Objective. To find out whether superior or anterior plating osteosynthesis of clavicular fractures with and without inferior cortical defect provides more stability.Design. The bearing of maximal bending moment of the osteosyntheses was determined by applying a load from a universal testing machine.Background. A plate is recommended for internal fixation of the clavicular fracture. Stability of the osteosynthesis depends on placing of the plate at anterior or superior aspect of the clavicle. Whereas, the pattern of the fracture also influences stability.Methods. Pairs of fresh cadaveric clavicles were used. The fractures were created at middle clavicle. Both superior and anterior plating fixation of both patterns of the fractures were performed. A compression load was applied at lateral end of the clavicle and maximal bending moment was calculated.Results. For fractures without inferior cortical defect, the superior plating could withstand 12.05 (sd, 1.74) Nm and 8.69 (sd, 1.56) Nm for the anterior plating. For the fractures with inferior cortical defect, the superior plating could withstand 7.87 (sd, 2.58) Nm, but 10.26 (sd, 2.19) Nm for the anterior plating.Conclusions. The superior plating of the fracture without inferior cortical defect provides more stability against the bending moment than the anterior plating (P = 0.008). Whereas, the anterior plating of the fracture with inferior cortical defect provides more stability (P = 0.025).RelevanceWhen plating a clavicular fracture without inferior cortical defect is performed, the plate should be placed at superior aspect of the clavicle for achieving more stability of the osteosynthesis against the bending moment. On the other hand, when the fracture has an inferior cortical defect, the plate should be placed at the anterior aspect of the clavicle.