Osteoarthritis and subluxation due to untreated Scaphoid non-union/ scapholunate ligament injury
Causes:
Commenest - scapholunate dissociation with rotatory subluxation of scaphoid
Scaphoid nonunion advanced collapse (SNAC)
AVN scaphoid
Midcarpal instability
Intra-articular fractures involving radius, sscaphoid, capitate, lunate
Kienbock disease
OA with scapholunate dissociation
capitolunate degeneration
Inflammatory arthritis - CPPD
Pathophisiology:
Involvement of radioscaphoid joint. Radiolunate joint is not involved
Progression:
Radioscaphoid joint involvement - narrowing of radioscaphoid joint at radial styloid aspect; x-ray shows elongation on the radial styloid
Destruction of radioscaphoid joint with involvement of entire scaphoid fossa, leading to posterolateral position of capitate
Capitolunate joint involvement - capitolunate joint cartilage destruction, leading to midcarpal SLAC - narrowing and sclerosis of capitolunate joint; hence arthritis is more in midcarpal joints
Proximal migration of capitate into scapholunate space
Lunate - DISI deformity
Radiographs:
AP view:
Elongated appearance of radial styloid
Vertical orientation of scaphoid
scapholunate dissociation
Ulnolunate translocation
Lateral view:
Increased scapholunate angle
Dorsiflexion of lunate
DISI deformity
Surgical options:
Limited wrist fusion
Proximal row carpectomy
Total wrist orthodesis
Total wrist orthoplasty
