膝关节前交叉韧带撕裂的低场强MRI诊断

膝关节前交叉韧带（ACL）是膝关节重要但最易受损伤的稳。定结构之一。MRI具有较高的软组织对比度,是前交叉韧带损伤最重要的无创性诊断手段。MRI对ACL损伤的诊断主要依靠直接征象,间接征象作为补充。本研究复习125例经关节镜证实的膝关节损伤MRI资料,对其中34例ACL损伤的MRI征象进行分析,总结MRI在ACL损伤中的诊断价值。     

前交叉韧带撕裂的MRI诊断

目的:研究膝关节前交叉韧带撕裂的MRI表现。方法:回顾分析30例经关节镜证实的前交叉韧带撕裂MR图像及40例完好的ACL,分析其直接及间接征象的特征。结果:在评价的直接征象中,ACL不连续和ACL走行异常均具有相对高的诊断敏感性、特异性;在评价的间接征象中,后交叉韧带角、Blumensaat角、后交叉韧带指数、半月板后移征、“对吻性”骨挫伤、胫骨前移位等6个征象具有相对高的特异性,后交叉韧带角、Blumensaat角具有较高的敏感性。结论:ACL损伤的直接征象为诊断主要依据,ACL损伤的间接征象具有辅助诊断意义。     

膝关节韧带损伤MRI诊断的评价(附36例分析)

目的：探讨膝关节韧带损伤的MRI表现及诊断价值。方法：分析36例经手术或关节镜证实的膝关节韧带损伤患者的MRI材料，重点分析了前交叉韧带(ACL)损伤的MRI表现。结果：前交叉韧带部分性撕裂为T1WI、T2WI、T2^*像上韧带内信号均增高，但纤维束仍保持其连续性和完整性；完全性撕裂的直接征象为韧带连续性中断、增粗或扭曲变形；看不到正常的ACL，于附着处出现一团块影，T2WI韧带内呈弥漫高信号；间接征象有胫骨前置和后交叉韧带变形等。结论：ACL损伤在MBI上有一定的特点。MRI是诊断膝关节韧带损伤的一种有效的无创性检查方法。     

MRI多征象分析对前交叉韧带损伤的诊断价值

目的：评价MRI对前交叉韧带（anterior cruciate ligament,ACL）损伤多种征象的诊断价值。方法：回顾分析了128个膝关节的MR图像。全部膝关节均行关节镜检查,其中52个膝关节的ACL损伤,另外76个膝关节的ACL显示完整。在不告知关节镜结果的前提条件下,2名影像科医生共同对ACL损伤的5个直接征象和10个间接征象进行评价,意见不一致时协商解决差异。结果：在评价的5个直接征象中,ACL不连续和ACL走行异常具有相对高的诊断敏感性和特异性;在评价的10个间接征象中,大多数具有相对高的特异性和低的敏感性,其中空髁间窝征、Notch征、外侧半月板后角裸露征、PCL指数、冠状面PCL单层显示等征象特异性较高。结论：ACL损伤的直接征象为诊断的主要依据,以ACL不连续和ACL走行异常具有较高的诊断价值;ACL损伤的间接征象具有辅助诊断意义,其中空髁间窝征、Notch征、外侧半月板后角裸露征、PCL指数、冠状面PCL单层显示等征象最具有诊断价值。     

膝关节急性前交叉韧带撕裂的常见MRI征象分析

目的 :分析膝关节急性前交叉韧带(anterior cruciate ligament,ACL)撕裂的MRI征象,提高对ACL撕裂的术前诊断和评估能力。方法:回顾性分析117例经关节镜或手术证实急性ACL撕裂患者的临床及影像学资料,分析其MRI征象。结果:117例MRI直接征象主要为ACL纤维中断或部分不连续、弥漫性增粗并信号增高、走行异常、胫骨附着处撕脱骨折;间接征象主要为胫、股骨外侧髁的"对吻性"骨挫伤或骨折、后交叉韧带曲率增大、胫骨前移位、内侧副韧带损伤、内侧半月板撕裂。评估分析5种MRI直接征象得出,ACL走行异常具有相对高的诊断敏感度和特异度;5种MRI间接征象均诊断特异度高而敏感度低。结论 :MRI直接征象能较准确地诊断急性ACL撕裂,并评估其撕裂程度,可作为主要诊断依据;而MRI间接征象特异度较高、敏感度相对较低,不能作为主要诊断依据,但对明确诊断具有较大帮助,可作为辅助诊断依据。     

高场磁共振扫描前交叉韧带损伤分析

高场磁共振成像广泛应用于膝关节的临床检查,磁共振成像（MRI）良好的软组织分辨率、多平面成像及其无创伤性,已成为诊断前交叉韧带（ACL）损伤的重要方法及首选手段^[1]。本研究对434例前交叉韧带损伤的MRI成像与关节镜对比结果、ACL损伤在MRI表现多个征象及ACL损伤程度进行浅要分析探讨。对提高前交叉韧带损伤的诊断的准确率非常有帮助。现总结报告如下。1资料与方法1.1一般资料:回顾分析我院2007年5月至2013年12月MRI扫描观察的膝关节前交叉韧带损伤病例434例,其中男性340例,女性94例,年龄13⁸2岁,平均46.9岁。右膝关节     

前交叉韧带断裂的MRI征象研究

目的 研究前交叉韧带(ACL)断裂的MRI表现,探讨其直接征象和间接征象的产生机制及诊断价值.方法 本组男37例,女3例;年龄16～49岁,平均33岁.急性期断裂28例,慢性期断裂12例,均经关节镜检查和手术证实.采用1.5 T西门子MRI扫描仪,SE或TSE序列T1、12、质子压脂、medic和横断位、矢状位、冠状位多方位成像.组织3名高年资医师进行回顾分析,对ACL断裂的MRI直接征象和间接征象进行统计分析.结果 ACL断裂4|D例中完全性断裂35例,部分断裂5例.急性期断裂的28例直接征象分别为信号中断或不连续24例(86%),信号不均匀18例(64%),韧带肿胀增厚10例(36%);而慢性期断裂的12例分别韧带增厚11例(92%),信号中断或不连续9例(75%),信号不均匀7例(58%),其中韧带增厚征象主要见于慢性期的ACL断裂(P＜0.01).完全性断裂的35例中,28例(80%)发生在中段,上端、下端发生率低;5例部分断裂均发生在前内侧束.ACL断裂的间接征象中,后交叉韧带(PCL)"7"字变形34例(85%);半月板外露26例,其中外侧半月板外露16例(62%);骨损伤15例,其中胫骨撕裂骨折8例(53%);关节间隙增宽9例,其中78%属于慢性断裂;胫骨前移23例(57%).本组40例中,术前正确诊断37例,正确率为92%;3例部分断裂术前未能诊断,漏诊率为8%.结论 根据ACL断裂的直接征象和间接征象,结合外伤史,术前诊断比较容易.     

半月板桶柄样撕裂的MRI表现

目的 探讨半月板桶柄样撕裂的MRI征象. 资料与方法 对经关节镜证实的半月板桶柄样撕裂56例(58侧)患者的MRI表现进行研究. 结果 领结残破征21膝,空领结征28膝,双前交叉韧带征6膝,双后交叉韧带征19膝,双半月板前角征11膝,前角异常肥大征5膝,双半月板后角征16膝,后角异常肥大7膝,后角残破征19膝,厚饼征6膝,半月板分离移位征53膝.合并膝关节囊积液58膝、股骨(或胫骨)挫伤36膝、内侧副韧带损伤6膝、前交叉韧带损伤5膝、后交叉韧带损伤9膝、关节软骨损伤13膝、骨梗死2膝. 结论 空(残)领结征、后角残破征、双后交叉韧带征及半月板分离移位征提示半月板桶柄样撕裂.     

后交叉韧带MRI相关指标在前交叉韧带损伤诊断中应用的研究进展

前交叉韧带(ACL)的主要功能是维持膝关节稳定, 防止胫骨平台前移。ACL损伤的占比已超过膝关节损伤的50%, 若诊治不及时, 将增加半月板和软骨等结构继发性损伤的风险, 造成膝关节慢性疼痛及退变。虽然大部分ACL损伤可通过其在MRI上的直接征象确定, 但对一些复杂情况及ACL部分撕裂的辨别仍不够明确, 继而影响治疗策略。ACL损伤后, 膝关节内部解剖关系的改变也会导致后交叉韧带(PCL)等其他结构在MRI上形态的改变, 这些间接征象可以辅助诊断ACL损伤。笔者就PCL MRI相关指标在ACL损伤诊断中应用的研究进展进行综述, 以期为临床决策提供参考和新思路。     

膝板股韧带附着区外侧半月板后角撕裂的MRI表现及诊断价值

目的 探讨膝板股韧带附着区外侧半月板后角（PHLM）撕裂的MRI表现及鉴别诊断价值。 方法 选取2012年12月至2018年6月因前交叉韧带（ACL）损伤在南通市通州区中医院就诊的35例膝板股韧带附着区PHLM撕裂患者作为观察组,搜集同期30例ACL损伤但非PHLM撕裂患者作为对照A组,另选取同期例行体检的30名健康者作为对照B组。3组受试者均行膝关节MRI检查,观察3组受试者的MRI表现。分别应用χ 2检验、单因素方差分析和t检验分析膝关节MRI征象的发生率、膝关节周围结构的损伤情况及膝关节线状高信号影显示的层数和长度,并采用受试者工作特征（ROC）曲线分析鉴别诊断PHLM真、假性撕裂的效能。 结果 观察组患者在MRI矢状面和横断面图像上均表现为明显的PHLM周缘部线状高信号,矢状面上可连续检出（5.75±1.38）层（称“连续线征”）,横断面上自内向外延伸（15.06±5.02）mm（称“拉链征”）,与对照A组、B组比较差异均有统计学意义（F=43.231、36.113,均P<0.05）。以“连续线征”和“拉链征”作为阳性标准,MRI诊断膝板股韧带附着区PHLM撕裂的灵敏度为85.71%、特异度为95.00%、准确率为91.58%。 结论 膝板股韧带附着区PHLM撕裂在MRI上有明显的征象,辅以“连续线征”和“拉链征”进行鉴别诊断,可明显提升诊断效果。     

外伤性膝关节前外侧韧带损伤的MR影像特征及相关性分析

目的探讨外伤所致膝关节前外侧韧带损伤病人的MR影像特征,并分析其与前交叉韧带撕裂、外侧半月板撕裂及骨挫伤的相关性,为深入研究前外侧韧带对膝关节稳定性的作用提供可靠依据。方法回顾性分析2016年1月—2017年2月间因外伤进行膝关节MRI检查的320例病人(共321膝)的影像资料。采用美国GE公司生产的Signa HDe 1.5 T MR扫描设备,分别行膝关节斜矢状面T1WI、质子密度加权成像(PDWI)和冠状面、横断面PDWI扫描。根据前外侧韧带的完整性和损伤部位对所有病人进行分类统计。采用独立性卡方检验对前外侧韧带撕裂与前交叉韧带撕裂、外侧半月板撕裂及骨挫伤的相关性进行分析。结果全部病人膝关节MR影像均可显示前外侧韧带,显示率为100%。151/321膝(47.0%;95%CI为41.6%~52.5%)存在前外侧韧带损伤,其中累及胫骨部、股骨部及半月板部的分别为97膝、96膝及65膝。前交叉韧带撕裂158膝,外侧半月板撕裂98膝,股骨外侧髁挫伤58膝,外侧胫骨平台挫伤71膝,分别与前外侧韧带撕裂具有相关性(均P0.001)。结论 MRI检查可以很好地显示前外侧韧带解剖及其损伤情况。膝关节前外侧韧带损伤与前交叉韧带撕裂、外侧半月板撕裂及膝外侧骨挫伤具有相关性。     

Indirect signs of anterior cruciate ligament injury on SPET: comparison with MRI and arthroscopy

Indirect signs of anterior cruciate ligament (ACL) injury on magnetic resonance imaging (MRI) include bony contusions in the lateral femoral condyle and the posterior portion of the lateral tibial plateau. This study was undertaken to assess the value of single photon emission tomography (SPET) in the diagnosis of ACL injury by examining the uptake pattern in the distal femur and the proximal tibia. Thirty-five patients were examined using SPET, MRI and arthroscopy. Seventeen patients were found to have ACL tears on arthroscopy. The duration of symptoms was 4 days to 10 years (mean 26.4 months). MRI and SPET images were analysed retrospectively without information from arthroscopic examination. Radionuclide uptake in the lateral femoral condyle and the posterior lateral tibial plateau was considered an indirect sign of ACL injury on SPET. We evaluated the diagnostic value of indirect signs of ACL injury obtained on SPET by comparing these findings with arthroscopic and MRI results. Fifteen of 17 patients with ACL injury showed indirect signs on SPET. The sensitivity, specificity, positive predictive value and negative predictive value for indirect signs of ACL injury were 88%, 56%, 65% and 83% on SPET and 59%, 94%, 91% and 71% on MRI, respectively. However, despite the higher sensitivity of indirect signs on SPET than on MRI, the overall diagnostic value of MRI is better than that of SPET. In the clinical setting, indirect signs of ACL injury may be of value in interpreting incidental findings on SPET.     

MRI of anterior cruciate ligament injuries and associated findings in the pediatric knee: changes with skeletal maturation

OBJECTIVE: The objective of our study was to evaluate the MRI characteristics of anterior cruciate ligament (ACL) injuries and associated findings relative to skeletal maturity. We also contrast the frequency of findings in this younger population to adult data. MATERIALS AND METHODS: Eighty-two consecutive knees with an MRI report diagnosis of ACL injury (partial tear, sprain, or complete tear) or tibial spine avulsion fracture imaged over 4 years were retrospectively reviewed. Patients were grouped by degree of skeletal maturity as determined from the MR images. The examinations were reviewed for the type of ACL injury, secondary imaging findings, and associated knee injuries. Findings were correlated to skeletal maturity, and frequencies were compared with adult data. RESULTS: ACL injuries were more common in boys in the skeletally immature group, but more common in girls in the skeletally mature group (p = 0.03). Tibial spine avulsion fractures were most common in skeletally immature patients (p < 0.01), whereas complete tears of the ACL were most common in skeletally mature patients. Associated injuries were less common in the skeletally immature group, but this trend did not reach statistical significance. Most secondary signs of ACL injuries occurred at similar rates in all groups with frequencies similar to those reported in adults. CONCLUSION: ACL injuries in skeletally immature patients are seen more often in boys. Tibial avulsion fractures and partial tears are more common in younger, less rigid skeletons that may absorb the forces of trauma. As children mature, complete ACL tears and associated injuries occur in frequencies approaching those patterns seen in adults. Similarly, skeletally mature girls are affected more often than mature boys.     

Partial and complete tear of the anterior cruciate ligament

PURPOSE: To analyze MR direct and indirect signs for knees with anterior cruciate ligament (ACL) partial or complete tear. MATERIAL AND METHODS: According to documented MR direct and indirect signs for ACL tear, we retrospectively reviewed the incidence of those signs in 15 partial ACL tear and 17 complete ACL tear patients. The findings were also compared with duration of injury (less or more than 6 weeks, as acute or chronic stages). RESULTS: A residual straight and tight ACL fiber in at least one pulse sequence was more frequently detected in partial ACL tears. The empty notch sign, a wavy contour of ACL, bone contusion at lateral compartment and lateral meniscus posterior horn tear were significantly more frequently seen in complete tear cases. The posterior cruciate ligament angle in chronic complete ACL tear cases (109 degrees +/-20 degrees ) had a tendency to be less than in chronic partial ACL tear cases (119+/-18 degrees ). CONCLUSION: The empty notch sign, a wavy ACL, bone contusion, and posterior horn of lateral meniscus tears are suggestive of a complete ACL tear. A residual straight and tight ACL fiber seen in at least one image section is a helpful sign to diagnosis of partial ACL tear. In the acute ACL injury stage, a focal increase of the ACL signal intensity is more suggestive of a partial ACL tear.     

An isolated rupture of the posterior cruciate ligament results in reduced preoperative knee function in comparison with an anterior cruciate ligament injury

Purpose

To investigate differences in preoperative knee function (Knee Injury and Osteoarthritis Outcome Score, KOOS), the time period from injury to surgery, and associated injuries when comparing primary isolated posterior cruciate ligament (PCL) and primary anterior cruciate ligament (ACL) reconstructions.

Methods

Isolated primary ACL and PCL reconstructions registered in the Norwegian National Knee Ligament Registry from 2004 through 2010 were included (n = 71 primary PCLs and 9,649 primary ACLs). Linear regression analysis was used to evaluate the preoperative KOOS subscale values.

Results

The preoperative KOOS in the PCL group (n = 71) and ACL group (n = 9,649) was significantly different for the subscales symptoms (mean difference, ?8.4; 95 % CI: ?12.8 to ?4.0), pain (mean difference, ?15.9; 95 % CI: ?20.3 to ?11.4), activities of daily living (mean difference, ?12.9; 95 % CI: ?17.4 to ?8.4), sport and recreation (mean difference, ?15.9; 95 % CI: ?22.6 to ?9.3), and quality of life (mean difference, ?7.9; 95 % CI: ?12.4 to ?3.5). The primary isolated PCL-reconstructed knees had a median time from injury to surgery of 21 months in comparison with 8 months for ACL injuries. The ACL-injured knees had more associated injuries (meniscus and full-thickness cartilage lesions) than the PCL-injured knees.

Conclusion

Surgically treated knees with an isolated rupture of the PCL exhibited worse knee function preoperatively compared with knees with an isolated ACL injury; in addition, the delay to surgery was longer. Meniscal lesions were found more frequently in ACL-injured knees.

Level of evidence

Prospective cohort study, evidence Level I.     

Reconstruction of the anterior cruciate ligament with the iliotibial band autograft in patients with chronic knee instability

We performed combined internal and external anterior cruciate ligament (ACL) reconstruction with the iliotibial band autograft in 169 consecutive patients with chronic ACL insufficiency who were followed up for 24-61 months. Of these, 155 (91%) agreed to an additional independent observer follow-up after 24-92 months. Eight patients (5%) had sustained a rerupture/elongation of the graft and were operated on again; nine (6%) had sustained a tear of the contralateral ACL. Knee function and activity increased after the reconstruction. Lysholm scores improved from median 81 preoperatively to 99 at follow-up and Tegner scores from median 4 to 7. At follow-up 97 (71%) were active at the same level as prior to injury. In 17 of the 40 patients (12%) dropping to a lower activity level this was due to knee problems. The side-to-side difference in anterior-posterior knee laxity was more than 3 mm in 18 knees (13%) and more than 5 mm in 3 knees (2%). Including eight reruptures, this results in a "stability" failure rate of 8.8%. The overall IKCD rating showed normal knee function in 88 (73%) and nearly normal knee function in 30 (25%). Anterior knee pain was present in 14 (10%) of the patients at follow-up. Patients with isolated ACL injury had higher Lysholm scores and Tegner scores than patients with associated injuries. No clinical signs of varus knee development were seen. Of the 155 patients 94% would have the procedure repeated if necessary with the knowledge that they have today. The combined internal and external iliotibial band procedure can restore knee stability and function in the majority of chronic ACL-insufficient knees.     

A comparison of acute anterior cruciate ligament examinations. Initial versus examination under anesthesia

The preoperative examination, the examination under anesthesia, and the findings at surgery were compared for acutely injured knees that were found at surgery to have anterior cruciate ligament (ACL) tears. The pivot shift was initially positive in only 35% of the knees; however, under anesthesia 98% were positive. The Lachman test was initially positive in 99% of the knees, and under anesthesia, 100%. The anterior drawer sign was present initially in 70% of the knees, and under anesthesia this increased to 91%. Of the 37 patients with isolated ACL tears, only 20 (54%) had initially positive anterior drawer signs. In the knees in which secondary restraints to anterior-posterior motion were injured, this percentage increased to 69% in medial meniscus injury, 82% in lateral meniscus injury and 89.5% in rupture of the medial collateral ligament (MCL). The Lachman test seems relatively unaffected by associated ligamentous or meniscal injuries, but the end point in the Lachman test is absent in all complete ACL tears. The pivot shift phenomenon, which was demonstrable in 98% of patients when tested under anesthesia, may be diminished when there is a MCL injury or absent in partial ACL tears. Experience in performing the Lachman test and in appreciating the quality of the end point will give the examiner a high degree of accuracy in making the diagnosis of an ACL tear without resorting to anesthesia, arthroscopy, or arthrography in most patients.