10 Reasons We Might Want a Musculoskeletal Ultrasound (MSUS) of a Joint
Back in 2009, dozens of phone calls revealed no one in our area who could perform a musculoskeletal ultrasound (MSUS). Today, worried about my son, I made calls again to orthopedists and hospitals. When I called the top medical centers in our region, I found one ultrasound technologist who had heard of MSUS and she knew of no one who performs it yet. She agreed that there’s a great need for it, but some others I talked to asked, “Why would you want an ultrasound of a joint?” So I thought I’d write a post to answer that question.
Thousands of comments on this blog lament the inability of physicians to see and know with certainty the disease activity of their patients. This problem is particularly weighty when we read of how critical early diagnosis and treatment are for this disease to be “controlled.” Musculoskeletal ultrasound (MSUS) is one way to see what’s going on inside joints, one obvious focus of rheumatoid disease activity.
Two Boston doctors wrote a great overview of (MSUS) for the Journal of Musculoskeletal Medicine. They review numerous studies of MSUS, including one which shows that clinical evaluations and disease management plans were each altered 53% of the time after a MSUS in rheumatology patients. A clear reason: “MSUS is more sensitive than other modalities in assessing disease activity; as previously described, positive power Doppler signal in synovial sites has corresponded with histological evidence of vascularity, a marker for inflammation.”
Specific advantages of musculoskeletal ultrasound (MSUS) in rheumatology
- MSUS is much more sensitive to examine synovial tissue than clinical examinations.
- MSUS allows dynamic assessment. That means you can change the position of the joint or even evaluate it during movement which may make abnormality more obvious. Motion can be both active and passive, allowing examiners to learn more.
- MSUS is better for evaluating certain joints. “Because it is multiplanar, US is 3 or 4 times more sensitive than plain radiography for detecting erosions in the metacarpophalangeal (MCP) joints and metatarsophalangeal joints of patients with rheumatoid arthritis (RA), especially the second and fifth MCP joints, which are more accessible to US.”
- MSUS is done without radiation.
- Patients can guide the examiner by describing pain.
- Numerous joints can be examined; you don’t usually get MRI’s of multiple joints.
- No waiting is needed if there is MSUS equipment in the office.
- Other advantages to MSUS over MRI include comfort…
- and cost.
However, the great disadvantage of MSUS is its extreme user-dependency. I’ve read that in articles and been told that by several doctors I’ve interviewed. Sadly, we also learned about this first hand. If that disadvantage can be overcome by training, MSUS will be of great value to patients who need to obtain early and accurate diagnosis and treatments.
- Three-part blog post series on musculoskeletal ultrasound.
- A Paradigm Shift in Rheumatoid Arthritis Disease Activity? Part 2
- Does It Matter Whether Rheumatoid Arthritis Affects DIP Joints?
- Rheumatoid Arthritis Swelling, Take Two
- Click here to see the SonoSite ultrasound video on the sexy post
NOTE: Your comments are an important resource for future readers of this post in the months to come. Please find the comment link below each post.Kelly Young. All rights reserved.