Proof-of-Concept Study of the Use of Accelerometry to Quantify Knee Joint Movement and Assist with the Diagnosis of Juvenile Idiopathic Arthritis

Juvenile idiopathic arthritis (JIA) is the most common rheumatic disease in childhood. Seven children and young people (CYP) with a diagnosis of JIA and suspected active arthritis of a single knee joint were recruited for this proof-of-concept study. The presence of active arthritis was confirmed by clinical examination. Four tri-axial accelerometers were integrated individually in elastic bands and placed above and below each knee. Participants performed ten periodic flexion-extensions of each knee joint while lying down, followed by walking ten meters in a straight path. The contralateral (non-inflamed) knee joint acted as a control. Accelerometry data were concordant with the results of clinical examination in six out of the seven patients recruited. There was a significant difference between the accelerometry measured range of movement (ROM, p-value = 0.032) of the knees with active arthritis and the healthy contralateral knees during flexion-extension. No statistically significant difference was identified between the ROM of the knee joints with active arthritis and healthy knee joints during the walking test. The study demonstrated that accelerometry may help in differentiating between healthy knee joints and those with active arthritis; however, further research is required to confirm these findings.

Ultrasonography of the bone surface in children: normal and pathological findings in the bone cortex and periosteum

Ultrasound (US) is widely used in pediatric musculoskeletal pathology at all ages. Although the focus is often on soft tissues, joints and cartilage, the examiner might be confronted with changes in the underlying bone surface that are important to understand and integrate in the diagnosis. This article illustrates the normal US aspects of the cortical bone surface and periosteum, as well as the most common US anomalies seen in infections, trauma and bone tumors in children.

Juvenile Idiopathic Arthritis: A Review of Novel Diagnostic and Monitoring Technologies

Juvenile idiopathic arthritis (JIA) is the most common rheumatic disease of childhood and is characterized by an often insidious onset and a chronic relapsing-remitting course, once diagnosed. With successive flares of joint inflammation, joint damage accrues, often associated with pain and functional disability. The progressive nature and potential for chronic damage and disability caused by JIA emphasizes the critical need for a prompt and accurate diagnosis. This article provides a review of recent studies related to diagnosis, monitoring and management of JIA and outlines recent novel tools and techniques (infrared thermal imaging, three-dimensional imaging, accelerometry, artificial neural networks and fuzzy logic) which have demonstrated potential value in assessment and monitoring of JIA. The emergence of novel techniques to assist clinicians' assessments for diagnosis and monitoring of JIA has demonstrated promise; however, further research is required to confirm their clinical utility.

Thermal and Visual Imaging to Assist with Juvenile Idiopathic Arthritis Examination of the Knees

Juvenile idiopathic arthritis (JIA) causes inflammation of the joints, and it is frequently associated with their pain and stiffness. Its timely diagnosis is important to avoid its progressive damage to the bones and cartilage. Increases in the joint’s temperature and redness could be indicators of active JIA, hence their accurate quantification could assist with diagnosis. Thermal and visual images of the knees in 20 JIA participants (age: mean = 11.2 years, standard deviation = 2.3 years) were studied. The median temperature of knees with active inflammation was 3.198% higher than that of inactive knees. This difference, examined by a Wilcoxon signed-rank test, was statistically significant (p = 0.0078). In six out of the eight participants who had one active inflamed knee, thermal imaging identified the corresponding knee as warmer. In 16 out of 20 participants, the knee identified as warmer by thermal imaging was also identified as having a greater colour change by visual imaging as compared to their respective reference regions. The devised methods could accurately quantify the colour and temperature of the knees. It was concluded that thermal and visual imaging methods can be valuable in examining JIA. Further studies involving a larger number of participants and more detailed explorations would be needed prior to clinical application.

The Role of Ultrasound in Juvenile Idiopathic Arthritis: A Narrative Review From an Imaging Perspective

Objective:

Musculoskeletal sonography (MSKS) is increasingly being used in the setting of juvenile idiopathic arthritis (JIA). The purpose of this narrative review was to describe the role of sonography in JIA and outline strategies for operators of pediatric MSKS.

Methods:

A literature review through multiple medical databases was conducted by restricting the search to medical subject headings (MeSH). Peer-reviewed English-language articles from 2007 to 2018 were included, which focused the on common sonographic findings of JIA.

Results:

Twenty-six articles were selected for inclusion in the study after a complete reading. Many studies aimed to address the validity of sonographic techniques in the assessment of JIA, but few studies discussed the specific sonographic appearances of JIA, scanning pitfalls, and appropriate imaging techniques.

Conclusion:

MSKS reveals subclinical manifestations of arthropathy, but the true value of detecting subclinical disease is not well understood. MSKS is limited in the evaluation of articular cartilage thinning and bony erosions. Responsiveness of MSKS in JIA remains to be formally assessed with higher quality studies.

Age dependent ultrasound B-mode findings of the elbow joint in healthy children and adolescents

Due to maturation of joints, various changes take place, not only in the field of paediatric rheumatology but also in paediatric orthopaedics musculoskeletal ultrasound plays an important role in both the diagnosis and the follow-up of diseases in this field. To differentiate between physiological and pathological findings, the knowledge of reference values of joint structures is indispensable. The objective was to define B-mode ultrasound age- and sex-related reference values for the elbow joint in healthy children and adolescents during maturation. In a cross-sectional, multicentre ultrasound study we examined both sides of the elbow joints of 437 healthy children and adolescents (194 boys/243 girls) being between one and less than 18 years old. The children were classified into six equal age groups and divided according to their gender. We measured the distance between the outer margin of the joint capsule and the bone surface to define the bone-capsule distance (BCD), the thickness of the joint cartilage as well as the thickness of the joint capsule. The bone-capsule junction zone and the shape of the joint capsule were analysed qualitatively. The bone capsule distance and the capsule thickness increased with age. In contrast, the joint cartilage thickness decreased. In most cases the junction zone was peaked. The joint capsule showed mostly a concave shape. Intra- and interobserver reliabilities were good. We propose B-mode ultrasound age- and sex-related reference values for the elbow joint in a large number of healthy children and adolescents for the first time. By applying these standard values to the ultrasound examination of the elbow joint, it may be possible to achieve greater certainty in the diagnosis of pathological processes.

Age-dependent arthrosonographic reference values of the hip joint in healthy children and adolescents - a cross-sectional multicenter ultrasound study

BACKGROUND

Musculoskeletal US is a noninvasive imaging method for diagnosing and monitoring inflammatory rheumatic diseases.

OBJECTIVES

To develop age- and gender-related arthrosonographic reference intervals for the hip joint of healthy children and adolescents.

MATERIALS AND METHODS

In a cross-sectional US study, we examined both hip joints of 445 children and adolescents with an age range of 1 year to 18 years. We measured the distance between the bone surface and the outer margin of the joint capsule to define the bone-capsule distance, the joint capsule and cartilage thickness, and the capsule layer thickness. Reference values were calculated. The shape of the joint capsule and bone-capsule junction zone were analyzed qualitatively. An intraobserver analysis was performed.

RESULTS

Bone-capsule distance, capsule thickness and the anterior capsule layer increase with age. In contrast, joint cartilage decreases. The posterior capsule layer exhibited constant thickness across all age groups. The difference between both body sides and gender was collectively less than 0.5 mm. The intraobserver variations were within the calculated reference intervals. The insertion of the capsule to the bone was mostly a peaked one. The capsule shape had a convex or straight configuration in a neutral position and a concave position during outward rotation. The intraobserver analysis revealed good to very good concordance.

CONCLUSION

We propose age- and gender-related reference intervals for the bone-capsule distance, joint capsule and cartilage thickness of the hip.

Joint Involvement in Children with Celiac Disease

OBJECTIVE

To determine early joint involvement as detected by ultrasonography in children with newly diagnosed celiac disease, and in children with celiac disease on gluten-free diet for more than 6 months.

METHODS

Cross-sectional comparative study evaluating joint abnormalities by ultrasonography.

Results

Ultrasonography showed abnormalities in 19 out of 60 (31.7%) children with newly diagnosed celiac disease as compared to 2 (3.3%) out of 60 in those on a gluten-free diet for more than 6 months.

CONCLUSION

Subclinical synovitis as detected by ultrasound is a frequent finding in newly diagnosed children with celiac disease.

Ultrasound imaging of synovial inflammation in juvenile idiopathic arthritis

Juvenile idiopathic arthritis (JIA) is the most common rheumatic entity of childhood. The hallmark feature of all subtypes is joint inflammation. Imaging is used to evaluate the extent and severity of inflammation, degree of joint damage and response to treatment, which in turn impacts patient management. Ultrasound has become a useful adjunct to clinical examination because it shows promise in evaluating clinical and subclinical inflammation (synovitis, enthesitis) as well as cartilage and bone erosive changes. However more collaborative research is needed to help define the normal appearance of the growing skeleton, clarify the significance of subclinical findings and develop useful definitions, imaging protocols and scoring systems of disease.

Ultrasound Examination of Pediatric Musculoskeletal Diseases and Neonatal Spine

Ultrasound (US) is a simple, non-invasive imaging modality which allows high-resolution imaging of the musculoskeletal (MSK) system. Its increasing popularity in pediatrics is due to the fact that it does not involve radiation, has an ability to visualize non-ossified cartilaginous and vascular structures, allows dynamic imaging and quick contralateral comparison. US is the primary imaging modality in some pediatric MSK conditions like infant hip in developmental dysplasia (DDH), hip joint effusion, epiphyseal trauma and evaluation of the neonatal spine. US is the modality of choice in infants with DDH, both in the initial evaluation and post-treatment follow-up. US has a sensitivity equivalent to MRI in evaluation of the neonatal spine in experienced hands and is a good screening modality in neonates with suspected occult neural tube defects. In other MSK applications, it is often used for the initial diagnosis or in addition to other imaging modalities. In trauma and infections, US can often detect early and subtle soft tissue abnormalities and a quick comparison with the contralateral side aids in diagnoses. Dynamic imaging is crucial in evaluating congenital instabilities and dislocations, soft tissue and ligamentous injuries, epiphyseal injuries and fracture separations. High-resolution imaging along with color Doppler (CD) is useful in the characterization of soft tissue masses. This article reviews the applications of US in pediatric MSK with emphasis on conditions where it is a primary modality. Limitations of US include inability to penetrate bone, hence, limited diagnosis of intraosseous pathology and operator dependency.

Ultrasound-guided corticosteroid injection of the subtalar joint for treatment of juvenile idiopathic arthritis

BACKGROUND

The subtalar joint is commonly affected in children with juvenile idiopathic arthritis and is challenging to treat percutaneously.

OBJECTIVE

To describe the technique for treating the subtalar joint with US-guided corticosteroid injections in children and young adults with juvenile idiopathic arthritis and to evaluate the safety of the treatment.

MATERIALS AND METHODS

We retrospectively analyzed 122 patients (age 15 months-29 years) with juvenile idiopathic arthritis who were referred by a pediatric rheumatologist for corticosteroid injection therapy for symptoms related to the hindfoot or ankle. In these patients the diseased subtalar joint was targeted for therapy, often in conjunction with adjacent affected joints or tendon sheaths of the ankle. We used a protocol based on age, weight and joint for triamcinolone hexacetonide or triamcinolone acetonide dose prescription. We describe the technique for successful treatment of the subtalar joint.

RESULTS

A total of 241 subtalar joint corticosteroid injections were performed under US guidance, including 68 repeat injections for recurrent symptoms in 26 of the 122 children and young adults. The average time interval between repeat injections was 24.8 months (range 2.2-130.7 months, median 14.2 months). Subcutaneous tissue atrophy and skin hypopigmentation were the primary complications observed. These complications occurred in 3.9% of the injections.

CONCLUSION

With appropriate training and practice, the subtalar joint can be reliably and safely targeted with US-guided corticosteroid injection to treat symptoms related to juvenile idiopathic arthritis.