As more rheumatologists catch the musculoskeletal ultrasound (MSUS) wave, the American College of Rheumatology (ACR) has been steadfast in their mission to determine best practices for the equipment if it were to be placed in qualified offices nationwide.

With an estimated 50 million Americans suffering from arthritis, while 7 million others are saddled with inflammatory rheumatic diseases such as systemic lupus erythematosus, rheumatoid arthritis and gout, MSUS availability at the prognostic/diagnostic onset would certainly come in handy.

“Musculoskeletal ultrasound is a non-invasive, safe, imaging technology that can easily be deployed at the point of care by rheumatologists and actually, other professionals,” lead researcher for the guidelines, Tim McAlindon, MD, from Tufts Medical Center in Boston, told PhysBizTech. “We evaluated its use in the context of a rheumatological assessment; we assumed that the operators were qualified in its use and that they’re using contemporary equipment. With those predicates we did an extensive literature review to determine whether it’s reasonable to recommend that rheumatologists use this technology.”

McAlindon and the rest of the ACR task force appraised scores of medical literature to form the guidelines of use for MSUS tools in rheumatology practices. The ACR outlined the recommendation classification and methodology as such: “These recommendations include a rating by type of evidence, with Level A supported by at least two randomized clinical trials or one or more meta-analyses of randomized trials; Level B backed by one randomized trial, non-randomized studies or meta-analyses of non-randomized studies; and Level C confirmed by consensus expert opinion, case studies, or standard clinical care.”

The task force was able to identify a number of pathological scenarios where MSUS use would prove especially beneficial. 

“It’s clear that ultrasonography can easily detect many of the chemical features that we’re looking for in examination, including in situations where it’s not clinically evident from a simple clinical exam,” McAlindon said. “The sort pathologies for which this is most evident include things like effusions, inflammation in structures around the joint, deposition of crystals like uric acid crystals and various calcium crystals and other related pathologies. There are many, many reports documenting this and there is also quite high-level evidence in relation to its use for guiding the sort of procedure that rheumatologists do in their clinics, such as injecting and aspirating joints. For example, it’s been shown that use of ultrasounds improves the precision of injection placement for injecting into joints. You can use the DOPLA component of ultrasonography to detect blood flow and inflammation. Ultrasound can detect inflammation in joints before it’s even clinically apparent and at sites where you may not suspect it. All of those can contribute to diagnostic information, prognostic information and decision-making regarding a treatment plan.”

A partial list of the 14 ACR recommendations includes:

• For a patient with articular pain, swelling or mechanical symptoms, without definitive diagnosis on clinical exam, it is reasonable to use MSUS to further elucidate the diagnosis at the following joints: glenohumeral, acromioclavicular, sternoclavicular, elbow, wrist, metacarpophalangeal, interphalangeal, hip, knee, ankle, midfoot and metatarsophalangeal. Level of evidence: B.
• For a patient with diagnosed inflammatory arthritis and new or ongoing symptoms without definitive diagnosis on clinical exam, it is reasonable to use MSUS to evaluate for inflammatory disease activity, structural damage or emergence of an alternate cause at the following sites: glenohumeral, acromioclavicular, elbow, wrist, metacarpophalangeal, interphalangeal, hip, knee, ankle, midfoot and metatarsophalangeal, and entheseal. Level B.
• For a patient with shoulder pain or mechanical symptoms, without definitive diagnosis on clinical exam, it is reasonable to use MSUS to evaluate underlying structural disorders; but not for adhesive capsulitis or as preparation for surgical intervention. Level B.
• It is reasonable to use MSUS to evaluate the parotid and submandibular glands in a patient being evaluated for Sjögren's disease to determine whether they have typical changes as further evidence of the disorder. Level B.
• For a patient with symptoms in the region of a joint whose evaluation is obfuscated by adipose or other local derangements of soft tissue, it is reasonable to use MSUS to facilitate clinical assessment at the glenohumeral, acromioclavicular, elbow, wrist, hand, metacarpophalangeal, interphalangeal, hip, knee, ankle/foot, and metatarsophalangeal joints. Level C.
• For a patient with regional neuropathic pain without definitive diagnosis on clinical exam, it is reasonable to use MSUS to diagnose entrapment of the median nerve at the carpal tunnel; ulnar nerve at the cubital tunnel; and posterior tibial nerve at the tarsal tunnel. Level B.
• It is reasonable to use MSUS to guide articular and peri-articular aspiration or injection at sites that include the synovial, tenosynovial, bursal, peritendinous and perientheseal areas. Level A.

There were certain situations, the task force discovered, where MSUS usage would not be appropriate — the evaluation of temple arteries being the sole case mentioned by McAlindon. The lack of evidence regarding the machine’s cost-effectiveness also gave the task force pause about fully mandating implementation of MSUS.

“Most of these studies are somewhat descriptive, they don’t deal with the economics; there have been few cost-effectiveness evaluations. So we can certainly talk about its utility and it’s ability to image all of these pathologies, but we don’t have very direct comparisons as to how it performs next to what traditionally rheumatologists are doing…For that reason, we talk about reasonableness rather than appropriateness [in the recommendations] and I think that we can conclude that although it’s reasonable in many scenarios, we need more studies to evaluate its cost-effectiveness. We think it’s reasonable to do this [use MSUS technology], but we certainly wouldn’t mandate it.” McAlindon noted.

Although further study is needed, McAlindon did suggest that incorporating the technology into rheumatologist training programs would be advantageous.

“Some of the things that we should consider [in the aftermath of the report] include developing a kind of certification program for rheumatologists specifically, figuring out how to integrate this into our current training programs and probably some work on cost-effectiveness,” he said. “There are some independent efforts to produce training programs, some bodes are doing this already, and so it may not be that difficult to incorporate those more broadly. I don’t think it has to be that far off.”

The full recommendations list can be found here, in the current online edition of Arthritis Care & Research.