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.

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.

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.

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.

Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome of femoral neoplasm-like onset: a case-based review.

Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome is an umbrella term covering a constellation of bone lesions and skin manifestations, but has rarely been clarified in the clinic. We report a 28-year-old woman who had initial onset of SAPHO syndrome with involvement of the femur, and she experienced a tortuous diagnostic course. We also performed a literature review of SAPHO syndrome cases involving the femur and summarize several empirical conclusions by integrating previous findings with our case. Furthermore, we propose our perspective that ailment of the skin caused by infection of pathogens might be the first hit for triggering or perpetuating the activation of the immune system. As a result, musculoskeletal manifestations are probably the second hit by crosstalk of an autoimmune reaction. The skin manifestations preceding bone lesions can be well explained. Current interventions for SAPHO syndrome remain controversial, but drugs aiming at symptom relief could serve as the first preference for treatment. An accurate diagnosis and appropriate treatment can cure patients in a timely manner. Although the pathogenesis of SAPHO syndrome remains to be determined, physicians and surgeons still need to heighten awareness of this entity to avoid invasive procedures, such as frequent biopsies or nonessential ostectomy.

Foot shape and radiographs of free-ranging Nubian giraffe in Uganda.

Foot health in zoo giraffe has been a topic of recent research, although little is known about the foot health of free-ranging giraffe. This study describes the foot shape and radiographic pathological changes in 27 young adult Nubian giraffe (Giraffa camelopardalis camelopardalis) from a translocation in Uganda (August 2017). Giraffe feet were observed to have a concave sole, the hoof wall was longest by the toe tip, and the weight-bearing surface of the foot was primarily along the periphery of the foot including hoof wall, parts of the heel, and the edge of the sole. Radiographs showed that pedal osteitis and sesamoid bone cysts were relatively uncommon (3/24 giraffe with osteitis, 1/24 giraffe with sesamoid cysts), and that no giraffe in the study had P3 joint osteoarthritis, P3 rotation, or P3 fractures. Radiographs consistently demonstrated a positive palmar/plantar angle with the sole of the hoof thicker at the heel than by the toe tip, with the non weight-bearing palmar/plantar angle measuring 1.6°- 4.3°. This is the first systematic review of foot shape and radiographs in free-ranging giraffe and demonstrates a low prevalence of foot pathologies. This study suggests qualitative differences in foot shape, foot health, radiographic anatomy, and foot pathologies when comparing free-ranging and zoo giraffe. Further research is needed to identify why these differences occur and whether husbandry modifications could help improve zoo giraffe foot health and prevent associated lameness.

Clinical characteristics and treatment status of pustulotic arthro-osteitis: A single-center study involving 51 cases.

Pustulotic arthro-osteitis (PAO) is a major complication of palmoplantar pustulosis (PPP). In orthopedic surgery outpatient clinics, PPP patients with osteoarticular symptoms are seen frequently, but PAO's clinical features remain not well known. To determine Japanese patients' clinical features and treatment status with PAO, we conducted a single-center retrospective epidemiologic survey. Clinical features, including gender, age, smoking habit, the onset pattern, interval between skin manifestation and osteoarticular symptoms, and the incidence of sternoclavicular joint lesions, axial and peripheral joint lesions, were examined. The association between physical status and image findings by X-ray, computed tomography, bone scintigraphy with Technetium99 , or magnetic resonance imaging was evaluated. The distribution pattern of peripheral joint lesions and the treatment status were evaluated. We identified 51 patients, 10 men and 41 women, with PAO. The average age was 48 years and 59% were smokers. The frequency of onset patterns was skin-leading type (63%), simultaneous onset (18%), and osteoarticular leading type (16%). The average interval between skin involvement and osteoarticular involvement in skin-leading type was significantly longer than that in osteoarticular leading type (7.1 years vs. 2.0 years). A sternoclavicular joint (SCJ) lesion was detected in 65% cases, and the physical findings of SCJ were significantly related to the image findings. Axial and peripheral joint lesions were detected in the same ratio (23 cases, 45%). In the peripheral joints, the finger joint was the most common (26%), followed by the shoulder joint (21%). Patients were treated with nonsteroidal anti-inflammatory drugs (76%), followed by conventional synthetic disease-modifying antirheumatic drugs (DMARDs) (29%) and biological DMARDs (9.8%). Tonsillectomy was performed in 11 cases. In conclusion, PAO more frequently involves SCJ in middle-aged women who smoke. Given that osteoarticular leading type was detected in 16% cases, seronegative oligoarthritis patients should be monitored for PPP, leading to a diagnosis of PAO.

Radical versus Functional Endoscopic Sinus Surgery for Osteitis in Chronic Rhinosinusitis.

INTRODUCTION: Osteitis in chronic rhinosinusitis (CRS) is a predictive factor of disease severity and an important potential reason for disease recalcitrance. Other than medical treatment, transnasal endoscopic surgery could be another choice to deal with osteitis in CRS. OBJECTIVE: In this study, 2 different surgical outcomes and influence in patients with osteitis in CRS were discussed. METHODS: A retrospective analysis of 51 cases was carried out. Osteitis in CRS was confirmed by sinus computed tomography (CT). According to surgical management, patients were divided into the radical endoscopic sinus surgery (RESS) group (n = 24) and functional endoscopic sinus surgery (FESS) group (n = 27). Baseline measures and postoperative outcomes were evaluated by symptom visual analog scale (VAS), peripheral blood eosinophil percentage, serum total IgE, skin prick test, endoscopy Lund-Kennedy score, CT scan Lund-Mackay score, and global osteitis scoring scale (GOSS) in 2 groups. RESULTS AND CONCLUSIONS: There was no significant difference between the 2 groups in age, gender, and complicated with allergic rhinitis and asthma. The preoperative symptom VAS score and endoscopy Lund-Kennedy score were higher in the RESS group than in the FESS group, and the Lund-Mackay score and GOSS score were similar in the 2 groups. One year after surgery, symptom VAS scores, endoscopy Lund-Kennedy score, and Lund-Mackay score were significantly lower in the 2 groups. The endoscopy Lund-Kennedy score and Lund-Mackay score were lower in the RESS group than in the FESS group 1 year after surgery. RESS was more effective in reducing inflammatory load of sinuses in patients with osteitis in CRS.

18F-Sodium Fluoride PET/CT Findings in Osteitis Condensans Ilii.

ABSTRACT: Osteitis condensans ilii (OCI) is a benign cause of low back pain for which no clear etiology has been identified. We report cases of 2 women with breast cancer referred for 18F-NaF PET/CT for skeletal staging. Both cases show characteristic findings of OCI on CT images, with 18F-NaF PET uptake in symptomatic patient and no uptake in asymptomatic. 18F-NaF PET CT can be useful in evaluating back pain and may be used as an adjunctive biological maker for assessing OCI as a potential cause of pain.

Impact of Paranasal Sinus Surgery in Granulomatosis With Polyangiitis: A Longitudinal Computed Tomography Study.

OBJECTIVES/HYPOTHESIS: Severe chronic rhinosinusitis (CRS) in patients with granulomatosis with polyangiitis (GPA) failing medical therapies can be treated with paranasal sinus surgery. Whether this surgery protects from progressive sinonasal damage remains unknown. Here, we aimed to analyze time-dependent relations between sinus surgeries and computed tomography (CT) imaging features in the CRS of GPA. STUDY DESIGN: Longitudinal observational study. METHODS: We assessed CRS features including bone thickening by global osteitis scoring scale, bone erosions, and mucosal thickening by Lund-Mackay scores in serial paranasal sinus CT scans (742 CT scans in total) from a cohort of 127 well-characterized GPA patients. Data on sinonasal surgical procedures were from a mandatory national registry and from chart review. We defined the time from baseline CT to last CT as the study observation period in each patient. Datasets were analyzed by linear mixed models. RESULTS: We found that 23/127 cohort patients had one or more paranasal sinus surgical procedures, and 96% of these (22/23) had osteitis by CT after surgery. In patients with nasal surgery alone or no surgery, we identified osteitis in 7/11 (64%) and 45/93 (48%), respectively. During the observation period of a median of 5 years, 38 patients had progression of their sinus osteitis, with the highest annual osteitis progression rates observed around the time of surgery. CONCLUSIONS: In this cohort, paranasal sinus surgery was associated with prevalence, severity, and progression rate of sinus osteitis, indicating that sinus surgery does not reduce the bone damage development in the CRS of GPA. LEVEL OF EVIDENCE: 4 Laryngoscope, 130: E460-E468, 2020.

Crizotinib-induced osteitis mimicking bone metastasis in a stage IV ALK-rearranged NSCLC patient: a case report.

BACKGROUND: Targeted therapies are a standard of care for first-line treatment of Anaplastic lymphoma kinase (ALK)-rearranged non small cell lung cancer (NSCLC). Giving the rapid pace of drug discovery and development in this area, reporting of adverse effects of ALK inhibitors is crucial. Here, we report a case of osteitis induced by an ALK inhibitor mimicking bone metastasis, a previously undescribed side effect of crizotinib. CASE PRESENTATION: A 31-year-old woman with stage IV ALK-rearranged NSCLC presented with back pain after 3 months of crizotinib treatment. Diagnostic work-up showed osteitis on the 4th and 5th thoracic vertebrae, anterior soft tissue infiltration and epiduritis, without any sign of infection. Spinal cord decompression, histological removal and osteosynthesis were performed. Histologic examination showed necrosis with abundant peripheral neutrophils, no microorganism nor malignant cell. Symptoms and Computarized Tomography-abnormalities rapidly diseappeared after crizotinib withdrawal and did not recur after ceritinib onset. CONCLUSIONS: This is the first report of crizotinib-induced osteitis. Crizotinib differs from other ALK inhibitors as it targets other kinases as well, which may have been responsible for the osteitis. Crizotinib can induce rapidly extensive osteitis, which can mimic tumor progression.