Ankle and Foot: Focus on Inflammatory Disease.

The ankle and foot have numerous bones and complex joints that can be affected by several types of inflammatory arthritis with different patterns and various radiologic signs, depending on the phase of the disease. Involvement of these joints is most frequently seen in peripheral spondyloarthritis and rheumatoid arthritis in adults and juvenile idiopathic arthritis in children. Although radiographs are a mainstay in the diagnostic process, ultrasonography and especially magnetic resonance imaging allow early diagnosis and are crucial diagnostic tools. Some diseases have typical features based on target populations (e.g., adults versus children, men versus women), but others may have overlapping imaging characteristics. We highlight key diagnostic features and describe appropriate investigations to guide clinicians toward the correct diagnosis and provide support during disease monitoring.

Imaging update on soft tissue sarcoma.

Soft tissue sarcomas (STS) are rare tumours presenting as soft tissue lumps. Ultrasound is often the primary modality for the initial assessment, with MRI the mainstay for lesion characterisation. PET/CT along with other emerging MRI sequences are used in certain situations as an adjunct and problem solving tool in STS staging and assessment of disease recurrence. Recent advances include the promise of whole body MRI, hybrid PET/MRI, diffusion weighted imaging, dynamic contrast enhanced MRI and advances in artificial intelligence. This article discusses current concepts in extremity STS imaging and highlights recent advances.

Imaging update in spondyloarthropathy.

Although our understanding of axial spondyloarthropathy (axSpA) has increased recently, there has not been a concurrent improvement in patient diagnosis with delays contributing to patient morbidity. Imaging findings of axSpA can be subtle and may be dismissed often due to lack of understanding by reporters and importantly clinicians who do not suspect the disease. Recognition of the importance of imaging has led to the inclusion of MRI as part of the diagnostic criteria for axSpA. With this in mind, a number of advancements have been made in an attempt to increase our diagnostic accuracy on imaging. This article will give an overview of these techniques as well as a recap of the imaging features of axSpA.

Phosphaturic mesenchymal tumors: radiological aspects and suggested imaging pathway.

Phosphaturic mesenchymal tumors (PMTs) are rare mesenchymal neoplasms of soft tissue or bone origin that can give rise to a challenge in diagnostic imaging. These tumors are frequently associated with tumor-induced osteomalacia, also called oncogenic osteomalacia, which is a rare paraneoplastic syndrome characterized by ectopic secretion of fibroblast growth factor 23, a hormone that regulates serum phosphate level. PMTs show polymorphic features on both radiological findings and histological examination, causing problems in diagnosis owing to their similarity with other mesenchymal tumors. Thus, this paper aims to describe radiological aspects of PMTs and suggest an imaging pathway for accurate diagnosis throughout the evidence from the literature review.

Non-neoplastic Soft Tissue Tumors and Tumor-like Lesions.

Clinicians are commonly faced with patients presenting with a solitary palpable soft tissue mass. Most soft tissue lesions are benign, and not every mass is due to a neoplastic process. Many pathologies can mimic a malignant tumor. Despite appropriate clinicoradiologic assessment, these lesions can be mistaken for a soft tissue sarcoma and can lead to multiple investigations or an intervention, inconveniencing patients and leading to an increased health care cost. With the relevant clinical history, clinical examination, and specific imaging characteristics, the diagnosis can be narrowed. We present a pictorial review of soft tissue sarcoma mimics with guidance on appropriate differential diagnoses.

Concurrent Joint Hypermobility Syndrome and Spondyloarthropathy: A New Spondyloarthropathy Subgroup With a Less Severe Disease Phenotype?

BACKGROUND: The coexistence of joint hypermobility syndrome (JHS) and spondyloarthropathy (SpA) presents a challenging clinical conundrum due to the contradictory clinical signs that may be present. Classic features such as restricted spinal movement or early morning back stiffness may not be present. Timely diagnosis and appropriate management of these patients are difficult as they tend to have lower scores on validated objective measures. METHODS: We performed a medical records review study to identify patients with both JHS and SpA who had presented to the Leicester Spondyloarthropathy clinic. Patients were diagnosed with axial SpA if they met the Assessment of SpondyloArthritis international Society classification criteria. Their imaging was reviewed by a consultant musculoskeletal radiologist. RESULTS: Four cases were identified from the patient database (female; average age, 37.5 years). All patients presented with lower back pain or sacroiliac joint pain but preserved spinal movement with a negative Schober's test. Two had a history of symptoms for more than 10 years. All had a Beighton score of greater than 6. Three of the patients were HLA positive, and 3 had a positive family history. All patients thus far have had their symptoms adequately controlled on nonsteroidal anti-inflammatory drugs and physiotherapy. CONCLUSIONS: The coexistence of JHS and SpA is rare but important to recognize. These patients are difficult to diagnose as they may present late because of preserved spinal movements. It is unclear whether the preserved flexibility masks the true extent of disease or whether clinically they represent a less severe disease phenotype.

Anterior Chest Wall in Axial Spondyloarthritis: Imaging, Interpretation, and Differential Diagnosis.

Anterior chest wall (ACW) inflammation is not an uncommon finding in patients with axial spondyloarthritis (ax-SpA) and reportedly occurs in 26% of these patients. Radiologists may only be familiar with spinal and peripheral joint imaging, possibly due to the inherent challenges of ACW imaging on some cross-sectional imaging modalities. Knowledge of relevant joint anatomy and the location of sites of inflammation allows the interpreting radiologist to better plan appropriate imaging tests and imaging planes. Accurate assessment of disease burden, sometimes in the absence of clinical findings, may alert the treating rheumatologist, allowing a better estimation of disease burden, increased accuracy of potential imaging scoring systems, and optimize assessment and response to treatment. This article reviews salient anatomy and various imaging modalities to optimize diagnosis, important differential diagnoses, and the interpretation of ACW imaging findings in ax-SpA.

Classification Terminology and Definitions in Reporting of MRI in Axial Spondyloarthritis.

Spondyloarthritis (SpA) is a group of chronic inflammatory conditions which severely impact quality of life. Several criteria have been developed in the past to aid the diagnosis of SpA based on symptoms and radiographic changes during the course of the disease. However, it takes several years before structural changes manifest on conventional radiographs, leading to a diagnostic delay of 6 to 10 years. The use of MRI and its incorporation into the Assessment of Spondyloarthritis (ASAS) criteria, has radically changed the diagnosis of SpA in the last decade by allowing visualisation of both active and chronic inflammatory changes and enabling clinicians to recognise SpA during it's early stage and initiate treatment. An understanding of the various terminology used in the divisions of disease presentations and their relevant imaging findings are key, along with the use of clear definitions of structural and inflammatory changes on MRI, in ensuring accurate diagnosis and classification of SpA.

Percutaneous Ultrasound-Guided TOPAZ Radiofrequency Coblation: A Novel Coaxial Technique for the Treatment of Recalcitrant Plantar Fasciitis-Our Experience.

Various therapeutic options are available for treatment of recalcitrant plantar fasciitis. Studies using TOPAZ coblation (ArthroCare, Sunnyvale, CA) have had good early results. The current coblation technique involves a surgical incision or breach of the highly specialized plantar fat pad, which can be associated with risks. We describe a novel technique of ultrasound-guided percutaneous coblation with a lateral heel approach. Advantages include precise targeting of the plantar fascia by direct dynamic visualization of the coblation tip, a true percutaneous approach with a needle skin puncture (<5 mm), and preservation of the plantar fat pad by using a lateral heel approach.

Development and Preliminary Validation of a Digital Overlay-based Learning Module for Semiquantitative Evaluation of Magnetic Resonance Imaging Lesions in Osteoarthritis of the Hip.

OBJECTIVE: To develop and validate a knowledge transfer (KT) module aimed at enhancing feasibility and reliability of semiquantitative assessment of bone marrow lesions (BML) and synovitis-effusion using the Hip Inflammation Magnetic Resonance Imaging Scoring System (HIMRISS). METHODS: Three radiologists naive to the HIMRISS method reviewed the manuscript describing the method and then scored MRI scans from 16 patients with hip OA obtained at baseline and 8 weeks after intraarticular injection of corticosteroid. Readers then reviewed a KT module comprising an instructional presentation and 8 reference DICOM (digital imaging and communications in medicine) cases scored by 3 readers with expertise in the HIMRISS method, and then used electronic overlay software to score scans from 23 patients with OA. The same format was followed with a second group of 3 readers naive to HIMRISS using a KT module revised to incorporate the overlay with a Web-based DICOM viewer to enhance feasibility. Interobserver reliability was assessed with the intraclass correlation coefficient (ICC). RESULTS: In both exercises, reliability for baseline scores was excellent for femoral BML, very good for acetabular BML, and good for synovitis-effusion (overall ICC = 0.91, 0.89, 0.62, respectively) even without prior calibration using the KT module. However, reliability for detecting change was substantially worse than for expert readers, especially for acetabular BML and synovitis-effusion (overall ICC = 0.59 vs 0.19, and 0.42 vs 0.25, respectively). Reliability improved for detection of change in these lesions, especially after reader calibration with the revised KT module. CONCLUSION: Development and validation of a systematic method for KT may enhance external validation of certain imaging instruments.

Recommendations of the ESSR Arthritis Subcommittee for the Use of Magnetic Resonance Imaging in Musculoskeletal Rheumatic Diseases.

This article presents the recommendations of the European Society of Musculoskeletal Radiology Arthritis Subcommittee regarding the standards of the use of MRI in the diagnosis of musculoskeletal rheumatic diseases. The recommendations discuss (1) the role of MRI in current classification criteria of musculoskeletal rheumatic diseases (including early diagnosis of inflammation, disease follow-up, and identification of disease complications); (2) the impact of MRI on the diagnosis of axial and peripheral spondyloarthritis, rheumatoid arthritis, and juvenile spondyloarthritis; (3) MRI protocols for the axial and peripheral joints; (4) MRI interpretation and reporting for axial and peripheral joints; and finally, (5) methods for assessing MR images including quantitative, semiquantitative, and dynamic contrast-enhanced MRI studies.

The Influence of High-Impact Exercise on Cortical and Trabecular Bone Mineral Content and 3D Distribution Across the Proximal Femur in Older Men: A Randomized Controlled Unilateral Intervention.

Regular exercisers have lower fracture risk, despite modest effects of exercise on bone mineral content (BMC). Exercise may produce localized cortical and trabecular bone changes that affect bone strength independently of BMC. We previously demonstrated that brief, daily unilateral hopping exercises increased femoral neck BMC in the exercise leg versus the control leg of older men. This study evaluated the effects of these exercises on cortical and trabecular bone and its 3D distribution across the proximal femur, using clinical CT. Fifty healthy men had pelvic CT scans before and after the exercise intervention. We used hip QCT analysis to quantify BMC in traditional regions of interest and estimate biomechanical variables. Cortical bone mapping localized cortical mass surface density and endocortical trabecular density changes across each proximal femur, which involved registration to a canonical proximal femur model. Following statistical parametric mapping, we visualized and quantified statistically significant changes of variables over time in both legs, and significant differences between legs. Thirty-four men aged mean (SD) 70 (4) years exercised for 12-months, attending 92% of prescribed sessions. In traditional regions of interest, cortical and trabecular BMC increased over time in both legs. Cortical BMC at the trochanter increased more in the exercise than control leg, whereas femoral neck buckling ratio declined more in the exercise than control leg. Across the entire proximal femur, cortical mass surface density increased significantly with exercise (2.7%; p < 0.001), with larger changes (> 6%) at anterior and posterior aspects of the femoral neck and anterior shaft. Endocortical trabecular density also increased (6.4%; p < 0.001), with localized changes of > 12% at the anterior femoral neck, trochanter, and inferior femoral head. Odd impact exercise increased cortical mass surface density and endocortical trabecular density, at regions that may be important to structural integrity. These exercise-induced changes were localized rather than being evenly distributed across the proximal femur.

Ganglia arising from the transverse acetabular ligament: a report of two cases.

Ganglia arising from the hip are rare. Its diagnosis is difficult owing to the anatomic location. A high index of suspicion and high-resolution imaging is essential to make the diagnosis. Treatment depends on the size, location, and symptoms. This report is of 2 patients with ganglia arising from the transverse acetabular ligament.

Isolated posterior high ankle sprain: a report of three cases.

High ankle sprains are difficult to diagnose and account for 10% of all ankle sprains. A high index of suspicion is essential for diagnosis. High ankle sprains are managed symptomatically, with prolonged rehabilitation. The posterior inferior tibiofibular ligament is the strongest syndesmotic ligament; isolated injury of it is rare. We present 3 cases of isolated posterior high ankle sprain and discuss the relevant anatomy, mechanism of injury, and management.

High impact exercise increased femoral neck bone mineral density in older men: a randomised unilateral intervention.

INTRODUCTION: There is little evidence as to whether exercise can increase BMD in older men with no investigation of high impact exercise. Lifestyle changes and individual variability may confound exercise trials but can be minimised using a within-subject unilateral design (exercise leg [EL] vs. control leg [CL]) that has high statistical power. PURPOSE: This study investigated the influence of a 12month high impact unilateral exercise intervention on femoral neck BMD in older men. METHODS: Fifty, healthy, community-dwelling older men commenced a 12month high impact unilateral exercise intervention which increased to 50 multidirectional hops, 7days a week on one randomly allocated leg. BMD of both femurs was measured using dual energy X-ray absorptiometry (DXA) before and after 12months of exercise, by an observer blind to the leg allocation. Repeated measures ANOVA with post hoc tests was used to detect significant effects of time, leg and interaction. RESULTS: Thirty-five men (mean±SD, age 69.9±4.0years) exercised for 12months and intervention adherence was 90.5±9.1% (304±31 sessions completed out of 336 prescribed sessions). Fourteen men did not complete the 12month exercise intervention due to: health problems or injuries unrelated to the intervention (n=9), time commitments (n=2), or discomfort during exercise (n=3), whilst BMD data were missing for one man. Femoral neck BMD, BMC and cross-sectional area all increased in the EL (+0.7, +0.9 and +1.2 % respectively) compared to the CL (-0.9, -0.4 and -1.2%); interaction effect P<0.05. Although the interaction term was not significant (P>0.05), there were significant main effects of time for section modulus (P=0.044) and minimum neck width (P=0.006). Section modulus increased significantly in the EL (P=0.016) but not in the CL (P=0.465); mean change +2.3% and +0.7% respectively, whereas minimum neck width increased significantly in the CL (P=0.004) but not in the EL (P=0.166); mean changes being +0.7% and +0.3% respectively. CONCLUSION: A 12month high impact unilateral exercise intervention was feasible and effective for improving femoral neck BMD, BMC and geometry in older men. Carefully targeted high impact exercises may be suitable for incorporation into exercise interventions aimed at preventing fractures in healthy community-dwelling older men.

Dynamic ultrasound assessment of the effects of knee and ankle position on Achilles tendon apposition following acute rupture.

BACKGROUND: Previous reports have suggested that knee flexion improves tendon edge apposition following acute rupture of the Achilles tendon. The aim of the present study was to determine, with use of ultrasonography, the effects of knee and ankle position on the Achilles tendon gap distance in patients with an acute rupture. METHODS: Twenty-six patients with a unilateral acute complete Achilles tendon rupture that had been confirmed with ultrasonography were recruited within a week after the injury. The mean age at the time of presentation was forty-one years. Ultrasound measurements included the location of the rupture and the gap distance between the superficial tendon edges with the ankle in neutral and the knee extended. The gap distance was sequentially measured with the foot in maximum equinus at the ankle and with 0°, 30°, 60°, and 90° of knee flexion. RESULTS: The mean distance of the rupture from the calcaneal enthesis was 52 mm (range, 40 to 76 mm). The mean gap distance with the ankle in neutral and the knee extended was 12 mm (95% confidence interval, 10 to 13 mm). This distance decreased to 5 mm (95% confidence interval, 4 to 7 mm) when the foot was placed in maximum ankle equinus with 0° of knee flexion and to 4 mm (95% confidence interval, 3 to 5 mm) with 30° of knee flexion, 3 mm (95% confidence interval, 2 to 4 mm) with 60° of knee flexion, and 2 mm (95% confidence interval, 1 to 2 mm) with 90° of knee flexion. Expressing the reduction in gap distance with each successive position as a percentage of the gap distance with the knee extended and the ankle in neutral revealed a mean reduction of 55.7%, 64.4%, 75.4%, and 84.8% with maximum ankle equinus and 0°, 30°, 60°, and 90° of knee flexion, respectively. The difference in gap distance between each of these positions was significant (p < 0.05). CONCLUSIONS: Maximum ankle equinus alone significantly reduces the gap distance after acute Achilles tendon rupture. Increasing knee flexion further reduces the gap distance by small increments that, although significant, may not be clinically important.

Magnetic resonance imaging assessment of spinal inflammation in ankylosing spondylitis: standard clinical protocols may omit inflammatory lesions in thoracic vertebrae.

OBJECTIVE: Radiologic assessment of spinal inflammation in patients with ankylosing spondylitis (AS) relies primarily on magnetic resonance imaging (MRI), although little is known about the distribution of inflammatory lesions within the structures of the spine. Our objective was to compare the distribution of inflammatory lesions centrally and laterally within the thoracic and lumbar spine vertebral bodies. METHODS: We studied 49 patients with AS who were scanned with STIR and T1-weighted spin-echo MRI of the whole spine. Scans were read by 2 musculoskeletal radiologists, with a third reader as the arbitrator. Controls included 6 age-matched individuals. We recorded bone marrow edema on STIR images from each vertebral body, separately identifying central and lateral slices. The latter were defined as images that included or were lateral to the pedicle. Interreader reproducibility was assessed by kappa statistics. RESULTS: Inflammation was present in 263 (45%) of 588 thoracic and 86 (35%) of 245 lumbar vertebrae; the mean number of affected thoracic and lumbar vertebrae per patient were 5.4 and 1.8, respectively. Inflammation was present in the lateral aspect of 219 (37%) of 588 thoracic vertebrae and 45 (18%) of 245 lumbar vertebrae (P < 0.001). Lesions were more common laterally than centrally for all thoracic vertebrae except for T7. Involvement of only the lateral slices was observed in as many as 19.6% of thoracic vertebrae. CONCLUSION: Evaluation of spinal inflammation by MRI may omit lesions in up to 20% of inflamed thoracic vertebrae if both scanning and image assessment do not include sagittal slices that extend to the lateral edges of all vertebrae.

Meniscal extrusion in young athletes: associated knee joint abnormalities.

OBJECTIVE: The objective of our study was to assess the rate of meniscal extrusion and its connection with common meniscal and joint abnormalities. MATERIALS AND METHODS: MR signs of meniscal extrusion were evaluated retrospectively in 24 rugby and soccer players (40 knees) who are currently free of pain in the knee, impaired mobility, and joint swelling. The control group consisted of 23 consecutive active individuals (36 knees) with no history of knee problems. The criterion for extrusion of the meniscus was defined as a distance of 3 mm or more between the peripheral border of the meniscus and the edge of the tibial plateau measured on coronal images. RESULTS: Forty-eight percent of the athletes' knees and 30% of the control subjects' knees showed evidence of meniscal extrusion. Among the athletes, a significant association between meniscal extrusion and joint effusion (11 cases), meniscal tears (seven cases), and anterior cruciate ligament (ACL) tear (four cases) was found (p < or = 0.004). In the control group, no significant association was found between meniscal extrusion and joint effusion (three cases), meniscal tears (four cases), and ACL tears (two cases) (p = 1.00). A significant association was not found between degenerative change and meniscal extrusion in either the athletes (p = 0.23) or the control subjects (p = 1.00). The most commonly associated knee abnormality was joint effusion in 73% of knees with meniscal extrusion in athletes. CONCLUSION: Meniscal extrusion is a common finding on MRI of athletes' knees. Meniscal extrusion in association with meniscal tear and joint effusion is postulated as a significant injury in athletes and its recognition as such in this group is important because it may prompt orthopedic intervention.