The role of sacro-iliac joint magnetic resonance imaging in the diagnosis of axial spondyloarthritis: focus on differential diagnosis in women.

OBJECTIVE: To review the role of sacro-iliac magnetic resonance imaging (MRI) in the diagnosis of axial spondyloarthritis (AxSpA), with a focus on gender differences. METHODS: The experience of the authors and the results of an informal literature review are reported. RESULTS: Inflammatory changes of the sacro-iliac joint are the hallmark of AxSpA. Early, non-radiographic sacroiliitis may be diagnosed with MRI through the assessment of bone marrow edema (BMO) as well as concomitant structural damage. The MRI protocol should include three necessary sequences, i.e., fat-saturated T2-weighted sequences on two orthogonal planes, T1-weighted semi-coronal sequence, and fat-suppressed T1-weighted semi-coronal sequence. Inflammatory changes comprise required signs (BMO and/or osteitis) and additional signs, including synovitis (better defined as joint space enhancement), enthesitis, and capsulitis. Structural changes consist of erosions, sclerosis, fat metaplasia, and ankylosis. Due to mechanical axial strain, inflammatory changes in the sacro-iliac joint can be found in healthy individuals, runners, and patients with nonspecific low back pain. The prevalence of BMO is higher in women during pregnancy and postpartum, even 12 months after childbirth, but the extent and distribution of MRI findings may help in the differential diagnosis. Other challenges in the MRI diagnosis of sacroiliitis are subchondral T2 hyperintensity during developmental age, periarticular sclerosis in healthy subjects, or osteitis condensans ilii, and several pathological conditions that may mimic AxSpA, some of which are more frequently found in women. CONCLUSIONS: The described diagnostic challenges impose a multidisciplinary approach combining imaging findings with clinical and laboratory data.

Deep learning-based classification of erosion, synovitis and osteitis in hand MRI of patients with inflammatory arthritis.

OBJECTIVES: To train, test and validate the performance of a convolutional neural network (CNN)-based approach for the automated assessment of bone erosions, osteitis and synovitis in hand MRI of patients with inflammatory arthritis. METHODS: Hand MRIs (coronal T1-weighted, T2-weighted fat-suppressed, T1-weighted fat-suppressed contrast-enhanced) of rheumatoid arthritis (RA) and psoriatic arthritis (PsA) patients from the rheumatology department of the Erlangen University Hospital were assessed by two expert rheumatologists using the Outcome Measures in Rheumatology-validated RA MRI Scoring System and PsA MRI Scoring System scores and were used to train, validate and test CNNs to automatically score erosions, osteitis and synovitis. Scoring performance was compared with human annotations in terms of macro-area under the receiver operating characteristic curve (AUC) and balanced accuracy using fivefold cross-validation. Validation was performed on an independent dataset of MRIs from a second patient cohort. RESULTS: In total, 211 MRIs from 112 patients (14 906 region of interests (ROIs)) were included for training/internal validation using cross-validation and 220 MRIs from 75 patients (11 040 ROIs) for external validation of the networks. The networks achieved high mean (SD) macro-AUC of 92%±1% for erosions, 91%±2% for osteitis and 85%±2% for synovitis. Compared with human annotation, CNNs achieved a high mean Spearman correlation for erosions (90±2%), osteitis (78±8%) and synovitis (69±7%), which remained consistent in the validation dataset. CONCLUSIONS: We developed a CNN-based automated scoring system that allowed a rapid grading of erosions, osteitis and synovitis with good diagnostic accuracy and using less MRI sequences compared with conventional scoring. This CNN-based approach may help develop standardised cost-efficient and time-efficient assessments of hand MRIs for patients with arthritis.

Modified pustulotic arthro-osteitis diagnostic guidance 2022 - Modified Sonozaki criteria - Secondary publication.

The concept of pustulotic arthro-osteitis (PAO) was first reported by Sonozaki et al. in 1979, with diagnostic criteria (Sonozaki criteria) proposed in 1981. These criteria have served as the gold standard for PAO diagnosis for over 40 years. In recent years, there has been an increasing emphasis on maximizing the quality of life of patients with PAO. This is achieved by striving for clinical remission, structural remission, and functional remission through early diagnosis and appropriate therapeutic intervention from an early stage. This article is an English translation of a summary of the 'Modified PAO Diagnostic Guidance 2022', edited by the Japan Ministry of Health, Labour and Welfare's Research Group on improvement of medical standard and quality of life of patients with spondyloarthritis and related diseases represented by ankylosing spondylitis and the Japan Spondyloarthritis Society. This guidance is intended to be helpful to both Japanese and global communities in rheumatology and spondyloarthritis.

Characterization of bone marrow lesions in axial spondyloarthritis using quantitative T1 mapping MRI.

OBJECTIVE: Conventional magnetic resonance imaging (MRI) uses T1-weighted and short-tau inversion recovery (STIR) sequences to characterize bone marrow in axial spondyloarthritis. However, quantification is restricted to estimating the extent of lesions because signal intensities are highly variable both within individuals and across patients and MRI scanners. This study evaluates the performance of quantitative T1 mapping for distinguishing different types of bone marrow lesions of the sacroiliac joints. MATERIALS AND METHODS: In this prospective study, 62 patients underwent computed tomography (CT) and MRI of the sacroiliac joints including T1, STIR, and T1 mapping. Bone marrow lesions were characterized by three readers and assigned to one of four groups: sclerosis, osteitis, fat lesions, and mixed marrow lesions. Relaxation times on T1 maps were compared using generalized estimating equations and receiver operating characteristics (ROC) analysis. RESULTS: A total of 119 lesions were selected (sclerosis: 38, osteitis: 27, fat lesions: 40; mixed lesions: 14). T1 maps showed highly significant differences between the lesions with the lowest values for sclerosis (1516±220 ms), followed by osteitis (1909±75 ms), and fat lesions (2391±200 ms); p<0.001. T1 mapping differentiated lesions with areas under the ROC curve of 99% (sclerosis vs. osteitis) and 100% (other comparisons). CONCLUSION: T1 mapping allows accurate characterization of sclerosis, osteitis, and fat lesions at the sacroiliac joint but only for homogeneous, non-mixed lesions. Thus, further sequence development is needed before implementation in clinical routine.

Osteitis pubis following holmium laser enucleation of the prostate.

Osteitis pubis is a rare, inflammatory condition involving the pubic symphysis. While osteitis pubis has been reported following many urological procedures, including those addressing bladder outlet obstruction such as transurethral resection of the prostate, it has never been reported after holmium laser enucleation of the prostate (HoLEP). Here, we detail the clinical course of a patient found to have osteitis pubis following HoLEP. This patient presented several weeks after surgery with non-specific, persistent symptoms of groin pain and difficulty ambulating, alerting our clinicians to consider osteitis pubis which was confirmed on MRI of the pelvis. While the majority of osteitis pubis cases are managed with locally invasive techniques, our patient's symptoms were successfully managed conservatively with Foley catheter placement, oral antibiotics and close follow-up. At 9 months postoperative, the patient has reported complete resolution of symptoms and continues to be followed closely.

Prospective Comparison of the Imaging Value of 99m Tc-MDP Bone Scan and 68 Ga-FAPI-04 PET/CT in Synovitis, Acne, Pustulosis, Hyperostosis, and Osteitis Syndrome.

PURPOSE: This study aimed to explore the imaging value of 68 Ga-FAPI-04 PET/CT in synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome and compare it with that of 99m Tc-MDP bone scan. METHODS: Nineteen participants with SAPHO syndrome underwent 68 Ga-FAPI-04 PET/CT and 99m Tc-MDP bone scan. Demographic data and clinical features were recorded, SAPHO imaging features were analyzed, and the osteoarticular lesion detection rate in both methods was calculated. RESULTS: This prospective study recruited 4 men and 15 women aged 52.4 ± 8.6 years. The anterior chest wall was involved in all participants (100%). Palmoplantar pustulosis was the most common (36.8%) skin symptom. 99m Tc-MDP bone scan and 68 Ga-FAPI-04 PET/CT together detected 84 osteoarticular lesions, of which 91.7% (77/84) were detected by the former and 96.4% (81/84) by the latter. Furthermore, 68 Ga-FAPI-04 PET/CT detected 5 cases of knee and hip joint synovitis. CONCLUSIONS: 68 Ga-FAPI-04 PET/CT was more sensitive than 99m Tc-MDP bone scan when evaluating osteoarticular lesions in SAPHO syndrome and could also evaluate synovial lesions. 68 Ga-FAPI-04 PET/CT could be a good imaging method for SAPHO syndrome but requires further verification in a more extensive research cohort.

Synovitis, acne, pustulosis, hyperostosis, and osteitis syndrome with cranial bone involvement: Case report and literature review.

Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome is a rare autoimmune inflammatory disease characterized by osteoarticular and dermatological manifestations. The most common osteoarticular manifestations involve the anterior chest wall, axial skeleton, and long bones. Cranial bone involvement is less reported in SAPHO syndrome. We herein present three cases of SAPHO syndrome with cranial bone involvement, and review the previous literature on similar manifestations. It was revealed that SAPHO syndrome could lead to cranial bone involvement, which could involve the dura mater, leading to hypertrophic pachymeningitis, but the outcome is usually good. Janus kinase inhibitors may be a potential treatment option.

The Natural Sequence in Which Subclinical Inflamed Joint Tissues Subside or Progress to Rheumatoid Arthritis: A Study of Serial MRIs in the TREAT EARLIER Trial.

OBJECTIVE: The natural trajectory of clinical arthritis progression at the tissue level remains elusive. We hypothesized that subclinical inflammation in different joint tissues (synovitis, tenosynovitis, osteitis) increases in a distinct temporal order in patients with clinically suspect arthralgia (CSA) who develop rheumatoid arthritis (RA) and subsides in a different sequence when CSA spontaneously resolves. METHODS: We studied 185 serial magnetic resonance images (MRIs) from CSA patients with subclinical joint inflammation from the placebo arm of the TREAT EARLIER trial: 52 MRIs from 21 RA progressors (MRIs conducted at 1 year before, at 4 months before, and upon RA development), and 133 MRIs from 35 patients with spontaneous resolution of pain (MRIs conducted at baseline and at 4, 12, and 24 months). MRIs were scored for osteitis, synovitis, and tenosynovitis. We used cross-lagged models to evaluate 2 types of time patterns between pairs of inflamed tissues: a simultaneous pattern (coinciding changes) and a subsequent pattern (inflammatory changes in 1 tissue preceding changes in another tissue). RESULTS: In patients who developed RA, synovitis, tenosynovitis, and osteitis increased simultaneously. Increasing osteitis occurred in the final 4 months before RA diagnosis, following incremental tenosynovitis and synovitis changes during the 1 year to 4 months before diagnosis (P < 0.01). In anti-citrullinated protein antibody (ACPA)-positive and ACPA-negative patients who progressed to RA, osteitis increased just before RA development. In patients with pain resolution, simultaneous decreases in synovitis, tenosynovitis, and osteitis occurred, with tenosynovitis decreasing in the first 4 months after CSA onset preceding decreasing synovitis and osteitis during 4-12 months (P = 0.02 and P < 0.01). CONCLUSION: We identified natural sequences of subclinical inflammation in different joint tissues, which deepens our understanding of clinical arthritis and RA development. During RA progression, increasing osteitis followed previous increases in tenosynovitis and synovitis. During pain resolution, tenosynovitis decreased first, followed by decreasing synovitis and osteitis.

Radiation osteitis: incidence and clinical impact in the setting of radiation treatment for soft tissue sarcoma.

OBJECTIVE: Radiotherapy is an important component of soft tissue sarcoma management. Radiation osteitis is a common radiographic finding identified in the setting of radiotherapy on magnetic resonance imaging (MRI). This study aims to identify the incidence of radiation osteitis in patients who received radiotherapy for soft tissue sarcoma and if a further workup, including a biopsy, was performed for concerning MRI findings. MATERIALS AND METHODS: Medical records of patients with soft tissue sarcoma who received radiotherapy from 2008 to 2020 were retrospectively reviewed. Patients with at least one MRI of the sarcoma site following radiotherapy and information regarding radiotherapy treatments were included. MRIs of these patients were reviewed for the presence of radiation osteitis by two musculoskeletal radiologists. The clinical course of these patients including biopsy for concerning MRI findings, local recurrence, and metastasis was recorded. RESULTS: Thirty soft tissue sarcoma patients who received radiation for soft tissue sarcoma were included. Radiation osteitis was present in 18 patients. The time to osteitis present on MRI following radiotherapy completion was a median of 4.5 months. Biopsy for concerning MRI findings was performed in eight patients, five for local recurrence, and three for regional osseous metastasis. Three patients had confirmed osseous metastases. CONCLUSION: Although radiation osteitis is often a benign imaging finding, it can be difficult to discern these lesions from potentially malignant sites of disease. We recommend multidisciplinary management of soft tissue sarcoma at sarcoma centers to appropriately identify benign from malignant lesions and decide the necessity of a biopsy.

The promising role of DECT in the diagnosis of Osteitis Condensans Ilii: a case report.

Osteitis condensans ilii (OCI) is a noninflammatory condition of no clear etiology, cause of axial low back pain. It is characterized by sclerotic bone lesions at the iliac region of the sacroiliac joints. The diagnosis is based on radiological findings and the exclusion of other conditions associated with back pain. We present a case of bilateral OCI in a young woman with bone sclerosis at sacroiliac joints diagnosed with the use of Dual Energy CT.

[Groin pain in athletes-sportsmen's groin]. / Sportlerleiste ­ "Sportsmen's groin".

CLINICAL/METHODICAL ISSUE: Groin pain in athletes can have various causes. Radiologically, osteitis pubis and clefts with affection of the interpubic disc as well as muscle and tendon tears near the pubic bone can be clearly identified. STANDARD RADIOLOGICAL METHODS: Magnetic resonance imaging (MRI) is the imaging modality of choice, as well as single-leg stand imaging (flamingo view radiographs), and where appropriate symphysography. METHODICAL INNOVATIONS: Optimized MRI sequence protocol with oblique (axial oblique) slices parallel to the linea arcuata of the iliac bone is recommended. High-resolution MRI sequences and symphysography can detect superior and secondary cleft formation. Instabilities of the pubic symphysis can be diagnosed using flamingo view radiographs. PERFORMANCE: The MRI findings of osteitis pubis and clinical symptoms correlate. The presence of parasymphyseal bone marrow edema is the earliest morphological sign of acute osteitis pubis on MR imaging. Edema in the periosteal tissue and isolated muscle lesions next to the symphysis are generally associated with more severe clinical symptoms. ACHIEVEMENTS AND PRACTICAL RECOMMENDATIONS: Close communication between radiologists and the referring physicians is indispensable when planning an adequate imaging protocol, and precise knowledge of the clinical symptoms in the case of clinical suspicion of osteitis pubis allows for a reliable diagnosis and provides important prognostic information.

Performance of an MRI scoring system for inflammation of joints and entheses in peripheral SpA: post-hoc analysis of the CRESPA trial.

OBJECTIVES: The aim of this study was to investigate the reliability, validity, and sensitivity to change of a novel MRI scoring system in early peripheral SpA (pSpA). METHODS: MRI of the pelvis and lower extremities was performed before initiation of the TNF inhibitor golimumab in 56 patients and repeated in 46 patients who achieved sustained clinical remission after 24, 36 or 48 weeks. Three readers applied a semi-quantitative MRI scoring system for lower-extremity joint and entheseal inflammation. Four lesion types were assessed: entheseal osteitis, entheseal soft-tissue inflammation, joint osteitis, and joint synovitis/effusion. MRI response was defined as a decrease in MRI lower-extremity inflammation index (sum of scores from 75 sites, each scored 0-3) above the smallest detectable change (SDC). RESULTS: At follow-up, the MRI index decreased in 34 of 46 patients (74%), and 15 (33%) patients achieved MRI response, i.e. a decrease above SDC of 2.8. When restricting the analysis to patients with clinical involvement of lower-extremity sites that were assessed by MRI, 13 of 28 (46%) achieved MRI response. Interreader reliability was very good, with an average-measure intraclass correlation coefficient of 0.92 (95% CI: 0.85-0.95) for status scores and 0.89 (0.80-0.94) for change in scores. The MRI index correlated with other measures of disease activity, including CRP [Spearman's rho 0.41 (0.23-0.56)], swollen joint count of 6 joints [0.47 (0.27-0.63)], tender enthesis count of 14 entheses [0.32 (0.12-0.50)] and pain score [0.28 (0.08-0.46)], all P < 0.05. CONCLUSION: The proposed MRI lower-extremity inflammation index demonstrated reliability, validity, and sensitivity to change in patients with early pSpA. TRIAL REGISTRATION: Clinicaltrials.gov, http://clinicaltrials.gov, NCT01426815.

Idiopathic Osteosclerosis and Condensing Osteitis in a Sample of the Lebanese Population: A Digital Panoramic Based Study.

Background: Idiopathic osteosclerosis (IO) is an area of enlarged bone production in the jaw that usually appears radiopaque and round, elliptical, or irregular in shape. Condensing osteitis (CO) is a focalized osseous reaction leading to periapical sclerotic bone growth. Objective: The aim of this study was to investigate the prevalence, localization, shape, and dental relationship of IO and CO in a group of Lebanese patients and to correlate these findings to age and gender. Methods: 520 digital panoramic radiographs of patients (215 men and 305 women) ranging in age from 18 to 77 (mean age 40.89 years) who visited the Faculty of Dental Medicine, Lebanese University, for dental treatment were included in this study and assessed for IO and CO. The prevalence of the two lesions according to gender and age, as well as their localization, and dental relationship, were recorded and saved in an Excel sheet. Results: Among the 520 radiographs, 47 (9%) showed IO, and 30 (5.8%) showed CO. Both lesions are more frequent among females in their third decade and are essentially found in the mandible, mainly in relation to the root apices. Conclusion: Within the limits of this study, we concluded that in our sample of the Lebanese population, the prevalence of IO and CO is low and supports the theory that IO can be defined as developmental variations of normal bony architecture unrelated to a local stimulant, and CO could be considered reactive bone formations related to pulpitis, deep restoration, or caries.

Presence of axial spondyloarthritis associated sacroiliitis and structural changes on MR enterography: A direct comparison with sacroiliac joint MRI.

INTRODUCTION: To investigate the acute inflammatory and structural changes of sacroiliitis as auxiliary findings on magnetic resonance enterography (MRE) and their presence on closely timed conventional magnetic resonance imaging of the sacroiliac joint (SI joint MRI). MATERIALS AND METHODS: We screened axial spondyloarthritis patients for the simultaneous presence of MREs and SI joint MRIs. Two blinded radiologists evaluated SI joint MRIs and MREs on two separate occasions. We used the Assessment of SpondyloArthritis International Society (ASAS)/Outcome Measures in Rheumatology Network (OMERACT) definitions for SI joint MRI. We implemented previously published standard definitions for osteitis, erosion, sclerosis, and fatty infiltration of SI joint in MREs that contain T1w and T1w post-gadolinium sequences. RESULTS: SI joint MRI and MRE images were present in 43 patients. The median time between the two modalities was 14 (0-89) days. Twelve patients had ASAS-defined positive SI joint MRI. Radiologist-1 and radiologist-2 detected osteitis on MRE in nine and eight out of these 12 patients, respectively. The two radiologists detected ankylosis and fatty metaplasia with a complete agreement and sclerosis with an almost perfect agreement. Both radiologists agreed on erosions on SI joint MRI in the same 10 cases. Radiologists did not identify acute inflammatory or structural changes on MRE in patients with a negative SI joint MRI for these lesions. CONCLUSION: Along with intestinal findings, additional reporting of acute inflammatory and structural changes of the SI joint on a MRE is valuable and may alert physicians to the presence of previously not diagnosed axial spondyloarthritis.

Subchondral bone attenuation coefficient utility of the sacroiliac margins to differentiate spondyloarthritis and osteitis condensans ilii.

INTRODUCTION: Differentiating ankylosing spondylitis (AS) from osteitis condensans ilii (OCI) remains challenging for clinicians. The aim of this study was to determine whether Subchondral Bone Attenuation Coefficient of the SacroIliac margins (SBAC-SI) is different in AS, OCI and diffuse idiopathic skeletal hyperostosis (DISH). METHODS: A monocentric retrospective observational study was performed at the University Hospital of Besançon. Patients included were followed for AS, DISH or OCI and underwent CT scan including sacroiliac joint. Patients with tumour lesion of bone or a history of pelvic radiotherapy were excluded. AS and OCI patients were matched with a control of the same age and sex. SBAC-SI was evaluated by the sum of 24 identical circular regions of interest, 8 per slice (anterior, middle and posterior). RESULTS: Thirty AS and AS controls, 31 DISH, 29 OCI and OCI controls were included. SBAC-SI score was 9727 (±2430) in the OCI group (p<0.001), 3563 (±1860) in the AS group, 3899 (±1937) in the DISH group, 4224 (±1693) in the AS control group and 5445 (±1205) in the OCI control group. A threshold of 7500 HU had the best discriminative value between OCI and AS (youden index: 0.89). In AS, disease duration is negatively associated with SBAC-SI (r: -0.623; p<0.01) and HLA B27 is associated with lower SBAC-SI (6523 (5198; 7137) vs 2809 (1568; 3371); p<0.001). CONCLUSION: SBAC-SI is significatively different between AS and OCI and could help to distinguish these two diseases.

Athletic Osteitis Pubis Detected on 18 F-FDG PET/CT.

ABSTRACT: A 37-year-old male personal trainer presented with debilitating groin pains, fever, and night sweats. Enlarged inguinal lymph nodes were noticed during physical examination, and blood tests showed elevated erythrocyte sedimentation rate and C-reactive protein. 18 F-FDG PET/CT excluded lymphoma and other malignancy but showed intense FDG uptake at the pubic symphysis and cortical erosions of the pubic bones on CT. The patient was diagnosed with osteitis pubis, an inflammatory condition of the pubic symphysis commonly seen in athletes. Treatment with anti-inflammatory drugs was initiated. Within several weeks, pain decreased, and inflammatory markers normalized.