Generating a musculoskeletal model of the index finger from MR, CT and optical motion capture data

Postoperative success in replacing the proximal interphalangeal (PIP) joint is markedly inferior to large lower limb joints. The mean revision rate of primary total knee replacement (TKR) is 0.48% at one year and 5.19% at twelve years [1], and in a meta-analysis Adams et al [2] found at least one complication within one year in 28% of PIP replacements (PIPR). Prior PIPR implant design studies have used measurements of cadaver models [3]. TKR research has employed robust musculoskeletal models for preclinical analysis and surgical technique development, and recent work has aimed to produce similar models of the upper limb. Past finger models represented the PIP using a simple degree of freedom (DOF) hinge [4]. It is established that the knee has complex kinematics including both rotation and translation, and aware of these relative motions, Buczek et al [5] developed a 6-DOF kinematic hand model. Eschweiler et al [6] reported a detailed musculoskeletal model of the wrist, but we are not aware of any such complex hardand soft-tissue models of the finger. We present a model of the index finger containing the distal upper extremity, with full musculoligamentous structures and anatomic joint surface geometry, in an effort to address these issues.