A preliminary study of ultrasound aspiration of bone erosion in early rheumatoid arthritis

The sonographic identification of cortical bone interruptions in rheumatoid arthritis: a morphological approach

Bone erosions are the hallmark of structural damage in rheumatoid arthritis (RA). Among imaging techniques, ultrasonography (US) has emerged as an accurate, reliable, repeatable, low-cost and non-invasive imaging modality to detect erosive changes in RA. However, small interruptions of the cortical bone detectable by last generation US equipment do not necessarily represent bone erosions. According to the available data, in addition to cortical bone interruption itself, only a few morphological US findings have been proposed to define RA bone erosions. However, other additional features may be considered to facilitate the interpretation of US cortical bone interruptions in RA. These could be summarised using the following four domains: size, site, shape and scenery. This hypothesis article provides a critical literature review of US features characteristic of RA bone erosions and pictorial evidence supporting the potential role of a morphological analysis in the US identification of bone erosions in RA patients.

Plain language summary

The ultrasonographic morphology of cortical interruptions is helpful for the identification of bone erosions in rheumatoid arthritis: the "four Ss" approach Bone erosions are characteristic features of rheumatoid arthritis. They are associated with a more aggressive disease and with irreversible physical disability. In recent years, ultrasonography has emerged as an accurate and reliable technique for the detection of bone erosions, that appear as interruptions of the cortical bone with variable size. However, cortical bone interruptions do not necessarily represent bone erosions. Since bone erosions represent the earliest evidence of the destructive behaviour of RA, their identification is crucial.Besides the cortical interruption itself, only a few morphological ultrasonographic features were proposed to characterise bone erosions in rheumatoid arthritis.We believe that a morphological approach, including size, site, shape and scenery, may be considered to facilitate the interpretation of ultrasonographic cortical bone interruptions in rheumatoid arthritis.In this hypothesis article we carried out a critical review of the scientific literature and provided extensive pictorial evidence of the ultrasonographic spectrum of cortical interruptions supporting the potential role of considering the "four Ss" for the ultrasonographic identification of bone erosions in rheumatoid arthritis.

Summary Findings of a Systematic Literature Review of the Ultrasound Assessment of Bone Erosions in Rheumatoid Arthritis

OBJECTIVE

Bone erosions in rheumatoid arthritis (RA) have been studied in an increasing amount of research. Both earlier and present classification criteria of RA contain erosions as a significant classification component. Ultrasound (US) can detect bone changes in accessible surfaces. Therefore, the study group performed a systematic literature review of assessment of RA bone erosions with US.

METHODS

A systematic search of PubMed and Embase was performed. Data on the definitions of RA bone erosions, their size, scoring, relation to synovitis, comparators, and elements of the OMERACT (Outcome Measures in Rheumatology Clinical Trials) filter were collected and analyzed.

RESULTS

The selection process identified 58 original research papers. The assessed joints were most frequently metacarpophalangeal (MCP; 41 papers), proximal interphalangeal (19 papers), and metatarsophalangeal joints (MTP; 18 papers). The OMERACT definition of RA bone erosion on US was used most often (17 papers). Second and fifth MCP and fifth MTP were recommended as target joints. Conventional radiography was the most frequently used comparator (27 papers), then magnetic resonance imaging (17 papers) and computed tomography (5 papers). Reliability of assessment was presented in 20 papers and sensitivity to change in 11 papers.

CONCLUSION

This paper presents results of a systematic literature review of bone erosion assessment in RA with US. The survey suggests that US can be a helpful adjunct to the existing methods of imaging bone erosions in RA. It analyzes definitions, scoring systems, used comparators, and elements of the OMERACT filter. It also presents recommendations for a future research agenda based on the results of the review.

Circulating osteogenic cells: implications for injury, repair, and regeneration

The aim of this review is to provide a critical reading of recent literature pertaining to the presence of circulating, fluid-phase osteoblastic cells and their possible contribution to bone formation. We have termed this group of cells collectively as circulating osteogenic precursor (COP) cells. We present evidence for their existence, methods used for their isolation and identification, possible physiological and pathophysiological roles, cellular origins, and possible mechanisms for their migration to target tissues.

Utility and feasibility of musculoskeletal ultrasonography (MSK US) in rheumatology practice in Canada: needs assessment

The utility of musculoskeletal ultrasound (MSK US) is being extensively explored and evaluated amongst European rheumatologists. However, utilization of MSK US by rheumatologists in Canada is much less common. This study aimed to evaluate the current use of MSK US in Canadian rheumatology practice, to determine beliefs and attitudes towards MSK US, and to determine factors that may encourage or limit its use. A 13-question needs assessment questionnaire was developed. All Canadian rheumatologists were invited via e-mail to participate in the survey. The overall response rate was 156/470 (33%). Fifty-one percent of participants used MSK US in their clinical practice. Lack of training appeared to be the main obstacle to its current use. Eighty-three percent believed that MSK US should be performed by rheumatologists and expressed a willingness to learn the technique. Skills offering greatest clinical utility were the assessment of inflammatory arthritis in small joints (i.e., hands (metacarpophalyngeal and proximal interphalangeal joints), wrists, feet (metatarsophalyngeal), shoulders, and ankles. Limited available time, equipment costs, and difficulties with billing were the main obstacles to MSK US utilization in the clinical setting. There is a great level of interest in learning and applying MSK US in Canadian rheumatology practice. The balance between added clinical value and lack of remuneration, equipment associated costs, and time to complete training is the major limiting factor influencing rheumatologists' willingness to take on MSK US. Training programs must be relevant to rheumatologists' needs before MSK US will be adopted into routine clinical practice in Canada.

Circulating osteogenic precursor cells

Circulating osteogenic precursor (COP) cells are blood-borne cells that express a variety of osteoblastic markers and are able to form bone in vivo. Strong evidence suggests that COP cells are derived from bone marrow and are of hematopoietic origin. The study of COP cells has been limited by several factors, including the difficulty in establishing long-term cultures and lack of a standardized protocol for their isolation and identification. However, experimental evidence supports that COP cells seed sites of injury and inflammation in response to homing signals and are involved in processes of pubertal growth, fracture, and diverse conditions of heterotopic bone formation. The role of COP cells in physiologic and pathophysiologic conditions of de novo bone formation suggests that they may serve as future targets for diagnostic measurements and therapeutic interventions.

Circulating osteogenic precursor cells in heterotopic bone formation

Cells with osteogenic potential can be found in a variety of tissues. Here we show that circulating osteogenic precursor (COP) cells, a bone marrow-derived type I collagen+/CD45+ subpopulation of mononuclear adherent cells, are present in early preosseous fibroproliferative lesions in patients with fibrodysplasia ossificans progressiva (FOP) and nucleate heterotopic ossification (HO) in a murine in vivo implantation assay. Blood samples from patients with FOP with active episodes of HO contain significantly higher numbers of clonally derived COP cell colonies than patients with stable disease or unaffected individuals. The highest level of COP cells was found in a patient just before the clinical onset of an HO exacerbation. Our studies show that even COP cells derived from an unaffected individual can contribute to HO in genetically susceptible host tissue. The possibility that circulating, hematopoietic-derived cells with osteogenic potential can seed inflammatory sites has tremendous implications and, to our knowledge, represents the first example of their involvement in clinical HO. Thus, bone formation is not limited to cells of the mesenchymal lineage, and circulating cells of hematopoietic origin can also serve as osteogenic precursors at remote sites of tissue inflammation.

Utility of synovial biopsy

Synovial biopsies, gained either by blind needle biopsy or minimally invasive arthroscopy, offer additional information in certain clinical situations where routine assessment has not permitted a certain diagnosis. In research settings, synovial histology and modern applications of molecular biology increase our insight into pathogenesis and enable responses to treatment with new therapeutic agents to be assessed directly at the pathophysiological level. This review focuses on the diagnostic usefulness of synovial biopsies in the light of actual developments.

Using ultrasonography to facilitate best practice in diagnosis and management of RA

The key to successful management of rheumatoid arthritis (RA) is early objective quantification of inflammation and ongoing precise, tailored therapy to ensure long term suppression of inflammatory disease activity. Musculoskeletal ultrasonography (MSKUS) has emerged as a tool with the potential to enhance disease assessment and management in this area. This includes applications in patients with undifferentiated arthropathy attending an early inflammatory arthritis clinic, in which the diagnosis of inflammatory disease may be confirmed or refuted at an early stage, and those with treated RA where accurate measurement of outcomes, such as response to therapy, structural damage and disease remission, are extremely important. This imaging modality is safe and portable, making it ideal for outpatient and inpatient settings, and can be used to assess many joints in multiple planes and to demonstrate changes in disease activity and structural damage over time. MSKUS is gaining popularity among rheumatologists, as increasing evidence supports the added value of a physician-performed ultrasonography assessment above traditional clinical, laboratory and radiographic measures, enabling greater confidence in diagnostic and management decisions. Although additional longitudinal data are required and further applications are likely to arise, MSKUS may well possess the necessary attributes to facilitate best practice in inflammatory arthritis management.

Human cartilage glycoprotein 39--biomarker of joint damage in knee osteoarthritis

Human glycoprotein of cartilage (YKL-40) synthesizes chondrocytes and synovial cells in inflammatory conditions or remodels the outer cell matrix in osteoarthritis. The aim of this study was to conduct a parallel analysis between thickness of cartilage and length of osteophytes, ultrasound indicators of joint destruction, with levels of YKL-40 in serum in patients with primary osteoarthritis. Ultrasound findings and concentration of YKL-40(ng/ml) were examined in 88 patients. The average value cartilage thickness measured on medial condyles of the femur was 1.30 +/- 0.23 mm and on lateral was 1.39 +/- 0.27 mm. Median YKL-40 in patients with shorter osteophytes was 62.0 (44.5-90) ng/ml, and with longer osteophytes was 119 (range 80-171) ng/ml (p = 0.000). YKL-40 can be a marker for the appearance of longer osteophytes (sensitivity = 79.1%; specificity = 61.9%; cut off = 75.0 ng/ml). The duration of illness is very much connected to values of YKL-40 (r = 0.651, p = 0.000). After an illness duration of five years, the concentration of YKL-40 was 83.68 +/- 33.65 ng/ml, after ten years it was 138.22 +/- 48.88 ng/ml, and after 15 and 20 years it was 209.30 +/- 79.36 ng/ml and 218.50 +/- 106.51 ng/ml, respectively. Higher concentrations of YKL-40 indicate the level of cartilage destruction and can be used for assessment of destruction.

Comparison of in-office magnetic resonance imaging versus conventional radiography in detecting changes in erosions after one year of infliximab therapy in patients with rheumatoid arthritis

The objective of this study was to compare standard hand radiographs with in-office 0.2 T magnetic resonance imaging (MRI) in monitoring response to therapy in patients with rheumatoid arthritis (RA) who were receiving infliximab, to evaluate the frequency and location of erosions, and to determine if there were differences in outcome based on disease duration at baseline. Patients who satisfied the American College of Rheumatology criteria for RA and were receiving infliximab therapy were evaluated with a baseline and 1-year follow-up MRI. Magnetic resonance images were interpreted by two blinded, board-certified radiologists. Bone erosions were identified as well-defined defects extending through the cortical margin. The mean age of the 48 patients was 58.5 years. The median infliximab dosage was 4 mg/kg. Baseline data showed that 41 patients had abnormal MRIs. The mean time between the baseline and follow-up MRI examinations was 10.5 months. Follow-up MRI revealed regression in 11 patients. Thirty-one patients had both MRIs and radiographs. Magnetic resonance imaging was approximately twice as sensitive as radiography in detecting erosions at baseline. In-office MRI was useful in monitoring disease response after the initiation of infliximab treatment. Magnetic resonance imaging is potentially a very valuable diagnostic tool and prognostic indicator for use in patients with RA.

Advanced imaging in rheumatoid arthritis: part 2: erosions

Rheumatoid arthritis (RA) is a chronic and progressive inflammatory disorder primarily affecting the synovium. We now recognise that conventional radiographic images show changes of rheumatoid arthritis late after irreversible joint damage has occured. With the advent of powerful disease-modifying drugs there is a need for early demonstration of rheumatoid arthritis and to monitor progress of the disease and response to therapy. Advanced imaging techniques such as ultrasound and MRI have focussed on the demonstration and quantification of synovitis and erosions and allow early diagnosis of RA. The technology to quantify synovitis and erosions is developing rapidly and now allows change in disease activity to be assessed. However, problems undoubtedly exist in quantification techniques and this review serves to highlight them. Much of the literature on advanced imaging in RA appears in rheumatological journals and may not be familiar to radiologists. This review article aims to increase the awareness of radiologists to this field and to encourage them to participate and contribute to the ongoing development of these modalities. Without this collaboration it is unlikely that these modalities will reach their full potential in the field of rheumatological imaging. This review is in two parts. This first part addresses synovitis imaging. The second part will look at advanced imaging of erosions in RA.

Inflammation-induced bone loss: can it be prevented?

Inflammatory synovitis induces profound bone loss and OCLs are the instrument of this destruction. TNF blockers have an established role in the prevention of inflammatory bone loss in RA; however, not all patients respond to anti-TNF therapy and side effects may prevent long-term treatment in others. The B-cell--depleting antibody rituximab and the T-cell costimulation blocker abatacept are emerging as major treatment options for patients who are resistant to anti-TNF [96,97]. Proof-of-concept studies demonstrate that targeting RANK-mediated osteoclastogenesis prevents inflammatory bone loss and clinical application has only just begun. The efficacy of RANKL inhibition has been witnessed in trials of Denosumab, and RANKL-neutralizing antibodies are likely to become the treatment of choice for blocking RANKL in RA [77,78]. A major limitation of RANKL antagonism is that it does not treat synovitis. Therefore, anti-RANKL therapy most likely will be used in the context of MTX therapy. There is uncertainty about the possible extraskeletal adverse effects of long-term effects of long-term RANKL blockade. In particular, anti-RANKL therapy could jeopardize dendritic cell function or survival. The demonstrable role of OCLs in inflammation-induced bone loss also invites a reconsideration of the new BPs for bone protection [98]. Studies of ZA in preclinical models indicate that bone protection is comparable to that afforded by OPG. One possible caveat is that intravenous BPs are linked to jaw osteonecrosis [99], although the incidence is confined mainly to intensive treatment in the oncology setting. Although pulsed PTH stimulated bone formation in arthritic models, it has yet to be proven clinically in the context of powerful OCL inhibition with TNF or RANKL antagonists. With strategies that normalize OCL numbers, clinicians are poised to accomplish effective prevention of inflammation-induced bone loss.

Ultrasonography for rheumatologists: the development of specific competency based educational outcomes

BACKGROUND

A competency based approach to the education of rheumatologists in musculoskeletal ultrasonography (MSK US) ensures standards are documented, transparent, accountable, and defensible, with clear benefit to all stakeholders. Specific competency outcomes will facilitate informed development of a common curriculum and structured programme of training and assessment.

OBJECTIVE

To determine explicit competency based learning outcomes for rheumatologists undertaking MSK US.

METHODS

International experts in MSK US, satisfying specific selection criteria, were asked to define the minimum standards required by a rheumatologist to be judged competent in MSK US. They reviewed 115 MSK US skills, comprising bone and soft tissue pathology, in seven joints regions of the upper and lower limbs, and rated their relative importance according to specific criteria. These data are presented as specific educational outcomes within designated competency categories.

RESULTS

57 expert MSK US practitioners were identified and 35 took part in this study. Ten generic core competency outcomes were recognised including physics, anatomy, technique, and interpretation. Regarding specific regional competencies, 53% (61/115) were considered "must know" core learning outcomes, largely comprising inflammatory joint/tendon/bone pathology and guided procedures; 45% (52/115) were required at an intermediate/advanced level (18/115 "should know", 34/115 "could know"), and 2% (2/115) were deemed inappropriate/unnecessary for rheumatologist ultrasonographers.

CONCLUSIONS

This is the first study to developing a competency model for the education of rheumatologists in MSK US based on the evidence of international experts. A specific set of learning outcomes has been defined, which will facilitate future informed education and practice development and provide a blueprint for a structured rheumatology MSK US curriculum and assessment process.

Bone loss in inflammatory arthritis: mechanisms and therapeutic approaches with bisphosphonates

The inflammatory process in rheumatoid arthritis provokes intense bone resorption, evidenced as bone erosions, juxta-articular osteopenia and generalized osteoporosis. These types of bone loss share a common pathogenesis, and the role of osteoclasts in focal bone erosion was verified in elegant animal studies. The tumour necrosis factor (TNF) family of cytokines and receptors--specifically TNF-alpha, RANKL, RANK and OPG--are dominant regulators of osteoclastic bone resorption in rheumatoid arthritis. The confirmation of the osteoclast mechanism provides new insight into the structural joint protection afforded by disease-modifying drugs and suggests innovative approaches to limit bone destruction. Emerging treatment strategies for bone disease in rheumatoid arthritis are the use of monoclonal antibodies to neutralize RANKL, and powerful bisphosphonates that target pathogenic osteoclasts.

Ultrasound in rheumatology

Over the last decade, several studies have highlighted the value of ultrasonography for both clinical and research purposes in rheumatology. Ultrasonography is a non-invasive, inexpensive and free-of-radiation-hazards imaging technique providing quick and useful information for the management of rheumatic diseases. Considerable evidence supporting the role of ultrasonography in rheumatological clinical practice has led many rheumatologists to want to become experienced with this imaging technique. The main indications of ultrasonography in rheumatology include the evaluation of patients with regional pain syndromes and chronic arthritis, short-term therapy monitoring and guidance for invasive procedures. Ultrasonography's long learning curve is the main obstacle that hinders its widespread use in rheumatology. Many technical aspects may affect the scanning process and a correct interpretation of sonographic images depends on several elements such as a deep knowledge of ultrasonography anatomy and pathology.

Magnetic resonance imaging of peripheral joints in rheumatic diseases

The need for better methods than the conventional clinical, biochemical and radiographical examinations in the management of inflammatory joint diseases is evident, since these methods are not sensitive or specific to early pathologies and subtle changes. Magnetic resonance imaging (MRI) offers improved sensitivity to early inflammatory and destructive changes in peripheral joints in rheumatoid arthritis (RA) and, even though less well documented, in other inflammatory joint diseases. Good evidence is available that MRI bone erosions represent true bone abnormalities and are predictors of radiographical outcome in RA. Similarly, there is solid evidence for MRI synovitis representing true synovial inflammation and being of considerable practical, clinical and radiological significance in RA. Describing the encouraging current knowledge regarding MRI for diagnosis, monitoring and prognosis, this chapter discusses the potential for the use of MRI in the clinical management of patients with suspected and diagnosed inflammatory joint diseases, as well as research priorities and clinical situations where the use of MRI could be suggested.

Recommendations for musculoskeletal ultrasonography by rheumatologists: Setting global standards for best practice by expert consensus

OBJECTIVE

To establish an expert consensus of best practice for rheumatologists performing musculoskeletal ultrasonography (MUS).

METHODS

A panel of worldwide experts in MUS was identified by literature review, membership of teaching faculty, and peer recommendation. They were invited to take part in a 4-stage Delphi process employing 2 iterative rounds to establish a consensus of specific indications, anatomic areas, and knowledge and skills required by rheumatologists performing MUS.

RESULTS

Experts in MUS were identified (n = 57; 37 radiologists, 20 rheumatologists). Successive rounds of this rigorous Delphi exercise enabled group consensus to be achieved in 30 of the proposed 37 categories comprising 8 of 13 indications (inflammatory arthritis, tendon pathology, effusion, bursitis, monitoring disease activity, monitoring disease progression, guided aspiration, and injection), 8 of 10 anatomic areas (hand, wrist, elbow, shoulder, hip, knee, ankle and heel, and forefoot), and 14 categories of knowledge and skills (physics, anatomy, pathology, equipment, clinical application and relevance, indications and limitations, artifact, machine function and operation, patient and probe position, planes and system of examination, image optimization, dynamic assessment, color Doppler, and power Doppler).

CONCLUSION

We have produced the first expert-derived, interdisciplinary consensus of recommendations for rheumatologists performing MUS. This represents a significant advance that will not only direct future rheumatology MUS practice, but will facilitate informed educational development. This is an important step towards the introduction of a specific training curriculum and assessment process to ensure competent rheumatologist ultrasonographers.

New radiographic bone erosions in the wrists of patients with rheumatoid arthritis are detectable with magnetic resonance imaging a median of two years earlier

OBJECTIVE

In a 5-year followup study, we investigated the temporal relationship between development of wrist joint erosions as visualized by magnetic resonance imaging (MRI) versus conventional radiography (CR), in patients with rheumatoid arthritis. We also evaluated the risk of erosive progression on CR associated with the presence of MRI erosions.

METHODS

In 10 patients with rheumatoid arthritis, MRI and CR of the dominant wrist were performed annually for 5 years. In each image set, each wrist bone (metacarpal bases, carpal bones, radius, and ulna) was assessed for the absence or presence of bone erosions.

RESULTS

Nine bones showed radiographic erosions at baseline. Twenty-seven new radiographic erosions developed during the 5-year followup period. Of these 27 new erosions, 21 were detected 1-5 years earlier by MRI than by CR, 3 were simultaneously detected by both methods, 2 were detected 1-2 years later by MRI than by CR, and 1 erosion (radiographically detected at 5-year followup) was not visualized with MRI. MRI detection of new radiographic erosions preceded CR detection by a median of 2 years. In bones with MRI erosions at baseline, the relative risk of radiographic erosions at 5-year followup was 4.5 (95% confidence interval [95% CI] 2.6-7.6), compared with bones without baseline MRI erosions. If bones with baseline radiographic erosions were excluded from the analysis, the relative risk was 4.1 (95% CI 2.2-7.5).

CONCLUSION

Most new radiographic bone erosions (78%) were visualized at least 1 year earlier by MRI than by CR. This illustrates that the information on joint destruction provided by CR is considerably delayed compared with that provided by MRI. A significantly increased risk of progression of radiographic erosion in bones with baseline MRI erosions was observed, demonstrating a prognostic value of MRI with respect to long-term radiographic outcome.

Classification of rheumatoid joint inflammation based on laser imaging

We describe a classification system for a novel imaging method for arthritic finger joints. The basis of this system is a laser imaging technique which is sensitive to the optical characteristics of finger joint tissue. From the laser images acquired at baseline and follow-up, finger joints can automatically be classified according to whether the inflammatory status has improved or worsened. To perform the classification task, various linear and kernel-based systems were implemented and their performances were compared. Based on the results presented in this paper, we conclude that the laser-based imaging permits a reliable classification of pathological finger joints, making it a sensitive method for detecting arthritic changes.

Ultrasonography in inflammatory joint disease: why should rheumatologists pay attention?

During the last decade, articular ultrasonography (US) has been found effective in evaluating inflammatory, degenerative, and traumatic abnormalities of articular and periarticular tissues. In clinical practice, US used in combination with a thorough clinical evaluation can help rheumatologists to confirm or to refute diagnostic hypotheses. US is safer than computed tomography (CT), an advantage shared by magnetic resonance imaging (MRI). As compared to CT and MRI, US is less expensive; in addition, it can be performed immediately, for several joints, as often as needed. Furthermore, US allows dynamic studies. Several articles published in rheumatology journals emphasize the value of US in patients with musculoskeletal diseases. The present review article discusses the indications, efficacy, and limitations of articular US.

Magnetic resonance imaging: opportunities for rheumatoid arthritis disease assessment and monitoring long-term treatment outcomes

Early diagnosis of rheumatoid arthritis (RA) combined with early initiation of an appropriate treatment regimen is acknowledged as an important factor in improving clinical outcomes in patients with RA. Early diagnosis allows treatment intervention to occur sooner in order to inhibit the progression of structural joint damage as well as providing improved patient quality of life. Unfortunately, early diagnosis has been challenging due to the non-specific signs and symptoms associated with many polyarthropathies and the lack of accurate definitive diagnostic tests that can accurately classify RA at presentation. The emphasis on early diagnosis has fueled the need for powerful, sensitive, non-invasive imaging techniques that not only accurately define RA and give an indication of prognosis, but can also serve as a tool to monitor long-term treatment outcomes. This article reviews the potential uses of magnetic resonance imaging as a tool for the classification, documentation, and clinical monitoring of RA.

The relationship between soft tissue swelling, joint space narrowing and erosive damage in hand X-rays of patients with rheumatoid arthritis

OBJECTIVES

To test the hypotheses that the progression of joint space narrowing behaves differently from the progression of erosions and that clinically and radiologically assessed soft tissue swelling relates more to diffuse cartilage loss than to erosive damage.

METHODS

Radiographs and clinical data were obtained from 28 patients in a prospective, multicentre, randomized, placebo-controlled trial of prednisolone 7.5 mg daily over 2 yr. Radiographic scoring included the Larsen score, joint space narrowing and soft tissue swelling. Clinical joint inflammation in the hands was assessed every 3 months and cumulative synovitis score over the period of study was then calculated for each joint. The placebo-treated patients and the prednisolone-treated patients were analysed separately. The Larsen scores were compared after log transformation [transformed score=log(10) (original score+1)]. Changes in Larsen scores and joint space narrowing scores were compared with the cumulative presence of clinical synovitis and radiological soft tissue swelling using the correlation coefficient.

RESULTS

There was a difference in the rate of progression in the Larsen score between placebo- and prednisolone-treated patients, but there was no significant difference in the rate of joint space loss. In placebo-treated patients, measures of synovitis correlated more strongly with progression of joint space narrowing than with changes in the Larsen score. In prednisolone-treated patients there was no correlation between clinical synovitis and change in Larsen score (r=0.029) and only a slight and non-significant correlation with joint space narrowing (r=0.127). Radiographic evidence of soft tissue swelling remained correlated with joint space narrowing (r=0.279, P:<0.001) but was not correlated with change in Larsen score (r=-0.113, P:<0.001 for difference between correlations). The correlation between Larsen score progression and joint space narrowing seen in the non-treated patients was completely abolished in the glucocorticoid-treated group (r=-0.003).

CONCLUSIONS

The progression of joint space narrowing behaves differently from the progression of erosions. Prednisolone slows (or even stops) the progression of erosions (as assessed by the Larsen score) while making no difference to the progression of cartilage loss (as assessed by joint space narrowing). The results also suggest that synovitis, whether measured clinically or radiologically, is more closely related to diffuse cartilage loss than to erosion progression. Any link between synovitis and erosions is abolished by glucocorticoid therapy while the link between synovitis and cartilage loss is not, pointing to at least two different mechanisms for these observed radiological features.

Ultrasonography in the evaluation of bone erosions

OBJECTIVE

To demonstrate the diagnostic efficacy of ultrasonography in depicting erosions in patients with rheumatoid arthritis and to compare sonographic and radiographic findings.

METHODS

Sonographic images were obtained with an AU-4 Idea Esaote Biomedica (Genoa, Italy) equipped with a 13 MHz linear transducer.

RESULTS

The images reported in this essay are representative examples of the ability of ultrasonography to detect and characterise even minimal bone margin changes in rheumatoid arthritis.

CONCLUSION

Ultrasonography with very high frequency transducers can depict bone erosions in early target areas of bone resorption. However, further studies are needed to validate this technique and to evaluate the relation between sonographic findings and those obtained with other imaging techniques (standard radiology, magnetic resonance).

What practical skills do rheumatologists of the future need?

In this chapter, we consider future practical skills required for rheumatologists. While difficult to predict against a background of rapid technological advance and successive changes to health-care provision world wide, a number of questions are examined. The first question is what core skills are essential in the curriculum? This has been addressed in at least one joint European effort by UEMS. Great diversity in both clinical practice and training was found across Europe; clearly, the difference across continents may prove even more significant. Second, the role of arthroscopy is considered, the evidence for its therapeutic benefit in clinical rheumatology practice being inconclusive. Issues concerning diagnostic methods including electrophysiology and ultrasound (US) are also discussed in this chapter. There is evidence to support the use of electrophysiology in routine diagnosis for specific diseases. US has become popular as technology improves. It is cheap but highly operator dependent, and the feasibility of rheumatologists using US in the clinic remains to be proved. In conclusion, health care is changing rapidly, and training must adapt, and is adapting, to meet its challenges. A number of opportunities will present to the rheumatologist of the future, but the feasibility of these in routine clinical practice remains to be seen.

The value of sonography in the detection of bone erosions in patients with rheumatoid arthritis: a comparison with conventional radiography

OBJECTIVE

The ability to make an early, accurate diagnosis of rheumatoid arthritis (RA) has become increasingly important with the availability of new, expensive, and targeted therapies. However, plain radiography, the traditional method of detecting the characteristic bone erosions and an important adjunct in establishing a diagnosis of RA, is known to be insensitive. This study compared sonography, a modern imaging technique, with conventional radiography for the detection of erosions in the metacarpophalangeal (MCP) joints of patients with RA.

METHODS

One hundred RA patients (including 40 with early disease) underwent posteroanterior radiography and sonography of the MCP joints of the dominant hand. Twenty asymptomatic control subjects also underwent sonography. Erosion sites were recorded and subsequently compared using each modality. Magnetic resonance imaging (MRI) was performed on the second MCP joint in 25 patients with early RA to confirm the pathologic specificity of sonographic erosions. Intraobserver reliability of sonography readings was assessed using video recordings of 55 MCP joint scans of RA patients, and interobserver reliability was assessed by comparing 160 MCP joint scans performed sequentially by 2 independent observers.

RESULTS

Sonography detected 127 definite erosions in 56 of 100 RA patients, compared with radiographic detection of 32 erosions (26 [81%] of which coincided with sonographic erosions) in 17 of 100 patients (P < 0.0001). In early disease, sonography detected 6.5-fold more erosions than did radiography, in 7.5-fold the number of patients. In late disease, these differences were 3.4-fold and 2.7-fold, respectively. On MRI, all sonographic erosions not visible on radiography (n = 12) corresponded by site to MRI abnormalities. The Cohen-kappa values for intra- and interobserver reliability of sonography were 0.75 and 0.76, respectively.

CONCLUSION

Sonography is a reliable technique that detects more erosions than radiography, especially in early RA. Sonographic erosions not seen on radiography corresponded to MRI bone abnormalities. This technology has potential in the management of patients with early RA/inflammatory arthritis and is likely to have major implications for the future practice of rheumatology.

Ultrasound in inflammatory disease

US may be used effectively to diagnose and treat a wide range of musculoskeletal inflammatory conditions. It is likely that its usage will increase with regards to such conditions especially in the management of rheumatology clinic patients.