A case study of a failed humeral shaft locking compression plate is presented, starting with a clinical case where failure occurred and an implant replacement was required. This study uses finite element method (FEM) in order to determine the failure modes for the clinical case. Four loading scenarios that simulate daily life activities were considered for determining the stress distribution in a humeral shaft locking compression plate (LCP). Referring to the simulation results, the failure analysis was performed on the explant. Using fracture surface investigation methods, stereomicroscopy and scanning electron microscopy (SEM), a mixed mode failure was determined. An initial fatigue failure occurred followed by a sudden failure of the plate implant as a consequence of patient’s fall. The fracture morphology was mostly masked by galling; the fractured components were in a sliding contact. Using information from simulations, the loading was inferred and correlated with fracture site and surface features.

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The paper presents the structural and dimensional differences of rectangular shape samples manufactured by selective laser sintering (SLS) according to three process sinterization energies. In this study we determine the geometrical and structural characteristics of biocompatible PA2200 polyamide manufactured at a low energy density E1, and intermediate value E2 and a high energy density E3. Relaying on these results, four custom-made medical parts have been built using biocompatible polyamide PA2200 powder, in order to evaluate their performances.

The general purpose of this study was to assess the accuracy of geometric characteristics of electronic footprints acquired with Zebris FDM force platform based on comparison with corresponding characteristics of conventional ink footprints. The paper presents a comparative analysis of contact areas and plantar arch index calculated from simultaneously acquired ink and electronic footprints. The areas of the three main regions of the footprints have been determined using common image processing software. The plantar arch index was calculated based on Cavanagh method. The comparative analysis evidences the differences between the geometric characteristics. The total contact area is slightly overestimated in case of the electronic footprints. The electronic footprints overestimate fore-foot and rear-foot areas and underestimate mid-foot area. The mean values of AI in case of ink footprints generally have greater values than in case of electronic footprints.