Imaging modalities in hand osteoarthritis--and perspectives of conventional radiography, magnetic resonance imaging, and ultrasonography

Abstract

Hand osteoarthritis (OA) is very frequent in middle-aged and older women and men in the general population. Currently, owing to high feasibility and low costs, conventional radiography (CR) is the method of choice for evaluation of hand OA. CR provides a two-dimensional picture of bony changes, such as osteophytes, erosions, cysts, and sclerosis, and joint space narrowing as an indirect measure of cartilage loss. There are several standardized scoring methods for evaluation of radiographic hand OA. The scales have shown similar reliability, validity, and sensitivity to change, and no conclusion about the preferred instrument has been drawn. Patients with hand OA may experience pain, stiffness, and physical disability, but the associations between radiographic findings and clinical symptoms are weak to moderate and vary across studies. OA is, indeed, recognized to involve the whole joint, and modern imaging techniques such as ultrasound (US) and magnetic resonance imaging (MRI) could be valuable tools for better evaluation of hand OA. Standardized scoring methods have been proposed for both modalities. Several studies have examined the validity of US features in hand OA, whereas knowledge of the validity of MRI is more limited. However, both synovitis (detected by either US or MRI) and MRI-defined bone marrow lesions have been associated with pain, indicating that treatment of inflammation is important for pain management in hand OA. Both US and MRI have shown better sensitivity than CR in detection of erosions, and this may indicate that erosive hand OA may be more common than previously thought.

Figure 1

Conventional radiography (CR) and magnetic resonance imaging (MRI) (coronal/axial T1-weighted fat-suppressed images) of the right hand. Both CR (a) and MRI (b,c) show severe osteoarthritis with osteophytes (white arrowheads) and central collapse of the joint plate in the 2nd distal interphalangeal (DIP) joint. Both MRI and CR show severe joint space narrowing in the 3rd DIP joint. The osteophytes are more easily seen on CR, whereas MRI shows the collateral ligaments (black arrowheads). CR shows a cyst-like lesion (white arrow), which on MRI seems to be an erosion (that is, a cortical break in the axial plane).

Figure 2

Ultrasonography of the 2nd proximal interphalageal joint. The joint is visualized in sagittal (a,c) and axial (b,d) scans. In a gray-scale image (a), proximal and distal osteophytes are visible (arrows). Gray-scale synovitis is visible in both sagittal (a) and axial (b) planes (arrowheads). Power Doppler signal is visible in (c) and (d).