Ata C. ATALAR, Onur TUNALI, Ali ERŞEN, MEHMET İSMAİL SAFA KAPICIOĞLU, YAVUZ SAĞLAM, Mehmet S. DEMİRHAN

Biomechanical comparison of orthogonal versus parallel double plating systems in intraarticular distal humerus fractures

Objectives: In intraarticular distal humerus fractures, internalŞxation with double plates is the goldstandard treatment. However the optimal plate conŞguration is not clear in the literature. The aim of thisstudy was to compare the biomechanical stability of the parallel and the orthogonal anatomical lockingplating systems in intraarticular distal humerus fractures in artiŞcial humerus models.Methods: Intraarticular distal humerus fracture (AO13-C2) with 5 mm metaphyseal defect was created insixteen artiŞcial humeral models. Models were Şxed with either orthogonal or parallel plating systemswith locking screws (Acumed elbow plating systems). Both systems were tested for their stiffness withloads in axial compression, varus, valgus, anterior and posterior bending. Then plastic deformation aftercyclic loading in posterior bending and load to failure in posterior bending were tested. The failuremechanisms of all the samples were observed.Results: Stiffness values in every direction were not signiŞcantly different among the orthogonal and theparallel plating groups. There was no statistical difference between the two groups in plastic deformationvalues (0.31 mme0.29 mm) and load to failure tests in posterior bending (372.4 Ne379.7 N). In theorthogonal plating system most of the failures occurred due to the proximal shaft fracture, whereas inthe parallel plating system failure occurred due to the shift of the most distal screw in proximal fragment.Conclusion: Our study showed that both plating systems had similar biomechanical stabilities whenanatomic plates with distal locking screws were used in intraarticular distal humerus fractures in artiŞcial humerus models.© 2016 Turkish Association of Orthopaedics and Traumatology. Publishing services by Elsevier B.V. This isan open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)

___

Rose SH, Melton 3rd LJ, Morrey BF, Ilstrup DM, Riggs BL. Epidemiologic features of humeral fractures. Clin Orthop Relat Res. 1982;168:24e30.

Helfet DL, Hotchkiss RN. InternalŞxation of the distal humerus: a biome- chanical comparison of methods. J Orthop Trauma. 1990;4(3):260e264.

Jupiter JB, Neff U, Holzach P, Allgower M. Intercondylar fractures of the hu- merus. An operative approach. J Bone Jt Surg Am. 1985;67(2):226e239.

O'Driscoll SW. Optimizing stability in distal humeral fractureŞxation. J shoulder Elb Surg/Am Shoulder Elb Surg. 2005;14(1 suppl S), 186Se94S.

Tejwani NC, Murthy A, Park J, McLaurin TM, Egol KA, Kummer FJ. Fixation of extra-articular distal humerus fractures using one locking plate versus two reconstruction plates: a laboratory study. J trauma. 2009;66(3):795e799.

Sanchez-Sotelo J, Torchia ME, O'Driscoll SW. Principle-based internalŞxation of distal humerus fractures. Tech Hand Up Extrem Surg. 2001;5(4):179e187.

Jacobson SR, Glisson RR, Urbaniak JR. Comparison of distal humerus fracture Şxation: a biomechanical study. J South Orthop Assoc. 1997;6(4):241e249.

Self J, Viegas SF, Buford Jr WL, Patterson RM. A comparison of double-plate Şxation methods for complex distal humerus fractures. J Shoulder Elb Surg. ;4(1 Pt 1):10e16. Schemitsch EH, Tencer AF, Henley MB. Biomechanical evaluation of methods of internalŞxation of the distal humerus. J Orthop Trauma. 1994;8(6):468e475.

Korner J, Diederichs G, Arzdorf M, et al. A biomechanical evaluation of methods of distal humerus fractureŞxation using locking compression plates versus conventional reconstruction plates. J Orthop Trauma. 2004;18(5):286e293.

Stoffel K, Cunneen S, Morgan R, Nicholls R, Stachowiak G. Comparative stability of perpendicular versus parallel double-locking plating systems in osteoporotic comminuted distal humerus fractures. J Orthop Res. 2008;26(6):778e784.

Penzkofer R, Hungerer S, Wipf F, von Oldenburg G, Augat P. Anatomical plate conŞguration affects mechanical performance in distal humerus fractures. Clin Biomech (Bristol, Avon). 2010;25(10):972e978.

Kollias CM, Darcy SP, Reed JG, Rosvold JM, Shrive NG, Hildebrand KA. Distal humerus internalŞxation: a biomechanical comparison of 90 degrees and parallel constructs. Am J Orthop (Belle Mead NJ). 2010;39(9):440e444.

Zalavras CG, Vercillo MT, Jun BJ, Otarodifard K, Itamura JM, Lee TQ. Biome- chanical evaluation of parallel versus orthogonal plateŞxation of intra- articular distal humerus fractures. J Shoulder Elbow Surg. 2011;20(1):12e20.

Arnander MW, Reeves A, MacLeod IA, Pinto TM, Khaleel A. A biomechanical comparison of plate conŞguration in distal humerus fractures. J Orthop Trauma. ;22(5):332e336.

Shin SJ, Sohn HS, Do NH. A clinical comparison of two different double plating methods for intraarticular distal humerus fractures. J Shoulder Elb Surg. ;19(1):2e9.

Windolf M, Maza ER, Gueorguiev B, Braunstein V, Schwieger K. Treatment of distal humeral fractures using conventional implants. Biomechanical evalua- tion of a new implant conŞguration. BMC Musculoskelet Disord. 2010;11:172.

Schwartz A, Oka R, Odell T, Mahar A. Biomechanical comparison of two different periarticular plating systems for stabilization of complex distal hu- merus fractures. Clin Biomech (Bristol, Avon). 2006;21(9):950e955.

Schuster I, Korner J, Arzdorf M, Schwieger K, Diederichs G, Linke B. Mechanical comparison in cadaver specimens of three different 90-degree double-plate osteosyntheses for simulated C2-type distal humerus fractures with varying bone densities. J Orthop Trauma. 2008;22(2):113e120.

Marsh JL, Slongo TF, Agel J, et al. Fracture and dislocation classiŞcation com- pendium - 2007: orthopaedic Trauma Association classiŞcation, database and outcomes committee. J Orthop trauma. 2007;21(10 Suppl):S1eS133.

Koonce RC, Baldini TH, Morgan SJ. Are conventional reconstruction plates equivalent to precontoured locking plates for distal humerus fractureŞxation? A biomechanics cadaver study. Clin Biomech (Bristol, Avon). 2012;27(7): e701.

Sanchez-Sotelo J, Torchia ME, O'Driscoll SW. Complex distal humeral fractures: internalŞxation with a principle-based parallel-plate technique. J Bone Jt Surg Am. 2007;89(5):961e969.

Lee SK, Kim KJ, Park KH, Choy WS. A comparison between orthogonal and parallel plating methods for distal humerus fractures: a prospective random- ized trial. Eur J Orthop Surg traumatology Orthop traumatologie. 2014;24(7): e1131.

Alcid JG, Ahmad CS, Lee TQ. Elbow anatomy and structural biomechanics. Clin Sports Med. 2004;23(4):503e517. vii.