Angulated versus parallel headless cannulated screw fixation for type 1 capitellum fracture: A finite element study

Aim: The unique shape and vascularization make capitellar fractures challenging to treat. In such cases, screw inclination is crucial to achieve stable fixation. In the present study, we aimed to evaluate the mechanical outcome of the different fixation angles formed by headless cannulated screws for treatment of type 1 capitellum fracture and compared interfragmentary displacement (IFD) using finite element analysis (FEA). Material and Methods: In our study, three-dimensional finite element stress analysis was applied using the isotropic materials and static linear analysis. Stochastic screw inclination scenarios (Case 1, Case 2, Case 3, and Case 4) were generated, and perpendicular application of loads were simulated with magnitudes between 50 and 300 N on the elbow at angulations from 0º to 145º. The IFD in the four different screw inclination pairs were listed in the ANSYS general end processor. Relative IFD was calculated by measuring the total displacements in the X/Y/Z planes from 16 different points.Results: According to the modeling, the magnitude of IFD was significantly different in terms of the force and the case factors under four altered forces. Analysis of displacement exhibited a significant difference in the force values of ‘100N/200N/300N’ and in the screw inclinations of Case 2 only. Although the interaction effect between the Force*Case was observed to be low, the most noticeable results were obtained from the “300N*Case 2.” pair compared to the others (p

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1. Kozin S. Capitellum Fractures. In Mirzayan, R, Itamura, J, editors. Shoulder and Elbow Trauma. 1 ed. New York: Thieme Med Publishers 2004;26-33.
2. London JT. Kinematics of the elbow. J Bone Joint Surg Am 1981;63:529-35.
3. Yamaguchi K, Sweet FA, Bindra R, et al. The extraosseous and intraosseous arterial anatomy of the adult elbow. J Bone Joint Surg Am 1997;79:1653- 62.
4. Jupiter JM. Fractures in the distal humerus in the adult. In Morrey, B, editor. The elbow and its disorders. 2 ed. Philadelphia: WB Saunders; 1993;351.
5. Ochner RS, Bloom H, Palumbo RC, et al. Closed reduction of coronal fractures of the capitellum. J Trauma 1996;40:199-203.
6. Liberman N, Katz T, Howard CB, et al. Fixation of capitellar fractures with the Herbert screw. Arch Orthop Trauma Surg 1991;110:155-7.
7. Hardy P, Menguy F, Guillot S. Arthroscopic treatment of capitellum fracture of the humerus. Arthroscopy 2002;18:422-6.
8. Christopher FB. Conservative treatment of fracture of the capitellum. JBJS 1935;17:489-92.
9. Alvarez E, Patel MR, Nimberg G, Pearlman HS. Fracture of the capitulum humeri. J Bone Joint Surg Am 1975;57:1093-6.
10. Karaman HY, Karpat C, Dhanasekaran F, et al. Structural analysis of dental implants with various micro groove profiles. IRJAES 2018;3:101-4.
11. Heiner AD. Structural properties of fourthgeneration composite femurs and tibias. J Biomech 2008;41:3282-4.
12. Grassi L, Vaananen SP, Amin Yavari S, et al. Experimental validation of finite element model for proximal composite femur using optical measurements. J Mech Behav Biomed Mater 2013;21:86-94.
13. Gardner MP, Chong AC, Pollock AG, et al. Mechanical evaluation of large-size fourth-generation composite femur and tibia models. Ann Biomed Eng 2010;38:613- 20.
14. Rancourt D, Shirazi-Adl A, Drouin G, et al. Friction properties of the interface between porous-surfaced metals and tibial cancellous bone. J Biomed Mater Res 1990;24:1503-19.
15. Parekh J, Shepherd DE, Hukins DW, et al. In vitro investigation of friction at the interface between bone and a surgical instrument. Proc Inst Mech Eng H 2013;227:712-8.
16. Dirschl DR, Marsh JL, Buckwalter JA, et al. Articular fractures. J Am Acad Orthop Surg 2004;12:416-23.
17. Marsh JL, Buckwalter J, Gelberman R, et al. Articular fractures: does an anatomic reduction really change the result? J Bone Joint Surg Am 2002;84:1259-71.
18. Chuckpaiwong B, Suwanwong P, Harnroongroj T. Roofarc angle and weight-bearing area of the acetabulum. Injury 2009;40:1064-6.
19. Bacon S, Smith WR, Morgan SJ, et al. A retrospective analysis of comminuted intra-articular fractures of the tibial plafond: Open reduction and internal fixation versus external Ilizarov fixation. Injury 2008;39:196- 202.
20. Aminian A, Howe CR, Sangeorzan BJ, et al. Ipsilateral talar and calcaneal fractures: a retrospective review of complications and sequelae. Injury 2009;40:139-45.
21. Elkowitz SJ, Polatsch DB, Egol KA, et al. Capitellum fractures: a biomechanical evaluation of three fixation methods. J Orthop Trauma 2002;16:503-6.
22. Elkowitz SJ, Kubiak EN, Polatsch D, et al. Comparison of two headless screw designs for fixation of capitellum fractures. Bull Hosp Jt Dis 2003;61:123-6.
23. Waddell JP, Hatch J, Richards R. Supracondylar fractures of the humerus--results of surgical treatment. J Trauma 1988;28:1615-21.
24. Mighell M, Virani NA, Shannon R, Echols EL, Jr., Badman BL, Keating CJ. Large coronal shear fractures of the capitellum and trochlea treated with headless compression screws. J Shoulder Elbow Surg 2010;19:38-45.
25. Dubberley JH, Faber KJ, Macdermid JC, et al. Outcome after open reduction and internal fixation of capitellar and trochlear fractures. J Bone Joint Surg Am 2006;88:46-54.
26. Ruchelsman DE, Tejwani NC, Kwon YW, Egol KA. Coronal plane partial articular fractures of the distal humerus: current concepts in management. J Am Acad Orthop Surg 2008;16:716-28.