Chronic carpal instability

Abstract

Most wrists with an unsolved bone or ligament injury evolve into permanent, dysfunctional and often painful malalignment. When progressively loaded, a malaligned carpus no longer dissipates its internal stresses across central, cartilage covered joint surfaces, but tends to shift loads towards the periphery of the joint, inducing progressive osteoarthritis. This often results in capsular retraction and further wrist dysfunction. When an unstable wrist moves, sudden changes in bone positioning may occur (wrist clunking), which can also result in painful synovitis and muscle protective contractures. Indeed, the chances of an unstable wrist developing painful osteoarthritis are high, not only as a result of abnormal transfer of loads (dyskinetics) but also because the presence of dysharmonic motion (dyskinematics) [1, 2].