Posterior longitudinal ligament status in cervical spine bilateral facet dislocations

Objective It is generally accepted that cervical spine bilateral facet dislocation results in complete disruption of the posterior longitudinal ligament. The goal of this study was to evaluate the integrity of numerous spine-stabilizing structures by MRI, and to determine if any associations between injury patterns exist with respect to the posterior longitudinal ligament status.Design Retrospective case series.Patients A retrospective review was performed of 30 cervical spine injury subjects with bilateral facet dislocation. Assessment of 1.5T MRI images was carried out for: intervertebral disc disruption, facet fracture, and ligamentous disruption. Statistical analyses were performed to evaluate for associations between various injury patterns and posterior longitudinal ligament status.Results The frequency of MRI abnormalities was: anterior longitudinal ligament disruption (26.7%), disc herniation or disruption (90%), posterior longitudinal ligament disruption (40%), facet fracture (63.3%) and disruption of the posterior column ligament complex (97%). There were no significant associations between injury to the posterior longitudinal ligament and other structures. Compared to surgical reports, MRI was accurate for determining the status for 24 of 26 ligaments (three of three anterior longitudinal ligament, seven of nine posterior longitudinal ligament, and 14 of 14 posterior column ligament complex) but generated false negatives in two instances (in both MRI showed an intact posterior longitudinal ligament that was torn at surgery).Conclusions In contradistinction to the existing concept, the posterior longitudinal ligament can remain intact in a substantial proportion of hyperflexion injuries that produce bilateral cervical facet dislocation. Posterior longitudinal ligament integrity is not associated with any other injury pattern related to the anterior longitudinal ligament, intervertebral disc or facet fracture.     

Acute osteochondral injuries of the hip

Acute osteochondral injuries of the hip are rare in the absence of associated dislocation. A series of cases is presented in which these injuries were sustained after relatively minor trauma to the hip. Radiologic studies revealed evidence of mild hip dysplasia and, in one case, an osteochondral fracture of the right femoral head. Scintigraphy revealed the fracture and unexpected uptake in the acetabulum, which was subsequently confirmed as being due to labral tears or acetabular osteochondral injuries. In addition, the scan showed evidence of a possible avulsion-type injury of the iliofemoral ligament, suggesting the mechanism of subluxation.     

急性颈椎外伤的MRI诊断

目的 分析急性颈椎外伤的MRI征象,评价MRI在急性颈椎外伤诊断中的价值及限度。方法收集急性颈椎外伤150例,均有MRI检查和X线平片,15例有CT片,采用14个参数进行分析记录。结果150例中MRI检出骨折51个,小关节脱位30个,椎体脱位35个;外伤性椎间盘突出40个,硬膜外血肿2例;脊髓损伤69例;脊髓受压迫20例;前、后纵韧带损伤21例;棘间韧带和黄韧带损伤15例;椎前血肿或水肿30例;椎旁和背侧软组织损伤40例;X线平片发现椎体骨折55个,椎体脱位35个;小关节脱位35例,附件骨折25个,椎前软组织肿胀20例。15例CT均发现骨折,小关节脱位,椎管狭窄。结论MRI在显示脊髓、韧带、椎间盘和软组织损伤方面优于CT和X线平片。MRI能全面反映颈椎各种损伤的病理特征,为评估颈椎稳定性提供充分的依据;MRI和X线片的骨折检出率没有明显差异,CT应该用于复杂的颈椎骨折检查。     

Bilateral asymmetric hip dislocation: case report and literature review

Simultaneous anterior and posterior hip dislocation is an unusual injury. A unique case is presented, consisting of bilateral asymmetric hip dislocation with associated femoral head, femoral shaft, and acetabular fractures resulting from a motorcycle collision. The mechanisms of injury, management, role of imaging, and complications of this injury complex are discussed, with a review of the relevant literature.     

New mechanism of the posterior elbow dislocation

Purpose

To suggest a new model on the most common kind of posterior elbow dislocation using MRI findings on acute elbow injuries.

Methods

Fifteen patients with simple elbow dislocation (Group A) and 19 patients sustaining pure ligament injuries (Group B) were enrolled in this study. Using MRI scans, bony contusion at radial head and posterior capitellum (lateral bone contusion) and medial aspect of the ulnohumeral joint (medial bone contusion) were investigated with the injury patterns of the collateral ligament and overlying muscles. In Group A, the injury patterns of the ulnar and lateral ulnar collateral ligaments were classified into distraction or stripping type; in Group B, into rupture or strain. Based on these findings, we speculated the injury mechanism of the elbow dislocation.

Results

In Group A, posterolateral (PL) dislocation was found in 12 cases of distractive ulnar collateral ligament type and stripping lateral ulnar collateral ligament type, where lateral bone contusion was found in 11 cases. Posteromedial (PM) dislocation was observed in only two cases of distraction type of the LUCL, where medial bone contusion was seen in two cases. In PL dislocation of the elbow joint, we always found more severe damage of soft tissue at the medial side of the elbow joint compared to the lateral side. Lateral bone contusion was speculated to be caused by bony abutment under pathologic forearm external rotation (PFER) and medial bone contusion, by bony abutment under varus stress. In Group B, the ulnar collateral ligament was more commonly injured than the lateral ulnar collateral ligament, and lateral bone contusion accompanied most cases.

Conclusion

PL dislocation is thought to start from the medial side in contrary to PM dislocation beginning at the lateral side. If the disengagement of the coronoid process is not completed due to the insufficient valgus/varus distraction, a coronoid fracture will develop at the same time as the elbow dislocation during PFER.     

MRI对急性膝关节骨挫伤的临床应用价值

目的：探讨MRI对急性膝关节骨挫伤的临床应用价值。方法：对117例X线平片显示阴性并行MRI检查的外伤性膝关节病例进行回顾性分析,MRI检查时间为外伤后2h．5天,重点观察股骨下端、胫腓骨上端及髌骨的骨质信号,前后交叉韧带、内外侧副韧带、内外侧半月板的完整性和信号情况。结果：急性外伤后骨挫伤的发生率为87．2％（102／117）,合并韧带损伤62例,半月板损伤49例,关节软骨损伤17例,隐性骨折21例。结论：急性膝关节外伤后骨挫伤的发生率较高,MRI能准确显示骨挫伤的部位、范围以及临近结构的损伤,对临床诊断、治疗具有重要意义。     

Capsular lesions with glenohumeral ligament injuries in patients with primary shoulder dislocation: magnetic resonance imaging and magnetic resonance arthrography evaluation

The glenohumeral ligaments are important structures for the stability of the shoulder. They are integrated parts of the capsule and are at risk to be injured in a traumatic shoulder dislocation. The aim was to examine the prevalence of capsular ligament lesions in the acute phase and at minimum 3 weeks' follow-up after first-time traumatic shoulder dislocation. Forty-two patients aged 16-40 years were included. All patients underwent computed tomography and magnetic resonance imaging (MRI) scans shortly after the injury and MR-arthrography (MRA) at follow-up. The median time from dislocation to MRI was 7 (range 2-14) days and to MRA 30 (range 21-54) days. We found capsular ligament lesions in 22 patients (52.4%) in the acute stage and in five patients (11.9%) at follow up. Nine patients (21.4%) had a humeral avulsion of the anterior glenohumeral ligament (HAGL lesion) on MRI. Three patients (7.1%) had this lesion at follow-up. The rate of HAGL lesions in the acute stage was higher than reported previously, but the prevalence at follow-up was in keeping with earlier published studies.     

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。     

MSCT、MRI联合运用在复发性肩关节前脱位Bankart病损中的应用价值

目的:探讨MSCT、MRI联合运用在复发性肩关节前脱位Bankart病损中的应用价值。方法:回顾性分析经临床、影像证实的复发性肩关节前脱位Bankart病损10例患者的MSCT、MRI表现,主要观察肩关节盂唇前方的CT、MRI改变。结果:10例中,CT发现肩关节盂前下份撕脱性骨折4例,MRI发现肩关节前下盂唇撕脱性骨折1例;MRI发现肩关节盂唇损伤10例,CT不能显示;CT发现合并Hill-Sachs损伤6例,MRI发现Hill-Sachs损伤8例;CT未能发现肱骨头骨挫伤3例;MRI发现肩袖损伤6例,Slap损伤1例。结论:MSCT、MRI能够相互补充,清晰显示Bankart病损及其他合并病变,为临床诊断及治疗提供更加充分的资料。     

骨挫伤的MRI表现及意义

目的:探讨骨挫伤的MRI表现及意义。方法:回顾性分析两年内1 050名患者中的86例骨挫伤病例的MRI表现。结果:骨挫伤常伴有其他结构损伤,以股骨及胫骨外侧髁骨挫伤最多见,其次为股骨及胫骨内侧髁骨挫伤;常伴有前后交叉韧带、内外侧副韧带、内外侧半月板损伤及创伤性滑膜炎。结论:MRI对骨挫伤及其他结构损伤的发现有重要的临床意义。     

CT detection of cortical fracture of the femoral head associated with posterior hip dislocation

Posterior dislocation of the femoral head is a common injury in automobile accidents and is frequently associated with fractures of the posterior acetabular rim. Fractures of the anterior cortex of the femoral head have not been described. One hundred sixty-four cases of posterior hip dislocation presenting consecutively to our shock trauma unit and emergency department during a 3-year period were evaluated with plain film radiology and CT. In 21 cases (13%), CT showed an anterior cortical fracture of the femoral head that could not be seen on plain radiographs. This injury is similar to the Hill-Sachs lesion of the humerus that results from anterior dislocation. The anterior cortical fracture was associated with fractures of the posterior acetabulum in 18 cases (86%). The anterior fracture is caused by impaction of the anterior femoral head against the posterior acetabular rim at the time of dislocation. We conclude that anterior cortical fracture of the femoral head is a common accompaniment to posterior acetabular dislocation.     

Posterior shoulder labrocapsular structures in all aspects; 3D volumetric MR arthrography study

Pathologies of the posterior labrocapsular structures of the shoulder joint are far less common than anterior labrocapsuloligamentous lesions. Most of these pathologies have been associated with traumatic posterior dislocation. A smaller portion of the lesions include posterior extension of superior labral anteroposterior lesions, posterior superior internal impingement, and damage to the posterior band of the inferior glenohumeral ligament. Labrocapsular anatomic variations of the posterior shoulder joint can mimic labral pathology on conventional MR and occasionally on MR arthrographic images. Knowledge of this variant anatomy is key to interpreting MR images and studying MR arthrography of the posterior labrocapsular structure to avoid misdiagnosis and unnecessary surgical procedures. In this article, we review normal and variant anatomy of the posterior labrocapsular structure of the shoulder joint based on MR arthrography and discuss how to discriminate normal anatomic variants from labrocapsular damage.     

Entrapment of the acetabular labrum following reduction of traumatic hip dislocation in a child

In traumatic hip dislocation, concentric reduction can be prevented by various causes. Soft-tissue interposition, such as entrapment of the acetabular labrum, is a rare but important cause of failed reduction of a hip. Early diagnosis of incomplete reduction due to interposition of soft tissue is important, because delayed treatment is associated with a greater incidence of avascular necrosis of the femoral head and early onset of osteoarthritis. This report describes a case of acetabular labral entrapment following reduction of traumatic hip dislocation in a child. The importance of CT and MRI in arriving at an early diagnosis is emphasized.     

Osteochondral impaction of the femoral head associated with hip dislocation: CT study in 35 patients

Chondral and osteochondral impactions are insults to articular cartilage and subchondral bone of the femoral head during hip dislocation. To evaluate the frequency and sites of femoral head impaction, we reviewed CT scans of 35 patients with hip dislocation (32 posterior and three anterior). Osteochondral impaction fractures were present in 20 (63%) of the 32 patients with posterior hip dislocation and in all three patients with anterior dislocation. In patients with posterior dislocation, the impaction occurred anteriorly in an arc between the 11-o'clock and 1-o'clock positions in all seven cases (100%) of right-sided dislocation and in eight (61%) of 13 cases of left-sided dislocation. Twelve (60%) of the 20 patients with femoral head impaction fracture underwent surgery; osteochondral impaction was substantiated in all 12. In those with anterior dislocation, osteochondral impaction occurred at the posterolateral aspect of the femoral head in an arc between the 4-o'clock and 5-o'clock positions. A high rate of osteochondral impaction after hip dislocation was detected in this series. Observing the site of femoral head impaction allows determination of the type of original dislocation. Alternatively, when the type of original dislocation is known, the site of femoral head impaction can be predicted.     

Articular cartilage injury of the posterior lateral tibial plateau associated with acute anterior cruciate ligament injury

Thirty-nine knees in 39 patients with recent anterior cruciate ligament (ACL) rupture (age 14–55 years; with a mean age of 22.8 years) were selected from our cases of ACL reconstruction from July 2005 to June 2006, to take part in a study on articular cartilage injury of the posterior lateral tibial plateau associated with acute ACL injury and on the correlation between bone bruises depicted on MRI and cartilage injury of the posterior lateral tibial plateau detected at arthroscopic ACL reconstruction. Using preoperative MRI, we evaluated whether there were bone bruises or not in the lateral compartment of the knee and divided them accordingly into two groups: the bone bruise positive group and the negative group. The differences in the proportions of the lateral meniscus (LM) tears and the cartilage injuries in the two groups were evaluated using Fisher’s exact probability test. Thirty-five cases out of 39 arthroscopic ACL reconstructions (89.7%) were regarded as bone bruise positive in the lateral compartment and four cases (10.3%) were regarded as negative. At arthroscopic ACL reconstruction, 33 cases (84.6%) had tears in the LM posterior horn, 34 cases (87.2%) had articular cartilage injuries in the lateral femoral condyle and 29 cases (74.3%) had articular cartilage injuries in the posterior lateral tibial plateau. From 35 bone bruise positive cases, 32 cases (91.4%) had tears in the LM posterior horn, 33 cases (94.3%) had articular cartilage injuries in the lateral femoral condyle and 28 cases (80%) had articular cartilage injuries in the posterior lateral tibial plateau. Of four bone bruise negative cases, one case (25%) had a tear in the LM posterior horn, articular cartilage injury of the lateral femoral condyle and of the posterior lateral tibial plateau. There was a statistically significant correlation between the proportion of bone bruise and cartilage injury of the lateral femoral condyle (P = 0.004), that of the posterior lateral tibial plateau (P = 0.04) and that of tears in the LM posterior horn (P = 0.008). This current study has demonstrated that we need to pay attention to cartilage damage of the posterior lateral tibial plateau as well as to posterior horn tears in LM, when acute ACL injury is shown. We also have to ensure that we follow the long-term progress of cartilage injuries, with the aim of preventing these injuries becoming osteoarthritis after ACL reconstruction.     

颈椎单侧关节突交锁的治疗选择

目的 探讨颈椎单侧关节突交锁的不同治疗方法选择.方法 32例颈椎单侧关节突交锁,行头颅牵引复位成功8例,其中3例维持牵引1个月后改行头颈胸石膏固定,余5例行前路减压植骨融合内固定术.23例牵引失败,其中14例行前路切开复位、椎间盘切除植骨融合内固定术;3例前路复位失败行椎间盘切除加椎体次全切除减压植骨内固定术,1例前路复位失败改行后路切开复位后再前方植骨内固定术;3例行后路切开复位侧块内固定植骨融合术,2例行后路切开复位减压、前路椎间盘切除减压植骨内固定术.1例由于漏诊,伤后8个月行前路减压植骨融合术.结果 平均随访18个月.发现颈椎不稳2例,均为仅行牵引复位,未做融合术者.颈前路手术者植骨块术后12周均获骨性融合.颈椎生理曲度及椎间隙高度恢复较好.无内固定并发症,亦无治疗中神经并发症.结论 下颈椎单侧关节突交锁的治疗需要综合考虑多方面的因素,包括是否伴有椎间盘损伤、是否合并后柱骨折、脊髓压迫及损伤情况.对伴有创伤性颈椎间盘突出的单侧关节突交锁者,前路减压复位稳定术是首选方法,对于不伴椎间盘突出者,可试行牵引复位或直接后路切开复位固定.     

高山滑雪运动踝关节急性期损伤MRI表现

目的:探讨高山滑雪运动(AS)踝关节急性期损伤MRI特点。方法:搜集27例AS运动踝关节急性损伤患者(共29个踝关节损伤)作为实验组;随机选取30例普通外伤踝关节患者(共30个踝关节损伤)作为对照组。采用3.0T MRI和相控阵线圈进行踝关节扫描。由2名放射科主治医师评估膝关节骨、软骨、韧带、肌腱等损伤。结果:实验组多结构联合损伤29(100%)个;对照组多结构联合损伤24(80.00%)个。MRI显示实验组内踝、外踝、胫骨滑车、距骨、跟骨、舟骨、骰骨挫伤/骨折分别为14、12、12、17、15、13、14个,对照组分别为7、5、5、9、8、6、6个;实验组内侧胫距关节软骨、外侧胫骨关节软骨、距下关节软骨、距跟舟关节软骨、距骰关节软骨损伤分别为16、15、14、12、13个,对照组分别为8、6、7、5、5个;实验组三角韧带、距腓前韧带、距腓后韧带、跟腓韧带、下胫腓前韧带、下胫腓后韧带损伤分别为16、17、13、16、15、12个,对照组分别为8、9、6、9、7、5个;实验组拇长屈肌肌腱、趾长屈肌肌腱、胫骨后肌肌腱、腓骨长短肌肌腱、拇长伸肌肌腱,趾长伸肌肌腱、胫骨前肌肌腱损、跟腱损伤分别为14、15、14、14、14、13、14、15个,对照组分别为7、7、6、7、6、6、7、8个。两组损伤发生率差异具有统计学意义(P均<0.05)。实验组关节软骨损伤0、Ⅰ、Ⅱ、Ⅲ、Ⅳ级分别为75、33、16、11、10个,对照组分别为119、12、7、6、6个;实验组韧带损伤0、Ⅰ、Ⅱ、Ⅲ级分别为68、58、31、17个,对照组分别为124、31、13、12个;实验组肌腱损伤0、Ⅰ、Ⅱ、Ⅲ级分别为105、82、31、14个,对照组分别为171、45、15、9个。两组损伤程度差异具有统计学意义(P均<0.001)。实验组常见多个解剖部位、多发性骨挫伤/骨折,而对照组常见直接撞击部位的骨挫伤/骨折。实验组关节软骨常表现≥Ⅱ级损伤,而对照组软骨损伤常表现Ⅰ级损伤。实验组多表现为多条韧带联合损伤,以Ⅱ级损伤居多;对照组以单条韧带损伤为主,以Ⅰ级损表现居多。实验组常表现多条肌腱Ⅰ级损伤,对照组常表现单条Ⅰ级损伤。结论:滑雪运动踝关节损伤为骨髓、软骨、韧带及肌腱的联合损伤,正确认识滑雪运动踝关节急性期损伤的MRI表现,对早期诊断、踝关节功能恢复有重要意义。     

膝关节Ⅴ型骨挫伤的MRI诊断及临床意义

目的 评价MRI对膝关节Ⅴ型骨挫伤的诊断价值及临床意义.方法 从1672例急性膝关节外伤的MRI资料中筛选出具有Ⅴ型骨挫伤的患者,分析其膝关节MRI表现.结果 Ⅴ型骨挫伤发生率2.6%(43/1672),表现为同时累及髌骨内下缘及股骨外髁前外缘的异常信号,在T_1WI上表现为低信号,在T_2WI上表现为等或稍高信号,在压脂PDWI上为高信号,在矢状面、冠状面及横断面上均可以敏感发现.MRI上显示骨折9例,软骨损伤29例,髌骨向外半脱位或脱位27例.髌骨内侧支持带损伤37例,在横断面上显示最佳并能进行分级.结论 MRI能准确显示膝关节Ⅴ型骨挫伤,对髌骨一过性脱位的诊断和治疗有重要意义.在MR检查中发现Ⅴ型骨挫伤时应加作髌骨横断面检查,以评估髌骨内侧支持带的损伤情况.     

难以复位合并小关节绞锁的下颈椎脱位的手术治疗

目的探讨难以复位合并小关节绞锁的下颈椎脱位的手术治疗。方法12例下颈椎脱位患者，经三维CT检查证实8例有单侧小关节绞锁，4例双侧小关节绞锁；MRI检查发现，12例患者均有椎间盘损伤，其中4例为椎间盘破裂，8。例为椎间盘突出；经颅骨牵引后未能复位的12例患者，Ⅰ期行前路减压、后路解锁融合固定、前路融合固定手术。结果12例患者术后原有神经症状未加重，小关节绞锁及脱位均得到解除和复位；术后1—2周内大部分(10／12)患者神经功能按改良Frankel分级上升：1例A级→B级(2例A级无变化)，B级→C级2例，C级→D级3例，C级→E级3例，D级→E级1例。住院时间9—19d，平均14d。结论前路减压、后路解锁融合固定、前路融合固定术是治疗难以复位合并小关节绞锁的下颈椎脱位的理想方法。     

Shoulder MR arthrography: which patient group benefits most?

OBJECTIVE: We sought to compare the diagnostic accuracy of conventional MRI versus MR arthrography of the shoulder in the assessment of high-performance athletes (professional baseball players) and to compare our findings in these patients with the conventional MRI and MR arthrographic findings in an age-matched control group of nonprofessional athletes. MATERIALS AND METHODS: Conventional MRI and MR arthrographic examinations of the shoulder in 20 consecutive professional baseball players with shoulder pain were reviewed retrospectively by two musculoskeletal radiologists in consensus. These interpretations were compared with retrospective consensus interpretations of conventional MRI and MR arthrographic examinations of the shoulder obtained in a control group of 50 consecutive nonprofessional athletes with shoulder pain. MR images were assessed for full- or partial-thickness supraspinatus tendon tears, superior labral anteroposterior (SLAP) tears, and anterior or posterior labral tears. RESULTS: In the 20 consecutive professional athlete patients, two full-thickness and six partial-thickness undersurface supraspinatus tendon tears were seen on MR arthrography but not seen on conventional MRI as well as six SLAP tears, two anterior labral tears, and one posterior labral tear. Three patients had both SLAP tears and full- or partial-thickness supraspinatus tendon tears. Of 14 patients with findings on MR arthrography that were not seen on MRI, 11 had arthroscopic correlation. In all 11, arthroscopic findings confirmed findings on MR arthrography. In the group of 50 nonprofessional athlete patients, five had additional findings on MR arthrography not seen on conventional MRI: two anterior labral tears, two partial-thickness supraspinatus tendon tears, and two SLAP tears. One patient had both a partial-thickness supraspinatus tendon tear and a SLAP tear seen on MR arthrography. The five patients with additional findings on MR arthrography had arthroscopy. In all five, arthroscopic findings confirmed the findings on MR arthrography. CONCLUSION: MR arthrography is considerably more sensitive for detection of partial-thickness supraspinatus tears and labral tears than conventional MRI. MR arthrography showed injuries in addition to those seen on conventional MRI in 14 of 20 patients in the high-performance athlete group. These results suggest high-performance athletes may be a subgroup of patients for whom MR arthrography yields considerably more diagnostic information than conventional MRI.