Mechanical Properties of the Fingertip Pulp Under Repeated, Dynamic, Compressive Loading

High forces at the fingertips are postulated to contribute to wrist tendon and nerve disorders during repetitive hand activities such as typing (Silverstein, 1987). However, the mechanisms by which these forces may lead to the development of cumulative trauma disorders remain unknown. The fingertip pulp, the soft tissue around the palmar surface of the distal phalanx, is the interface between the external environment and the musculoskeletal system. The pulp plays an important role in the transmission of forces when the fingers contact objects. Understanding how the pulp modifies the force history is essential to the development of a biomechanical model of the hand. A tapping experiment was conducted to characterize the displacement, stiffness and energy dissipation of the in vivo fingertip pulp under repeated, dynamic, compressive loading.