Anteromedial impingement of the ankle: using MR arthrography to assess the anteromedial recess

Direct MR arthrography without image guidance: a practical guide, joint-by-joint

Direct MR arthrography (dMRA) is a fundamental technique in diagnosing pathology in major peripheral joints, allowing for precise evaluation of intra-articular structures. Although injection guidance is typically performed using imaging techniques such as ultrasound or fluoroscopy, puncture via anatomical landmarks may be useful in certain circumstances where it has been proven to be a safe and effective procedure. This paper describes the indications and injection technique of dMRA, joint by joint, focusing on the different technical details, from the most common locations, like the shoulder or hip, to those with more restricted clinical indications, such as the wrist, knee, elbow, or ankle. The most relevant anatomical landmarks are detailed for each joint, aiding in the intra-articular introduction of diluted contrast, highlighting the most accessible trajectories and structures to avoid when inserting the needle. Additionally, tips are provided to facilitate proper joint distension. With all this information, this paper aims to serve as a suitable reference guide for performing dMRA without image guidance if needed.

SSR white paper: guidelines for utilization and performance of direct MR arthrography

OBJECTIVE

Direct magnetic resonance arthrography (dMRA) is often considered the most accurate imaging modality for the evaluation of intra-articular structures, but utilization and performance vary widely without consensus. The purpose of this white paper is to develop consensus recommendations on behalf of the Society of Skeletal Radiology (SSR) based on published literature and expert opinion.

MATERIALS AND METHODS

The Standards and Guidelines Committee of the SSR identified guidelines for utilization and performance of dMRA as an important topic for study and invited all SSR members with expertise and interest to volunteer for the white paper panel. This panel was tasked with determining an outline, reviewing the relevant literature, preparing a written document summarizing the issues and controversies, and providing recommendations.

RESULTS

Twelve SSR members with expertise in dMRA formed the ad hoc white paper authorship committee. The published literature on dMRA was reviewed and summarized, focusing on clinical indications, technical considerations, safety, imaging protocols, complications, controversies, and gaps in knowledge. Recommendations for the utilization and performance of dMRA in the shoulder, elbow, wrist, hip, knee, and ankle/foot regions were developed in group consensus.

CONCLUSION

Although direct MR arthrography has been previously used for a wide variety of clinical indications, the authorship panel recommends more selective application of this minimally invasive procedure. At present, direct MR arthrography remains an important procedure in the armamentarium of the musculoskeletal radiologist and is especially valuable when conventional MRI is indeterminant or results are discrepant with clinical evaluation.

Does Direct MRI Tenography Improve the Diagnostic Performance of Low-Field MRI to Identify Artificially Created Soft-Tissue Lesions within the Equine Cadaveric Digital Flexor Tendon Sheath?

Tenosynovitis of the digital flexor tendon sheath (DFTS) is diagnosed using ultrasonography and contrast tenography. Nevertheless, making a precise preoperative diagnosis is challenging. This study aimed to determine and compare the sensitivity and specificity of low-field MRI and MRI tenography (MRIt) to detect artificially created soft-tissue lesions in the DFTS. In 21 DFTSs, 118 lesions were made tenoscopically in the superficial digital flexor tendon (SDFT), deep digital flexor tendon (DDFT), manica flexoria (MF) and proximal scutum. MRI and MRI, following intrathecal gadolinium administration (MRIt), were performed. The sensitivity and specificity of MRI and MRIt were calculated and compared. Proximal scutum lesions were less frequently identified by MRI (Sensitivity 38%, specificity 96%) compared to MRIt (Sensitivity: 50%, p = 0.80; specificity: 96%, p = 1). This was similar for SDFT lesions (Sensitivity: 39% versus 54%, p = 0.72; specificity: 93% versus 96%, p = 1). MRI detected DDFT lesions (sensitivity 34%; specificity 100%) better than MRIt (sensitivity 32%, p = 0.77; specificity 98%, p = 1). This was similar for MF lesions (MRI sensitivity 61%; specificity 100% vs. MRIt sensitivity 50%, p = 0.68; specificity 96%, p = 1). Lesion size was significantly associated with MRI or MRIt diagnosis (p = 0.001). The intrathecal administration of gadolinium did not significantly improve the ability of low-field MRI to diagnose artificial DFTS tendon lesions. Small lesion length was a significant discriminating factor for lesion detection. MRI and MRIt specificity were high, thus being helpful in diagnosing an intact structure.

Arthroscopic Treatment of Anterior Ankle Impingement

Arthroscopic reduction of tibiotalar osteophytes results in good to excellent results in the vast majority of patients. Pain is primarily due to synovial hypertrophy and anterior tibiotalar entrapment associated with the osteophytes. Osteophytes may be due to repetitive trauma such as sports, or associated with subtle or overt ankle instability. A minimally invasive approach results in rapid recovery and less risk than open interventions. In cases where anterior osteophytes have coexisting ankle instability and in many cases ancillary procedures such as ankle stabilization are performed.

Impingement syndromes of the ankle and hindfoot

Ankle impingement refers to a chronic painful mechanical limitation of ankle motion caused by soft-tissue or osseous abnormality affecting the tibiotalar joint or extraarticular soft tissues. Impingement can be associated with a prior single traumatic event or repetitive microtrauma, often in an adolescent with anatomical predisposition. Impingement syndromes at the tibiotalar joint can be subdivided into anterior, anterolateral, anteromedial, posterior or posteromedial. Extraarticular impingement can consist of talocalcaneal or subfibular impingement. Impingement syndromes are just one possible etiology of persistent ankle pain, and although the diagnosis is often made or suspected clinically, the radiologist might be the first person to raise the possibility of the diagnosis or be called upon to provide support for the clinically suspected diagnosis. In this article I review the etiology, imaging findings and current treatment associated with these conditions.

ACR Appropriateness Criteria® Chronic Ankle Pain

Chronic ankle pain is a common clinical problem whose cause is often elucidated by imaging. The ACR Appropriateness Criteria for chronic ankle pain define best practices of image ordering. Clinical scenarios are followed by the imaging choices and their appropriateness. The information is in ordered tables with an accompanying narrative explanation to guide physicians to order the right test. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Imaging of Ankle Impingement Syndromes

Ankle impingement syndromes are a commonly encountered clinical entity seen in athletes, secondary to repetitive forceful microtrauma. Symptoms are related to impingement of osseous or soft tissue abnormalities in the ankle joint, in particular the tibiotalar joint, which may result in painful limitation of ankle movements. Imaging modalities, such as radiographs and magnetic resonance imaging, are very useful in diagnosing osseous and soft tissue abnormalities seen in different types of ankle impingement syndromes. This article reviews the classification of ankle impingement syndromes, their etiology, and clinical and radiological findings.

Soft Tissue Impingement of the Ankle: Pathophysiology, Evaluation, and Arthroscopic Treatment

Soft tissue impingement (STI) syndrome is one of 3 causes of a larger all-encompassing joint impingement pathologic condition, which also includes bone and neuropathic entrapment. Altered joint biomechanics and friction of joint tissues combine to cause chronic pain and often functional instability. Although the most common form of STI to the ankle is anterolateral in location, posterior and anteromedial impingement is also discussed in this article. Furthermore, a discussion of biomechanical deficiencies and how they may effect location and cause of STI of the ankle is explored along with pathophysiology, clinical and diagnostic evaluation, current treatments, and long-term outcomes.

Imaging of Common Arthroscopic Pathology of the Ankle

Arthroscopy of the ankle is used in the treatment and diagnosis of a spectrum of intra-articular pathology including soft tissue and osseous impingement, osteochondral lesions, arthrofibrosis, and synovitis. To help identify the correct pathology, imaging techniques are often used to aid the surgeon in diagnosing pathology and determining best treatment options. This article discusses the use of imaging in various ankle pathologies.

Sonographically guided therapeutic injections in the meniscoid lesion in patients with anteromedial ankle impingement syndrome

We describe a sonographically guided technique to perform therapeutic injections for anteromedial ankle impingement syndrome. Scans are carried out using a high-frequency small footprint linear array transducer, positioned along the anteromedial aspect of the tibiotalar joint. A 25 gauge needle is advanced under direct sonographic guidance into the "meniscoid lesion" (area of scarring), and a standardized therapeutic mixture is injected extra-articularly. Image-guided injections have a positive influence on clinical decision making by improving patient management, increasing the accuracy of diagnosis, and decreasing patient pain. Sonography allows confirmation of correct injection placement, resulting in increased accuracy and more successful patient outcomes.

LEVELS OF EVIDENCE

Therapeutic, Level V, Expert Opinion.

US in ankle impingement syndrome

Ankle impingement is a common condition occurring secondary to sprain or repeated microtrauma. Clinical symptoms are chronic pain located in the affected region and limited range of ankle motion. There are three types of ankle impingement syndrome: anterior impingement, which can be subdivided into anterolateral, anteromedial and purely anterior impingement; posterior impingement, which can be subdivided into posterior and posteromedial impingement; and calcaneal peroneal impingement which is secondary to planovalgus foot deformity. This paper evaluates physiological and clinical elements of these three types of ankle impingement syndrome as well as the role of ultrasound (US) imaging and US-guided treatment.

Ankle impingement: a review of multimodality imaging approach

Ankle impingement is defined as entrapment of an anatomic structure that leads to pain and decreased range of motion of the ankle and can be classified as either soft tissue or osseous (Bassett et al. in J Bone Joint Surg Am 72:55-59, 1990). The impingement syndromes of the ankle are a group of painful disorders that limit full range of movement. Symptoms are due to compression of soft-tissues or osseous structures during particular movements (Ogilvie-Harris et al. in Arthroscopy 13:564-574, 1997). Osseous impingement can result from spur formation along the anterior margin of the distal tibia and talus or as a result of a prominent posterolateral talar process, the os trigonum. Soft-tissue impingement usually results from scarring and fibrosis associated with synovial, capsular, or ligamentous injury. Soft-tissue impingement most often occurs in the anterolateral gutter, the medial ankle, or in the region of the syndesmosis (Van den Bekerom and Raven in Knee Surg Sports Traumatol Arthrosc 15:465-471, 2007). The main impingement syndromes are anterolateral, anterior, anteromedial, posterior, and posteromedial impingement. These conditions arise from initial ankle injuries, which, in the subacute or chronic situation, lead to development of abnormal osseous and soft-tissue thickening within the ankle joint. The relative contributions of the osseous and soft-tissue abnormalities are variable, but whatever component is dominant there is physical impingement and painful limitation of ankle movement. Conventional radiography is usually the first imaging technique performer and allows assessment of any potential bone abnormality, particularly in anterior and posterior impingement. Computed tomography (CT) and isotope bone scanning have been largely superseded by magnetic resonance (MR) imaging. MR imaging can demonstrate osseous and soft-tissue edema in anterior or posterior impingement. MR imaging is the most useful imaging modality in evaluating suspected soft-tissue impingement or in excluding other ankle pathology such as an osteochondral lesion of the talus. MR imaging can reveal evidence of previous ligamentous injury and also can demonstrate thickened synovium, fibrosis, or adjacent reactive soft-tissue edema. Studies of conventional MR imaging have produced conflicting sensitivities and specificities in assessment of anterolateral impingement. CT and MR arthrographic techniques allow the most accurate assessment of the capsular recesses, albeit with important limitations in diagnosis of clinical impingement syndromes. In the majority of cases, ankle impingement is treated with conservative measures, with surgical debridement via arthroscopy or an open procedure reserved for patients who have refractory symptoms. In this article, we describe the clinical and potential imaging features, for the four main impingement syndromes of the ankle: anterolateral, anterior, anteromedial, posterior, and posteromedial impingement.

Diagnostic imaging of ankle impingement syndromes in athletes

The chronic ankle pain is a very frequent clinical problem, which is often characterized by a painful mechanical limitation of full-range ankle movement. A large amount of causes are involved in its pathogenesis, but the most common forms are secondary to an osseous or soft tissue abnormality. Especially for professional athletes, impingement lesions are the most important causes of chronic pain; however, this symptomatology can also affect ordinary people, mostly in those who work in environments that cause severe mechanical stress on the joints. This group of pathologies is characterized by a joint conflict secondary to an abnormal contact among bone surfaces or between bones and soft tissues. Diagnosis is mainly clinic and secondly supported by imaging in order to localize the critical area of impingement and determine the organic cause responsible for the joint conflict. Treatments for different forms of impingement are similar. Usually, the first step is a conservative approach (rest, physiotherapy, ankle bracing, shoe modification and local injection of corticosteroids), and only in case of unsuccessful response, the second step is the operative treatment with open and arthroscopic techniques. The aim of the study is to describe different MR imaging patterns, comparing our data with those reported in the literature, in order to identify the best accurate diagnostic protocol.

Tibialis posterior tendon and deltoid and spring ligament injuries in the elite athlete

The tibialis posterior tendon and the spring and deltoid ligament complexes combine to provide dynamic and passive stabilization on the medial side of the ankle and hindfoot. Some of the injuries will involve acute injury to previous healthy structures, but many will develop insidiously. The clinician must be aware of new treatment strategies and the level of accompanying scientific evidence regarding injuries sustained by athletes in these areas, while acknowledging that more traditional management applied to nonathletic patients is still likely to be appropriate in the setting of treatment for elite athletes.

Posterior ankle impingement

Posterior ankle impingement is a common cause of chronic ankle pain and results from compression of bony or soft tissue structures during ankle plantar flexion. Bony impingement is most commonly related to an os trigonum or prominent trigonal process. Posteromedial soft tissue impingement generally arises from an inversion injury, with compression of the posterior tibiotalar ligament between the medial malleolus and talus. Posterolateral soft tissue impingement is caused by an accessory ligament, the posterior intermalleolar ligament, which spans the posterior ankle between the posterior tibiofibular and posterior talofibular ligaments. Finally, anomalous muscles have also been described as a cause of posterior impingement.

Anteromedial impingement in the ankle joint: outcomes following arthroscopy

BACKGROUND

Arthroscopic debridement is a well-accepted method of removing osseous and/or soft tissue impingement from the ankle joint. To the best of the authors' knowledge, this is the first case series reporting the outcomes following arthroscopic resection of anteromedial impingement.

PURPOSE

The authors report the results at a minimum 2-year follow-up of 41 patients who underwent arthroscopic resection for anteromedial impingement.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Arthroscopic surgery for anteromedial impingement was performed on 43 patients under the care of the senior surgeon between January 2005 and July 2007; 41 patients were included in the present study. All patients were assessed preoperatively and postoperatively using the American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot and Short Form 36 (SF-36v2) outcome scores. The mean patient age at the time of surgery was 31.12 years (range, 13-57 years). The mean follow-up time was 34.41 months (range, 24-52 months). Thirty-four patients (83%) were competing at some level of athletic sport.

RESULTS

Thirty-eight patients (93%) were satisfied with the procedure. The AOFAS scores improved from 62.83 points preoperatively to 91.17 points postoperatively (range, 61-100 points) (P < .001). The SF-36v2 scores improved from 61.54 points preoperatively to 92.21 points postoperatively (range, 58-100 points) (P = .002). All but 1 patient returned to their prior level of sporting activity. Three patients (7%) reported a complication.

CONCLUSION

Arthroscopic resection for anteromedial impingement provides excellent functional outcomes, thereby allowing the athlete an expedited return to sport at previous levels of competition.

MR imaging of deltoid ligament pathologic findings and associated impingement syndromes

Injuries of the deltoid ligament of the ankle are increasingly recognized with the widespread use of magnetic resonance (MR) imaging. The use of higher magnetic field strengths requires familiarity with the anatomic substructure of the deltoid ligament to better localize and characterize pathologic findings. Specifically, improved image resolution allows components of the superficial (tibiocalcaneal, tibionavicular, posterior superficial tibiotalar, and tibiospring ligaments) and deep (anterior tibiotalar and posterior deep tibiotalar ligaments) portions of the ligament to be evaluated separately. Awareness of the deltoid ligament substructure and associated injury patterns can guide the radiologist in defining underlying mechanical derangement, such as that seen in various impingement disorders. In this review article, the MR imaging technique for the deltoid ligament is summarized, and the normal and abnormal MR imaging appearances of various components of the deltoid ligament and associated impingement syndromes are presented.

Imaging of impingement lesions in the ankle

Ankle impingement and instability are well-recognized complications of ankle sprain. Ankle impingement is an important cause of chronic ankle pain in active populations, particularly in the professional athlete. Depending on anatomical location and the structures involved, impingement syndromes are classified into anterolateral, anterior, posterior, posteromedial, and anteromedial types. Clinically, impingement syndromes are characterized by painful limitation of full-ankle movement. Ankle impingement results from repetitive subclinical trauma due to overuse injuries, which, in the subacute or chronic situation, lead to abnormal osseous and soft-tissue thickening within the ankle joint. Various imaging techniques can be used in the diagnosis of ankle impingement. Usually, radiography is the initial imaging technique performed to rule out bony trauma and identify potential anatomical bony abnormalities. Use of computed tomography and isotope bone scanning is largely superseded by magnetic resonance imaging, although with variable sensitivity and specificity. Arthrographic techniques, using computed tomography or magnetic resonance, are useful for exquisite demonstration of capsular recesses and synovial abnormalities. Imaging-guided injection techniques can be used in the management of impingement for pain ablation and to aid clinical diagnosis, especially in hind foot pain.

Magnetic resonance arthrography

Magnetic resonance arthrography is widely used throughout the world for joint imaging. It extends the capabilities of conventional MR imaging because contrast solution distends the joint capsule, outlines intraarticular structures, and extends into soft tissue tears and defects. MR arthrography exploits the natural advantages gained from a joint effusion and can be performed on any joint.

3T magnetic resonance imaging of ankle and hindfoot tendon pathology

Ankle tendon pathology is relatively common in the active adult population. Magnetic resonance imaging is often the preferred advanced imaging option for the evaluation of tendon pathology of the hindfoot and ankle. The almost linear increase in signal-to-noise ratio provided by higher field strength imaging allows for improved image resolution and decreased scan times. Newer systems with faster gradients allow for optimal fast spin-echo imaging with lower echo spacing for longer echo train lengths and minimal image blurring. The ability to comfortably scan the ankle within the magnet isocenter using high-field strength-compatible extremity coils further maximizes the image resolution. It is imperative for the radiologist to be aware of necessary protocol adjustments and potential imaging artifacts unique to high-field strength imaging of the ankle. Our review outlines high-field strength magnetic resonance imaging technique and artifacts and also details the specifics of our own methods of ankle imaging.

MR arthrography of the ankle: indications and technique

MR arthrography has become an important tool for the assessment of a variety of ankle disorders. MR arthrography permits more sensitive imaging of suspected intra-articular pathology in cases in which conventional MR imaging is either insufficient or inadequate for diagnosis or treatment planning. The main indications for MR arthrography are the evaluation of ligamentous injuries, impingement syndromes, cartilage lesions, osteochondral lesions of the talus, loose bodies, and several synovial joint disorders. Indirect MR arthrography can be a useful adjunct to conventional MR imaging and may be preferable to direct MR arthrography in those cases in which an invasive procedure is contraindicated or image guidance is not available.

Ankle impingement syndromes

Acute or repetitive trauma to the ankle can result in painful restriction of movement caused by impingement of soft tissue and osseous structures. Ankle impingement syndromes are classified according to their anatomic relationship to the tibiotalar joint. This article reviews the relevant anatomy, etiology, and clinical features of ankle impingement syndromes, and demonstrates the potential imaging findings and discusses management of each for these conditions.

Imaging evaluation of chronic ankle and hindfoot pain in athletes

Acute ankle and hindfoot injuries are common in athletes and typically are treated conservatively. Persistent pain that has not responded to appropriate conservative treatment and prevents the patient from returning to play is more problematic for the athlete and the treating sports clinician. Making a specific clinical and imaging diagnosis in these patients can be quite challenging. This article discusses the imaging evaluation of chronic ankle and hindfoot pain related to osseous and soft-tissue injuries in athletes. MR imaging is the preferred imaging modality in most of the presented cases.

Impingement syndromes of the ankle

Ankle impingement syndromes are categorised according to their anatomical site around the tibiotalar joint. Anterolateral, anterior and posterior ankle impingement has been extensively described in the orthopaedic and radiology literature with more recent studies describing posteromedial and anteromedial impingement. This article aims to demonstrate the potential spectrum of imaging findings for each ankle impingement syndrome as well as the relative contributions of ultrasound and MR imaging for diagnosis and image-guided treatment.

Ankle instability and impingement

Ankle instability and ankle impingement are well-known complications of an ankle sprain. Both diagnosis are made primarily by history and physical examination. Ankle instability may resolve with physical therapy, but can require surgical reconstruction. Anatomic reconstruction is preferred whenever possible. Ankle impingement usually requires surgical treatment. Anterior soft tissue impingement and mild bony impingement confined to the tibia can be treated arthroscopically, whereas more severe anterior bony impingement and any form of posterior impingement require an open procedure. Ankle ligament reconstruction and surgical treatment of ankle impingement are reliably effective procedures.

[Impingement and kinesiology]

During physical activity, especially in sport, repeated and/or exaggerated movements may lead to different impingements. Rupture, luxation, and tendon insertion injuries are seen after mobilization in the acute phase, but the goal of this paper is to analyze chronic impingements. It is possible to see the consequences of these impingements in all the musculoskeletal structures but, in relation to movement, three groups can be described. In the first, there is chronic compression and percussion between two structures; in the second there is entrapment and friction, and in the third, there is distraction. These impingements are frequent and are seen in all people, but particular movements during sport can increase their frequency.

Magnetic resonance arthrography

For decades, fluoroscopic arthrography was the only method available to image a joint with contrast enhancement. Advances in CT led to the natural development of CT arthrography. Development of MRI and its capability for multiplanar imaging led to direct magnetic resonance arthrography (MRA). This technique has been performed since 1987 and has surpassed CT arthrography in popularity in the United States. Indirect MRA developed subsequently to offer a less invasive alternative. This article presents an overview of direct MRA and addresses joint-specific issues regarding direct MRA. An overview of indirect MRA also is provided.

MR-imaging of anterior tibiotalar impingement syndrome: Agreement, sensitivity and specificity of MR-imaging and indirect MR-arthrography

OBJECTIVE

To clarify the role of MR-imaging in the diagnosis of anterior ankle impingement syndromes.

MATERIALS AND METHODS

We prospectively examined 51 consecutive patients with chronic ankle pain by MR-imaging. Arthroscopy was performed in 29 patients who previously underwent non-enhanced MR-imaging; in 11 patients, indirect MR-arthrography additionally was performed. MR-examinations were correlated with clinical findings; MR and arthroscopy scores were statistically compared, agreement was measured.

RESULTS

Arthroscopy demonstrated granulation tissue in the lateral gutter (38%) and anterior recess (31%), lesions of the anterior tibiofibular (31%) and the anterior talofibular ligament (21%) as well as intraarticular bodies (10%). Stenosing tenosynovitis and a ganglionic cyst were revealed as extraarticular causes for chronic ankle pain by MR-examination (17%). Agreement of MR-imaging and arthroscopy was fair for the anterior talofibular ligament and the anterior joint cavity (kappa 0.40). Major discrepancy was found for non-enhanced MR scans (kappa 0.49) when compared with indirect MR-arthrography (kappa 0.03) in the anterior cavity. The sensitivity for lesions of the anterior talofibular and calcaneofibular ligament and the anterior cavity (0.91-0.87) detected by MR-imaging was superior in comparison to lesions of the anterior tibiofibular ligament and anteromedial cavity (0.50-0.24).

CONCLUSION

MR-imaging provides additional information about the mechanics of chronic ankle impingement rather than an accurate diagnosis of this clinical entity. The method is helpful in differentiating extra- from intra-articular causes of ankle impingement. Indirect MR-arthrography has little or no additional value in patients with ankle impingement syndrome.

An overview of MR arthrography with emphasis on the current technique and applicational hints and tips

Magnetic resonance (MR) arthrography has been investigated in every major peripheral joint of the body, and has been proven to be effective in determining the integrity of intraarticular ligamentous and fibrocartilaginous structures and in the detection or assessment of osteochondral lesions and loose bodies in selected cases. Several methods could be used to create arthrogram effect during MR imaging, however, direct MR arthrography using diluted gadolinium as the contrast agent is the most commonly used technique and is the most reliable of all. MR arthrography is useful for demonstrating labrocapsular-ligamentous abnormalities and distinguishing partial thickness rotator cuff tears from focal full thickness tears in the shoulder, identifying or excluding recurrent tears following meniscal operations in the knee, demonstrating perforations of the triangular fibrocartilage complex (TFCC) and ligaments in the wrist, showing labral tears in the hip, diagnosing ligament tears in the ankle and identifying osteochondral lesions or loose bodies in any of the aforementioned joints. In this article, an overview of techniques of MR arthrography is provided with emphasis on direct MR arthrography using diluted gadolinium as the contrast agent. The current applications of the technique in major peripheral joints are reviewed, with emphasis given to the shoulder joint where the role of this technique has become well established.

Comparison of plain MRI and MR arthrography in the evaluation of lateral ligamentous injury of the ankle joint

BACKGROUND

The purpose of this study was to determine the efficacy of plain magnetic resonance imaging (MRI) and magnetic resonance (MR) arthrography for detecting collateral ligamentous injury of the ankle joint.

METHODS

Fifty patients (October 2001 to November 2003) suffering from ankle disability who underwent plain MRI and MR arthrographic studies were enrolled in this study. The diagnostic criteria for ligament disruption on plain MRI included nonvisualization, disruption, waviness of the ligament, or coexistent avulsion fracture. The MR arthrographic findings of ligament disruption were based on leakage of gadolinium contrast medium anterior to the anterior talofibular (ATaF) ligament following ATaF ligament disruption, and the contrast medium filling into the common peroneal tendon sheath after calcaneofibular (CF) ligament disruption. The 2 modalities were interpreted respectively and blindly.

RESULTS

Seventeen patients received surgical intervention. There were 14 patients who had a torn ATaF ligament and 6 patients who suffered from CF ligament disruption proved by surgery. Limited detection of preoperative plain MRI survey, which showed 12 patients had torn ATaF and 2 patients had torn CF ligament, was noted. However, most patients with ligamentous injury were correctly diagnosed by MR arthrography preoperatively (only 1 case of CF injury was missed). The plain MRI alone had a higher incidence of false negative and false positive detection. MR arthrography was also valuable for evaluating the coexisting intra-articular pathologies of the ankle joint.

CONCLUSION

For evaluating ankle disability, using plain MRI alone is not adequate for correctly detecting lateral collateral ligamentous injury of the ankle joint. MR arthrography improves the sensitivity and the accuracy for ATaF and CF ligament injuries. It also helps in assessing coexisting pathologic lesions of ankle joints, especially impingement syndromes and osteochondral lesions, and provides more information for therapeutic decision making.

Ankle MR Arthrography: How, Why, When

MR arthrography has become an important tool for the assessment of a variety of ankle disorders. MR arthrography may facilitate the evaluation of patients with suspected intra-articular pathology in whom conventional MR imaging is not sufficient for an adequate diagnosis and be useful for therapy planning. MR arthrography is valuable in the evaluation of ligamentous injuries, impingement syndromes, cartilage lesions, osteochondral lesions of the talus, loose bodies, and several synovial joint disorders. Indirect MR arthrography is a useful adjunct to conventional MR imaging and may be preferable to direct MR arthrography in cases in which an invasive procedure is contraindicated or when fluoroscopy is not available.

Direct magnetic resonance arthrography

Magnetic resonance (MR) arthrography has gained increasing popularity as a diagnostic tool in the assessment of intra-articular derangements. Its role has been studied extensively in the shoulder, but it also has been explored in the hip, elbow, knee, wrist and ankle. This article reviews the current role of direct MR arthrography in several major joints, with consideration of pertinent anatomy, techniques and applications.

Diagnostic and therapeutic injections of the foot and ankle

Directed injections of the foot and ankle performed under fluoroscopic guidance have both considerable diagnostic value and the potential for targeted therapy by accurately delivering corticosteroid and/or anesthetic to the source of pain. Both large and small joints in the foot and ankle are readily accessed, offering precise information to the foot and ankle surgeon who may be contemplating arthrodesis or other intervention. In addition to its role in pain management, ankle arthrography may be performed in conjunction with MRI or CT, with improved evaluation of articular cartilage and capsular abnormalities.

Magnetic resonance imaging of sports injuries of the ankle

Basic sports-related injuries of the ankle include ligament tear, tendon degeneration and tear, bone bruise, fracture, impingement, osteochondral defect, and plantar fasciitis. This article discusses the magnetic resonance imaging appearance of these injuries.