Bone plates for osteosynthesis - a systematic review of test methods and parameters for biomechanical testing

Bone plates for osteosynthesis are subject to biomechanical testing for safety and regulatory purposes. International standards applicable for those devices are designed for bone plates used in the surgical fixation of the skeletal system but not necessarily for all device variants available. We intend to summarize the test methods and parameters presented in the literature to evaluate bone plates in a clinical environment, especially for modern anatomically shaped implants. We conducted a systematic review on published biomechanical studies for lower and upper extremities (clavicle, humerus, ulna, radius, metacarpal, femur, tibia, fibula, metatarsal). The search process led to the identification of 159 relevant articles containing 330 individual tests, which were analyzed concerning various test criteria including test methods and parameters per bone segment for static and dynamic loading tests, as well as number of cycles, chosen bone model and outcome variables. The biomechanical literature for bone plates is diverse, inconsistent and heterogeneous. Test methods are not commonly applied per bone plate location and test parameters are not uniformly specified and displayed. They vary in particular for bending and torsion tests as well as for the number of loading cycles for dynamic testing. Outcome variables are not commonly applied nor defined. Consequently this paper is the first in a planned chronological series of three to identify the need (this publication), to develop a systematic procedural approach (2. publication) and to apply the process exemplary on a bone plate sample (3. publication).