as well as return to sport activity. A secondary aim was to provide objective scores of defect restoration by magnetic resonance imaging (MRI) assessment.MethodsA retrospective review of all PJAC cases conducted between 2012 and 2019 at a single tertiary care urban musculoskeletal institution was conducted. Patients 21 years old or younger with minimum clinical follow up of 1 year and postoperative MRI at a minimum of 6 months were included. Cartilage restoration by MRI was independently assessed using the International Cartilage Repair Society’s (ICRS) standardized system.ResultsThirty four patients, 36 knees, were included, with mean age 16.1 ± 3.1 years old. Return to sport rate among patients who participated in a sport preoperatively was 100%. On independent MRI assessment, two thirds of defects achieved an overall grade of normal or nearly normal, while 28 patients (78%) had majority defect fill. Primary graft failure occurred in two cases and one patient experienced a surgical complication.ConclusionRestoration of patellofemoral chondral defects in young patients with particulated juvenile allograft results in satisfactory short-term outcomes and postoperative MRI appearance, along with high rates of return to sport and low rate of complications and graft failure.What is known about the subject: Patellofemoral joint cartilage defects are difficult to treat due to their unique thickness and topography. Several cartilage restoration techniques are available, but these rarely achieve the same mechanical properties as native hyaline cartilage. PJAC is a cell-based technique that has demonstrated promise since its introduction in 2007.What this study adds to existing knowledge: This series of patients adds the largest single cohort of pediatric and adolescent patients who receive PJAC for defects of the patellofemoral joint. Surgeons treating patients in this age group should be aware of every technique, and their respective outcomes.  相似文献   
90.
BackgroundKnee osteoarthritis (KOA) is increasingly prevalent in North American society. The significant societal burden it represents makes it essential to promote and target new treatments in earlier phases of the disease. Among others, subchondroplasty is a newly documented technique using calcium phosphate injection targeting the osteochondral lesions preceding KOA, also known as Bone Marrow Lesions (BMLs). This article aimed to review the existing literature on clinical and radiological outcomes of subchondroplasty in the treatment of BMLs in KOA.MethodA systematic review was performed using PubMed, Embase, Medline and Cochrane Database of Systematic Reviews. Studies on calcium phosphate injections into BMLs for KOA and its clinical and radiological outcomes were screened and reviewed by independent evaluators.ResultsAfter screening, ten articles were included, totaling 540 patients. Follow-up ranged from 6 months to 7 years. Overall, the procedure showed significant functional and quality of life improvement, as well as pain relief, as shown by Patients-Reported Outcomes Measures (PROMs). There were very few complications reported, the most important being leakage of calcium phosphate outside the targeted site. Conversion rate to total knee arthroplasty (TKA) ranged from 14 % to 30 % at 2 years post-procedure. Long term radiological outcomes have been poorly documented.ConclusionsSubchondroplasty is a promising avenue for the treatment of KOA. However, quality evidence is still required before any real conclusions and practical management guidelines can be drawn. Prospective, randomized studies with a control group and a rigorous assessment of long-term clinical and radiological outcomes are recommended.  相似文献   
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