This aim of this study was to assess the feasibility of designing and introducing generic 3D-printed instrumentation for routine use in total knee arthroplasty. Instruments were designed to take advantage of 3D-printing technology, particularly ensuring that all parts were pre-assembled, to theoretically reduce the time and skill required during surgery. Concerning functionality, ranges of resection angle and distance were restricted within a safe zone, while accommodating either mechanical or anatomical alignment goals. To identify the most suitable biocompatible materials, typical instrument shapes and mating parts, such as dovetails and screws, were designed and produced.Aims
Materials and Methods
Four matched pairs of fresh frozen human femora were used to compare the biomechanical properties in axial and torsional loading of a Locking Condylar Plate and a retrograde intramedullary nail. One-centimeter gap osteotomy was created in the supracondylar region to simulate an AO/OTA 33-A3 fracture. The instrumented specimens were then mechanically tested under physiologic conditions in axial and torsional loading to determine the stability of the constructs. This laboratory study enhances the biomechanical advantages of the Locking Condylar Plate when fixation stiffness is essential. Devices with head locking screws provide angular rigidity and maximize fixation stability in osteopenic bone. To compare the biomechanical properties in axial and torsional loading of a Locking Condylar Plate and a retrograde intramedullary nail. To determine the modes of failure of these two devices under axial loading. Four matched pairs of fresh frozen human femora were used. Plain film radiographs and Dexa scanning were performed to evaluate bone quality and to screen for pathologic lesions. For each pair, one femur was stabilized with the Locking Condylar Plate and the other with a retrograde nail. One-centimeter gap osteotomy was created in the supracondylar region to simulate an AO/OTA 33-A3 fracture. Radiographs were obtained to exclude iatro-genic fractures before
