Imaging Manifestations of Ankle Impingement Syndromes

Validation of anterior ankle soft tissue dynamics and shear modulus for anterior ankle impingement syndrome after ankle fracture surgery

Anterior ankle impingement syndrome (AAIS) has been reported to account for a high percentage of complications following ankle fracture surgery. The soft tissue etiology of AAIS is thought to be thickening and inflammation of the anterior ankle soft tissues intervening anteriorly at the tibiotalar joint, causing pain and functional limitation during dorsiflexion. However, the effects of anterior ankle soft tissue dynamics and stiffness on AAIS have yet to be clarified. This study aimed to determine the relationship between AAIS and the anterior ankle soft tissue thickness change ratio and shear modulus using ultrasonography (US). The participants were 20 patients with ankle joint fractures (AO classification A, B) who had undergone open reduction and internal fixation and 20 healthy adults. The evaluation periods were 3 months and 6 months postoperatively. US was used to delineate the tibialis anterior tendon, extensor hallucis longus tendon, and the extensor digitorum longus tendon over the talus and tibia on a long-axis image. Anterior ankle soft tissue thickness was measured as the shortest distance from the most convex part of the talus to the tendon directly above it. The Anterior ankle soft tissue thickness change ratio was determined by dividing the value at 0° dorsiflexion by the value at 10° plantarflexion. The same images as for the anterior soft tissue thickness measurement were drawn for the shear modulus measurement, and the average shear modulus (kPa) was calculated using shear-wave elastography. There was no significant difference in the thickness change ratio between the postoperative and healthy groups. Compared with the healthy group, the shear modulus was significantly higher at 3 and 6 months in the postoperative group (p < 0.01). The shear elastic modulus at 6-month postoperative group was significantly lower than at 3-month postoperative group (p < 0.01). Anterior ankle joint soft tissue stiffness may increase after surgery for an ankle fracture.

EURO-MUSCULUS/USPRM Dynamic Ultrasound Protocols for Ankle/Foot

ABSTRACT

In this dynamic scanning protocol, ultrasound examination of the ankle is described using various maneuvers to assess different conditions. Real-time patient examination and scanning videos are used for better simulation of daily clinical practice. The protocol is prepared by several/international experts in the field of musculoskeletal ultrasound and within the umbrella of European Musculoskeletal Ultrasound Study Group in Physical and Rehabilitation Medicine/Ultrasound Study Group of the International Society of Physical and Rehabilitation Medicine.

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.

Update on Ankle and Foot Impingement

Ankle impingement syndromes are a well-recognized cause of chronic ankle symptoms in both the elite athletic and general population. They comprise several distinct clinical entities with associated radiologic findings. Originally described in the 1950s, advances in magnetic resonance imaging (MRI) and ultrasonography have allowed musculoskeletal (MSK) radiologists to further their understanding of these syndromes and the range of imaging-associated features. Many subtypes of ankle impingement syndromes have been described, and precise terminology is critical to carefully separate these conditions and thus guide treatment options. These are divided broadly into intra-articular and extra-articular types, as well as location around the ankle. Although MSK radiologists should be aware of these conditions, the diagnosis remains largely clinical, with plain film or MRI used to confirm the diagnosis or assess a surgical/treatment target. The ankle impingement syndromes are a heterogeneous group of conditions, and care must be taken not to overcall findings. The clinical context remains paramount. Treatment considerations are patient symptoms, examination, and imaging findings, in addition to the patient's desired level of physical activity.

The Role of Equinus in Flatfoot Deformity

Equinus plays an important role in flatfoot deformity. Proper evaluation and surgical management are critical to comprehensively treat and successfully resolved patients' symptoms. We have discussed the cause, evaluation, and some of the common surgical options. Each procedure has its inherent benefits and risks. It is imperative that the foot and ankle surgeon identify and include these procedures as part of the complete reconstructive surgery.

Clinical significance of the anteromedial talus osteophyte in anteromedial ankle impingement in chronic lateral ankle instability

PURPOSE

The aim of this study was to evaluate the relation between anteromedial ankle osteophytes (AMAO) and anteromedial ankle impingement (AMAI) in chronic lateral ankle instability (CLAI) through visualization and quantification.

METHODS

Forty-three patients with unilateral CLAI between September 2018 and March 2020 accepted arthroscopic repair of an anterior talofibular ligament (ATFL) and were split into two groups: AMAI (AMAI including intraoperative AMAO resection) and pure CLAI (with AMAO but without AMAI, no AMAO resection). The AMAO protrusion lengths in each direction were measured and compared after all of the ankles were reconstructed. All patients were assessed preoperatively and at 2-year follow-up with ankle dorsiflexion, the American Orthopedic Foot and Ankle Society (AOFAS) ankle-hindfoot score, and visual analog scale (VAS) score.

RESULTS

Intelligent analysis showed that a large extent of osteophytes was found at the dorsomedial surface of the talar neck in AMAI group. The upper and inner bound protrusion distances of AMAO in AMAI group were greater than in the pure CLAI group. There was no significant difference in anterior bound protrusion distance of AMAO between the two groups. Preoperatively, the ankle dorsiflexion of AMAI group (7.6 ± 1.4°) was considerably lower than that of pure CLAI group (22.4 ± 1.9°) (p < 0.001). When compared to the pure CLAI group, the AMAI group had a substantially worse AOFAS score (62.2 ± 6.7 vs 71.1 ± 9.1; p < 0.001) and VAS score (6.0 ± 1.0 vs 4.9 ± 0.8; p < 0.05). However, there was no significant difference in postoperative ankle dorsiflexion, AOFAS score, or VAS score between the two groups.

CONCLUSION

AMAO is formed mostly on the dorsomedial surface of the talar neck in CLAI with AMAI, and the upper and inner bound protrusion lengths of AMAO were shown to be significantly correlated with the existence of AMAI in CLAI.

LEVEL OF EVIDENCE IV

Imaging of Overuse Injuries of the Ankle and Foot in Sport and Work

Overuse injuries of the ankle and foot are common injuries both in sport and in a work-related context. After clinical assessment, imaging is key for early diagnosis. In this overview article, we focus on imaging techniques, protocols, and imaging findings of overuse injuries of the ankle and foot; we emphasize the important role of structured reporting; and we discuss clinical symptoms, epidemiology, and risk factors in sports and in a work-related context.

3-T MRI of the Ankle Tendons and Ligaments

Ankle sprain is the most common injury in athletic populations. Ligament and tendon pathologies of the ankle are common, ranging from traumatic injuries to degeneration leading to chronic pain and acquired foot deformities. MRI is the imaging modality of choice to evaluate tendon and ligament pathology of the ankle, specifically derangements of tendons and ligaments. 3-T MRI offers improved imaging characteristics relative to 1.5-T MRI, allowing for better delineation of anatomic detail and pathology. This article provides a review of the anatomy and common pathologies of the ankle ligaments and tendons using high-resolution 3-T MRI.

Ankle Impingement: A Critical Analysis Review

Ankle impingement presents with painful and limited range of motion with dorsiflexion or plantar flexion, originating from pathological contact between bone and/or soft-tissue structures. Diagnosis is made primarily through clinical examination with adjunct radiographs and magnetic resonance imaging, with care taken to rule out a plethora of similarly presenting pathologies. Arthroscopic surgical approaches bring satisfactory short, mid, and long-term outcomes, with the current body of evidence dominated by Level-IV studies. Minimally invasive techniques offer improvements in time to return to play and complication rates relative to open approaches. Recent advances in the arthroscopic management of ankle impingement include long-term outcome studies, novel prognostic classification systems, and strategies for concomitant lesion management.

Anterior and Posterior Ankle Impingement Syndromes: Arthroscopic and Endoscopic Anatomy and Approaches to Treatment

Ankle impingement refers to a chronic painful mechanical limitation of ankle motion caused by soft tissue or osseous abnormality affecting the anterior or posterior tibiotalar joint. Impingement can be associated with a single traumatic event or repetitive microtrauma. These syndromes are a possible etiology of persistent ankle pain. An arthroscopic approach to this pathology, when indicated, is considered as ideal treatment with its high safety and low complication rate. We describe the clinical and potential imaging features, and the arthroscopic/endoscopic management strategies, for the 4 main impingement syndromes of the ankle: anterolateral, anterior, antero-medial, and posterior.

Combined anterior and posterior ankle impingement syndrome with nonunion of Cedell fracture in a 58-year-old female: a case report

BACKGROUND

Combined anterior and posterior ankle impingement has seldom been reported. Cedell fracture, fracture of posteromedial tubercle of talus, is an uncommon and easily missed injury which may elicit posteromedial ankle impingement. The injury mechanisms and management strategies of these two lesions have been reported individually. But the concurrent lesion of both of them has not been reported.

CASE PRESENTATION

We reported a 58-year-old female with combined anterior and posterior ankle impingement syndrome with nonunion of Cedell fracture in whom open osteophytes debridement, fracture internal fixation and posterior talotibial ligament reconstruction were performed. The AOFAS hindfoot score was 90 at 1 year follow-up. To our knowledge, this was the first reported case with anterior, posterior and posteromedial impingement which was treated operatively with an excellent short-term outcome.

CONCLUSIONS

To fully recognize this occult lesion and avoid missing is imperative for reducing the morbidities. We suggest CT and MRI as excellent imaging modalities that can help the timely diagnosis and appropriate treatment for this combined impingement with circumferential lesions.

Correlation between the accessory anterolateral talar facet, bone marrow edema, and tarsal coalitions

OBJECTIVE

The purposes of this study was to determine the prevalence of the accessory anterolateral talar facet (AALTF); to evaluate the relationship between AALTF, focal abutting bone marrow edema (FABME), and sinus tarsi edema; and to study the prevalence of tarsal coalitions in patients with the AALTF utilizing ankle MR images.

MATERIALS AND METHODS

5-T ankle MR images were reviewed for the presence of AALTF, FABME, sinus tarsi edema, tarsal coalition, and location and type of coalition (cartilaginous, fibrous, and osseous). Multivariate analysis was performed to examine the correlation between AALTF and the other variables.

RESULTS

Three hundred ninety-one consecutive patients were included (age range 5-86 years; mean age 45 years). An AALTF was present in 3.6% (14/391) of patients. The AALTF prevalence was 2% in women and 6.6% in men. There was a significantly association between AALTF and FABME (9/14, p < 0.05), sinus tarsi edema (13/14, p < 0.05), and tarsal coalition (4/14, p < 0.05).

CONCLUSION

AALTF is relatively often detected on MRI of the ankle and significantly associated with BME, sinus tarsi edema, and subtalar coalition. Patients with a tarsal coalition should be evaluated for the concurrent presence of an AALTF.

Implications of Classification of Os Trigonum: A Study Based on Computed Tomography Three-Dimensional Imaging

BACKGROUND The os trigonum is an accessory bone that is not fully fused with the talus during secondary ossification, and is one of the risk factors of posterior malleolus impact syndrome. The purpose of this study was to classify the os trigonum and to guide the diagnosis and treatment of related clinical diseases. MATERIAL AND METHODS Ankle computed tomography (CT) scans of 586 Chinese patients between October 2014 and October 2018 were reviewed. CT images of 1011 ankle joints were reconstructed to evaluate the classification of the os trigonum and the measurement of anatomical parameters. RESULTS The incidences of os trigonum in 3 groups were determined as type I (1.9%), type II (10.5%), and type III (14.7%). The macro-axis of type II (0.89±0.31) cm was significantly larger than with type I (0.65±0.24 cm) and type III (0.74±0.23 cm) (p<0.05).The minor axis of similar of type I (0.41±0.23 cm) was significantly shorter than that of type II (0.58±0.32 cm) and type III (0.55±0.16 cm) (p<0.05).The distance from os trigonum to calcaneal tubercle was significantly different than that of type I (1.33±0.52 cm), type II (1.67±0.55 cm), and type III (1.84±0.45 cm) (p<0.05). CONCLUSIONS This study showed that os trigonum has a high incidence. Type I was the least common, the volume of type II was larger, and type III was more common. The anatomical parameters of each type may improve treatment of related diseases and the further development of ankle arthroscopic surgery.