Imaging of the knee joint with emphasis on magnetic resonance imaging

The knee joint is frequently affected by trauma as well as degenerative and inflammatory disorders, involving the internal structures (i.e. ligaments, menisci, cartilage, synovial membrane) and the adjacent bones. Plain radiographs represent an indispensable basis for diagnosis. For further analysis magnetic resonance imaging (MRI) has become the method of choice, and has widely replaced computed tomography, arthrography and stress examinations. Extensive experience has been accumulated in MRI of the knee joint in recent years. In addition, advances in MRI technology have had a major impact on diagnostic accuracy. In this paper, diagnosis of various lesions of the knee joint, such as meniscal and ligamental injuries, aseptic necrosis, lesions of the hyaline cartilage, occult fractures and inflammatory lesions will be discussed. Offprint requests to: M. F. Reiser     

膝关节后内侧结构生物力学意义及损伤的MRI表现

目的:分析膝关节后内侧结构的解剖、生物力学特点及临床意义;阐述膝关节后内侧结构的MRI正常及损伤后表现;进行后内侧结构损伤MRl分级.方法:回顾分析87例后内侧结构、以及其他相关损伤的MRI所见.结果:本组87例后内侧结构损伤,Ⅰ级损伤29例,Ⅱ级47例,Ⅲ级11例;合并交叉韧带损伤34例(39%),内侧半月板后角撕裂...     

胫骨平台骨折及膝关节附属结构损伤的MRI诊断

目的评价胫骨平台骨折合并膝关节附属结构损伤的MRI表现.资料与方法 27例胫骨平台骨折病例经X线平片检查后作MRI扫描,分析不同类型胫骨平台骨折所合并的膝关节附属结构损伤的MRI形态学表现.结果 MRI能准确显示骨折所合并的膝关节附属结构的损伤性病变,包括关节软骨断裂、半月板撕裂和移位、侧副韧带和肌腱的撕裂、关节腔脂肪血性积液等,其中双髁骨折引起的损伤最为严重,撕脱骨折引起的损伤较轻.结论 MRI能准确诊断胫骨平台骨折合并的膝关节附属结构损伤,应作为膝关节外伤的常规检查手段.     

膝关节骨与韧带急性损伤的MRI研究

目的:探讨MRI检查中急性膝关节骨损伤与韧带损伤之间的合并关系以及临床应用价值。方法:38例急性膝部骨损伤病人,行MRI重点观察STIR序列的损伤情况。骨损伤分为显性骨折(X线检查可见)与隐性骨损伤(X线检查未见异常),韧带损伤包括撕裂与完全断裂。结果:38例共45处骨损伤,包括显性骨折28处(73%)、隐性骨损伤(骨挫伤)17处(44%)。84%病例的骨损伤累及胫骨。86%的病例合并多韧带损伤,最常累及内侧副韧带、前交叉韧带与后交又韧带,74%的损伤韧带非邻近骨损伤部位。结论:急性膝部骨损伤最常累及腔骨,常合并多韧带损伤,但韧带损伤多不靠近骨损伤部位。MRI脂肪抑制序列能直观地显示韧带的撕裂与完全断裂,且能发现相当多的隐性骨损伤病例。     

膝关节弯曲位3T 磁共振成像的临床分析

目的：探讨3 TMR膝关节弯曲位成像的优越性。方法58例临床怀疑膝关节损伤的患者行3 TMRI检查,58例患者同时行常规成像和弯曲位成像。采用双盲法对2种方法得出的常规图像和弯曲位图像按照韧带显示程度和对病变的显示能力进行评价。结果58例膝关节常规成像中,前后交叉韧带同时完整显示19例,显示韧带损伤25例（前交叉韧带损伤9例,后交叉韧带损伤16例）。58例膝关节弯曲位成像中,前后交叉韧带同时完整显示45例,Wrisberg韧带完整显示7例,显示韧带损伤28例（前交叉韧带损伤11例,后交叉韧带损伤16例,Wrisberg 韧带损伤1例）。结论膝关节弯曲位成像的交叉韧带、Wrisberg韧带和病变显示程度明显优于常规方法。     

Imaging of the postoperative knee: normal and pathologic findings

Surgical management of lesions of the knee has exponentially increased over the last several years. MRI plays a major role in postoperative follow-up and evaluation of patients with residual symptoms. Familiarity with the different surgical procedures and potential complications and knowledge of normal and abnormal postoperative MRI findings are essential for evaluation of the postoperative knee. The main purpose of this article is to review the postoperative imaging features of ligaments, menisci and cartilage of the knee joint since these MRI features may lead the surgeon to consider repeat surgery.     

Magnetic resonance imaging in menisco-ligamentous lesions. Comparison with arthroscopy. Apropos of 37 cases

Results of magnetic resonance imaging of 37 cases of lesions of meniscus and ligaments of knee are reported and compared with arthroscopy findings. Use of MRI appears to be an excellent non-invasive diagnostic method, with current major indications in acute knee injuries and for evaluation of chronic laxity. It also allows guidance of surgical procedures. In the future, MRI should replace the more aggressive arthrography, this with a relatively short examination time, since sagittal section imaging in TI permits detection of the majority of lesions.     

Does marathon running cause acute lesions of the knee? Evaluation with magnetic resonance imaging

An investigation was conducted into whether running a marathon causes acute alterations in menisci, cartilage, bone marrow, ligaments, or joint effusions, which could be evaluated by magnetic resonance imaging (MRI). Twenty-two non-professional marathon runners underwent MRI of the knee before and immediately after running a marathon. Lesions of menisci and cartilage (five-point scale), bone marrow, ligaments (three-point scale), joint effusion, and additional findings were evaluated and a total score was assessed. Before the marathon, grade 1 lesions of the menisci were found in eight runners, and grade 2 lesions in five runners. After the marathon, an upgrading from a meniscal lesion grade 1 to grade 2 was observed in one runner. Before the marathon, grade 1 cartilage lesions were found in three runners, and grade 2 lesions in one runner, all of which remained unchanged after the marathon. Before and after the marathon, unchanged bone marrow edema was present in three runners and unchanged anterior cruciate ligament lesions (grade 1) were seen in two runners. Joint effusions were present in 13 runners in the pre-run scans, slightly increased in four runners after the marathon, and newly occurred in one runner after the marathon. A total score comprising all knee lesions in each runner showed an increase after the marathon in two runners, whereas no runner showed an improvement of the radiological findings (Wilcoxon signed-rank test, P>0.05). The evaluation of lesions of the knee with MRI shows that marathon running does not cause severe, acute lesions of cartilage, ligaments, or bone marrow of the knee in well-trained runners. Only subtle changes, such as joint effusions or increased intrameniscal signal alterations, were imaged after running a marathon.     

High-energy knee dislocations

High-energy knee dislocations are severe injuries that usually involve tears of at least 3 of the 4 major ligaments of the knee. Severe capsular, neurovascular, integument, meniscal, and tendinous injuries are common. Patients with high-energy knee dislocations often have sustained remote orthopaedic injuries and other organ-system trauma that may preclude early, aggressive treatment of the torn knee ligaments. Popliteal artery injury occurs in high-energy knee dislocations, and if not quickly recognized and treated, may result in amputation. The range and complexity of injury patterns in high-energy knee dislocations requires the orthopaedic surgeon to use a variety of treatment options to reduce mortality, prevent amputation, and maximize the final functional outcome of the injured limb. Treatment of the injured knee ligaments often must be delayed because of the patient's other injuries. A spanning external fixator applied across the knee joint has been an excellent method for maintaining reduction of the knee before definitive surgical treatment of the knee ligaments.     

膝关节韧带损伤的MRI诊断

目的：分析膝关节韧带损伤的MRI表现及诊断价值。资料与方法：回顾性分析22例经手术或关节镜检查证实的膝关节韧带损伤的MRI资料。结果：22例膝关节损伤患者中，共有37条韧带损伤，MRI检出其中的34条，其敏感性为91．9％，准确性为95．5％。交叉韧带损伤的MRI表现为韧带连续性中断，局灶或弥漫性肿胀，信号强度增加及断端移位。侧副韧带损伤的MRI表现为韧带连续性中断和／或韧带肿胀增粗，信号升高。结论：MRI是诊断膝关节韧带损伤的理想的非创伤性检查方法。     

Application of MR imaging for internal derangement of the knee (orthopedic surgeon' view)

Magnetic resonance imaging is a noninvasive imaging modality with clear contrast and superior spatial resolution. These characteristics are especially useful for detecting pathology of the soft tissue of the knee joint, such as the menisci, ligaments and articular cartilage, which are difficult to diagnose using plain X-ray examination. MRI has become one of the first choice diagnostic modalities for the internal derangement of the knee joint, and is generally replacing some invasive arthrographic or arthroscopic examination. Pathology of the articular cartilage cannot yet be depicted clearly by MRI. We expect further development of the spatial resolution of MRI to make possible the detection of chondral lesions more clearly and precisely in the near future.     

Magnetic Resonance Imaging of Cruciate Ligament Injuries of the Knee

The anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) are important stabilizers of the knee. These ligaments are commonly injured in sports and motor vehicle accidents. An accurate diagnosis of cruciate ligament injuries is vital in patient care. Magnetic resonance imaging (MRI) can diagnose cruciate ligament injuries with high accuracy. The imaging diagnosis should be based on primary signs, although the secondary signs are sometimes useful, particularly in chronic cases. The detection of associated injuries of other structures of the knee, including menisci, collateral ligaments, cartilage, and bone, are also important. Accurate interpretation of the MRI examination requires a meticulous MRI technique, knowledge of the imaging anatomy, and understanding of the lesion appearance. This pictorial essay reviews the MRI appearance of normal and injured cruciate ligaments. Mechanisms of injury, primary and secondary MRI signs, and associated abnormalities are discussed.     

膝关节退行性骨关节病的MRI表现

目的 :探讨MRI对膝关节退行性骨关节病的诊断价值。方法 :对手术、关节镜或临床证实的 2 1例 2 6个膝关节退行性骨关节病的MRI表现进行回顾性分析。结果 :MRI能较好地显示膝关节病变的关节软骨、半月板、韧带、骨质等改变 ,还能对关节软骨、半月板损伤和退变进行分级 ,明显优于传统X线检查。结论 :MRI检查能清楚显示退行性骨关节病的病变特点和严重程度 ,为临床选择合适的治疗方案提供了依据。     

MRI在膝关节损伤诊断中的应用价值

目的:通过膝关节损伤MRI影像的分析,确定其诊断价值及意义。材料和方法:本文收集了自1992年以来我院所检查的42例膝关节损伤患者,52个膝关节成像。其中男性34人;女性8人,各年龄组以30～40岁组最多。损伤以前交叉韧带和外侧半月板损伤者多见,分别占总损伤数的20％及30％。损伤又以左膝多见,占总数的61％。结果:MRI能较明确地显示膝关节的半月板、关节软骨、韧带、滑膜及骨质的改变,明显地比CT所能看到的层次多,对软组织的损伤显示清晰。结论:只要正确地应用不同序列及切层方向、厚度等技术,可清晰地显示其信号特征,从而能确定其损伤部位、程度。     

膝关节骨关节炎的磁共振成像

目的：探讨膝关节骨关节炎患者运用MRI发现膝关节各结构病变的价值以及与疼痛症状之间的关系。方法：搜集本院已确诊或拟诊为膝关节骨关节炎的患者28例（男12例,女16例,平均年龄61.4岁）共31个膝关节为研究对象,运用主诉疼痛分级法对疼痛程度进行分级。运用1.5T磁共振仪对上述膝关节行多序列扫描,观察各研究对象磁共振图像中各种病变的出现率。运用统计软件（SPSS13.0;SPSS,Chicago,Ⅲ）分别计算本研究对象中上述关节各种结构病变的出现率,并行多组独立样本间Fisher精确检验比较不同疼痛程度患者组间出现上述征象的差别,以P〈0.05为差异有显著性意义。结果：所有31例膝关节骨关节炎患者中磁共振成像显示关节软骨异常、半月板异常、前交叉韧带异常、软骨下骨骨髓水肿样改变、骨赘形成、滑膜增厚、关节积液的出现率分别为37.1%、32.3%、38.7%、45.2%、100%、15.1%和67.7%。其中轻、重度疼痛患者两组间有无关节积液及关节积液Ⅰ级和Ⅱ级的出现率差异均有显著性意义（P=0.004,0.001）。结论：磁共振可对膝关节骨关节炎患者行全关节各结构的评价,能很好地显示关节多方面的病理改变。患者的疼痛症状与关节积液有关。     

膝关节损伤的MRI诊断及其临床价值

目的：研究膝关节损伤的MRI特点、病理基础、诊断价值及其临床意义。材料与方法：回顾性分析42例经手术病理证实的膝关节损伤的MRI资料。结果：42例膝关节损伤患者中，半月板撕裂34例，MRI表现为黑色的半月板内出现异常信号，其中延伸至关节面（26例）；“水桶把手”样撕裂（4例）；半月板变形缩小（4例）。前交叉韧带损伤28例，MRI表现为黑色条索状无信号韧带影中出现异常信号，呈不连续弯曲波浪状、斑片状或团块状。后交叉韧带损伤4例。其他改变：半月板囊肿4例，侧副韧带损伤18例，关节积液38例，骨折7例。结论：MRI对膝关节损伤的诊断具有重要的临床意义，可为制定正确的治疗方案提供客观而详细的依据。     

膝关节韧带损伤的MRI诊断

目的:探讨膝关节韧带损伤的MRI表现及诊断价值。方法:36例临床怀疑膝关节损伤的患者于关节镜及手术前行MRI检查,以关节镜结果作为金标准,前瞻性分析膝关节韧带损伤的MRI表现及诊断价值。结果:关节镜证实前交叉韧带损伤21例,其中完全撕裂15例,部分撕裂6例,后交叉韧带损伤12例,正常患者15例。MRI诊断前交叉韧带损伤的敏感度为95.2%,特异度为80%,准确度为88.9%;诊断后交叉韧带损伤的敏感度为100%,特异度为95.8%,准确度为97.2%。结论:MR1是诊断膝关节韧带损伤的理想检查方法,具有较高的临床应用价值。     

军事训练致膝关节损伤的关节镜下诊断和治疗

目的探讨关节镜对军事训练所致膝关节损伤的诊断及其治疗效果。方法回顾性分析我院2002年1月—2009年10月收治的171例军事训练所致膝关节损伤官兵临床资料,总结军事训练所致膝关节损伤的特点。所有病例均行膝关节MRI检查,并在关节镜下行手术治疗或关节探查清理。对比MRI检查结果的准确率。术前、术后均对所有病例行膝关节Lysholm评分及主观评价。结果本组病例随访时间10～22月,Lysholm评分术前(42.1±3.7)分,术后为(84.3±2.3)分。无因手术而症状加重及发生血管神经损伤及感染等并发症。结论关节镜既有诊断价值又是治疗手段,关节镜检查可全面评估膝关节的损伤程度,微创治疗膝关节军事训练疾患,相比其他治疗手段具有明显的优越性。     

不同地区新兵在高海拔地区体能训练致膝关节损伤的MRI研究

 目的 对比研究不同海拔地区新兵在高海拔地区体能训练各阶段致膝关节损伤的MRI表现特点,为减少其发生提供理论依据。方法 120名新兵,分为低海拔组和高海拔组,在新训的第1、2、3个月行右膝关节MRI扫描,观察各阶段的膝关节骨质(骨髓、骨皮质、关节软骨)、半月板、韧带、软组织及关节腔损伤情况。结果 (1)低海拔组新兵第1阶段骨髓水肿及关节腔积液检出率(85.0%、65.0%)高于高海拔组新兵检出率(46.7%、33.3%;P<0.01);低海拔组新兵第2阶段骨髓水肿及关节腔积液检出率(91.7%、86.7%)高于高海拔组新兵检出率(71.7%、65.0%;P<0.01);(2)低海拔组新兵第2、3阶段半月板损伤检出率(16.7%、20.0%)高于同阶段高海拔组新兵检出率(1.7%、3.3%;P<0.01);(3)两组新兵各阶段骨皮质、关节软骨、韧带及软组织损伤检出率差异均无统计学意义。结论 低海拔地区新兵新训期膝关节损伤率高于高海拔地区,应该根据新兵来源地区的海拔高度制定正确施训策略和防护措施,以减少其发生。     

Bildgebungsstrategie bei Kniegelenkverletzungen

Injuries of the knees are common. The Ottawa knee rule provides decisional support to determine whether radiographs are indicated or not. With the use of ultrasound it is possible to detect defects of the extensor ligaments and the anterior cruciate ligament. Furthermore, it is possible to detect indirect signs of an intra-articular fracture, e.g. lipohemarthrosis. In complex fractures, e.g. tibial plateau fractures, further diagnostic procedures with multislice computed tomography (CT) are needed for accurate classification and preoperative planning. Multislice CT with CT angiography enables three-dimensional reconstruction of the knee and non-invasive vascular imaging for detection of vascular injury. Magnetic resonance imaging (MRI) is the gold standard for detection of occult fractures and injuries of the ligaments and menisci. Higher field strengths can be used to improve the diagnostics of cartilage lesions. Virtual MR arthrography is superior to conventional MRI for detection of cartilage lesions especially after meniscus surgery.