Rheumatoid Arthritis: Replacement of the Metacarpophalangeal Joint Is Beneficial
Most patients with rheumatoid arthritis suffer from synovitis that involves small joints of the hands. It’s not a coincidence that classification criteria for RA are based on this fact [2,3]. With the progression of the disease rheumatoid arthritis can cause deformities and eventually disability.
The end result of arthritis of the metacarpophalangeal (MCP) joints is ulnar drift, subluxation of extensor tendons, and palmar subluxation of joints. The most common surgical treatment options for these conditions are synovectomy, extensor mechanism relocation, intrinsic tendon release, arthroplasty.
Recent study showed that after seven years of follow-up, metacarpophalangeal arthroplasty using a silicone implant (Silicone Metacarpophalangeal Joint Arthroplasty or SMPA) has resulted in improved function and reduced deformities of the fingers compared to no surgery
Key results
- Non-SMPA patients had better MHQ (Michigan Hand Outcomes Questionnaire) scores at baseline but the surgical subjects had improved scores over time. Most patients who have not undergone a SMPA retained their function of the hand during monitoring.
- SMPA group: At the seven-year follow-up visit, a significant improvement was observed in ulnar drift, extensor lag and MCP joint arc of motion in the SMPA group. was recorded for the group that is the subject of a SMPA.
- No significant improvements in grip or pinch strength were observed in either group.
Study Design
- The SARA study (Silicone Arthroplasty in Rheumatoid Arthritis) is a prospective cohort study of 73 patients having undergone a SMPA and 97 patients without Patients were recruited from three centers.
- Patients were evaluated at baseline, at the sixth month and annually for seven years.
- Funding: National Institutes of Health (NIH).
- Michigan Hand Outcomes Questionnaire (MHQ), Arthritis Impact Measurement Scales (AIMS2), and functional measures (grip/pinch strength, Jebson-Taylor test, and ulnar drift, extensor lag and arc of motion measurements at the metacarpophalangeal (MCP) joints assess the ability to perform daily living activities.
To remember
The largest prospective study to date on the metacarpophalangeal joint arthroplasty using silicone implant with follow-up of seven years, found that the procedure has resulted in improved function and reduced deformaties of the fingers compared to no surgery.
Why is this important?
Most patients with rheumatoid arthritis have synovitis of the MCP joints that could worsen and cause disability.
Reference
- Chung, Kevin C., et al. "Seven Year Outcomes of the Silicone Arthroplasty in Rheumatoid Arthritis (SARA) Study." Journal of Hand Surgery 41.9 (2016): S6.
- Arnett et al. The American Rheumatism Association 1987 revised criteria for the classification of rheumatoid arthritis. Arthritis Rheum 1988;31:315-324
- Aletaha, Daniel, et al. "2010 rheumatoid arthritis classification criteria: an American College of Rheumatology/European League Against Rheumatism collaborative initiative." Arthritis & Rheumatism 62.9 (2010): 2569-2581.
Tags: rheumatoid arthritis, surgery, MCP