Blurring and Irregularity of the Subchondral Cortex in Pediatric Sacroiliac Joints on T1 Images: Incidence of Normal Findings That Can Mimic Erosions

OBJECTIVE

To determine prevalence of variations of subchondral bone appearance that may mimic erosions on T1-weighted magnetic resonance imaging (MRI) of pediatric sacroiliac (SI) joints according to age and sex.

METHODS

With ethics committee approval and informed consent, SI joint MRIs of 251 children (132 girls), mean age 12.4 years (range 6.1-18.0 years), were obtained in 2 cohorts: 127 children imaged for nonrheumatic reasons, and 124 children with low back pain but no features of sacroiliitis at initial clinical MRI review. MRIs were reviewed by 3 experienced radiologists, blinded from each other, for 3 features of the cortical black line representing the subchondral bone plate on T1-weighted MRI: visibility, blurring, and irregularity.

RESULTS

Based on agreement from 2 or more readers, the cortical black line was partially absent in 88.4% of the children, blurred in 34.7%, and irregular in 41.4%. All these features were most common on the iliac side of SI joints and at the first sacral vertebra level. Clearly visualized, sharply delineated SI joints with none of these features were seen in only 8.0% of children, or in 35.1% if we conservatively required agreement of all 3 readers to consider a feature present. There was no significant difference between sexes or cohorts; findings were similar across pediatric age groups.

CONCLUSION

Understanding the normal MRI appearance of the developing SI joint is necessary to distinguish physiologic findings from disease. At least two-thirds (65%) of normal pediatric SI joints showed at least 1 feature that is a component of the adult definition of SI joint erosions, risking overdiagnosis of sacroiliitis.

Magnetic resonance imaging findings in the normal pediatric sacroiliac joint space that can simulate disease

BACKGROUND

Magnetic resonance imaging (MRI) features of active sacroiliac joint inflammation include joint space fluid and enhancement, but it is unclear to what extent these are present in normal children.

OBJECTIVE

To describe normal MRI appearances of pediatric sacroiliac joint spaces in boys and girls of varying ages.

MATERIALS AND METHODS

In this ethics-approved prospective study, 251 children (119 boys, 132 girls; mean age: 12.4 years, range: 6.1-18.0 years), had both oblique-coronal T1-weighted and short tau inversion recovery (STIR) sacroiliac joint MRI. Of these, 127 were imaged for other reasons and had asymptomatic sacroiliac joints ("normal cohort") while 124 had low back pain with no features of sacroiliitis on initial clinical MRI review ("low-back-pain cohort"). Post-gadolinium T1-weighted sequences were available in 16/127 normal and 124/124 low-back-pain subjects. Three experienced radiologists scored high signal in the sacroiliac joint space on STIR (score 0=absent; 1=high signal compared to normal bone marrow present anywhere in the joint but not as bright as fluid [compared to vessels, cerebrospinal fluid]; 2=definite fluid signal in part of the joint; 3=definite fluid signal, entire vertical height, majority of slices) and, when available, joint space post-contrast enhancement (0=no high signal/enhancement; 1=thin, symmetrical, mildly increased linear high signal present in the joint space; 2=focal, thick or intense enhancement). Associations between joint signal scores, age, gender and sacral apophyseal closure were analysed.

RESULTS

Increased signal on STIR (score 1-3) was present in 74.7% of pediatric sacroiliac joint spaces, as intense as fluid in 18.4%. There was no significant difference in proportion by gender, side or cohort, but girls showed peak signal earlier than boys (10 years old vs. 12 years old, respectively). On post-gadolinium T1-weighted sequences, a thin rim of increased signal was nearly universally seen in sacroiliac joint spaces without focal, intense or thick post-contrast enhancement.

CONCLUSION

Sacroiliac joint spaces of most children demonstrate mildly increased signal on STIR, compared to normal bone marrow, and thin rim-like enhancement on post-contrast T1 images, likely related to cartilage. These findings should not be confused with sacroiliitis.

Low-dose computed tomography for axial spondyloarthritis: update on use and limitations

PURPOSE OF REVIEW

Recent developments in low-dose computed tomography (ldCT) have greatly reduced radiation exposure levels. This article reviews what a ldCT is and its use and limitations for imaging axial spondyloarthritis.

RECENT FINDINGS

Detection of structural damage in bone with CT is far superior to radiography and ldCT of the sacroiliac joints (SIJ) can now be done at radiation exposure levels equivalent to, or even less than, conventional radiography. ldCT should be considered a 'first-choice' test for arthritis imaging, and wherever available, SIJ ldCT may completely replace conventional radiography. Radiation exposure in the spine with ldCT is lower than conventional CT. However, it is unclear whether the additional information regarding structural damage changes in the spine provided by ldCT will alter patient management sufficiently often to merit switching from spinal radiography to ldCT in routine clinical practice. In addition, ldCT cannot assess osteitis disease activity for which MRI remains the best test.

SUMMARY

ldCT of the sacroiliac joints (SIJ) can be done at radiation exposure levels equivalent to, or less than, radiography and ldCT may completely replace SIJ radiography. However, the role of spinal ldCT for spondyloarthritis is not clear and MRI is far superior for detecting disease activity.

Development of a technique for MRI gold-standard direct volumetric measurement of complex joint effusion, and validation at the hip

OBJECTIVE

Accurate joint fluid quantification on MRI cannot simply rely on measuring the maximum fluid depth or using an ellipsoid approximation as this does not fully characterize the complex shape of a fluid-filled joint. As per the Outcome Measurement in Rheumatology (OMERACT) filter, we sought to evaluate the feasibility, reliability, and validity of a semi-automated supervised technique to quantify hip effusion volume.

MATERIALS AND METHODS

Ninety-three hip osteoarthritis patients were imaged with coronal short TI inversion recovery (STIR) and sagittal intermediate weighted fat-suppressed (IWFS) sequences at two time points (Fig. 1). Volumetric quantitative measurement (VQM) of joint fluid and measurement of the largest femoral neck fluid thickness (FTM) was performed using the custom MATLAB software. Self-reported Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and clinical measures of pain, stiffness, and function were recorded.

RESULTS

Inter-observer reliability was significantly higher for VQM than FTM (ICC = 0.96 vs. 0.85, p < 0.05). VQM and FTM correlated moderately (r = 0.76, p < 0.0001). There was significantly more articular fluid in symptomatic than asymptomatic hips at baseline (mean = 9.8 vs. 5.9 mL). Volumetric quantitative measurement generally displayed more frequent and stronger correlations to clinical parameters than FTM. Volumetric quantitative measurement required 3.9 min/hip vs. < 1 min/hip for femoral neck fluid thickness.

CONCLUSION

Volumetric quantitative measurement of joint effusion can serve as an MRI gold-standard, could apply to other joints and collections, and is highly suited to future automation.

Volumetric quantitative measurement of hip effusions by manual versus automated artificial intelligence techniques: An OMERACT preliminary validation study

OBJECTIVE

Preliminary assessment, via OMERACT filter, of manual and automated MRI hip effusion Volumetric Quantitative Measurement (VQM).

METHODS

For 358 hips (93 osteoarthritis subjects, bilateral, 2 time points), 2 radiologists performed manual VQM using custom Matlab software. A Mask R-CNN artificial-intelligence (AI) tool was trained to automatically compute joint fluid volumes.

RESULTS

Manual VQM had excellent inter-observer reliability (ICC 0.96). AI predicted hip fluid volumes with ICC 0.86 (status), 0.58 (change) vs. 2 human readers.

CONCLUSION

Hip joint fluid volumes are reliably assessed by VQM. It is feasible to automate this approach using AI, with promising initial reliability.

Central reader evaluation of MRI scans of the sacroiliac joints from the ASAS classification cohort: discrepancies with local readers and impact on the performance of the ASAS criteria

OBJECTIVES

The Assessment of SpondyloArthritis international Society (ASAS) MRI working group conducted a multireader exercise on MRI scans from the ASAS classification cohort to assess the spectrum and evolution of lesions in the sacroiliac joint and impact of discrepancies with local readers on numbers of patients classified as axial spondyloarthritis (axSpA).

METHODS

Seven readers assessed baseline scans from 278 cases and 8 readers assessed baseline and follow-up scans from 107 cases. Agreement for detection of MRI lesions between central and local readers was assessed descriptively and by the kappa statistic. We calculated the number of patients classified as axSpA by the ASAS criteria after replacing local detection of active lesions by central readers and replacing local reader radiographic sacroiliitis by central reader structural lesions on MRI.

RESULTS

Structural lesions, especially erosions, were as frequent as active lesions (≈40%), the majority of patients having both types of lesions. The ASAS definitions for active MRI lesion typical of axSpA and erosion were comparatively discriminatory between axSpA and non-axSpA. Local reader overcall for active MRI lesions was about 30% but this had a minor impact on the number of patients (6.4%) classified as axSpA. Substitution of radiography with MRI structural lesions also had little impact on classification status (1.4%).

CONCLUSION

Despite substantial discrepancy between central and local readers in interpretation of both types of MRI lesion, this had a minor impact on the numbers of patients classified as axSpA supporting the robustness of the ASAS criteria for differences in assessment of imaging.

Low back pain and radiographic severity as predictors in hip osteoarthritis patients receiving steroid injection therapy

INTRODUCTION

We investigated the effects of lower back pain (LBP) on measures of pain, disability, and function in highly symptomatic hip OA patients receiving intra-articular steroid injection (IASI) therapy. We also investigated the effect of radiographic severity of hip OA for comparison to LBP.

METHODS

97 consenting subjects with symptomatic hip OA presenting for IASI were evaluated at baseline, assessed over an 8-week period, and followed at least 1 year later for new arthroplasty. At baseline and 8 weeks follow-up patient demographics, presence/absence of back pain, physical function tests, a single anteroposterior pelvis x-ray, and subjective scores of pain, stiffness and function (VAS and WOMAC) were collected. We also followed which subjects proceeded to obtain total hip arthroplasty in the examined hip.

RESULTS

Cohorts with LBP reported significantly worse scores for all of VAS pain and WOMAC questionnaires but showed no difference in ROM and were not more likely to proceed to arthroplasty. Cohorts with severe radiographic OA had significantly worsened scores for stiffness (χ² = 6.74, p = 0.009), decreased ROM (p < 0.01), and were more likely to proceed to arthroplasty (χ² = 9.79, p = 0.044).

DISCUSSION

Back pain has a substantial effect on clinical parameters relevant to assessment of severity of hip OA, especially self-reported pain and function. This finding highlights LBP as a significant confounding factor in hip OA patient assessments and will inform future studies to determine the most effective treatment strategies for hip OA patients.

Canada-Denmark MRI scoring system of the spine in patients with axial spondyloarthritis: updated definitions, scoring rules and inter-reader reliability in a multiple reader setting

Objective

To validate the Canada-Denmark (CANDEN) MRI scoring system for the spine in axial spondyloarthritis with updated lesion definitions.

Methods

Lesion definitions in the CANDEN system were updated and illustrated by a consensus set of reference images. Sagittal spine MRIs of 40 patients with axial spondyloarthritis obtained at baseline and at week 52 after initiation of treatment with the tumour necrosis factor inhibitor golimumab were evaluated in unknown chronology by seven readers blinded to all other data.

Results

CANDEN MRI spine inflammation score had very good reliability for status scores (single-measure intraclass correlation coefficient (ICC) of 21 reader pairs median of 0.91 (IQR 0.88-0.92)) and change scores (ICC 0.88 (0.86-0.92)). CANDEN MRI spine fat score had good to very good reliability for status scores (ICC 0.79 (0.75-0.86)) and moderate to good reliability for detecting change (ICC 0.59 (0.46-0.73)). CANDEN MRI spine bone erosion score and CANDEN MRI spine new bone formation score had slight to moderate reliability for status scores (ICC 0.38 (0.32-0.52) and 0.39 (0.27-0.49), respectively).

Conclusion

The CANDEN MRI spine scoring system allows a comprehensive evaluation of inflammation, fat, bone erosion and new bone formation of the spine in patients with axial spondyloarthritis. It demonstrated very good reliability for detecting change in inflammation, moderate to good reliability for detecting change in fat, and slight to moderate reliability for detecting bone erosions and new bone formation. Studies with longer follow-up or patients with more advanced spinal involvement may be needed to reliably detect change in bone erosion and new bone formation scores.

Trial registration number

NCT02011386.

Can effusion-synovitis measured on ultrasound or MRI predict response to intra-articular steroid injection in hip osteoarthritis?

OBJECTIVES

Intra-articular steroid injection (IASI) is an effective therapy for hip osteoarthritis (OA), but carries risks and provides significant pain relief to only two thirds of patients. We attempted to predict response to IASI in hip OA patients using baseline clinical, ultrasound, and MRI data.

METHODS

Observational study of 97 subjects with symptomatic hip OA presenting for IASI. At baseline and 8 weeks we obtained hip MRI, grayscale and Doppler ultrasound, clinical range of motion (ROM), timed-up and go test (TUG) scores, and self-reported Western Ontario and McMaster Universities Osteoarthritis (WOMAC) pain, stiffness, and function scores. Bone-capsule distance (BCD) measurements of inflammation on hip ultrasound and MRI were measured at three locations: the proximal-most uncovered portion of the femoral head, the superficial-most (apex) portion of the femoral head, and the largest fluid pocket at the femoral neck.

RESULTS

Ultrasound and MRI BCD correlated with each other significantly and strongly at the apex and neck. Power Doppler findings did not correlate significantly with any other imaging indices. Eight weeks post-injection, WOMAC pain, function, and stiffness scores significantly improved and TUG time improved nearly to the level of significance, but there were no significant changes in ultrasound, MRI, or Doppler indices. Baseline variables were not significantly different between responder and nonresponder WOMAC pain or TUG time cohorts.

CONCLUSION

Basic measures of inflammation on ultrasound and MRI are highly related to each other, but provide little insight into patient function and pain after IASI. Other mechanisms to explain improvement in patient status after IASI are likely at work.

Inflammatory and structural changes in vertebral bodies and posterior elements of the spine in axial spondyloarthritis: construct validity, responsiveness and discriminatory ability of the anatomy-based CANDEN scoring system in a randomised placebo-controlled trial

Background

The Canada-Denmark (CANDEN) definitions of spinal MRI lesions allow a detailed anatomy-based evaluation of inflammatory and structural lesions in vertebral bodies and posterior elements of the spine in patients with axial spondyloarthritis (axSpA). The objective was to examine the reliability, responsiveness and discrimination of scores for spinal inflammation, fat, bone erosion and new bone formation based on the CANDEN system and to describe patterns of inflammatory and structural lesions and their temporal development.

Methods

49 patients with axSpA from an investigator-initiated, randomised, placebo-controlled trial of adalimumab underwent spinal MRI at weeks 0/6/24/48. MR images were scored according to the CANDEN system and the Spondyloarthritis Research Consortium of Canada (SPARCC) method. Total scores, and various subscores, were created by summing individual lesion scores.

Results

The CANDEN spine inflammation score had high responsiveness, similar to the SPARCC MRI spine index (Guyatt’s responsiveness index 1.88 and 1.67, respectively), and discriminated between adalimumab and placebo treatment already at 6 weeks’ follow-up (P=0.03). Anterior/posterior corner inflammation subscores showed similar responsiveness. Inter-reader reliability for the CANDEN spine inflammation and fat scores was good to very good for status and change scores (intraclass correlation coefficient (ICC)=0.71–0.92). Reliability for CANDEN new bone formation and erosion scores was good to very good for status scores (ICC=0.61–0.75) but, due to minimal progression, poor for change scores (ICC≤0.40).

Conclusions

The CANDEN spine inflammation score showed good responsiveness, discrimination between active treatment and placebo and reliability. The CANDEN spine structural scores had good cross-sectional reliability, but longer studies are needed to investigate their sensitivity to change.

Trial registration number

NCT01029847; Results.

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.

Validation of a Knowledge Transfer Tool According to the OMERACT Filter: Does Web-based Real-time Iterative Calibration Enhance the Evaluation of Bone Marrow Lesions in Hip Osteoarthritis?

OBJECTIVE

To assess reliability and feasibility of using a Web-based interface and interactive online calibration tool for magnetic resonance imaging (MRI) scoring of bone marrow lesions (BML) in osteoarthritis (OA), applied to the Hip MR Inflammation Scoring System (HIMRISS).

METHODS

Seven readers new to HIMRISS (3 radiologists, 4 rheumatologists) scored coronal short-tau inversion recovery MRI from a hip OA observational study obtained pre- and 8-week poststeroid injection (n = 40 × 2 scans × 2 hips = 160 hips). By crossover design, Group B (4 readers) scored 20 patients (40 hips) using conventional spreadsheet-based methods and then another 20 using a Web-based interface and an online real-time iterative calibration (RETIC) training module. Group A (3 readers) reversed the order, scoring the first 20 subjects by the new method and the final 20 conventionally. Outcomes included ICC and reader survey.

RESULTS

Interobserver reliability for BML status was high by both spreadsheet and Web-based methods (0.84-0.90), regardless of the order in which scoring was performed. Reliability of change scores was moderate and improved with training. Improvement was greater in readers who began with the spreadsheet method and then used the Web-based method than in those who began with the Web-based method, especially at the acetabulum. Readers found Web-based/RETIC scoring more user-friendly and nearly 50% faster than traditional spreadsheet methods.

CONCLUSION

HIMRISS offers reliable BML scoring in OA, whether by conventional spreadsheet-based scoring or by a Web-based interface with interactive feedback. The new method allowed faster readings, provided a consistent training environment that helped inexperienced readers achieve reliability equivalent to that of conventional methods, and was preferred by the readers.

Whole-body Magnetic Resonance Imaging in Inflammatory Arthritis: Systematic Literature Review and First Steps Toward Standardization and an OMERACT Scoring System

OBJECTIVE

Whole-body magnetic resonance imaging (WB-MRI) is a relatively new technique that can enable assessment of the overall inflammatory status of people with arthritis, but standards for image acquisition, definitions of key pathologies, and a quantification system are required. Our aim was to perform a systematic literature review (SLR) and to develop consensus definitions of key pathologies, anatomical locations for assessment, a set of MRI sequences and imaging planes for the different body regions, and a preliminary scoring system for WB-MRI in inflammatory arthritis.

METHODS

An SLR was initially performed, searching for WB-MRI studies in arthritis, osteoarthritis, spondyloarthritis, or enthesitis. These results were presented to a meeting of the MRI in Arthritis Working Group together with an MR image review. Following this, preliminary standards for WB-MRI in inflammatory arthritides were developed with further iteration at the Working Group meetings at the Outcome Measures in Rheumatology (OMERACT) 2016.

RESULTS

The SLR identified 10 relevant original articles (7 cross-sectional and 3 longitudinal, mostly focusing on synovitis and/or enthesitis in spondyloarthritis, 4 with reproducibility data). The Working Group decided on inflammation in peripheral joints and entheses as primary focus areas, and then developed consensus MRI definitions for these pathologies, selected anatomical locations for assessment, agreed on a core set of MRI sequences and imaging planes for the different regions, and proposed a preliminary scoring system. It was decided to test and further develop the system by iterative multireader exercises.

CONCLUSION

These first steps in developing an OMERACT WB-MRI scoring system for use in inflammatory arthritides offer a framework for further testing and refinement.

The OA Trial Bank: meta-analysis of individual patient data from knee and hip osteoarthritis trials show that patients with severe pain exhibit greater benefit from intra-articular glucocorticoids

OBJECTIVE

To evaluate the efficacy of intra-articular (IA) glucocorticoids for knee or hip osteoarthritis (OA) in specific subgroups of patients with severe pain and inflammatory signs using individual patient data (IPD) from existing trials.

DESIGN

Randomized trials evaluating one or more IA glucocorticoid preparation in patients with knee or hip OA, published from 1995 up to June 2012 were selected from the literature. IPD obtained from original trials included patient and disease characteristics and outcomes measured. The primary outcome was pain severity at short-term follow-up (up to 4 weeks). The subgroup factors assessed included severe pain (≥70 points, 0-100 scale) and signs of inflammation (dichotomized in present or not) at baseline. Multilevel regression analyses were applied to estimate the magnitude of the effects in the subgroups with the individuals nested within each study.

RESULTS

Seven out of 43 published randomized clinical trials (n = 620) were included. Patients with severe baseline pain had a significantly larger reduction in short-term pain, but not in mid- and long-term pain, compared to those with less severe pain at baseline (Mean Difference 13.91; 95% Confidence Interval 1.50-26.31) when receiving IA glucocorticoid injection compared to placebo. No statistical significant interaction effects were found between inflammatory signs and IA glucocorticoid injections compared to placebo and to tidal irrigation at all follow-up points.

CONCLUSIONS

This IPD meta-analysis demonstrates that patients with severe knee pain at baseline derive more benefit from IA glucocorticoid injection at short-term follow-up than those with less severe pain at baseline.

Defining active sacroiliitis on MRI for classification of axial spondyloarthritis: update by the ASAS MRI working group

Objectives

To review and update the existing definition of a positive MRI for classification of axial spondyloarthritis (SpA).

Methods

The Assessment in SpondyloArthritis International Society (ASAS) MRI working group conducted a consensus exercise to review the definition of a positive MRI for inclusion in the ASAS classification criteria of axial SpA. Existing definitions and new data relevant to the MRI diagnosis and classification of sacroiliitis and spondylitis in axial SpA, published since the ASAS definition first appeared in print in 2009, were reviewed and discussed. The precise wording of the existing definition was examined in detail and the data and a draft proposal were presented to and voted on by the ASAS membership.

Results

The clear presence of bone marrow oedema on MRI in subchondral bone is still considered to be the defining observation that determines the presence of active sacroiliitis. Structural damage lesions seen on MRI may contribute to a decision by the observer that inflammatory lesions are genuinely due to SpA but are not required to meet the definition. The existing definition was clarified adding guidelines and images to assist in the application of the definition.

Conclusion

The definition of a positive MRI for classification of axial SpA should continue to primarily depend on the imaging features of ‘active sacroiliitis’ until more data are available regarding MRI features of structural damage in the sacroiliac joint and MRI features in the spine and their utility when used for classification purposes.

Does evaluation of the ligamentous compartment enhance diagnostic utility of sacroiliac joint MRI in axial spondyloarthritis?

Introduction

Inflammation of the sacroiliac joints (SIJ) is a fundamental clinical feature of axial spondyloarthritis (SpA). The anatomy of the irregularly shaped SIJ is complex with an antero-inferior cartilaginous compartment containing central hyaline and peripheral fibrocartilage, and a dorso-superior ligamentous compartment. Several scoring modules to systematically assess SIJ magnetic resonance imaging (MRI) in SpA have been developed. Nearly all of them are based on the cartilaginous joint compartment alone. However, there are only limited data about the frequency of inflammatory lesions in the ligamentous compartment and their potential diagnostic utility in axial SpA. We therefore aimed to evaluate the ligamentous compartment on sacroiliac joint MRI for lesion distribution and potential incremental value towards diagnosis of SpA over and above the traditional assessment of the cartilaginous compartment alone.

Methods

Two independent cohorts of 69 and 88 consecutive back pain patients ≤50 years were referred for suspected SpA (cohort A) or acute anterior uveitis plus back pain (cohort B). Patients were classified according to rheumatologist expert opinion based on clinical, radiographic and laboratory examination as having nonradiographic axial SpA (nr-axSpA; n = 51), ankylosing spondylitis (n = 34), or nonspecific back pain (NSBP; n = 72). Five blinded readers assessed SIJ MRI globally for presence/absence of SpA. Bone marrow edema (BME) and fat metaplasia were recorded in the cartilaginous and ligamentous compartment. The incremental value of evaluating the ligamentous additionally to the cartilaginous compartment alone for diagnosis of SpA was graded qualitatively. We determined the lesion distribution between the two compartments, and the impact of the ligamentous compartment evaluation on diagnostic utility.

Results

MRI bone marrow lesions solely in the ligamentous compartment in the absence of lesions in the cartilaginous compartment were reported in just 0–2.0/0–4.0 % (BME/fat metaplasia) of all subjects. Additional assessment of the ligamentous compartment was regarded as essential for diagnosis in 0 and 0.6 %, and as contributory in 28.0 and 7.7 % of nr-axSpA patients in cohorts A and B, respectively. Concomitant BME in both compartments was evident in 11.6–42.0 % of nr-axSpA and 2.1–2.4 % of NSBP patients.

Conclusion

Assessing the ligamentous compartment on SIJ MRI provided no incremental value for diagnosis of axial SpA. However, concomitant BME in both compartments may help discriminate nr-axSpA from NSBP.

Percutaneous vertebroplasty for osteoporotic vertebral compression fracture

BACKGROUND

Percutaneous vertebroplasty is widely used to treat acute and subacute painful osteoporotic vertebral fractures although recent placebo-controlled trials have questioned its value.

OBJECTIVES

To synthesise the available evidence regarding the benefits and harms of vertebroplasty for treatment of osteoporotic vertebral fractures.

SEARCH METHODS

We searched CENTRAL, MEDLINE and EMBASE up to November 2014. We also reviewed reference lists of review articles, trials and trial registries to identify any other potentially relevant trials.

SELECTION CRITERIA

We included randomised and quasi-randomised controlled trials (RCTs) including adults with painful osteoporotic vertebral fractures of any duration and comparing vertebroplasty with placebo (sham), usual care, or any other intervention. As it is least prone to bias, vertebroplasty compared with placebo was the primary comparison. Major outcomes were mean overall pain, disability, disease-specific and overall health-related quality of life, patient-reported treatment success, new symptomatic vertebral fractures and number of other serious adverse events.

DATA COLLECTION AND ANALYSIS

At least two review authors independently selected trials for inclusion, extracted data, performed 'Risk of bias' assessment and assessed the quality of the body of evidence for the main outcomes using GRADE.

MAIN RESULTS

Eleven RCTs and one quasi-RCT conducted in various countries were included. Two trials compared vertebroplasty with placebo (209 randomised participants), six compared vertebroplasty with usual care (566 randomised participants) and four compared vertebroplasty with kyphoplasty (545 randomised participants). Trial size varied from 34 to 404 participants, most participants were female, mean age ranged between 63.3 and 80 years, and mean symptom duration varied from a week to more than six months.Both placebo-controlled trials were judged to be at low overall risk of bias while other included trials were generally considered to be at high risk of bias across a range of criteria, most seriously due to lack of participant and study personnel blinding.Compared with placebo, there was moderate quality evidence based upon two trials that vertebroplasty provides no demonstrable benefits with respect to pain, disability, disease-specific or overall quality of life or treatment success. At one month, mean pain (on a scale 0 to 10, higher scores indicate more pain) was 5 points with placebo and 0.7 points better (1.5 better to 0.15 worse) with vertebroplasty, an absolute pain reduction of 7% (15% better to 1.5% worse) and relative reduction of 10% (21% better to 2% worse) (two trials, 201 participants). At one month, mean disability measured by the Roland Morris Disability Questionnaire (scale range 0 to 23, higher scores indicate worse disability) was 13.6 points in the placebo group and 1.1 points better (2.9 better to 0.8 worse) in the vertebroplasty group, absolute improvement in disability 4.8% (12.8% better to 3.3% worse), relative change 6.3% better (17.0% better to 4.4% worse) (two trials, 201 participants).At one month, disease-specific quality of life measured by the QUALEFFO (scale 0 to 100, higher scores indicating worse quality of life) was 2.4 points in the placebo group and 0.40 points worse (4.58 better to 5.38 worse) in the vertebroplasty group, absolute change: 0.4% worse (5% worse to 5% better), relative change 0.7% worse (9% worse to 8% better (based upon one trial, 73 participants). At one month overall quality of life measured by the EQ5D (0 = death to 1 = perfect health, higher scores indicate greater quality of life at one month was 0.27 points in the placebo group and 0.05 points better (0.01 worse to 0.11 better) in the vertebroplasty group, absolute improvement in quality of life 5% (1% worse to 11% better), relative change 18% better (4% worse to 39% better) (two trials, 201 participants). Based upon one trial (78 participants) at one month, 9/40 (or 225 per 1000) people perceived that treatment was successful in the placebo group compared with 12/38 (or 315 per 1000; range 150 to 664) in the vertebroplasty group, RR 1.40 (95% CI 0.67 to 2.95), absolute risk difference 9% more reported success (11% fewer to 29% more); relative change 40% more reported success (33% fewer to 195% more).Based upon moderate quality evidence from three trials (one placebo, two usual care, 281 participants) with up to 12 months follow-up, we are uncertain whether or not vertebroplasty increases the risk of new symptomatic vertebral fractures (28/143 observed in the vertebroplasty group compared with 19/138 in the control group; RR 1.47 (95% CI 0.39 to 5.50).Similary, based upon moderate quality evidence from two placebo-controlled trials (209 participants), we are uncertain about the exact risk of other adverse events (3/106 were observed in the vertebroplasty group compared with 3/103 in the placebo group; RR 1.01 (95% CI 0.21 to 4.85)). Notably, serious adverse events reported with vertebroplasty included osteomyelitis, cord compression, thecal sac injury and respiratory failure.Our subgroup analyses provided limited evidence that the effects did not differ according to duration of pain ≤ 6 weeks versus > 6 weeks. Including data from the six trials that compared vertebroplasty with usual care in a sensitivity analyses inconsistently altered the primary results, with all combined analyses displaying substantial to considerable heterogeneity.

AUTHORS' CONCLUSIONS

Based upon moderate quality evidence, our review does not support a role for vertebroplasty for treating osteoporotic vertebral fractures in routine practice. We found no demonstrable clinically important benefits compared with a sham procedure and subgroup analyses indicated that results did not differ according to duration of pain ≤ 6 weeks versus > 6 weeks. Sensitivity analyses confirmed that open trials comparing vertebroplasty with usual care are likely to have overestimated any benefit of vertebroplasty. Correcting for these biases would likely drive any benefits observed with vertebroplasty towards the null, in keeping with findings from the placebo-controlled trials.Numerous serious adverse events have been observed following vertebroplasty. However due to the small number of events, we cannot be certain about whether or not vertebroplasty results in a clinically important increased risk of new symptomatic vertebral fractures and/or other serious adverse events. Patients should be informed about both the lack of high quality evidence supporting benefit of vertebroplasty and its potential for harm.

The FAt Spondyloarthritis Spine Score (FASSS): development and validation of a new scoring method for the evaluation of fat lesions in the spine of patients with axial spondyloarthritis

Introduction

Studies have shown that fat lesions follow resolution of inflammation in the spine of patients with axial spondyloarthritis (SpA). Fat lesions at vertebral corners have also been shown to predict development of new syndesmophytes. Therefore, scoring of fat lesions in the spine may constitute both an important measure of treatment efficacy as well as a surrogate marker for new bone formation. The aim of this study was to develop and validate a new scoring method for fat lesions in the spine, the Fat SpA Spine Score (FASSS), which in contrast to the existing scoring method addresses the localization and phenotypic diversity of fat lesions in patients with axial SpA.

Methods

Fat lesions at pre-specified anatomical locations at each vertebral endplate (C2 lower-S1 upper) were assessed dichotomously (present/absent) on spine MRIs. Two readers independently evaluated MRIs obtained at two time points for 58 patients (Exercise 1), followed by optimization of scoring methodology and reader calibration. Thereafter, the same readers read 135 pairs of MRI scans (Exercise 2; including the 58 pairs from exercise 1 randomly mixed with 77 new pairs).

Results

In Exercise 2, the mean (SD) baseline FASSS score for the two readers was 22.5(29.6) and 21.1(28.0), respectively, and the FASSS change score was 4.2(10.6) and 6.0(12.2). Inter-reader reliability assessed as intra-class correlation coefficients (ICCs) for status and change scores were excellent (0.96 (95% CI (0.94 to 0.97)) and very good (0.86 (0.80 to 0.90)), respectively. The smallest detectable change (SDC) was 3.7 for the 135 patients. Good reliability of change scores was also observed for MRI scans conducted one year apart (ICC 0.74 (95% CI 0.44 to 0.89) and SDC 4.5). For the 58 MRI-pairs assessed in both exercises, inter-reader reproducibility for the total FASSS status score improved from very good (ICCs: 0.89 (95% CI: 0.81 to 0.93) in exercise 1 to excellent in exercise 2 (0.96 (0.93 to 0.98)), and improved substantially for the total change score (from 0.67 (0.51 to 0.80) to 0.83 (0.73 to 0.90).

Conclusions

FASSS meets essential validation criteria for quantification of a common structural abnormality in clinical trials of axial spondyloarthritis.

Spinal inflammation in the absence of sacroiliac joint inflammation on magnetic resonance imaging in patients with active nonradiographic axial spondyloarthritis

OBJECTIVE

To evaluate the presence of spinal inflammation with and without sacroiliac (SI) joint inflammation on magnetic resonance imaging (MRI) in patients with active nonradiographic axial spondyloarthritis (SpA), and to compare the disease characteristics of these subgroups.

METHODS

ABILITY-1 is a multicenter, randomized, controlled trial of adalimumab versus placebo in patients with nonradiographic axial SpA classified using the Assessment of SpondyloArthritis international Society axial SpA criteria. Baseline MRIs were centrally scored independently by 2 readers using the Spondyloarthritis Research Consortium of Canada (SPARCC) method for the SI joints and the SPARCC 6-discovertebral unit method for the spine. Positive evidence of inflammation on MRI was defined as a SPARCC score of ≥2 for either the SI joints or the spine.

RESULTS

Among patients with baseline SPARCC scores, 40% had an SI joint score of ≥2 and 52% had a spine score of ≥2. Forty-nine percent of patients with baseline SI joint scores of <2, and 58% of those with baseline SI joint scores of ≥2, had a spine score of ≥2. Comparison of baseline disease characteristics by baseline SI joint and spine scores showed that a greater proportion of patients in the subgroup with a baseline SPARCC score of ≥2 for both SI joints and spine were male, and patients with spine and SI joint scores of <2 were younger and had shorter symptom duration. SPARCC spine scores correlated with baseline symptom duration, and SI joint scores correlated negatively with the baseline Bath Ankylosing Spondylitis Disease Activity Index, but neither correlated with the baseline Ankylosing Spondylitis Disease Activity Score, total back pain, the patient's global assessment of disease activity, the Bath Ankylosing Spondylitis Functional Index, morning stiffness, nocturnal pain, or C-reactive protein level.

CONCLUSION

Assessment by experienced readers showed that spinal inflammation on MRI might be observed in half of patients with nonradiographic axial SpA without SI joint inflammation.

Fat infiltration on magnetic resonance imaging of the sacroiliac joints has limited diagnostic utility in nonradiographic axial spondyloarthritis

OBJECTIVE

To explore whether morphological features of fat infiltration (FI) on sacroiliac joint (SIJ) magnetic resonance imaging (MRI) contribute to diagnostic utility in 2 inception cohorts of patients with nonradiographic axial spondyloarthritis (nr-axSpA).

METHODS

Four blinded readers assessed SIJ MRI in 2 cohorts (A/B) of 157 consecutive patients with back pain who were ≤ 50 years old, and in 20 healthy controls. Patients were classified according to clinical examination and pelvic radiography as having nr-axSpA (n = 51), ankylosing spondylitis (n = 34), or nonspecific back pain (n = 72). Readers recorded FI, bone marrow edema (BME), and erosion, predefined morphological features of FI (distinct border, homogeneity, subchondral location), and anatomical distribution of SIJ FI. The proportion of SIJ quadrants affected by FI and frequencies of various SIJ FI features were analyzed descriptively. We calculated positive/negative likelihood ratios (LR) to estimate the diagnostic utility of various features of FI, with and without associated BME, and erosion.

RESULTS

Of the patients with nr-axSpA in cohorts A/B, 45.0%/48.4% had FI in ≥ 2 SIJ quadrants. Of those, 25.0%/22.6% and 20.0%/25.8% showed FI with distinct border or homogeneous pattern, respectively, and 50% to 100% of those patients displayed concomitant BME or erosion. FI per se in ≥ 2 SIJ quadrants had no diagnostic utility (LR+ 1.62/1.91). FI with distinct border (LR+ 8.29/2.13) or homogeneity (LR+ 6.24/3.78) demonstrated small to moderate diagnostic utility.

CONCLUSION

SIJ FI per se was not of clinical utility in recognition of nr-axSpA. Distinct border or homogeneity of FI on SIJ MRI showed small to moderate diagnostic utility in nr-axSpA, but were strongly associated with concomitant BME or erosion, highlighting the contextual interpretation of SIJ MRI.

Methodologies for semiquantitative evaluation of hip osteoarthritis by magnetic resonance imaging: approaches based on the whole organ and focused on active lesions

OBJECTIVE

As a wider variety of therapeutic options for osteoarthritis (OA) becomes available, there is an increasing need to objectively evaluate disease severity on magnetic resonance imaging (MRI). This is more technically challenging at the hip than at the knee, and as a result, few systematic scoring systems exist. The OMERACT (Outcome Measures in Rheumatology) filter of truth, discrimination, and feasibility can be used to validate image-based scoring systems. Our objective was (1) to review the imaging features relevant to the assessment of severity and progression of hip OA; and (2) to review currently used methods to grade these features in existing hip OA scoring systems.

METHODS

A systematic literature review was conducted. MEDLINE keyword search was performed for features of arthropathy (such as hip + bone marrow edema or lesion, synovitis, cyst, effusion, cartilage, etc.) and scoring system (hip + OA + MRI + score or grade), with a secondary manual search for additional references in the retrieved publications.

RESULTS

Findings relevant to the severity of hip OA include imaging markers associated with inflammation (bone marrow lesion, synovitis, effusion), structural damage (cartilage loss, osteophytes, subchondral cysts, labral tears), and predisposing geometric factors (hip dysplasia, femoral-acetabular impingement). Two approaches to the semiquantitative assessment of hip OA are represented by Hip OA MRI Scoring System (HOAMS), a comprehensive whole organ assessment of nearly all findings, and the Hip Inflammation MRI Scoring System (HIMRISS), which selectively scores only active lesions (bone marrow lesion, synovitis/effusion). Validation is presently confined to limited assessment of reliability.

CONCLUSION

Two methods for semiquantitative assessment of hip OA on MRI have been described and validation according to the OMERACT Filter is limited to evaluation of reliability.

Advanced imaging of the axial skeleton in spondyloarthropathy: techniques, interpretation, and utility

The development of available treatments for spondyloarthritis increases the need for accurate diagnosis and objective monitoring of response to therapy. Advances in MRI technology are improving the effectiveness of imaging of the sacroiliac joints and spine in spondyloarthritis. We discuss best practice techniques for MR image acquisition and interpretation with a view to optimizing the diagnostic utility of MRI in spondyloarthritis.

Targeting tumour necrosis factor alleviates signs and symptoms of inflammatory osteoarthritis of the knee

INTRODUCTION

Inflammation associated with synovial expression of TNFα is a recognised feature of osteoarthritis (OA), although no studies have yet reported beneficial effects of anti-TNFα therapy on clinical manifestations of inflammation in OA.

METHODS

We conducted an open-label evaluation of adalimumab over 12 weeks in 20 patients with OA of the knee and evidence of effusion clinically. Inclusion criteria included daily knee pain for the month preceding study enrolment and a summed pain score of 125 to 400 mm visual analogue scale on the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) pain subscale. The primary outcome was the Osteoarthritis Research Society International/Outcome Measures in Rheumatology Clinical Trials (OARSI/OMERACT) response criterion at week 12. Secondary outcomes included the WOMAC pain score 20% and 50% improvement, WOMAC stiffness and function scores, patient and physician global visual analogue scale, as well as target joint swelling.

RESULTS

Treatment was well tolerated and completed by 17 patients with withdrawals unrelated to lack of efficacy or adverse events. By intention to treat, an OARSI/OMERACT response was recorded in 14 (70%) patients. WOMAC pain 20% and 50% responses were recorded in 14 (70%) patients and eight (40%) patients, respectively. Significant improvement was observed in mean WOMAC pain, stiffness, function, physician and patient global, as well as target joint swelling at 12 weeks (P < 0.0001 for all). After treatment discontinuation, 16 patients were available for assessment at 22 weeks and OARSI/OMERACT response compared with baseline was still evident in 10 (50%) patients.

CONCLUSION

Targeting TNFα may be of therapeutic benefit in OA and requires further evaluation in controlled trials.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00686439.

Imaging in ankylosing spondylitis

Imaging is an integral part of the management of patients with ankylosing spondylitis and axial spondyloarthritis. Characteristic radiographic and/or magnetic resonance imaging (MRI) findings are key in the diagnosis. Radiography and MRI are also useful in monitoring the disease. Radiography is the conventional, albeit quite insensitive, gold standard method for assessment of structural damage in spine and sacroiliac joints, whereas MRI has gained a decisive role in monitoring disease activity in clinical trials and practice. MRI may also, if ongoing research demonstrates a sufficient reliability and sensitivity to change, become a new standard method for assessment of structural damage. Ultrasonography allows visualization of peripheral arthritis and enthesitis, but has no role in the assessment of axial manifestations. Computed tomography is a sensitive method for assessment of structural changes in the spine and sacroiliac joints, but its clinical utility is limited due to its use of ionizing radiation and lack of ability to assess the soft tissues. It is exciting that with continued dedicated research and the rapid technical development it is likely that even larger improvements in the use of imaging may occur in the decade to come, for the benefit of our patients.

Can erosions on MRI of the sacroiliac joints be reliably detected in patients with ankylosing spondylitis? - A cross-sectional study

INTRODUCTION

Erosions of the sacroiliac joints (SIJ) on pelvic radiographs of patients with ankylosing spondylitis (AS) are an important feature of the modified New York classification criteria. However, radiographic SIJ erosions are often difficult to identify. Recent studies have shown that erosions can be detected also on magnetic resonance imaging (MRI) of the SIJ early in the disease course before they can be seen on radiography. The goals of this study were to assess the reproducibility of erosion and related features, namely, extended erosion (EE) and backfill (BF) of excavated erosion, in the SIJ using a standardized MRI methodology.

METHODS

Four readers independently assessed T1-weighted and short tau inversion recovery sequence (STIR) images of the SIJ from 30 AS patients and 30 controls (15 patients with non-specific back pain and 15 healthy volunteers) ≤ 45 years old. Erosions, EE, and BF were recorded according to standardized definitions. Reproducibility was assessed by percentage concordance among six possible reader pairs, kappa statistics (erosion as binary variable) and intraclass correlation coefficient (ICC) (erosion as sum score) for all readers jointly.

RESULTS

SIJ erosions were detected in all AS patients and six controls by ≥ 2 readers. The median number of SIJ quadrants affected by erosion recorded by four readers in 30 AS patients was 8.6 in the iliac and 2.1 in the sacral joint portion (P < 0.0001). For all 60 subjects and for all four readers, the kappa value for erosion was 0.72, 0.73 for EE, and 0.63 for BF. ICC for erosion was 0.79, 0.72 for EE, and 0.55 for BF, respectively. For comparison, the kappa and ICC values for bone marrow edema were 0.61 and 0.93, respectively.

CONCLUSIONS

Erosions can be detected on MRI to a comparable degree of reliability as bone marrow edema despite the significant heterogeneity of their appearance on MRI.

The diagnostic utility of magnetic resonance imaging in spondylarthritis: an international multicenter evaluation of one hundred eighty-seven subjects

OBJECTIVE

To systematically assess the diagnostic utility of magnetic resonance imaging (MRI) to differentiate patients with spondylarthritis (SpA) from patients with nonspecific back pain and healthy volunteers, using a standardized evaluation of MR images of the sacroiliac joints.

METHODS

Five readers blinded to the patients and diagnoses independently assessed MRI scans (T1-weighted and STIR sequences) of the sacroiliac joints obtained from 187 subjects: 75 patients with ankylosing spondylitis (AS; symptom duration ≤ 10 years), 27 patients with preradiographic inflammatory back pain (IBP; mean symptom duration 29 months), 26 patients with nonspecific back pain, and 59 healthy control subjects; all participants were age 45 years or younger. Bone marrow edema, fat infiltration, erosion, and ankylosis were recorded according to standardized definitions using an online data entry system. We calculated sensitivity, specificity, and positive and negative likelihood ratios (LRs) for the diagnosis of SpA based on global assessment of the MRI scans.

RESULTS

Diagnostic utility was high for all 5 readers, both for patients with AS (sensitivity 0.90, specificity 0.97, positive LR 44.6) and for patients with preradiographic IBP (sensitivity 0.51, specificity 0.97, positive LR 26.0). Diagnostic utility based solely on detection of bone marrow edema enhanced sensitivity (67%) for patients with IBP but reduced specificity (88%); detection of erosions in addition to bone marrow edema further enhanced sensitivity (81%) without changing specificity. A single lesion of the sacroiliac joint on MRI was observed in up to 27% of control subjects.

CONCLUSION

This systematic and standardized evaluation of sacroiliac joints in patients with SpA showed that MRI has much greater diagnostic utility than has been documented previously. We present for the first time a data-driven definition of MRI-visualized positivity for SpA.

Vertebroplasty for osteoporotic vertebral fracture

Consensus on the indications is needed to avoid indiscriminate use

Scoring inflammatory activity of the spine by magnetic resonance imaging in ankylosing spondylitis: a multireader experiment

OBJECTIVE

Magnetic resonance imaging (MRI) of the spine is increasingly important in the assessment of inflammatory activity in clinical trials with patients with ankylosing spondylitis (AS). We investigated feasibility, inter-reader reliability, sensitivity to change, and discriminatory ability of 3 different scoring methods for MRI activity and change in activity of the spine in patients with AS.

METHODS

Thirty sets of spinal MRI at baseline and after 24 weeks of followup, derived from a randomized clinical trial comparing a tumor necrosis factor (TNF)-blocking drug (n = 20) with placebo (n = 10) and selected to cover a wide range of activity at baseline and change in activity, were presented electronically in a partial latin-square design to 9 experienced readers from different countries (Europe, Canada). Readers scored each set of MRI 3 times, using 3 different methods including the Ankylosing Spondylitis spine Magnetic Resonance Imaging-activity [ASspiMRI-a, grading activity (0-6) per vertebral unit in 23 units]; the Berlin modification of the ASspiMRI-a; and the Spondyloarthritis Research Consortium of Canada (SPARCC) scoring system, which scores the 6 vertebral units considered by the reader as the most abnormal, with additional scores for "depth" and "intensity." Both the order of the methods used by each reader and the timepoints (before/after treatment) were randomized. Feasibility of each scoring system was evaluated by measuring the mean time needed to score each set of MRI, and inter-reader reliability was evaluated by smallest detectable change (SDC) and by intraclass correlation coefficients (ICC) for all readers together and for all possible reader pairs separately. Sensitivity to change was investigated by calculating Guyatt's effect size on change scores. Discriminatory ability was assessed using Z-scores (Mann-Whitney test) comparing change in score between patients treated with TNF-blocking drug and placebo.

RESULTS

The mean time to score one set of MRI was shortest for the Berlin method. SDC was lowest for the Berlin method and highest for SPARCC. Overall inter-reader ICC per method were between 0.49 and 0.77 for scoring activity status, and between 0.46 and 0.72 for scoring activity change. ICC for all possible reader pairs showed much more fluctuation per method, with lowest observed values of about 0.05 (very low agreement) and highest observed values over 0.90 (excellent agreement). In general, ICC for SPARCC were consistently higher than for other systems. Sensitivity to change differed per reader, and was more consistent with SPARCC than with the other methods, but was in general excellent for all 3 methods. Discrimination between groups (TNF-blocker vs placebo) assessed by Z-scores was good and comparable among methods.

CONCLUSION

This experiment demonstrates the feasibility of multiple-reader MRI scoring exercises for method comparison, provides evidence for the feasibility, reliability, sensitivity to change, and discriminatory capacity of all 3 tested scoring systems to be used in assessing spinal activity on MRI in patients with AS in clinical trials. On the basis of these results it is not possible to prioritize one of the 3 methods.

Accuracy and reliability of MRI vs. laboratory measurements in an ex vivo porcine model of arthritic cartilage loss

PURPOSE

To quantify the accuracy of magnetic resonance imaging (MRI) measurement of change in cartilage volume due to thin linear excisions, simulating arthritic cartilage losses, by comparison with laboratory volume measurements in an ex vivo porcine model.

MATERIALS AND METHODS

We scanned 15 porcine patellae by T1-weighted spoiled gradient echo (SPGR) MRI at baseline and after excision of up to three thin layers of articular cartilage. Excised fragment volume was determined from density and weight. Postexcision scans were "fused" to the baseline scan by three-dimensional (3D) registration. This allowed automated recalculation of the remaining cartilage volume within a baseline region of interest (ROI) following each excision. We compared MRI estimates of change in cartilage volume to direct laboratory measurement of fragment volume.

RESULTS

Our 38 excised fragments averaged 0.16 mL, or approximately 7% of cartilage volume. MRI and laboratory estimates of total cartilage volume loss differed by 1.6% +/- 13.2% (mean, coefficient of variation [CV]). Accuracy was +/-0.1 mL for 95% of scans.

CONCLUSION

MRI estimates of small changes in porcine patellar cartilage volume were unbiased, reliable, and accurate to 0.1 mL. Despite a proportionately high error in the very thin fragments tested, achievement of similar accuracy in vivo would be adequate to detect approximately two years of osteoarthritic cartilage loss.

Steroid injection for osteoarthritis of the hip: A randomized, double-blind, placebo-controlled trial

OBJECTIVE

To determine the efficacy of fluoroscopically guided corticosteroid injection for hip osteoarthritis (OA) in a randomized, double-blind, placebo-controlled trial.

METHODS

Fifty-two patients with symptomatic hip OA were randomly allocated to receive placebo (10 mg bipuvicaine, 2 ml saline) (n = 21) or corticosteroid treatment (10 mg bipuvicaine, 40 mg triamcinolone hexacetonide) (n = 31). Patients were followed up for 1, 2, 3, and 6 months. The primary outcome measure was the pain improvement response, defined as a 20% decrease in the Western Ontario and McMaster Universities OA Index (WOMAC) pain score (on 5 100-mm visual analog scales [VAS]) (WOMAC20) from baseline to 2 months postinjection. Secondary outcomes were a 50% decrease in the WOMAC pain score (WOMAC50), changes in other WOMAC subscale scores, patient's global assessment of health (on a 100-mm VAS), and Short Form 36 (SF-36) quality of life indices. Analyses were based on the intent-to-treat principle.

RESULTS

The mean WOMAC pain score fell 49.2% (decreasing from 310.1 mm to 157.4 mm) at 2 months postinjection in patients receiving corticosteroid, compared with a decrease of 2.5% (from 314.3 mm to 306.5 mm) in the placebo group (P < 0.0001). The proportion of WOMAC20 responders at 2 months' followup was significantly higher in the corticosteroid group (67.7%) compared with the placebo group (23.8%) (P = 0.004); similar proportions of WOMAC50 responders were observed between groups (61.3% in the corticosteroid group versus 14.3% in the placebo group; P = 0.001). Response differences were maintained at 3 months' followup (58.1% responders in the corticosteroid group versus 9.5% responders in the placebo group; P = 0.004). Significant differences in the WOMAC stiffness and physical function scores (P < 0.0001), patient's global health scores (P = 0.005), and SF-36 physical component scores (P = 0.04) were observed, with patients in the corticosteroid group showing greater improvements. There were no differences in the frequency of adverse events between groups.

CONCLUSION

This placebo-controlled trial confirms that corticosteroid injection can be an effective treatment of pain in hip OA, with benefits lasting up to 3 months in many cases. Future studies should address questions related to the benefits of repeated steroid injection and the effects of this treatment on disease modification.

Validation of the Spondyloarthritis Research Consortium of Canada magnetic resonance imaging spinal inflammation index: Is it necessary to score the entire spine?

OBJECTIVE

The Spondyloarthritis Research Consortium of Canada (SPARCC) magnetic resonance imaging (MRI) spinal inflammation index has been developed to objectively measure inflammation in ankylosing spondylitis (AS) and to assess change in response to therapeutic intervention. Scoring of the entire spine limits feasibility and a scoring method that records inflammation in only the more severely affected spinal segments may improve feasibility without sacrificing performance.

METHODS

MRI films of 68 patients with AS were assessed in random order by 2 blinded readers. Interreader reliability was assessed by intraclass correlation coefficient. Pre- and posttreatment MRI films of 29 patients randomized to placebo or anti-tumor necrosis factor alpha (anti-TNFalpha) therapy were read by readers blinded to chronology, and responsiveness was assessed by effect size and standardized response mean. The performance of scores based on 6, 8, 10, and all 23 spinal discovertebral units (DVU) was compared.

RESULTS

The median number of affected spinal levels per patient was 6.0 and 62% of all affected levels were included when analysis was limited to only the 6 most severely affected levels per patient. Comparison of DVU scores that were limited to only the more severely affected DVU (6-, 8-, 10-DVU score) with scores for all 23 spinal DVU showed excellent interreader reliability for status and change scores (Spearman's correlation >0.90) as well as similar construct validity. Responsiveness to anti-TNFalpha therapy was greater when the more limited scoring methods were used and was greatest with the 6-DVU score.

CONCLUSION

The SPARCC MRI spinal inflammation index performs better when analysis is limited to a maximum of 6 most severely affected levels compared with assessment of the entire spine. This should improve its feasibility in clinical trials and research.

Do radiographic indices of distal radius fracture reduction predict outcomes in older adults receiving conservative treatment?

AIM

To investigate whether radiographic deformities suggesting inadequate reduction would be associated with adverse clinical outcomes.

MATERIALS AND METHODS

Consecutive patients over 50 years of age (n=74) with non-operatively managed distal radius fractures were enrolled in a prospective cohort study. They had radiographs at cast removal ( approximately 6 weeks) and completed DASH (Disabilities of the Arm, Shoulder and Hand), SF-12 (health-related quality of life), and satisfaction surveys 6-months post-fracture. A reference-standard musculoskeletal radiologist, blinded to outcomes status, measured palmar (dorsal) tilt, radial angle, radial height, ulnar height, and intra-articular step and gap. Radiographic indices were correlated to each other and to the various patient-reported outcomes in univariate and multivariate regression analyses. DASH score was the primary study outcome.

RESULTS

Of the cohort studied (n=74, mean age 68.5 years, primarily white women), 71% had at least one "unacceptable" radiographic deformity by traditional criteria. Acceptable reduction varied from 60-99% depending on which single index was reported, and 44% of patients had more than two indices reported as unacceptable. Despite these radiographic findings, 6-months post-reduction, self-reported disability was low (DASH=24+/-17), health-related quality of life was near normal, and 72% were satisfied with their care. No radiographic index of wrist deformity (alone or in combination) was significantly correlated to any of the patient-reported outcomes.

CONCLUSION

Self-reported outcomes in older adults with conservatively managed wrist fractures were not related to the "acceptability" of radiographic fracture reduction. The proportion of acceptable reductions varied by 40% depending on which index was reported. Consequently, detailed reporting of these indices in older adults with distal radius fracture may be inefficient or perhaps even unnecessary.

Humeral head cysts and rotator cuff tears: an MR arthrographic study

OBJECTIVE

Humeral tuberosity cysts are a common finding, with previous reports suggesting they are related to rotator cuff tear or aging. The aim of this study was to investigate the characteristics of cysts in the tuberosities of the humeral head and their relationship with rotator cuff tear and age.

DESIGN AND PATIENTS

Shoulder MR arthrograms were reviewed in 120 consecutive patients-83 males (mean age 38.0, range 19-59 years) and 37 females (mean age 41.2, range 15-59 years). Patients were referred for investigation of a variety of conditions, and instability was suspected in only a minority of cases. MR was performed before and after direct arthrography with 0.01% solution of gadolinium. Cysts were defined as well-demarcated circular/ovoid foci in two planes that demonstrated high signal on pre-arthrographic T2W sequences. Location, size and numbers of cysts and post-arthrographic enhancement were documented, along with the location of rotator cuff tears, if present.

RESULTS

Cysts in the tuberosities of the humerus were identified in 84 patients (70%), and were seen seven times more frequently in the posterior aspect of the greater tuberosity than anteriorly. Most cysts (94%) demonstrated communication with the joint post-arthrogram. Rotator cuff tears were present in 36 patients, and 79% of all tears occurred in supraspinatus tendon. There was no significant difference in the occurrence of cysts between patients older or younger than age 40 or between genders, but rotator cuff tears were seen significantly more often in the older age group (p<0.01). Tuberosity cysts and rotator cuff tears did not appear to be related (p=0.55). However, whilst this lack of association was quite obvious posteriorly (p=0.84), the trend in the anterior aspect of the greater tuberosity is not as clear (p=0.14).

CONCLUSIONS

Humeral cysts are most often located in the posterior aspect of the greater tuberosity, communicate with the joint space and, in this location, are not related to aging or rotator cuff tear.

Transverse morphology of the sacroiliac joint: effect of angulation and implications for fluoroscopically guided sacroiliac joint injection

OBJECTIVE

Effects of angulation of computed tomography (CT) reconstruction plane on sacroiliac (SI) joint morphology were studied, and factors influencing the approach to fluoroscopically guided SI joint injection were assessed.

DESIGN AND PATIENTS

CT scans of pelvises were reformatted on 41 subjects, aged 51.7 (+/-15.1) years. Transverse images were reconstructed at the caudal 3 cm of the SI joint tilting plane of reconstruction from -30 degrees to +30 degrees at 15 degrees increments. Anteroposterior diameter of joint (depth), angle from sagittal plane (orientation angle), and distance from skin were measured. Joint contour was classified, and presence of bone blocking access to the joint was recorded. Comparison between angles were analysed by t-test. Relationships between variables were assessed by a Pearson correlation test.

RESULTS

Depth was shorter with angulation in the inferior direction (P<0.01). Orientation angle increased with superior angulation (P<0.01). Distance from skin increased (P<0.01) with angulation in either direction. Joint contour was significantly different from baseline at each angle (P<0.001) but highly variable. Inferior angulation resulted in interposition of ilium between skin and SI joint, and superior angulation caused bone block due to the lower sacrum. None of these features was identified without tilting of the reconstruction plane, and effects were more pronounced with steeper angulation.

CONCLUSION

Angulation of the reconstruction plane considerably affects the appearance of the sacroiliac joints. By shortening joint depth, an inferiorly directed approach to SI joint injection may make fluoroscopic guidance easier, although associated bony interposition can prevent access to the synovial compartment. A superiorly directed approach is more likely to have adverse effects.