Symptomatic and asymptomatic interphalageal osteoarthritis: An ultrasonographic study

To date few studies have examined whether ultrasonography can depict morphologic differences in painful and painless osteoarthritis (OA). This study describes and compares the clinical, radiographic and ultrasonographic findings of patients with both painful and painless proximal interphalgeal (PIP) and/or distal interphalgeal (DIP) OA.

Patients with PIP and/or DIP OA (ACR criteria) were prospectively recruited. The clinical rheumatologist chose up to 3 painful joints and up to 3 painless symmetric joints in each patient to define 2 cohorts of OA: symptomatic (SG) and asymptomatic (ASG). A conventional postero-anterior hand x ray was performed and read by one rheumatologist following the OARSI atlas, blinded to clinical and sonographic data. Ultrasound (US) was performed by an experienced rheumatologist, blinded to both clinical and radiographic data in joints previously selected by the clinical rheumatologist. US-pathology was assessed as present or absent as defined in previous reports: osteophytes, joint space narrowing, synovitis, intra-articular power doppler signal, intra-articular bony erosion, and visualization of cartilage. Radiographic and ultrasonographic intrareader reliability test was performed.

A total of 50 joints in the SG and ASG were included from 20 right handed women aged 61.85 (46-73) years with PIP and DIP OA diagnosed 6.8 (1-17) years ago. 70% SG joints and ASG were right and left sided respectively. The SG showed significantly more osteophytes, synovitis and non-visualization of joint cartilage. Intrareader radiographic and ultrasonographic agreement was excellent.

This study demonstrates that painful PIP and/or DIP OA have more ultrasonographic structural changes and synovitis.