Diagnostics of Sacroiliitis According to ASAS Criteria: A Comparative Evaluation of Conventional Radiographs and MRI in Patients with a Clinical Suspicion of Spondyloarthropathy. Preliminary Results

Use of Multimodality Imaging in the Evaluation of Patients With Spondyloarthropathies and Sacroiliitis

Spondyloarthropathy (SpA) is one of the most common causes of low back pain. It is caused by inflammatory arthritis in the spine, manifesting in various forms such as psoriatic arthritis (PsA), ankylosing spondylitis (AS), and sacroiliitis. A comprehensive systematic literature search was done to evaluate and compare MRI, CT, single-photon emission CT, PET, ultrasound (US) imaging, low-dose CT, and diffusion-weighted imaging (DWI) techniques in assessing SpAs. The search strategy was constructed by an analysis of key terms from relevant articles in MEDLINE ProQuest, Embase, and PubMed. The key terms used to search for these articles were "SpA," "sacroiliitis," "spondylitis," "psoriatic arthritis," "MRI," "CT scan," "x-ray," "magnetic resonance imaging," "computed tomography," "bone density," and "ultrasound." A total of 1,131 articles published in English between January 1, 2003, and October 15, 2023 were identified and screened for eligibility by members of the research team, which resulted in 69 total articles selected for the final review. US has played an important role in visualizing joint inflammation and enthesitis (inflammation of the enthesis), which are common features of PsA. Although MRI and CT are considered more reliable modalities for diagnosing active sacroiliitis, US imaging with Doppler flow can also be useful in conjunction with CT images to visualize abnormal blood flow in the sacroiliac joints, as well as other joints affected by inflammatory arthritis. MRI provides increased diagnostic confidence in the diagnosis of sacroiliitis in active AS patients when compared to CT. CT is more sensitive than plain radiographs. The PET activity score showed a good correlation in diagnosing inflammatory sacroiliitis but lacked in identifying structural lesions. CT has high diagnostic accuracy, but it exposes patients to a high radiation dose. MRI visualizes joint and tissue inflammation, bone, and bone marrow change and can identify peripheral inflammation in soft tissue and joints in patients diagnosed with PsA. MRI can also visualize bone marrow changes and subchondral edema, which can aid in the early diagnosis of ankylosing SpA and gauge disease severity. DWI and short-tau inversion recovery imaging are both MRI techniques used in detecting sacroiliitis. MRI and CT are shown to be reliable imaging modalities for the diagnosis of sacroiliitis; however, it was found that Doppler US played an accurate role in the diagnosis as well. MRI visualizes joints and tissue with the most precision, making it useful in evaluating patients with PsA, while PET CT is useful in the diagnosis of inflammatory sacroiliitis patients. There is limited literature available comparing the multiple modalities of imaging available for each SpA. The review's objective is to analyze imaging findings in patients diagnosed with sacroiliitis and SpAs. The findings in this literature review are valuable for properly assessing and diagnosing patients suffering from SpAs.

Effect of Sacroiliac Joint Pain on Outcomes in Patients Undergoing Hip Arthroscopy for the Treatment of Femoroacetabular Impingement Syndrome: A Matched Comparative Cohort Analysis at Minimum 2-Year Follow-up

BACKGROUND

Patients with femoroacetabular impingement syndrome (FAIS) may frequently have co-existing sacroiliac joint (SIJ) pain. It is known that patients with lower back pain undergoing total hip arthroplasty (THA) have inferior outcomes; however, it is unclear what the effect of SIJ pain is on outcomes after hip arthroscopy.

PURPOSE

To determine whether patients undergoing hip arthroscopy with SIJ pain either subjectively or on physical examination achieve similar postoperative improvement in patient-reported outcomes (PROs) compared with patients without SIJ pain at 2-year follow-up.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients with a minimum 2-year follow-up who underwent primary hip arthroscopy for FAIS with SIJ pain were matched in a 1:2 ratio to controls without SIJ pain. Baseline demographics, as well as postoperative PROs and rates of achievement of the minimal clinically important difference (MCID) or Patient Acceptable Symptom State (PASS) at 2-year follow-up were compared between the 2 groups.

RESULTS

A total of 73 patients (75 hips) with SIJ pain were matched to 150 control patients (150 hips) without SIJ pain. Both groups demonstrated statistically significant improvement in all PROs at 2 years (P < .05 for all). Patients with SIJ pain had significantly lower postoperative PRO scores for the Hip Outcome Score-Activities of Daily Living (HOS-ADL) (SIJ pain: 80.4 ± 22.4 vs no SIJ pain: 88.0 ± 15.1; P = .006), modified Harris Hip Score (mHHS) (SIJ pain: 73.2 ± 22.8 vs no SIJ pain: 80.0 ± 17.3; P < .001), and International Hip Outcome Tool-12 questionnaire (iHOT-12) (SIJ pain: 61.7 ± 25.9 vs no SIJ pain: 73.7 ± 23.7; P = .008). There were no statistically significant differences in improvement (delta) in PRO scores between the 2 groups (P > .05 for all). The SIJ pain group had significantly lower achievement of MCID for the HOS-ADL (SIJ pain: 65.2% vs no SIJ pain: 80.5%; P = .044) but not HOS-SS, mHHS, or iHOT-12 (P > .05 for all). The SIJ pain group had significantly lower achievement of PASS for the mHHS (SIJ pain: 27.5% vs no SIJ pain: 45.3%; P = .030) and iHOT-12 (SIJ pain: 31.0% vs no SIJ pain: 56.0%; P = .010) but not the HOS-ADL and HOS-SS (P > .05 for both). Only 4.1% of patients with SIJ pain and 2.4% of controls required revision surgery or converted to THA at the time of final follow-up (P = .69).

CONCLUSION

Patients with FAIS and SIJ pain on history or physical examination experience significant improvement in PROs at 2 years after hip arthroscopy. However, they may be less likely to achieve the MCID or PASS and have significantly lower postoperative PROs compared with a matched cohort of patients without SIJ pain. Overall rates of revision and conversion to THA were similarly low in both groups.

Comparison between radiography and magnetic resonance imaging for the detection of sacroiliitis in the initial diagnosis of axial spondyloarthritis: a cost-effectiveness study

OBJECTIVE

The purpose of our study was to determine the cost-effectiveness of radiography and MRI-based imaging strategies for the initial diagnosis of sacroiliitis in a hypothetical population with suspected axial spondyloarthritis.

MATERIALS AND METHODS

A decision analytic model from the health care system perspective for patients with inflammatory back pain suggestive of axial spondyloarthritis was used to evaluate the incremental cost-effectiveness of 3 imaging strategies for the sacroiliac joints over a 3-year horizon: radiography, MRI, and radiography followed by MRI. Comprehensive literature search and expert opinion provided input data on cost, probability, and utility estimates. The primary effectiveness outcome was quality-adjusted life-years (QALYs), with a willingness-to-pay threshold set to $100,000/QALY gained (2018 American dollars).

RESULTS

Radiography was the least costly strategy ($46,220). Radiography followed by MRI was the most effective strategy over a 3-year course (2.64 QALYs). Radiography was the most cost-effective strategy. MRI-based and radiography followed by MRI-based strategies were not found to be cost-effective imaging options for this patient population. Radiography remained the most cost-effective strategy over all willingness-to-pay thresholds up to $100,000.

CONCLUSION

Radiography is the most cost-effective imaging strategy for the initial diagnosis of sacroiliitis in patients with inflammatory back pain suspicious for axial spondyloarthritis.

[Difficulties in diagnosing sacroiliitis in young patients]

In real clinical practice, back pain in young patients is associated with neurological manifestations of degenerative changes in the lumbosacral spine. However, such complaints may be a manifestation of a lesion of the sacroiliac joint-sacroiliitis, and degenerative changes in the spine may accompany it, but not cause pain. Sacroiliitis is an inflammatory lesion of the sacroiliac joint, which can develop as an independent disease or as a symptom of another nosology. The causes of this pathology are diverse: injuries, long-term overloading of the joint, congenital abnormalities of the joints, infectious or systemic diseases, and tumors. In neurological practice, sacroiliitis is similar to myofascial syndromes and can disguise as degenerative diseases of the spine, so early diagnosis and proper therapy are of particular importance. Awareness of doctors about the features of examination of young patients, the use of neuroimaging techniques (CT, MRI), laboratory diagnostics, will help to improve the results of therapy. Prescription of NSAIDs with a pronounced anti-inflammatory potential will slow down the progression of the inflammatory process.

Targeting inflammatory pathways in axial spondyloarthritis

The triggers and pathogenesis of axial spondyloarthritis (axSpA) are not yet completely understood. However, therapeutic agents targeting tumor necrosis factor-α and interleukin-17 inflammatory pathways have proven successful in suppressing many of the clinical symptoms and signs of axSpA, giving us an indication of which pathways are responsible for initiating and maintaining the inflammation. The mechanisms that eventuate in syndesmophytes and ankyloses are less clear. This review addresses these two critical pathways of inflammation, discussing their nature and these factors that may activate or enhance the pathways in patients with axSpA. In addition, genetic and other markers important to the inflammatory pathways implicated in axSpA are explored, and prognostic biomarkers are discussed. Treatment options available for the management of axSpA and their associated targets are highlighted.

Diagnostic imaging characteristics of canine infectious sacroiliitis

Infectious sacroiliitis has not been described in dogs. This retrospective case series describes the presentation, diagnostic imaging characteristics, and outcomes of 2 canine patients with infectious sacroiliitis. Selection criteria included presentation with back pain from 2010 to 2017, diagnostic imaging of the sacroiliac joints, and short- and long-term response to antibiotic therapy. Medical records, and magnetic resonance imaging (MRI) were reviewed by a Board-certified veterinary radiologist, a neurologist, and a small animal intern. Two dogs met the inclusion criteria. Magnetic resonance imaging revealed unilaterally wide and irregular sacroiliac joint spaces, with juxta-articular soft tissue contrast enhancement and bone marrow edema. One patient had a communicating abscess of the psoas muscle, which cultured positive for Pasteurella canis. Following treatment with pain relief medications and antibiotics, both patients made a complete clinical recovery, with no signs of lameness 2 to 4 weeks after cessation of treatment, and no lameness reported by the owner afterwards. Infectious sacroiliitis should be considered when dogs are presented with lumbosacral pain.

Association between inflammatory back pain features, acute and structural sacroiliitis on MRI, and the diagnosis of spondyloarthritis

OBJECTIVES

To evaluate the association between inflammatory back pain (IBP) features, acute and structural MRI findings suggestive of sacroiliitis, and diagnosis of spondyloarthritis (SpA).

METHODS

Data from 224 patients who underwent MRI for suspected sacroiliitis (2005-2015) was retrospectively reviewed by an expert rheumatologist for the presence of IBP features and for clinical standard of reference diagnosis. A telephone questionnaire was performed in cases of missing data. Acute and structural MRI parameters were scored by an experienced radiologist for the presence of sacroiliitis using the Assessment of Spondyloarthritis International Society (ASAS) criteria, Berlin score, and observer's global impression (GI) scores. Association between IBP features and MRI scores, and odds ratio for SpA diagnosis, were calculated.

RESULTS

One hundred ninety-three subjects were included (119 F:74 M, mean age 39.7 ± 15.6, mean follow-up 49 ± 18 months). Fifty-two (26.9%) subjects were diagnosed with SpA. IBP scores were significantly higher in SpA patients (p < 0.001). IBP, ASAS, and GI MRI scores were significantly associated with the SpA diagnosis (p < 0.001 for all). The presence of night pain and morning stiffness was significantly associated with sacroiliac-joints' bone marrow edema (BME, p < 0.05). Sensitivity for diagnosis of SpA was high for IBP (96%) and low for the MRI parameters (26.9-57.4%), and specificity was low for IBP (32%) and high for the MRI parameters (88.3-94.3%).

CONCLUSIONS

The presence of IBP features is highly associated with diagnosis of SpA and correlates with MRI BME, all probably reflect inflammation. The combination of IBP and MRI should be the cornerstone in the clinician's final diagnosis of SpA.

Whole-lesion ADC histogram analysis and the spondyloarthritis research consortium of canada (SPARCC) MRI index in evaluating the disease activity of ankylosing spondylitis

BACKGROUND

Conventional MRI is limited in quantitative evaluation of ankylosing spondylitis (AS) activity states. A comparison of the effectiveness of the whole-lesion apparent diffusion coefficient (ADC) histogram analysis with the Spondyloarthritis Research Consortium of Canada (SPARCC) MRI index in evaluating the disease activity of AS might aid in this assessment.

PURPOSE

To compare the effectiveness of the whole-lesion ADC histogram analysis with the SPARCC MRI index in evaluating the disease activity states of AS.

STUDY TYPE

Prospective.

POPULATION

A total of 57 AS patients and 27 healthy matched volunteers were included.

FIELD STRENGTH/SEQUENCE

3.0T MR including a diffusion-weighted imaging (DWI) sequence (b = 0, 1000 s/mm² ).

STATISTICAL TESTS

One-way analysis of variance (ANOVA) and Scheffe's post-hoc was used to compare the parameters among different groups. A receiver operating characteristic (ROC) analysis and the Spearman rank correlation were performed to test the diagnostic performance of all parameters in distinguishing different disease activity states and determining the correlations between them.

ASSESSMENT

AS disease activity states was evaluated according to the Ankylosing Spondylitis Disease Activity Score (ASDAS). Initial DWI images and corresponding ADC maps were imported into our in-house software. Regions of interest (ROIs) were drawn in all slices and the relevant parameters were derived simultaneously. The SPARCC MRI index scores were counted artificially based on T₂ -PDW-SPAIR images.

RESULTS

The ADC_mean , ADC percentiles, and SPARCC MRI index of the active group were significantly higher than the inactive and control groups (all P < 0.001). The 90th percentile could differentiate the inactive from the control group and the low disease activity group from the inactive group (P = 0.011 and 0.006, respectively). The 50th percentile of the high disease activity group was significantly higher than the low group (P = 0.004), while the SPARCC MRI index of the very high disease activity group was higher than the high group (P < 0.001).

DATA CONCLUSION

The whole-volume ADC histogram analysis was superior to the SPARCC MRI index in assessing AS activity states.

LEVEL OF EVIDENCE

1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;50:114-126.

Classification Terminology and Definitions in Reporting of MRI in Axial Spondyloarthritis

Spondyloarthritis (SpA) is a group of chronic inflammatory conditions which severely impact quality of life. Several criteria have been developed in the past to aid the diagnosis of SpA based on symptoms and radiographic changes during the course of the disease. However, it takes several years before structural changes manifest on conventional radiographs, leading to a diagnostic delay of 6 to 10 years. The use of MRI and its incorporation into the Assessment of Spondyloarthritis (ASAS) criteria, has radically changed the diagnosis of SpA in the last decade by allowing visualisation of both active and chronic inflammatory changes and enabling clinicians to recognise SpA during it’s early stage and initiate treatment. An understanding of the various terminology used in the divisions of disease presentations and their relevant imaging findings are key, along with the use of clear definitions of structural and inflammatory changes on MRI, in ensuring accurate diagnosis and classification of SpA.

Ankylosing Spondylitis: A Review

Ankylosing spondylitis is a chronic autoimmune inflammatory condition belonging to the spondyloarthropathy category of rheumatic diseases. It typically affects the axial skeleton but may also present with peripheral arthritis and extra-articular features. Ankylosing spondylitis tends to occur in patients under the age of 45 years, has a higher incidence in males, and can lead to disability and reduced quality of life if not adequately treated. Management consists of a multidisciplinary team approach. Although traditional disease modifying anti-rheumatic drugs are less effective for the axial component of this disease, biologic therapies do seem effective. In severe cases, surgery may be warranted.

Imaging of juvenile spondyloarthritis. Part II: Ultrasonography and magnetic resonance imaging

Juvenile spondyloarthropathies are mainly manifested by symptoms of peripheral arthritis and enthesitis. Early involvement of sacroiliac joints and spine is exceptionally rare in children; this usually happens in adulthood. Conventional radiographs visualize late inflammatory lesions. Early diagnosis is possible with the use of ultrasonography and magnetic resonance imaging. The first part of the article presented classifications and radiographic presentation of juvenile spondyloarthropathies. This part discusses changes seen on ultrasonography and magnetic resonance imaging. In patients with juvenile spondyloarthropathies, these examinations are conducted to diagnose inflammatory lesions in peripheral joints, tendon sheaths, tendons and bursae. Moreover, magnetic resonance also shows subchondral bone marrow edema, which is considered an early sign of inflammation. Ultrasonography and magnetic resonance imaging do not show specific lesions for any rheumatic disease. Nevertheless, they are conducted for early diagnosis, treatment monitoring and identifying complications. This article presents a spectrum of inflammatory changes and discusses the diagnostic value of ultrasonography and magnetic resonance imaging.

Selected issues in diagnostic imaging of spondyloarthritides: psoriatic arthritis and juvenile spondyloarthritis

Spondyloarthritides (also known as spondyloarthropathies) are a group of rheumatic diseases that consists of diversified entities, i.e. ankylosing spondylitis, reactive arthritis, psoriatic arthritis, arthritis in the course of Crohn's disease and ulcerative colitis, and juvenile spondyloarthropathies. In the diagnostics of spondyloarthritides, plain radiography has played a crucial role for years due to its undisputed ability to show distinctive bony changes. Yet as those diseases often manifest themselves by soft tissue pathology and bone marrow inflammation, ultrasonography and magnetic resonance imaging are currently a subject of numerous studies in the quest for setting up diagnostic criteria, especially at early stages of inflammatory processes. In our review, we present an up-to-date insight into classifications, etiopathogenesis and imaging of psoriatic arthritis and juvenile spondyloarthritis.

Spectrum of Inflammatory Changes in the SIJs on Radiographs and MR Images in Patients with Suspected Axial Spondyloarthritis

BACKGROUND

The aim of the paper was to compare radiographs and MRI in assessment of active and chronic inflammatory changes in the sacroiliac joints in patients with chronic back pain and suspected axial spondyloarthritis. Moreover, the aim was to determine which of the two methods is more accurate in diagnosing individual inflammatory changes in the sacroiliac joints and whether there is a correlation between radiographs and MRI in their identification.

MATERIAL/METHODS

The analysis was conducted in a group of 101 patients, including 61 women and 40 men, referred to radiographs and MR examinations by rheumatologists due to chronic back pain. AP images of the lumbar region of the spine were performed in each patient in the supine position. The images included the sacroiliac joints. Changes in the SIJs were assessed based on the New York criteria of 1966. In MR examination, the SIJs were assessed in terms of the presence of active and chronic inflammatory changes described by the ASAS. The statistical analysis of the variables tested was conducted in the Excel and Statistica systems.

RESULTS

In relation to the final clinical diagnosis of axSpA, MRI had higher sensitivity and specificity than radiography in diagnosing sacroiliitis (sensitivity: 71% vs. 22%, specificity: 90% vs. 94% on radiographs according to New York criteria. In relation to MRI, radiographs resulted in 40% of incorrect sacroiliitis diagnoses (both false positive and false negative results). In as many as 50% of cases (7/14), MRI failed to confirm the presence of inflammatory changes in the sacroiliac joints observed in radiography according to the modNY criteria (false positive results on radiographs). Both examinations are characterised by very low agreement, which is near to random, in assessing individual features of sacroiliitis, such as sclerosis, change in the joint space width, erosions and ankylosis.

CONCLUSIONS

1. Radiographs do not allow early inflammatory lesions indicating sacroiliitis to be diagnosed, which leads to diagnostic delay. MRI is the method of choice in diagnosing early sacroiliitis and detecting structural lesions, in particular sclerosis and erosions. 2. Radiographs and MRI are characterised by low, near to random, agreement in the detectability of the individual inflammatory changes in the sacroiliac joints.

Frequency of sacroiliitis among patients with low back pain

Introduction

Sacroiliitis is one of the important symptoms in patients attending infectious diseases and rheumatology clinics. Some patients with sacroiliitis are asymptomatic, and some have unspecific symptoms. The aim of this study was to determine the frequency of sacroiliitis causes among patients attending Shahid Sadoughi’s infectious disease and rheumatology clinics.

Methods

In this study, we evaluated patients attending Shahid Sadoughi rheumatology and infectious diseases clinic in 2014. Patients who had positive findings in favor of sacroiliitis were evaluated by history, physical exam, laboratory tests, and imaging. The patients were divided into infectious, inflammatory non-infectious, and degenerative causes. The data were analyzed by IBM SPSS version 20 using the independent samples t-test, ANOVA, the chi-squared test, and the Fisher’s exact test.

Results

We studied 136 patients. Among them 64 (47.1%) were male, and 72 (52.9%) were female. The mean age of the participants was 34.28 ± 10.36 years. Among the patients, 12 (8.8%) had infectious causes, 120 (88.2%) had inflammatory non-infectious causes, and four (2.9%) had degenerative causes.

Conclusion

Based on our results, inflammatory non-infectious causes are at the top of the list of sacroiliitis causes, but we should always consider infectious causes, including brucellosis.