I would like to thank the ORA for providing me the opportunity to attend the ACR Conference and Advanced MSK Ultrasound (MSKUS) Course in Atlanta. As usual, the conference was packed with highlights of recent advances across the spectrum of rheumatology.
Given my interest (and fellowship) in MSKUS, my principal goal during the course was to learn advanced skills and techniques. During the meeting, I attended sessions and posters that discussed how MSKUS was being used in an evidence-based manner in other countries to improve care, which could potentially be translated locally.
MSKUS Advanced Course:
The course had sessions from world-renowned experts with ample hands-on time, covering topics on tendons, enthesitis, inflammatory arthritis, and crystal arthropathies.
Some of the key learnings for me were:
1. Bedside MSKSUS is useful in detecting findings that are either not looked at, or missed, during formal ultrasound studies. One such finding is paratenonitis, which is often very useful in identifying early psoriatic arthritis [1].
2. Enthesitis is frequently the only manifestation of spondyloarthropathies in early disease [2] and may be a marker of more severe disease [3]. Our current clinical definition of enthesitis is clearly lacking, and often does not differentiate from fibromyalgia and mechanical pain. I was able to learn ultrasonographic techniques for identifying enthesopathy and practice them on patients during the hands-on session. We also reviewed various scoring systems that are being deliberated (OMERACT vs GRAPPA) and their roles in diagnosis or treatment response.
3. With respect to RA, MSKUS is a well-known diagnostic tool to improve certainty of diagnosis and identify subclinical disease [4]. However, its use as an outcome measure is less clear due to many published scoring systems and a lack of standardization in data collection and image reading. We spent time reviewing the most popular semiquantitative scoring system (EULAROMERACT) and used our hands-on time to practice scoring synovitis with the grading scales [5].
4. Crystal arthritis, as we all know, can mimic other arthropathies. Unfortunately, joint aspiration in gout is successful only 50% of the time and correct identification of MSU crystals in the lab ranges from 43-79% [6-7]. We went over common U/S findings of BCP, CPPD and gout crystal arthropathies. The focus was on identifying early erosions and specific signs such as ‘double contour’, ‘rim sign’, and ‘snowstorm sign’. I was surprised to learn that U/S was much better than radiography (67% vs 28%) at catching erosions in patients with gout [8], making it more useful in early detection of erosive joint damage/tophaceous deposits in clinically silent joints.
This has the potential to change management and outcomes. Even the 2015 ACR-EULAR criteria recommends imaging with U/S as it significantly improves the sensitivity and specificity of diagnosis [9].
Meeting take home points:
The meeting had several sessions/posters that piqued my interest, covering areas of MSKUS in education and diagnoses such as Sjogren’s, myositis, and vasculitis.
1. Ultrasound training has been integrated into undergraduate medical training (62% of American medical schools) [10] and has been shown to improve learning and examination scores [11]. Although there is a push towards point-of-care U/S (POCUS) in residency, several barriers continue to exist; lack of U/S trained faculty, cost and lack of equipment, and no systematic curriculum. Several American programs have implemented formal MSKUS curriculums to teach basic knowledge and skills to medical students and residents. This has also shown to increase interest in rheumatology as a field and potentially address workforce issues, especially since other specialties have already integrated POCUS in their practices (i.e. Cardiology, Respirology, GIM). I think we have similar barriers locally, and model programs in the US can be used to implement similar curriculums, as we seem to be years behind the Americans and Europeans in this field.
2. Dr. Aldayba from Johns Hopkins discussed the use of U/S as a diagnostic tool in inflammatory myositis, and its role as a complementary/alternative modality to MRI. There is emerging evidence that increased muscle echointensity can be diagnostic of disease. This is useful in areas where there is no easy access to MRI or in patients who do not have classical presentations/normal CK. However, the role of U/S for muscle evaluation still needs to be fully optimized.
3. Drs. Bruyn and Jousee-Joulin discussed the current limitations of salivary gland assessment in Sjogren’s and how U/S has been recently shown to have excellent diagnostic accuracy. It can be used to assess structural abnormalities (hypoechoic areas, hyperechoic bands) and disease activity (vacuolization). Although it is versatile, quick and non-invasive (compared to biopsy), it is highly operator dependent. This makes appropriate training incredibly important.
4. Fast track clinics (FTC) in Europe have reduced the time to evaluation and definitive diagnosis of GCA, with vascular ultrasound replacing temporal artery biopsy (TAB) in select cases. Although the gold standard is TAB, it does not detect extracranial vasculitis and has false negatives, and that is where U/S has added value as it looks at more areas. EULAR recommends using vascular U/S to diagnose/rule-out GCA in high and low clinical suspicion without a TAB. Interestingly, the new ACR guidelines presented at the meeting conditionally recommended TAB over ultrasound due to limited expertise in North America compared to Europe. They suggest it may be more widely used if expertise increases. There were several posters looking at FTC in the USA, and one Seattle group (Abstract 2690) showed that vascular U/S done by sonographers improved the detection rate of GCA over just TAB [12]. Such FTC can be conceivably implemented in larger centres in Ontario, providing a resource to those who cannot access biopsy and potentially detect cases missed by TAB. However, it will require rheumatologists to gain expertise and validate their skill against TAB to show similar sensitivity and specificity.
Overall, the course and meeting were very useful in adding to my MSKUS skillset and learning about its use internationally in providing rheumatological care. Point of care ultrasound is quickly becoming the modern physician’s stethoscope – a bedside tool that can look at potentially any organ, provide immediate and objective data, and real-time guidance for procedures with better outcomes.
1. Gutierrez M, et al., Ann Rheum Dis 2011;70:1111-4
2. D’Agostino MA, et al. Best Prac Res Clin Rheum 2006;20:473-86
3. Polachek A, et al. Arthritis Rheumatol 2016;68:(suppl 10)
4. Colebatch AN, et al. Ann Rheum Dis 2013;72:804-14
5. D’Agostino MA, et al. RMD Open 2017;3:e000428
6. Gordon C, et al. Ann Rheum Dis 1989;48:737-42
7. McGill NW, et al. Aus NZ J Med 1991;21:710-713
8. Wright SA, et al. Ann Rheum Dis 2007;66:859-64
9. Neogi T, et al. Ann Rheum Dis 2015;74:1789-1798
10. Bahner DP, et al. Acad Med 2014;89:1681-6
11. Dinh VA, et al. J Ultrasound Med 2015;34:43-50
12. Sacksen I, et al. Arthritis Rheumatol 2019;71:(suppl 10)
