Medial açıklığı olan proksimal humerus kırıklarında kilitli plak tespiti üzerinde medial kortikal ve medial vida desteklerinin biyomekanik etkisi:Sonlu elemanlar yöntemi

Öz

Amaç: Bu sonlu elemanlar yöntemi, medial açıklığı olan proksimal humerus kırıklarının implant-kemik ara yüzeyindeki yüklerde medial kortikal ve medial vida desteklerinin etkisini araştırmayı amaçladı.

Çalışma planı: Sağlıklı bir gönüllüden alınan sağlam humerus 3 boyutlu (3D) bilgisayar-destekli tasarım (BDT) modelinde kaynak olarak kullanıldı. Kilitli plak sisteminin 3D BDT modeli, üretici firmanın kılavuzundaki bilgiler üzerine kuruldu. Humerusun proksimal kısmı, standart üç-parça kırıkları yaratmak için osteotomize edildi ve sonra –MKD grubu (medial kortikal desteği eksik ve bu eksiklik kırıklarda 5 mm’lik medial kemik açıklığı kaynaklı) ve +MKD grubu (medial kortikal destek mevcut ve bu destek kırıklarda kortikalden kortikale medial temas kaynaklı) olarak ikiye ayrıldı. Her iki kırık grubu ya +MVD (ki burada medial vida desteği kilitli plak sistemine ilave iki kalkar vidası eklentisi ile sağlandı) ya da –MVD (ki burada medial vida desteği eksikliği kilitli plak sistemine ilave iki kalkar vidası eklenmemesi ile sağlandı) ile sırasıyla onarıldı. Bütün modelleme 90°’lik kol abdüksiyonunu yansıtmak için yürütüldü.

Bulgular: Vida-kemik ara yüzeyinde medial vida desteği ve medial kortikal destek maksimum kayma gerilimini sırasıyla %17 ve %23 oranında azalttı. Kilitli plak üzerinde, medial vida desteği ve medial kortikal destek maksimum von Mises gerilimini sırasıyla %11 ve %22 oranında azalttı. Ancak, bu ikisinin kombinasyonunun vida-kemik ara yüzeyi için maksimum kayma gerilimini %56 oranında ve kilitli plak için maksimum von Mises gerilimini %54 oranında azalttığı göründü.

Çıkarımlar: Medial açıklığı olan proksimal humerus kırıklarının kilitli plak tespiti sırasında varusta iyi medial kortikal temas ile bileşik kalkar vida yerleştirilmesi tespit için optimal stabilite sağlayabilir.

 

Anahtar Kelimeler

• Biyomekanik; sonlu elemanlar yöntemi; kilitli plak; omuz kırıkları.

Biomechanical effect of medial cortical support and medial screw support on locking plate fixation in proximal humeral fractures with a medial gap: a finite element analysis

Öz

Objective: This finite element analysis aimed to examine the effect of medial cortical support and medial screw support on loads at the implant-bone interface of locking plate fixation of proximal humeral fractures with a medial gap.

Methods: An intact humerus from a healthy volunteer was used as the basis for a 3-dimensional (3D) computer-aided design (CAD) model. The 3D CAD model of the locking plate system was based on information in the manufacturer’s catalogue. The proximal part of the humerus was osteotomized to create standard three-part fractures, which were then divided into a –MSC group (which lacked medial cortical support, and in which fractures with a 5-mm medial bone gap simulated this lack) and +MCS group (which had medial cortical support, and in which fractures with medial corticalto-cortical contact simulated this). Both fracture groups were respectively fixed with either +MSS (in which medial screw support was simulated by the addition of two calcar screws to the locking plate system), or with –MSS (in which the lack of medial screw support was simulated by absence of the two additional calcar screws to the locking plate system). All the modeling was conducted to represent 90° arm abduction.

Results: On the screw-bone interface, medial screw support and medial cortical support decreased maximum shear stress by 17% and 23% respectively. On the locking plate, medial screw support and medial cortical support decreased maximum von Mises stress by 11% and 22% respectively. However,a combination of these two appeared to decrease maximum shear stress by 56% for the screw-bone interface, and maximum von Mises stress by 54% for the locking plate.

Conclusion: Placement of calcar screws combined with good medial cortical contact in varus in locking plate fixation of proximal humeral fractures with a medial gap may provide optimal stability for the fixation.

 

Anahtar Kelimeler

• Biomechanics
• finite element analysis
• locking plate
• shoulder fractures

Kaynakça

1. Baron JA, Karagas M, Barrett J, Kniffin W, Malenka D, Mayor M, et al. Basic epidemiology of fractures of the up- per and lower limb among Americans over 65 years of age. Epidemiology 1996;7:612–8.
2. Roux A, Decroocq L, El Batti S, Bonnevialle N, Moineau G, Trojani C, et al. Epidemiology of proximal humerus fractures managed in a trauma center. Orthop Traumatol Surg Res 2012;98:715–9.
3. Calvo E, Morcillo D, Foruria AM, Redondo-Santamaría E, Osorio-Picorne F, Caeiro JR; GEIOS-SECOT Outpa- tient Osteoporotic Fracture Study Group. Nondisplaced proximal humeral fractures: high incidence among outpa- tient-treated osteoporotic fractures and severe impact on upper extremity function and patient subjective health per- ception. J Shoulder Elbow Surg 2011;20:795–801.
4. Iannotti JP, Ramsey ML, Williams GR Jr, Warner JJ. Non- prosthetic management of proximal humeral fractures. In- str Course Lect 2004;53:403–16.
5. Volgas DA, Stannard JP, Alonso JE. Nonunions of the hu- merus. Clin Orthop Relat Res 2004;419:46–50.
6. Röderer G, Gebhard F, Krischak G, Wilke HJ, Claes L. Bio- mechanical in vitro assessment of fixed angle plating using a new concept of locking for the treatment of osteoporotic proximal humerus fractures. Int Orthop 2011;35:535–41.
7. Seide K, Triebe J, Faschingbauer M, Schulz AP, Püschel K, Mehrtens G, et al. Locked vs. unlocked plate osteosynthe- sis of the proximal humerus - a biomechanical study. Clin Biomech (Bristol, Avon) 2007;22:176–82.
8. Siffri PC, Peindl RD, Coley ER, Norton J, Connor PM, Kellam JF. Biomechanical analysis of blade plate versus locking plate fixation for a proximal humerus fracture: comparison using cadaveric and synthetic humeri. J Or- thop Trauma 2006;20:547–54.

9. Foruria AM, Carrascal MT, Revilla C, Munuera L, San- chez-Sotelo J. Proximal humerus fracture rotational sta- bility after fixation using a locking plate or a fixed-angle locked nail: the role of implant stiffness. Clin Biomech (Bristol, Avon) 2010;25:307–11.
10. Barlow JD, Sanchez-Sotelo J, Torchia M. Proximal hu- merus fractures in the elderly can be reliably fixed with a “hybrid” locked-plating technique. Clin Orthop Relat Res 2011;469:3281–91.
11. Leonard M, Mokotedi L, Alao U, Glynn A, Dolan M, Fleming P. The use of locking plates in proximal humeral fractures: Comparison of outcome by patient age and frac- ture pattern. Int J Shoulder Surg 2009;3:85–9.
12. Olerud P, Ahrengart L, Söderqvist A, Saving J, Tidermark J. Quality of life and functional outcome after a 2-part proximal humeral fracture: a prospective cohort study on 50 patients treated with a locking plate. J Shoulder Elbow Surg 2010;19:814–22.
13. Acklin YP, Stoffel K, Sommer C. A prospective analysis of the functional and radiological outcomes of minimally invasive plating in proximal humerus fractures. Injury 2013;44:456–60.
14. Osterhoff G, Hoch A, Wanner GA, Simmen HP, Werner CM. Calcar comminution as prognostic factor of clinical outcome after locking plate fixation of proximal humeral fractures. Injury 2012;43:1651–6.
15. Solberg BD, Moon CN, Franco DP, Paiement GD. Surgi- cal treatment of three and four-part proximal humeral frac- tures. J Bone Joint Surg Am 2009;91:1689–97.
16. Jost B, Spross C, Grehn H, Gerber C. Locking plate fixa- tion of fractures of the proximal humerus: analysis of com- plications, revision strategies and outcome. J Shoulder El- bow Surg 2013;22:542–9.
17. Badman B, Frankle M, Keating C, Henderson L, Brooks J, Mighell M. Results of proximal humeral locked plating with supplemental suture fixation of rotator cuff. J Shoul- der Elbow Surg 2011;20:616–24.
18. Pak P, Eng K, Page RS. Fixed-angle locking proximal hu- merus plate: an evaluation of functional results and im- plant-related outcomes. ANZ J Surg 2013;83:878–82.
19. Thanasas C, Kontakis G, Angoules A, Limb D, Gian- noudis P. Treatment of proximal humerus fractures with locking plates: a systematic review. J Shoulder Elbow Surg 2009;18:837–44.
20. Königshausen M, Kübler L, Godry H, Citak M, Schild- hauer TA, Seybold D. Clinical outcome and complications using a polyaxial locking plate in the treatment of displaced proximal humerus fractures. A reliable system? Injury 2012;43:223–31.
21. Jung SW. Indirect reduction maneuver and minimally in- vasive approach for displaced proximal humerus fractures in elderly patients. Clin Orthop Surg 2013;5:66–73.
22. Cofield RH. Comminuted fractures of the proximal hu- merus. Clin Orthop Relat Res 1988;230:49–57.
23. Lescheid J, Zdero R, Shah S, Kuzyk PR, Schemitsch EH. The biomechanics of locked plating for repairing proximal humerus fractures with or without medial cortical support. J Trauma 2010;69:1235–42.
24. Osterhoff G, Ossendorf C, Wanner GA, Simmen HP, Werner CM. The calcar screw in angular stable plate fixa- tion of proximal humeral fractures-a case study. J Orthop Surg Res 2011;6:50.
25. Gardner MJ, Weil Y, Barker JU, Kelly BT, Helfet DL, Lorich DG. The importance of medial support in locked plating of proximal humerus fractures. J Orthop Trauma 2007;21:185–91.
26. Rho JY, Ashman RB, Turner CH. Young’s modulus of tra- becular and cortical bone material: ultrasonic and micro- tensile measurements. J Biomech 1993;26:111–9.
27. Feerick EM, Kennedy J, Mullett H, FitzPatrick D, Mc- Garry P. Investigation of metallic and carbon fibre PEEK fracture fixation devices for three-part proximal humeral fractures. Med Eng Phys 2013;35:712–22.
28. Poppen NK, Walker PS. Forces at the glenohumeral joint in abduction. Clin Orthop Relat Res 1978;135:165–70.
29. Maier D, Jäger M, Strohm PC, Südkamp NP. Treatment of proximal humeral fractures - a review of current con- cepts enlightened by basic principles. Acta Chir Orthop Traumatol Cech 2012;79:307–16.
30. Clavert P, Adam P, Bevort A, Bonnomet F, Kempf JF. Pit- falls and complications with locking plate for proximal hu- merus fracture. J Shoulder Elbow Surg 2010;19:489–94.
31. Greiner S, Kääb MJ, Haas NP, Bail HJ. Humeral head necrosis rate at mid-term follow-up after open reduction and angular stable plate fixation for proximal humeral frac- tures. Injury 2009;40:186–91.
32. Lill H, Hepp P, Korner J, Kassi JP, Verheyden AP, Josten C, et al. Proximal humeral fractures: how stiff should an implant be? A comparative mechanical study with new implants in human specimens. Arch Orthop Trauma Surg 2003;123:74–81.
33. Liew AS, Johnson JA, Patterson SD, King GJ, Chess DG. Effect of screw placement on fixation in the humeral head. J Shoulder Elbow Surg. 2000;9:423–6.
34. Schulte LM, Matteini LE, Neviaser RJ. Proximal periartic- ular locking plates in proximal humeral fractures: function- al outcomes. J Shoulder Elbow Surg 2011;20:1234–40.
35. Zhang L, Zheng J, Wang W, Lin G, Huang Y, Zheng J, et al. The clinical benefit of medial support screws in locking plating of proximal humerus fractures: a prospective ran- domized study. Int Orthop 2011;35:1655–61.
36. Clavert P, Zerah M, Krier J, Mille P, Kempf JF, Kahn JL. Finite element analysis of the strain distribution in the humeral head tubercles during abduction: compari- son of young and osteoporotic bone. Surg Radiol Anat 2006;28:581–7.