Wrist Arthritis: AI-Powered Imaging Analysis

For degenerative wrist arthritis, the Mayo Clinic classification grades radiocarpal osteoarthritis on a four-point scale: Grade I shows subchondral sclerosis without joint space loss, Grade II demonstrates moderate joint space narrowing, Grade III shows severe narrowing with bone-on-bone contact, and Grade IV includes bony collapse or advanced carpal malalignment. SLAC and SNAC arthritis are staged separately by compartment involvement. Inflammatory arthritis severity is assessed by erosion depth, joint space loss, and synovial proliferation on MRI. Our AI applies the appropriate grading system based on the pattern identified.

Scapholunate advanced collapse (SLAC) originates from chronic scapholunate ligament injury with the arthrosis beginning at the radial styloid-scaphoid articulation and progressing to the entire radioscaphoid and then midcarpal joint while the radiolunate joint is preserved. Scaphoid nonunion advanced collapse (SNAC) results from a chronic scaphoid fracture nonunion with a similar progression pattern but starting at the distal scaphoid-radius articulation. The distinction lies in whether a scapholunate gap or a scaphoid fracture nonunion is identified as the inciting lesion. Our AI differentiates these patterns because the surgical implications differ significantly.

Plain radiographs reveal established joint space narrowing, osteophytes, subchondral sclerosis, and cysts but underestimate early cartilage loss. MRI directly visualizes cartilage thinning, bone marrow edema indicating active subchondral stress, synovial proliferation, and ligamentous contributions to the arthritis pattern. In inflammatory arthritis, gadolinium-enhanced MRI detects early synovitis and erosions before radiographic changes appear, enabling earlier disease-modifying treatment. Our AI evaluates cartilage signal, synovial volume, and erosive changes across all wrist compartments to characterize disease severity and activity.