The Pathoanatomy and Biomechanics of Kienböck Disease.

Kienböck disease (KD) involves osseous, vascular, and chondral aspects of the lunate and wrist. We present our theories on the etiology and pathogenesis of the condition based on basic science models, seminal literature, personal case experience, and kinematic observations of the Kienböck wrist. Three phenotypes of Kienböck disease occur, and each tends to have different morphology, rates of progression, and disease pattern. The lunate fracture in KD is well-recognized but different fracture types can occur. Dynamic assessment of the Kienböck wrist allows assessment of the complex kinematics of KD. Disease onset and progression require a "perfect storm" of risk factors.