Ultrasound and MRI of the foot in children and adolescents newly diagnosed with juvenile idiopathic arthritis.

Aim: To evaluate the spectrum of inflammatory features in foot joints which may be detected on routinely performed ultrasound (US) and magnetic resonance imaging (MRI) in children newly diagnosed with juvenile idiopathic arthritis (JIA). Material and methods: Two groups of children hospitalized in a reference center for rheumatology, newly diagnosed with JIA and suspected of foot involvement in the course of JIA were included in this retrospective study. In the first group of 47 patients aged 1-18 years, the imaging was restricted to US. The second group of 22 patients aged 5-18 years underwent only non-contrast MRI of the foot. Results: The most frequent pathologies seen on US included effusion and synovial thickening in the first metatarsophalangeal joint (MTP1), followed by the tibiotalar joint. Synovial hyperemia on color Doppler US images was present most frequently in the Chopart and midtarsal joints (64%; 7/11 cases), followed by the tibiotalar joint (45%; 5/11), and MTP2-5 joint synovitis (40%; 4/10). Grade 3 hyperemia was present only in four cases; grades 1 and 2 were detected in the majority of cases. On MRI, bone marrow edema was the most frequent pathology, found mostly in the calcaneus (45%; 10/22 cases), while alterations of the forefoot were rare. No cases of bursitis, enthesitis, cysts, erosions or ankylosis were diagnosed in either of the analyzed groups. Conclusions: Routine US of the foot is recommended for early detection of its involvement in JIA in daily clinical practice. Although MRI can identify features of various JIA stages, it is particularly useful for the detection of bone marrow alterations.

Clinical indications for image-guided interventional procedures in the musculoskeletal system: a Delphi-based consensus paper from the European Society of Musculoskeletal Radiology (ESSR)-part VII, nerves of the lower limb.

OBJECTIVES: To perform a Delphi-based consensus on published evidence on image-guided interventional procedures for peripheral nerves of the lower limb (excluding Morton's neuroma) and provide clinical indications. METHODS: We report the results of a Delphi-based consensus of 53 experts from the European Society of Musculoskeletal Radiology who reviewed the published literature for evidence on image-guided interventional procedures offered around peripheral nerves in the lower limb (excluding Morton's neuroma) to derive their clinical indications. Experts drafted a list of statements and graded them according to the Oxford Centre for evidence-based medicine levels of evidence. Consensus was considered strong when > 95% of experts agreed with the statement or broad when > 80% but < 95% agreed. The results of the Delphi-based consensus were used to write the paper. RESULTS: Nine statements on image-guided interventional procedures for peripheral nerves of the lower limb have been drafted. All of them received strong consensus. Image-guided pudendal nerve block is safe, effective, and well tolerated with few complications. US-guided perisciatic injection of anesthetic provides good symptom relief in patients with piriformis syndrome; however, the addition of corticosteroids to local anesthetics still has an unclear role. US-guided lateral femoral cutaneous nerve block can be used to provide effective post-operative regional analgesia. CONCLUSION: Despite the promising results reported by published papers on image-guided interventional procedures for peripheral nerves of the lower limb, there is still a lack of evidence on the efficacy of most procedures. KEY POINTS: • Image-guided pudendal nerve block is safe, effective, and well tolerated with few complications. • US-guided perisciatic injection of anesthetic provides good symptom relief in patients with piriformis syndrome; however, the addition of corticosteroids to local anesthetics still has an unclear role. • US-guided lateral femoral cutaneous nerve block can be used to provide effective post-operative regional analgesia. The volume of local anesthetic affects the size of the blocked sensory area.

Clinical indications for image-guided interventional procedures in the musculoskeletal system: a Delphi-based consensus paper from the European Society of Musculoskeletal Radiology (ESSR)-part VI, foot and ankle.

OBJECTIVES: Clarity regarding accuracy and effectiveness for interventional procedures around the foot and ankle is lacking. Consequently, a board of 53 members of the Ultrasound and Interventional Subcommittees of the European Society of Musculoskeletal Radiology (ESSR) reviewed the published literature to evaluate the evidence on image-guided musculoskeletal interventional procedures around this anatomical region. METHODS: We report the results of a Delphi-based consensus of 53 experts from the European Society of Musculoskeletal Radiology who reviewed the published literature for evidence on image-guided interventional procedures offered around foot and ankle in order to derive their clinical indications. Experts drafted a list of statements and graded them according to the Oxford Centre for evidence-based medicine levels of evidence. Consensus was considered strong when > 95% of experts agreed with the statement or broad when > 80% but < 95% agreed. The results of the Delphi-based consensus were used to write the paper that was shared with all panel members for final approval. RESULTS: A list of 16 evidence-based statements on clinical indications for image-guided musculoskeletal interventional procedures in the foot and ankle were drafted after a literature review. The highest level of evidence was reported for four statements, all receiving 100% agreement. CONCLUSION: According to this consensus, image-guided interventions should not be considered a first-level approach for treating Achilles tendinopathy, while ultrasonography guidance is strongly recommended to improve the efficacy of interventional procedures for plantar fasciitis and Morton's neuroma, particularly using platelet-rich plasma and corticosteroids, respectively. KEY POINTS: • The expert panel of the ESSR listed 16 evidence-based statements on clinical indications of image-guided musculoskeletal interventional procedures in the foot and ankle. • Strong consensus was obtained for all statements. • The highest level of evidence was reached by four statements concerning the effectiveness of US-guided injections of corticosteroid for Morton's neuroma and PRP for plantar fasciitis.

Development and Validation of a Multitask Deep Learning Model for Severity Grading of Hip Osteoarthritis Features on Radiographs.

Background A multitask deep learning model might be useful in large epidemiologic studies wherein detailed structural assessment of osteoarthritis still relies on expert radiologists' readings. The potential of such a model in clinical routine should be investigated. Purpose To develop a multitask deep learning model for grading radiographic hip osteoarthritis features on radiographs and compare its performance to that of attending-level radiologists. Materials and Methods This retrospective study analyzed hip joints seen on weight-bearing anterior-posterior pelvic radiographs from participants in the Osteoarthritis Initiative (OAI). Participants were recruited from February 2004 to May 2006 for baseline measurements, and follow-up was performed 48 months later. Femoral osteophytes (FOs), acetabular osteophytes (AOs), and joint-space narrowing (JSN) were graded as absent, mild, moderate, or severe according to the Osteoarthritis Research Society International atlas. Subchondral sclerosis and subchondral cysts were graded as present or absent. The participants were split at 80% (n = 3494), 10% (n = 437), and 10% (n = 437) by using split-sample validation into training, validation, and testing sets, respectively. The multitask neural network was based on DenseNet-161, a shared convolutional features extractor trained with multitask loss function. Model performance was evaluated in the internal test set from the OAI and in an external test set by using temporal and geographic validation consisting of routine clinical radiographs. Results A total of 4368 participants (mean age, 61.0 years ± 9.2 [standard deviation]; 2538 women) were evaluated (15 364 hip joints on 7738 weight-bearing anterior-posterior pelvic radiographs). The accuracy of the model for assessing these five features was 86.7% (1333 of 1538) for FOs, 69.9% (1075 of 1538) for AOs, 81.7% (1257 of 1538) for JSN, 95.8% (1473 of 1538) for subchondral sclerosis, and 97.6% (1501 of 1538) for subchondral cysts in the internal test set, and 82.7% (86 of 104) for FOS, 65.4% (68 of 104) for AOs, 80.8% (84 of 104) for JSN, 88.5% (92 of 104) for subchondral sclerosis, and 91.3% (95 of 104) for subchondral cysts in the external test set. Conclusion A multitask deep learning model is a feasible approach to reliably assess radiographic features of hip osteoarthritis. © RSNA, 2020 Online supplemental material is available for this article.

Juxta-Cortical Chondroma of the Phalanges: Is there a Role for Cone-Beam Computed Tomography in Diagnosis and Local Staging?: Main teaching point: Low-dose cone-beam computed tomography (CT) may be of additional value to radiographs and magnetic resonance imaging (MRI) in preoperative characterization and local staging of juxta-cortical chondroma.

Juxta-cortical chondroma is a rare cartilaginous tumor originating from the periosteum. On conventional radiography, the lesion typically causes saucerization of the adjacent cortex with well-delineated sclerotic margins. Projection radiography may be less accurate than cross-sectional imaging to demonstrate the precise extent of pressure erosion and bone and soft tissue extent. Although magnetic resonance imaging (MRI) is the imaging technique of choice for further preoperative evaluation, cone-beam computed tomography (CT) may be of additional value. Due to its high spatial resolution, cone-beam CT may detect very tiny matrix calcifications and allows a more precise evaluation of the saucerized cortex at a low radiation dose.

Clinical indications for musculoskeletal ultrasound updated in 2017 by European Society of Musculoskeletal Radiology (ESSR) consensus.

OBJECTIVES: To update the 2012 European Society of Musculoskeletal Radiology (ESSR) clinical consensus guidelines for musculoskeletal ultrasound referral in Europe. METHODS: Twenty-one musculoskeletal imaging experts from the ESSR participated in a consensus study based on a Delphic process. Two independent (non-voting) authors facilitated the procedure and resolved doubtful issues. Updated musculoskeletal ultrasound literature up to July 2017 was scored for shoulder, elbow, wrist/hand, hip, knee, and ankle/foot. Scoring of ultrasound elastography was included. The strength of the recommendation and level of evidence was scored by consensus greater than 67% or considered uncertain when the consensus was consensus less than 67%. RESULTS: A total of 123 new papers were reviewed. No evidence change was found regarding the shoulder. There were no new relevant articles for the shoulder, 10 new articles for the elbow, 28 for the hand/wrist, 3 for the hip, 7 for the knee, and 4 for the ankle/foot. Four new evidence levels of A were determined, one for the hip (gluteal tendons tears), one for the knee (meniscal cysts), one for the ankle (ankle joint instability), and one for the foot (plantar plate tear). There was no level A evidence for elastography, although for Achilles tendinopathy and lateral epicondylitis evidence level was B with grade 3 indication. CONCLUSIONS: Four new areas of level A evidence were included in the guidelines. Elastography did not reach level A evidence. Whilst ultrasound is of increasing importance in musculoskeletal medical practice, the evidence for elastography remains moderate. KEY POINTS: • Evidence and expert consensus shows an increase of musculoskeletal ultrasound indications. • Four new A evidence levels were found for the hip, knee, ankle, and foot. • There was no level A evidence for elastography.

Cone beam CT of the musculoskeletal system: clinical applications.

OBJECTIVES: The aim of this pictorial review is to illustrate the use of CBCT in a broad spectrum of musculoskeletal disorders and to compare its diagnostic merit with other imaging modalities, such as conventional radiography (CR), Multidetector Computed Tomography (MDCT) and Magnetic Resonance Imaging. BACKGROUND: Cone Beam Computed Tomography (CBCT) has been widely used for dental imaging for over two decades. DISCUSSION: Current CBCT equipment allows use for imaging of various musculoskeletal applications. Because of its low cost and relatively low irradiation, CBCT may have an emergent role in making a more precise diagnosis, assessment of local extent and follow-up of fractures and dislocations of small bones and joints. Due to its exquisite high spatial resolution, CBCT in combination with arthrography may be the preferred technique for detection and local staging of cartilage lesions in small joints. Evaluation of degenerative joint disorders may be facilitated by CBCT compared to CR, particularly in those anatomical areas in which there is much superposition of adjacent bony structures. The use of CBCT in evaluation of osteomyelitis is restricted to detection of sequestrum formation in chronic osteomyelitis. Miscellaneous applications include assessment of (symptomatic) variants, detection and characterization of tumour and tumour-like conditions of bone. TEACHING POINTS: • Review the spectrum of MSK disorders in which CBCT may be complementary to other imaging techniques. • Compare the advantages and drawbacks of CBCT compared to other imaging techniques. • Define the present and future role of CBCT in musculoskeletal imaging.