Imaging Assessment of Nontraumatic Pathologic Conditions at the Craniovertebral Junction: A Comprehensive Review.

Nontraumatic pathologic conditions of the craniovertebral junction encompass a range of conditions affecting the complex anatomy of this region without direct physical injury. These conditions include congenital syndromes that predispose individuals to ligamentous laxity, potentially leading to instability. Additionally, rare but noteworthy cases such as Grisel syndrome, a cause of pediatric torticollis, may arise without a traumatic trigger. Inflammatory diseases, including rheumatoid arthritis, ankylosing spondylitis, and crystal deposition, can lead to cervical instability and spinal cord compression. Infections at the upper cervical spine are dominated by tuberculosis, typically transmitted through hematologic or lymphatic routes with characteristic imaging findings. On the other hand, purulent bacterial infections in this area are rare. Furthermore, although tumors involving the structures of the craniovertebral junction are infrequent, they can lead to significant complications, albeit less frequently through cord compression and more commonly via pathologic fractures or subluxation. The craniocervical junction is a complex anatomic region comprising ligaments, bones, joints, and muscles that support the head's weight and enable its wide range of motion. Accurate recognition and understanding of the complex anatomy and the various nontraumatic pathologic conditions at the craniovertebral junction are pivotal for initiating timely and appropriate treatment strategies. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.

Relationship between spinal structural damage and sagittal balance in axial spondyloarthritis: Is the thoracic spine the starting point?

OBJECTIVES: To assess the relationship between spinal structural damage, sagittal balance parameters and spine curvatures in patients with axial spondyloarthritis (axSpA). MATERIAL AND METHODS: In this cross-sectional study, the pelvic and sagittal balance parameters were obtained through EOS® (Biospace, Paris, France). Patients were divided into three groups according to the modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS) tertiles (G1 ≤6, n = 36; G2: 6.1-31, n = 36; G3 >31, n = 35) and pelvic and sagittal parameters were compared across them. Multivariable regression analysis was performed to analyze the impact of spinal structural damage and of other factors on sagittal vertical axis (SVA), an important sagittal balance parameter. RESULTS: A total of 107 patients was included. G2 and 3 exhibited higher mean values of thoracic kyphosis T1-T12 when compared to G1 (10.5°(12.3) vs. 22.3°(17.3) vs. 35.2°(14.6), p < 0.001), and G3 demonstrated lumbar L1-S1 straightening compared to the other groups (55.7°(9) and 50.7°(19.8), G1 and G2, respectively, vs. 35.7°(13.2), p < 0.001). Mean SVA values showed an increasing gradient from G1 to G3 (21.6(25.1) vs. 41(44.3) vs. 84.3(47.2)mm, p < 0.001). In the multivariable regression, a one-unit increase in total mSASSS was associated with an average 0.8 mm higher SVA. CONCLUSIONS: Our data showed that more spinal structural damage is associated with a higher SVA, reflecting poorer sagittal balance. Patients with increasing spinal damage have an important increase in thoracic kyphosis suggesting that postural modifications in patients with axSpA might have their origin in the thoracic spine.

Painless and painful synovitis have similar ultrasound and clinical outcomes: one-year cohort study in longstanding rheumatoid arthritis women patients.

OBJECTIVES: We aimed to compare the painless synovitis evolution with painful synovitis, based on bone erosion by ultrasonography over a year in women with longstanding rheumatoid arthritis. Ultrasound inflammatory measurements and radiographic, functional and clinical findings were also compared between groups at the end of the same follow-up. METHODS: A prospective cohort study was rolled out, involving 60 women with RA, divided into two groups: painless and painful, with 30 patients in each group. The wrist and MCPs joints were assessed by ultrasound and plain x-ray, initially and after 12 months (T0 and T12). There was also a clinical assessment (activity scores, functional tests, disease and treatment progression variables) at 6 and 12 months. RESULTS: Patients' average age was 58.0±12.8 and average length of disease 16.4±9.8 years. Initially, the demographic characteristics were similar between groups, however, the painful group had worse clinical and functional scores. There were no statistically significant differences in the majority of US bone erosions and US inflammatory measurements, nor in radiographic progression variables between the groups. Over one year, pinch strength test and DAS 28 remained worse in the painful group (p<0.05). Clinical worsening variables and change of treatment evolved similarly between the groups, on T6 and T12. CONCLUSIONS: According to the study, the painless group progressed similarly to the painful one over a year, as regards bone erosion, ultrasound inflammatory measurements, radiographic findings, clinical worsening and change of treatment in female longstanding RA patients.

The development of the intercondylar notch in the pediatric population.

BACKGROUND: Anterior cruciate ligament (ACL) repair is increasing in frequency in younger children. Recognition of the normal development of the intercondylar notch is important for successful ACL graft placement, allowing surgeons to better understand the anatomy and risk factors related to ACL tears and its reconstruction. The purpose of this study was to compile normative data on the intercondylar notch in the pediatric population with magnetic resonance imaging (MRI), emphasizing the differences between males and females. METHODS: In this retrospective study, musculoskeletal radiologists evaluated intercondylar notch width, bicondylar distance and notch width index (NWI). A total of 253 MRI examinations (130 males and 123 females between six and 18 years of age) were included. The association between measurements, sex and age was considered. Linear and fractional polynomial regression models were used to evaluate the relationships between measurements. RESULTS: Intercondylar notch width increased up to 10 years of age in females and 11 years of age in males, with relative stabilization up to 13 years in girls and 14 years in boys and a slight reduction in values at subsequent ages. Bicondylar distance showed significant progressive growth with age in both sexes. NWI showed a discrete and homogenous reduction with age in both sexes. CONCLUSION: Intercondylar notch width interrupts its growth around 10-11 years of age, with relative stabilization up to 13-14 years and a slight reduction in dimensions in subsequent ages. This growth pattern resembles the development of the ACL area observed in recent studies.

Radiography, CT, and MRI of Hip and Lower Limb Disorders in Children and Adolescents.

Infants and children are vulnerable to congenital and developmental hip and lower extremity disorders. These disorders have diverse causes in pediatric patients, and owing to potential related complications that can lead to degenerative disease in adulthood, an accurate diagnosis is essential. A common disease is developmental dysplasia of the hip, which affects nearly 1% of newborns. This condition is best evaluated with US and conventional radiography. Slipped capital femoral epiphysis affects approximately 0.01% of young teenagers and is initially evaluated with radiography. Femoroacetabular impingement is a risk factor for early osteoarthritis and can be assessed with radiography, CT, or MRI. Limb length discrepancy is defined as a greater than 2-cm difference in length between paired bilateral lower extremities. There are several methods of measuring this difference, and the use of an accurate imaging modality is essential for treatment. Developmental bowing is a physiologic condition involving varus angulation of the knee and is best evaluated by using conventional radiography. Blount disease is a progressive pathologic genu varum centered at the tibia; the three subtypes are infantile, juvenile, and adolescent. In- and out-toeing disorders are caused by abnormal tibial and femoral torsion that usually self-corrects during lower limb growth. The ability to recognize these conditions is essential for differentiating those that will resolve spontaneously versus those that will require treatment. The imaging features of congenital and developmental hip and lower extremity disorders are reviewed, with emphasis on diagnosis, radiologic assessment, associated findings, and classification. ©RSNA, 2019.

Diagnostic Imaging of Inflammatory Myopathies: New Concepts and a Radiological Approach.

PURPOSE OF REVIEW: The purpose of this review article is to highlight the current role of diagnostic imaging in the assessment of inflammatory myopathies. RECENT FINDINGS: Recent research demonstrates that imaging plays an important role in evaluating patients with symptoms of an inflammatory myopathy. In general, MRI is the pivotal imaging modality for assessing inflammatory myopathies, revealing precise anatomic details because of changes in the signal intensity of the muscles. Whole-body MR imaging has become increasingly important over the last several years. US is also a valuable imaging modality for scanning muscles. Together with the clinical history, familiarity with the imaging features of inflammatory myopathies is essential for formulating an accurate diagnosis.

Radiologic Manifestations of Musculoskeletal Sarcoidosis.

PURPOSE OF REVIEW: The purpose of this review article is to present the spectrum of abnormalities and multi-modality imaging evaluations in patients with musculoskeletal sarcoidosis. RECENT FINDINGS: The articular manifestations of sarcoidosis are difficult to distinguish from those of the other inflammatory and degenerative arthropathies, and the muscular lesions in sarcoidosis are generally clinically silent and therefore often missed. Magnetic resonance imaging has shown these manifestations to be very common in active sarcoidosis, and should thus be included in the screening if musculoskeletal sarcoidosis is suspected. The clinician should consider magnetic resonance imaging for the evaluation of patients with sarcoidosis who have unexplained osteoarticular complaints if standard radiographs are negative. Furthermore, radiologists should include sarcoidosis in the differential diagnosis of musculoskeletal disease detected at magnetic resonance imaging in the appropriate clinical setting.

The development of the anterior cruciate ligament in the paediatric population.

PURPOSE: The aim of this study was to retrospectively compile normative data on the anterior cruciate ligament (ACL) in the paediatric population with magnetic resonance imaging, emphasizing the differences between men and women. METHODS: In this retrospective study, musculoskeletal radiologists evaluated length, area, coronal and sagittal inclination of the ACL and inclination of the intercondylar notch. A total of 253 MR examinations (130 males and 123 females between 6 and 18 years of age) were included. The association between measurements, sex and age was considered. Linear and fractional polynomial regression models were used to evaluate the relationships between measurements. RESULTS: ACL length showed significant progressive growth (p < 0.001) with age in men and women, without characterization of growth peaks. ACL area in women showed more pronounced growth up to 11 years, stabilized from 11 to 14 years and then sustained a slight reduction. In men, ACL area showed more pronounced growth up to 12 years, stabilized from 12 to 15 years and then sustained slight reduction. Coronal and sagittal inclination of the ACL showed a significant progressive increase (p < 0.001) with age in both sexes, progressively verticalizing. The intercondylar roof inclination angle showed significant progressive reduction (p < 0.001) with age in both sexes. CONCLUSION: The area of the ACL does not accompany skeletal maturation, interrupting its growth around 11-12 years. Progressive verticalization of the ACL as well as of the intercondylar notch roof in the evaluated ages was also observed. The clinical relevance of this study is that the ACL presents different angular and morphologic changes during growth in the paediatric population. Since ACL repair is now being performed on younger children, recognition of the normal developmental changes of the ACL is of utmost importance for successful ACL graft placement. LEVEL OF EVIDENCE: III.

Femoral Component Axial Rotation in the Gap-Balancing Approach to Total Knee Arthroplasty: Measurement by Computed Tomography.

BACKGROUND: Rotational malalignment of total knee arthroplasty (TKA) is a potential cause for revision surgery; therefore, it is important to have valid criteria for evaluation of normal component rotational alignment. Because computed tomography (CT) is considered the most accurate method to assess the rotational alignment of prosthetic components, the objectives in this study were define the femoral component (FC) rotation by measuring the posterior condylar angle (PCA) and the condylar twist angle (CTA) in a patient population that underwent gap-balancing TKA; determine the reliability of the FC rotation by using these measurements; evaluate the inter-relationship between the PCA and CTA; and finally evaluate the frequency and agreement in identification of the medial epicondyle sulcus (MES). METHODS AND RESULTS: In this retrospective study, 2 radiologists examined 50 CT scans. Mean PCA values of -2.26° and -2.56° (internal rotation) and CTA values of -5.54° and -6.28° (internal rotation) were attained by 2 observers with a higher interobserver concordance for the PCA. Both measurements were considered to be reliable. There was moderate interobserver agreement for MES identification, with the MES present in 64% and 78% of patients, as identified by 2 observers. CONCLUSION: Mean FC rotation values as evaluated by PCA were -2.26° and -2.56° and as evaluated by CTA were -5.54° and -6.28°. PCA and CTA measurement by CT is reliable; however, the use of PCA is preferable because of the higher observer concordance. PCA can be inferred by subtracting 3° or 4° from the CTA. MES was identified in 64% and 78% of patients, with only moderate interobserver agreement.

Sacroiliac Joint Magnetic Resonance Imaging in Asymptomatic Patients with Recurrent Acute Anterior Uveitis: A Proof-of-concept Study.

OBJECTIVE: Our aim was to quantify bone marrow edema (BME) and/or structural lesions in the sacroiliac joints (SIJ) of patients with recurrent acute anterior uveitis (rAAU) with or without back pain, to evaluate the frequency of axial (axSpA) and peripheral spondyloarthritis (pSpA) and to establish which criterion for magnetic resonance imaging (MRI) positivity best reflected the global assessment of SIJ MRI. METHODS: A total of 50 patients with rAAU without prior rheumatologic diagnosis were included in our cross-sectional study, and these patients were compared to 21 healthy volunteers. SIJ MRI scans were read by 2 rheumatologists according to the Spondyloarthritis Research Consortium of Canada (SPARCC/MORPHO) protocol. Discrepant cases were adjudicated by a radiologist. RESULTS: Patients with rAAU were diagnosed with axSpA (Group 1, n = 20, 40%) and nonspecific back pain (Group 2, n = 6, 12%), or as being asymptomatic (Group 3, n = 24, 48%). Group 3 results showed 9 patients (37.5%) had SIJ MRI and/or were radiography-positive for axSpA (5 MRI and radiograph, 1 MRI, 3 radiograph). SIJ MRI scans that were compatible with SpA in groups 1 (n = 12) and 3 (n = 6) were similar in acute and structural lesions that were analyzed according to SPARCC/MORPHO. The best sensitivity/specificity criterion for defining a positive global MRI assessment was a BME score ≥ 3 (88%/94%). CONCLUSION: This is the first study evaluating SIJ MRI in patients with rAAU without back symptoms, showing positive findings for sacroiliitis. Moreover, a BME score ≥ 3 had better performance to define an SIJ MRI as positive for axSpA.

A new musculoskeletal ultrasound scoring system (US10) of the hands and wrist joints for evaluation of early rheumatoid arthritis patients.

OBJECTIVE: To propose a novel ultrasound scoring system for hand and wrist joints (US10) for evaluation of patients with early rheumatoid arthritis (RA) and to correlate the US10 with clinical, laboratory and functional variables. METHODS: Forty-eight early RA patients underwent clinical and laboratory evaluations as well as blinded ultrasound (US) examinations at baseline, three, six and 12 months. The proposed US10 system involved the assessment of the wrist, second and third metacarpophalangeal and proximal interphalangeal joints. The score consisted of inflammation parameters (synovial proliferation [SP], power Doppler [PD] and tenosynovitis [TN]) and joint damage parameters (bone erosion [BE] and cartilage damage [CD]). SP, PD, BE and CD were scored qualitatively (0-1) and semi-quantitatively (grades 0-3). Tenosynovitis was scored as presence/absence. The evaluation also involved the 28-Joint Disease Activity Score (DAS28), Health Assessment Questionnaire (HAQ) and C-reactive protein level (CRP). RESULTS: Mean duration of symptoms was 7.58±3.59 months. Significant correlations (p<0.05) were found between inflammation parameters and CRP at baseline and between the changes in these variables throughout the study. Significant correlations (p<0.05) were found between DAS28 score and both PD and TN at baseline and between the changes in DAS28 score and both SP and TN throughout the follow up. Moreover, significant correlations were found between the changes in inflammation parameter scores and HAQ score throughout the follow up. CONCLUSION: The proposed US10 scoring system proved to be a useful tool for monitoring inflammation and joint damage in early RA patients, demonstrating significant correlations with longitudinal changes in disease activity and functional status.

A new musculoskeletal ultrasound scoring system (US10) of the hands and wrist joints for evaluation of early rheumatoid arthritis patients / Novo sistema de escore ultrassonográfico (US10) musculoesquelético das articulações das mãos e punho para avaliação de pacientes com artrite reumatoide em fase inicial

ABSTRACT Objective: To propose a novel ultrasound scoring system for hand and wrist joints (US10) for evaluation of patients with early rheumatoid arthritis (RA) and to correlate the US10 with clinical, laboratory and functional variables. Methods: Forty-eight early RA patients underwent clinical and laboratory evaluations as well as blinded ultrasound (US) examinations at baseline, three, six and 12 months. The proposed US10 system involved the assessment of the wrist, second and third metacarpophalangeal and proximal interphalangeal joints. The score consisted of inflammation parameters (synovial proliferation [SP], power Doppler [PD] and tenosynovitis [TN]) and joint damage parameters (bone erosion [BE] and cartilage damage [CD]). SP, PD, BE and CD were scored qualitatively (0–1) and semi-quantitatively (grades 0–3). Tenosynovitis was scored as presence/absence. The evaluation also involved the 28-Joint Disease Activity Score (DAS28), Health Assessment Questionnaire (HAQ) and C-reactive protein level (CRP). Results: Mean duration of symptoms was 7.58 ± 3.59 months. Significant correlations (p < 0.05) were found between inflammation parameters and CRP at baseline and between the changes in these variables throughout the study. Significant correlations (p < 0.05) were found between DAS28 score and both PD and TN at baseline and between the changes in DAS28 score and both SP and TN throughout the follow up. Moreover, significant correlations were found between the changes in inflammation parameter scores and HAQ score throughout the follow up. Conclusion: The proposed US10 scoring system proved to be a useful tool for monitoring inflammation and joint damage in early RA patients, demonstrating significant correlations with longitudinal changes in disease activity and functional status.

RESUMO Objetivo: Propor um novo sistema de escore ultrassonográfico das articulações da mão e punho (US10) para a avaliação de pacientes com artrite reumatoide (AR) e correlacionar o US10 com variáveis clínicas, laboratoriais e funcionais. Métodos: Foram submetidos 48 pacientes com AR em fase inicial a avaliações clínicas e laboratoriais, bem como a exames cegos de ultrassom (US) no início do estudo e com 3, 6 e 12 meses. O sistema US10 proposto envolveu a avaliação do punho e das articulações metacarpofalângicas e interfalângicas proximais do segundo e terceiro dígitos. O escore consistiu em parâmetros inflamatórios (proliferação sinovial [PS], Power Doppler [PD] e tenossinovite [TN]) e parâmetros de danos articulares (erosão óssea [EO] e danos na cartilagem [DC]). PS, PD, EO e DC foram pontuados qualitativamente (0 a 1) e semiquantitativamente (graus 0 a 3). A tenossinovite foi pontuada como presença/ausência. A avaliação envolveu também o escore 28-Joint Disease Activity (DAS28), o Health Assessment Questionnaire (HAQ) e o nível de proteína C-reativa (PCR). Resultados: A duração média dos sintomas foi de 7,58 ± 3,59 meses. Foram encontradas correlações estatisticamente significativas (p < 0,05) entre os parâmetros de inflamação e a PCR no início do estudo e entre as mudanças nessas variáveis ao longo do estudo. Foram encontradas também correlações significativas (p < 0,05) entre o escore DAS28 e a PD e TN no início do estudo e entre as mudanças no escore DAS28 e PS e TN em todo o seguimento. Além disso, foram encontradas correlações significativas entre as mudanças no escore dos parâmetros de inflamação e no escore HAQ ao longo do seguimento. Conclusão: O sistema de escore US10 proposto provou ser uma ferramenta útil para monitorar a inflamação e o dano articular em pacientes com AR em fase inicial, demonstra correlações significativas com as alterações longitudinais na atividade da doença e no estado funcional.

A sonographic technique to evaluate the anterior bundle of the ulnar collateral ligament of the elbow: imaging features and anatomic correlation.

OBJECTIVES: The aim of this study was to test a sonographic technique used to view the anterior bundle of the ulnar collateral ligament (UCL), describe its sonographic characteristics in healthy volunteers, and verify these characteristics by determining interobserver variability and their correlations in cadavers. METHODS: Sonographic studies of the anterior bundle of the UCL were performed on 48 elbows of asymptomatic healthy volunteers. The participants were examined by 3 experts, who identified the insertion sites of the anterior bundle and subjectively evaluated its echogenicity and echo texture. A sonographic examination of the anterior bundle of the UCL in a cadaveric elbow was performed, and the same aspects were evaluated. RESULTS: In all cases, the anterior bundle of the UCL appeared as a triangular structure in the coronal plane and had a hyperechoic homogeneous echo texture in most of these cases. The cadaveric elbow had the same sonographic characteristics as the volunteers. CONCLUSIONS: As shown by examining the interobserver variability and determining the correlation with cadaveric tissue, sonography proved to be a reliable tool for evaluating the normal aspects of the anterior bundle of the UCL.

Ultrasound characteristics of gouty tophi in the olecranon bursa and evaluation of their reproducibility.

OBJECTIVES: To describe the ultrasound characteristics of gouty tophi in the olecranon bursa and to evaluate their reproducibility. METHODS: A prospective study of the ultrasound features of 35 sites of tophi nodulations in the elbows of 31 men (mean 54.6 years). The findings were evaluated dynamically following pre-established standards. The static images were evaluated by another radiologist and were reviewed by the first examiner. RESULTS: The most frequent characteristics of tophi are: hyperechogenicity (91.7%), poorly defined contours (88.6%), multiple grouped nodules (85.6%) and heterogeneity (68.6%). Intra-observer agreement is almost perfect for echogenicity (K = 1.0), moderate for the involvement of the olecranon bursa (K = 0.47) and fair for other characteristics. Inter-observer agreement is substantial for the echogenicity (K = 0.65), fair for the echotexture (K = 0.27) and the presence of a perilesional hypoechoic halo (K = 0.34) and slight for other characteristics. CONCLUSIONS: The most frequent characteristic of tophi is hyperechogenicity. The intra-observer and inter-observer concordance for echogenicity are almost perfect and substantial, respectively. Knowledge of characteristics of the tophi in the elbow and their intra and inter-observer reproducibility may assist in establishing parameters for monitoring treatment and setting up criteria for differential diagnosis of processes involving the olecraneon bursa.

Ultrasound features of tophi in chronic tophaceous gout.

OBJECTIVE: To describe the different and lesser-known ultrasound features of tophi in chronic tophaceous gout. METHODS: Ultrasound images of 138 affected areas were analyzed from 31 patients with gout, using high-quality broadband linear transducers (frequency range of 8-14 MHz). Tophi were classified relative to echogenicity, echotexture, contours, number and the presence or absence of hypoechoic halo. The duration of illness was correlated with the presence of calcifications in tophi. RESULTS: Hyperechoic tophi were seen in 133 areas (96.3%); these were most frequently hyperechoic and heterogeneous (37.6%) or hyperechoic and heterogeneous with calcification (32.6%). Contours were found to be poorly defined in 115 (83.3%) areas. Multiple grouped tophi were seen in 85 areas (61.6%) and 50 areas (36.2%) had individual tophi. In 77 examined areas (55.8%), there was a hypoechoic halo around the tophi. There was no correlation between illness duration and presence of calcifications on tophi. CONCLUSIONS: Tophi are generally hyperechoic, heterogeneous, with poorly defined contours, multiple grouped and surrounded by an anechoic halo. Individual tophus and the absence of association between illness duration and the presence of calcification are newly described features. This study of tophaceous gout by ultrasound may contribute to the diagnostic elucidation of patients with clinically atypical gout and show its diverse characteristic forms of presentation.

Melorheostosis of the thumb and trapezium bone.

Melorheostosis of the hand is rare. We report a 28-year-old woman with persistent pain associated with a slowly growing mass on the dorsum of the right thumb. The radiographs, computed tomography, and magnetic resonance imaging were used to examine characteristic of melorheostosis involving the trapezium bone, first metacarpal, and proximal phalange. The lesions underwent a surgical debulking of the hyperostotic cortex and a cortical fenestration.

Sclerotic metaphyseal lines in children and adolescents treated with alendronate.

INTRODUCTION: Bisphosphonates inhibit bone resorption by interfering with the action of osteoclasts. Among the adverse effects, sclerotic lines observed in the metaphysis of long bones have been described as the main imaging finding in pediatric patients. OBJECTIVE: To evaluate the frequency of radiographic changes caused by alendronate in children and adolescents with low bone density or calcinosis. PATIENTS AND METHODS: We conducted a cross-sectional study with 21 patients who were treated with once-weekly alendronate for at least 10 months. Patients underwent x-rays of long bones before the start of alendronate and approximately one year after its use. RESULTS: Eleven patients (52.3%) had sclerotic lines in the metaphysis of long bones. The most frequent site was the tibia (8/11 patients), followed by the femur (7/11), humerus (6/11), radius (4/11), ulna (3/11), and fibula (2/11). Regression of radiographic changes during the study period (up to 1.1 years after discontinuation of alendronate) was not observed. CONCLUSION: If used carefully, alendronate is safe and radiographic changes have not been shown to be clinically relevant.