Black holes in hand anatomy: exploring research areas in hand surgery.

The term 'black holes' has been applied to anatomical areas needing further study. The historical account On Growth and Form (D'AW Thompson, Cambridge University Press, 1917) applies mathematical principles to explain how physical forces influence the morphology of bone, tendon, ligament and fascia. The trabecular structure of bone is maintained by force loading, providing a map of strain concentrations to better understand fracture fixation and bone healing. The flexor tendon is classified in zones of sheath pathology, but the site of tendon injury depends on the posture at the moment of injury. Ligaments are multistranded structures and in maintaining joint stability throughout motion different fibrous strands must share load by ligament buckling. The fascial description of Guimberteau visualizes the human body as consisting of microvacuoles, quantifiable from the physical Laws of Plateau. Human morphology can be understood through mathematics. These 'black holes' offer possible research avenues to manage some of the unsolved problems in hand surgery or to optimize outcomes.