TOPLINE

Patients with hand osteoarthritis (OA) who had synovitis on baseline ultrasonography or MRI had increased odds of radiographic worsening in the first carpometacarpal (CMC1) joint at the thumb base and interphalangeal joints.

METHODOLOGY

• In a prospective observational study (Nor-Hand), researchers assessed whether synovitis observed on ultrasonography or MRI at the CMC1 and interphalangeal joints was associated with subsequent radiographic progression in hand OA.
• The final analysis included 201 adults aged 40-70 years with hand OA (median age, 60.8 years; 86.6% women). Baseline visits occurred in 2016-2017, and follow-up radiographs were obtained in 2019-2021.
• At baseline, most patients underwent bilateral ultrasonography of the CMC1 and interphalangeal joints, contrast-enhanced MRI of the dominant hand, and standardized hand radiography. Synovitis was graded on a 0-3 scale on ultrasonography and MRI.
• At follow-up, researchers assessed radiographic progression, defined as an increase of at least one Kellgren-Lawrence (KL) grade, an increase of at least one osteophyte or joint-space narrowing grade, or the appearance of new erosions on radiographs.
• Associations between higher grades of synovitis at baseline and subsequent progression were evaluated after adjustment for factors such as age, sex, BMI, and follow-up time, while accounting for multiple joints per patient.

TAKEAWAY

• Over a mean follow-up duration of 3.4 years, radiographic worsening by at least one KL grade occurred in 14.7% of the CMC1 joints and 10.2% of the interphalangeal joints.
• All grades of gray-scale synovitis at baseline were associated with increased odds of KL progression in both joint groups, with the highest odds of progression observed at grade 3 — 9.3-fold in CMC1 joints and 23.4-fold in interphalangeal joints (P < .05 for both).
• In interphalangeal joints, higher grades of power Doppler activity were associated with 4.1- to 16.2-fold increased odds of KL progression (P < .05 for all grades). In CMC1 joints, the associations were significant for grades 1 and 2 but not grade 3.
• MRI-detected synovitis (grades 2-3) was associated with increased odds of radiographic progression in both joint groups (P < .05 for all) and increased odds of new erosions in interphalangeal joints (P < .05). No CMC1 joints developed erosions.

IN PRACTICE

"[The] findings support inflammation as a relevant mechanism across hand OA phenotypes," the authors of the study wrote.

SOURCE

The study was led by Lovisa Klingenberg of Diakonhjemmet Hospital in Oslo, Norway. It was published online on August 20, 2026, in RMD Open.

LIMITATIONS

The study lacked a formal calculation for sample size. The small number of CMC1 joints may have reduced the statistical power and precision of estimates for severe grades of synovitis. Patients were recruited from secondary care only.

DISCLOSURES

The Nor-Hand study received funding from multiple sources, including an award grant from Pfizer/Lilly, the South-Eastern Norway Regional Health Authority, and the Dr. Trygve Gythfeldt and Wife Research Foundation; the study center received funding from the Research Council of Norway. One author reported receiving personal fees and honoraria from multiple pharmaceutical companies outside of the submitted work. Another author reported receiving honoraria and advisory board fees from companies, including Lilly, outside the submitted work.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.