RESUMO
Hypercompetitiveness reflects the need to compete and win at all costs as a means of maintaining or enhancing one's own self-worth (Horney, 1937; Ryckman, Hammer, Kaczor, & Gold, 1990). This need to win at any cost is linked to expressions of verbal and physical aggression, which may take a toll on important relationships (Hibbard & Buhrmester, 2010). We sought to explore whether parental bonds with mothers and fathers (i.e., care, rejection, autonomy, and overprotection) were indirectly linked to aggression via the mediating mechanisms of hypercompetitiveness and feelings of anger. A sample of 581 university students (316 females; 265 males) were used to examine a multiple-group structural equation model. Tests of structural invariance revealed clear moderation by gender. For instance, the pathway from verbal to physical aggression was stronger for males compared to females. For females only, higher levels of father care were indirectly linked to fewer acts of physical aggression. For both genders, higher levels of mother overprotection were indirectly linked to more acts of physical aggression through increased hypercompetitiveness and, in turn, more feelings of anger. Findings regarding maternal overprotection are consistent with both Evolutionary and Social Learning theories of behavior.
RESUMO
BACKGROUND: Limited biomechanical data exist for dual small plate fixation of midshaft clavicle fractures, and no prior study has concurrently compared dual small plating to larger superior or anteroinferior single plate and screw constructs. PURPOSE: To biomechanically compare dual small orthogonal plating, superior plating, and anteroinferior plating of midshaft clavicle fractures by use of a cadaveric model. STUDY DESIGN: Descriptive laboratory study. METHODS: The study used 18 cadaveric clavicle specimens (9 pairs total), and 3 plating techniques were studied: anteroinferior, superior, and dual. The dual plating technique used smaller diameter plates and screws (1.6-mm thickness) than the other, single plate techniques (3.3-mm thickness). Each of the 9 clavicle pairs was randomly assigned a combination of 2 plating techniques, and randomization was used to determine which techniques were used for the right and left specimens. Clavicles were plated and then osteotomized to create an inferior butterfly fracture model, which was then fixed with a single interfragmentary screw. Clavicle specimens were then potted for mechanical testing. Initial bending, axial, and torsional stiffness of each construct was determined through use of a randomized nondestructive cyclic testing protocol followed by load to failure. RESULTS: No significant differences were found in cyclical axial (P = .667) or torsional (P = .526) stiffness between plating groups. Anteroinferior plating demonstrated significantly higher cyclical bending stiffness than superior plating (P = .005). No significant difference was found in bending stiffness between dual plating and either anteroinferior (P = .129) or superior plating (P = .067). No significant difference was noted in load to failure among plating methods (P = .353). CONCLUSION: Dual plating with a smaller plate-screw construct is biomechanically similar to superior and anteroinferior single plate fixation that uses larger plate-screw constructs. No significant differences were found between dual plating and either superior or anteroinferior single plating in axial, bending, or torsional stiffness or in bending load to failure. Dual small plating is a viable option for fixing midshaft clavicle fractures and may be a useful low-profile technique that avoids a larger and more prominent plate-screw construct. CLINICAL RELEVANCE: Plate prominence and hardware irritation are commonly reported complaints and reasons for revision surgery after plate fixation of midshaft clavicle fractures. Dual small plate fixation has been used to improve cosmetic acceptability, minimize hardware irritation, and decrease reoperation rate. Biomechanically, dual small plate fixation performed similarly to larger single plate fixation in this cadaveric model of butterfly fracture.
