Association between extrinsic and intrinsic carpal ligament injuries at MR arthrography and carpal instability at radiography: initial observations

PURPOSE: To retrospectively compare the presence or absence of carpal instability on radiographs with the findings of magnetic resonance (MR) arthrographic evaluation of intrinsic and extrinsic ligament tears in patients with chronic wrist pain. MATERIALS AND METHODS: The institutional review board approved this study and did not require informed consent. Signs of carpal instability were assessed on static and dynamic radiographs of the wrist obtained in 72 patients (24 female, 48 male; mean age, 36 years; age range, 14-59 years) with posttraumatic wrist pain. MR arthrography was subsequently performed. Two musculoskeletal radiologists independently analyzed the radiographs and MR images. Each intrinsic and extrinsic ligament was individually evaluated for the presence of a ligament tear. The extent of the tear also was recorded. Interobserver agreement regarding MR arthrographic findings was tested by calculating kappa statistics. Statistical comparison between radiography and MR arthrography was performed by using the Fisher exact test. RESULTS: Twenty-five triangular fibrocartilage complex, 18 (five partial, 13 complete) scapholunate ligament, and 25 (10 partial, 15 complete) lunotriquetral ligament tears were visualized. Twenty-two (all complete) extrinsic ligament tears were detected: two radial collateral ligament, 10 radioscaphocapitate ligament, and 10 radiolunotriquetral ligament tears. Interobserver agreement regarding intrinsic and extrinsic ligament tear detection at MR arthrography was excellent (kappa = 0.80). Nineteen patients had evidence of carpal instability on radiographs. Fourteen (52%) of 27 patients with at least one complete intrinsic lesion had no sign of carpal instability. On the other hand, the association of scapholunate ligament and/or lunotriquetral ligament and extrinsic ligament tears was significantly correlated (P < .001) with carpal instability at radiography. CONCLUSION: The presence or absence of carpal instability on radiographs depends on the association between intrinsic and extrinsic ligament tears-even partial ones-rather than on the presence of intrinsic ligament tears alone, even when the tears are complete.     

Wrist Trauma: More Than Bones

Acute and subacute wrist trauma predominantly consist of fractures of the distal radius in elderly patients and most frequently carpal fractures (scaphoid, followed by triquetrum and hamatum) and avulsion fractures of the ulnar styloid in younger patients, especially in sports-related injuries but also in work activities. The initial radiographs may miss the fractures and result when untreated in complications as nonunion, osteonecrosis, and degenerative osteoarthritis.Fractures of the distal radius and of the scaphoid may be associated with ligament injuries, most frequently the scapholunate complex, which are often overlooked at the emergency department. Patients without osseous injuries may present intrinsic and extrinsic ligament tears that may lead to carpal instability when they are clinically and/or radiologically missed.Therefore, in acute and subacute setting, computed tomography may be helpful for the detection of subtle fractures, and magnetic resonance imaging, for the early diagnosis of occult fractures and ligament injuries.     

Carpal ligamentous disruptions and negative ulnar variance

Negative ulnar variance is a condition in which the ulna is relatively shorter than the radius at the carpus. It was found in 21% of 203 normal wrists. We have observed an increased incidence (49%) of this anomaly in patients with carpal ligamentous instabilities (dorsiflexion instability, palmar flexion instability, scapholunate dissociation with rotary luxation of the scaphoid, and lunate and perilunate dislocations). While the reasons for this association have yet to be adequately delineated, the presence of a negative ulnar variant may serve as an impartial clue to the presence of ligamentous instability. Many carpal instabilities present with subtle radiographic findings requiring careful evaluation of radiographs. Patients with negative ulnar variance and histories suggestive of ligamentous instability should undergo careful radiologic evaluation to assure early diagnosis of carpal disruption.     

Carpal ligamentous laxity with bilateral perilunate dislocation in Marfan syndrome

A case of persistent bilateral perilunate dislocation unrelated to trauma in a patient with Marfan syndrome is discussed. This finding is believed to be a manifestation of the generalized ligamentous laxity occurring in this disorder. Radiographs of eight additional Marfan syndrome patients failed to demonstrate similar carpal instability. Because some carpal derangements are dynamic events, stress views or wrist fluoroscopy may be necessary to demonstrate unsuspected carpal instability in Marfan patients.     

Instability of the carpal bones]

The understanding of carpal instability and their radiological signs are based on a knowledge of the anatomy and complex physiology of the wrist. This article successively deals with the physiological anatomy, radiological technique, normal static and dynamic radiological features, radiographic signs of various types of instability and therapeutic principles.     

Traumatic injuries: imaging of spinal injuries

Severe (high-energy) spinal injuries are common sequelae of acute traumas. The task of radiology is to establish the radiological diagnosis, classify it, judge stability and instability and lead further radiological evaluation in cases of non-agreement between the radiological diagnosis and the clinical (neurological) findings. While skeletal abnormalities are best diagnosed with spiral CT and to a lesser degree with plain-film radiographs, soft tissue lesions, such as cord injuries or ligament ruptures, are best outlined with emergency MRI. The classification of fractures depends on fracture (trauma)-biomechanics and location. All these efforts are necessary to get the best clinical outcome for the patient.     

Carpal instability

This review addresses the pathoanatomical basics as well as the clinical and radiological presentation of instability patterns of the wrist. Carpal instability mostly follows an injury; however, other diseases, like CPPD arthropathy, can be associated. Instability occurs either if the carpus is unable to sustain physiologic loads (“dyskinetics”) or suffers from abnormal motion of its bones during movement (“dyskinematics”). In the classification of carpal instability, dissociative subcategories (located within proximal carpal row) are differentiated from non-dissociative subcategories (present between the carpal rows) and combined patterns. It is essential to note that the unstable wrist initially does not cause relevant signs in standard radiograms, therefore being “occult” for the radiologic assessment. This paper emphasizes the high utility of kinematographic studies, contrast-enhanced magnetic resonance imaging (MRI) and MR arthrography for detecting these predynamic and dynamic instability stages. Later in the natural history of carpal instability, static malalignment of the wrist and osteoarthritis will develop, both being associated with significant morbidity and disability. To prevent individual and socio-economic implications, the handsurgeon or orthopedist, as well as the radiologist, is challenged for early and precise diagnosis.     

腕关节X线侧位三角形阴影改变对腕骨脱位的诊断价值

目的 探讨腕关节侧位三角形阴影的改变对腕骨脱位的诊断价值.方法 68例腕骨脱位患者均摄有腕关节正侧位片,通过对腕关节正常影像学表现及腕骨脱位的影像学资料进行观察分析,对比腕骨脱位患者腕关节侧位三角形阴影的改变.结果 68例腕骨脱位患者中,腕关节侧位三角形阴影有改变65例,占95.59％,无改变3例,占4.41％.其中单纯腕骨脱位17例,腕关节侧位三角形阴影有改变15例,无改变2例;腕骨周围脱位32例,腕关节侧位三角形阴影有改变31例,无改变1例;经腕骨腕骨脱位或腕骨周围脱位19例,腕关节侧位三角形阴影均发生改变.结论 腕关节侧位三角形阴影的改变对绝大多数腕骨脱位的诊断有重要价值,对腕骨侧向脱位的诊断无意义.     

创伤性寰枢椎不稳的几个问题

创伤性寰枢椎不稳可导致脊髓受压甚至患者死亡。不稳的原因是寰枢椎和齿状突骨折及寰横韧带撕裂。本组报告52例．其中33例为齿状突骨折，8例寰枢爆炸性骨折，4例枢椎弓骨折，7例韧带损伤及1例寰枕脱位。新鲜损伤采用非手术治疗，陈旧性者则行寰椎后弓切除和枕颈融合术，或单行枕颈融合术，本文就其临床和X线诊断作了讨论。     

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.     

Diagnostic value of MR arthrography in detection of intrinsic carpal ligament lesions: use of cine-MR arthrography as a new approach

Twenty-five patients with chronic wrist pain and a preliminary diagnosis of carpal instability were examined with conventional MR imaging and MR arthrography with single compartment intra-articular injection. A new cine-MR arthrography technique, with image acquisition at every 5 s during intra-articular injection, was performed in 17 subjects. The purpose of this study was to determine the diagnostic value of MR arthrography in ligamentous lesions of the wrist and to assess the value of cine-MR arthrography in comparison with arthroscopy and/or surgery. Magnetic resonance arthrography, a semi-invasive technique, increased the diagnostic accuracy of intrinsic carpal ligament injuries. Cine-MR arthrography can be considered as a promising technique especially for the evaluation of lunatotriquetral and scapholunate ligament injuries of the wrist. Received 6 December 1995; Revision received 29 November 1996; Accepted 24 February 1997     

Rotatory palmar subluxation of the lunate in post-traumatic ulnar carpal translocation

Post-traumatic ulnar carpal translocation is a rare, severe ligamentous injury to the wrist. Radiologic findings include widening of the radiocarpal joint space at the radial styloid process and ulnar displacement of the carpus. Less than 50% of the lunate articulates with the radius in the neutral position; the lunate is tilted dorsally with palmar subluxation due to a ruptured radioscapholunate (RSL) ligament. This malposition should be called rotatory palmar subluxation of the lunate (RPSL), by analogy to rotatory subluxation of the scaphoid (RSS). In contrast to dorsiflexed intercalated segment instability (DISI), in RPSL the RSL ligament is ruptured and, in the majority of cases, the scapholunate ligament remains intact. A prompt diagnosis should lead to successful treatment.     

Wrist fractures: what the clinician wants to know

With the recent improvements in diagnosis and treatment of distal radius and carpal injuries, the hand surgeons' expectations of relevant radiologic interpretation of imaging studies are heightened. Conventional radiographic examinations, as well as more sophisticated and invasive studies, have important roles in the evaluation of wrist fractures and dislocations. On the basis of physical examination results and the mechanism of injury, the onus is on the examining surgeon to pinpoint potential sites of bone or ligament disruption. After this evaluation, appropriate imaging studies appropriately performed and interpreted will help direct treatment and improve outcome with greater clarity and certainty.     

Multidirectional instabilities and hyperlaxity of the shoulder]

Multidirectional instability is an unusual entity which is frequently missed in the context of unstable shoulder. The diagnosis of this condition may be difficult and is based on demonstration of basic anatomical lesions, usually acquired: capsular distension and damage to the inferior glenohumeral ligament responsible for the inferior component of the instability. Despite a suggestive clinical history, the positive diagnosis is based on a very detailed clinical and radiological examination, performed under general anaesthesia if necessary, in order to define the preferential direction of instability. Conventional and CT arthrography are of undeniable diagnostic and therapeutic value in the context of assessment. First-line treatment should be conservative. When surgery is indicated, it may consist of a combination of bone grafts and capsulorraphy, as described by C.S. Neer.     

腕骨脱位的X线平片及40层螺旋CT诊断比较

目的 探讨腕骨脱位X线平片及多层螺旋CT的影像学表现,并对两者的检出情况进行比较,以提高对腕骨脱位的诊断水平,减少漏诊误诊.资料与方法对2006年8月-2009年11月共21例腕骨脱位病人的X线平片、多层螺旋CT薄层扫描及容积再现(VR)三维重组和多平面重组(MPR)影像进行回顾性分析.其中男19例,女2例,年龄19~45岁,平均(31±7)岁.腕骨脱位位于左侧14例,右侧7例.结果 月骨脱位8例;月骨周围型脱位13例,其中,单纯月骨周围型脱位3例,经舟状骨月骨周围脱位4例,经舟状骨、三角骨月骨周围脱位1例,经三角骨月骨周围脱位3例,经桡骨茎突月骨周围性脱位2例.在伴有其他腕骨骨折的病例中,桡骨茎突及舟骨骨折于X线平片均得到确诊,而3例合并三角骨骨折的病例在X线平片上或不能显示骨折,或显示骨折片但不能确定具体部位.运用螺旋CT薄层扫描及重组后均做出了正确诊断.结论 X线平片对于腕骨脱位大多可以做出正确诊断,但当合并腕骨骨折,特别是细微骨折时,漏诊率较高,多层螺旋CT的MPR、VR技术可全面、准确地显示腕骨脱位及合并骨折情况,具有较高的临床应用价值.     

Advanced imaging of glenohumeral instability: the role of MRI and MDCT in providing what clinicians need to know

The inherently unstable anatomy of glenohumeral (GH) joint predisposes it to shoulder dislocation. Shoulder dislocation can occur either due to acute trauma or due to chronic microtraumas in the setting of underlying morphological abnormality. A plain radiograph is the initial imaging modality for diagnosis and management of shoulder dislocation and its associated osseous abnormalities such as Hill-Sachs deformity or osseous Bankart lesion. However, advanced imaging techniques such as multidetector CT (MDCT) with three-dimensional (3D) volume rendering and MRI can be helpful in further characterization of osseous abnormalities and detection of associated soft tissue injuries, respectively. These additional findings may be useful for optimal surgical repair for GH joint stabilization. In this pictorial essay, we present the clinically relevant osseous and soft tissue pathologies in various types of shoulder dislocation, with emphasis on pathologies that can be demonstrated using advanced imaging examinations. Discussed pathologies include glenoid fractures, labral tears, Bankart lesion, Hill-Sachs defect, Perthes lesion, anterior labral posterior sleeve avulsion (ALPSA), glenolabral articular disruption (GLAD), humeral avulsion of the glenohumeral ligament (HAGL), Kim lesion, and other associated soft tissue and nerve injuries.     

MRI of shoulder instability

The most unstable joint in the body, the glenohumeral joint is subject to many insults including microinstability, subluxation and dislocation. During the last two decades, MRI has allowed for direct visualization of many of the lesions related to instability, aiding in diagnosis as well as therapeutic planning and follow-up. This article reviews the use of MRI for shoulder instability and describes the different types of lesions associated with this disorder. Topics include technical considerations, the use of MR arthrography, normal anatomy and variants, labral and glenohumeral ligament pathology, and osseous lesions related to instability.     

Computed tomography and magnetic resonance imaging evaluation of patellofemoral instability

Malalignment and tracking abnormalities of the patellofemoral joint are common causes of anterior knee pain,which are often difficult to evaluate clinically. Conventional radiography, as well as the cross-sectional imaging modalities of computed tomography (CT) and magnetic resonance imaging (MRI) are useful tools for both detecting and quantifying these abnormalities. Acute transient dislocation of the patella, on the other hand, is a relatively uncommon injury accounting for only 2% to 3% of all acute injuries of the knee, and can also be a difficult diagnosis to establish on the basis of history and physical findings alone. MRI is a sensitive, noninvasive method for detecting prior acute transient dislocation of the patella. This article begins by describing the role of CT and MRI as it pertains to the detection of abnormal patellofemoral tracking. Both static and dynamic techniques are described along with the standard criteria used to establish and quantify patellofemoral malalignment abnormalities. Next, the constellation of MRI findings most commonly encountered after acute transient dislocation of the patella are described. These findings include a typical bone bruise pattern involving the anterolateral aspect of the lateral femoral condyle and inferomedial patella, hemarthrosis, and injury to the medial soft-tissue restraints (especially the medial patellofemoral ligament). After transient dislocation of the patella, patients with significant osteochondral injury or disruption of the medial soft-tissue restraints may benefit from surgical repair. The role of MRI in preoperative planning is discussed as it relates to the detection of osteochondral injuries as well as injury to the medial soft-tissue restraints.     

Ligamentous injuries of the wrist in athletes.

The athlete's wrist is particularly prone to injury. Although many wrist injuries are dismissed as sprains or strains, a number of these injuries involve significant ligamentous damage that can lead to chronic carpal instability. A complete knowledge of the carpal ligamentous anatomy and classification of wrist instability patterns is necessary for the adequate diagnosis and treatment of these injuries.