Dual Plating for Fixation of Humeral Shaft Fractures: Mechanical Comparison of Various Combinations of Plate Lengths

Abstract

Background: The plate configuration was found inconclusive on the biomechanical effects of the plate size and hole number for dual plate construct in humeral shaft fractures. The purpose of this study is to test the biomechanical stability of various dual plate constructions.
Methods: 24 left sawbone humeri with a comminuted midshaft humeral fracture model was used. Four groups of  plate constructs were tested: Lateally fixed 8 hole locking plate  and screws were combined with anteriorly none; 4 hole; 6 hole, 8 hole locking plates in groups I, II, III and IV respectively. The alterations in axial, bending and torsional angles were recorded.
Results: There were no fixation failure during axial, bending or torsional stiffness testing within the elastic behavior limits. Axial stiffness in GroupVI was higher than in GroupI(P=0.004), in GroupII(P=0.025), and in GroupIII(P=0.006). The torsional stiffness in GroupI was lower than GroupII(P=0.01), GroupIII(P=0.01), and GroupIV(P=0.006). The posterior to anterior bending stiffness in GroupI was lower than GroupII(P=0.004), GroupIII(P=0.0037), and GroupIV(P=0.01); the lateral to medial bending stiffness in GroupI, was lower than Group II(P=0.004), Group III(P=0.004), and Group IV(P=0.004); the medial to lateral bending stiffness in GroupI, was lower than Group II(P=0.004), GroupIII(P=0.004), and GroupIV(P=0.004).
Discussion The close stiffness values for the 8 to 4 hole and 8 to 6 hole plate construction, 8 to 4 hole construction may be suggested as an option in young adults while 8 to 8 hole combination which is the most stiff combination among the other groups, may be an option for osteoporotic patients.

 

DOI: 10.3944/AOTT.2015.15.0275
This abstract belongs to the un-edited version of the article and is only for informative purposes. Published version may differ from the current version.

Keywords

• Humeral Shaft Fractures;Dual Plate;fixation.