A biomechanical comparison of proximal femoral nails and locking proximal anatomic femoral plates in femoral fracture fixation: A study on synthetic bones

Korhan Ozkan, İsmail Türkmen, Adem Sahin, Yavuz Yildiz, Selim Erturk, Mehmet Salih Soylemez, Korhan Ozkan, İsmail Türkmen, Adem Sahin, Yavuz Yildiz, Selim Erturk, Mehmet Salih Soylemez

Abstract

Background: The incidence of fractures in the trochanteric area has risen with the increasing numbers of elderly people with osteoporosis. Although dynamic hip screw fixation is the gold standard for the treatment of stable intertrochanteric femur fractures, treatment of unstable intertrochanteric femur fractures still remains controversial. Intramedullary devices such as Gamma nail or proximal femoral nail and proximal anatomic femur plates are in use for the treatment of intertrochanteric femur fractures. There are still many investigations to find the optimal implant to treat these fractures with minimum complications. For this reason, we aimed to perform a biomechanical comparison of the proximal femoral nail and the locking proximal anatomic femoral plate in the treatment of unstable intertrochanteric fractures.

Materials and methods: Twenty synthetic, third generation human femur models, obtained for this purpose, were divided into two groups of 10 bones each. Femurs were provided as a standard representation of AO/Orthopedic Trauma Associationtype 31-A2 unstable fractures. Two types of implantations were inserted: the proximal femoral intramedullary nail in the first group and the locking anatomic femoral plate in the second group. Axial load was applied to the fracture models through the femoral head using a material testing machine, and the biomechanical properties of the implant types were compared.

Result: Nail and plate models were locked distally at the same level. Axial steady load with a 5 mm/m velocity was applied through the mechanical axis of femur bone models. Axial loading in the proximal femoral intramedullary nail group was 1.78-fold greater compared to the plate group. All bones that had the plate applied were fractured in the portion containing the distal locking screw.

Conclusion: The proximal femoral intramedullary nail provides more stability and allows for earlier weight bearing than the locking plate when used for the treatment of unstable intertrochanteric fractures of the femur. Clinicians should be cautious for early weight bearing with locking plate for unstable intertrochanteric femur fractures.

Keywords: Biomechanical comparison; Femur; femoral neck fractures; fracture fixation; intertrochanteric femur fractures; intramedullary; intramedullary nail; proximal anatomic femoral plate.

Conflict of interest statement

Conflict of Interest: None.

Figures

Figure 1
Figure 1
X-ray images of bone-implant construct models: (a and b) anteroposterior and lateral views of the intramedullary nail applied on fractured femur model. (c and d) Anteroposterior and lateral view of the plate applied on fractured femur model
Figure 2
Figure 2
Pictures of bone-implant construct models: (a and b) Anteroposterior and lateral view of the plate applied on fractured femur model. (c and d) Anteroposterior and lateral view of the intramedullary nail applied fractured femur model
Figure 3
Figure 3
Positioning of bone-implant construct and biomechanical loading test with Shimadzu Autograph AGS testing device
Figure 4
Figure 4
Fracture patterns for two groups after loading test. (a) Fracture occurred just below the plate in plate applied bone model. (b) Fracture occurred at the tip of the nail in the intramedullary nail applied bone model. (c) Displaced butterfly fragment occurred distally in the intramedullary nail applied bone model
Figure 5
Figure 5
Force-time curves for the bone models numbered 2-5-7 with plates applied
Figure 6
Figure 6
Force-time curves for the proximal femoral nail bone models numbered 3-4-5-6

References

    1. Weller I, Wai EK, Jaglal S, Kreder HJ. The effect of hospital type and surgical delay on mortality after surgery for hip fracture. J Bone Joint Surg Br. 2005;87:361–6.
    1. Kregor PJ, Obremskey WT, Kreder HJ, Swiontkowski MF, Evidence-Based Orthopaedic Trauma Working Group. Unstable pertrochanteric femoral fractures. J Orthop Trauma. 2005;19:63–6.
    1. Min WK, Kim SY, Kim TK, Lee KB, Cho MR, Ha YC, et al. Proximal femoral nail for the treatment of reverse obliquity intertrochanteric fractures compared with gamma nail. J Trauma. 2007;63:1054–60.
    1. Parker MJ, Handoll HH. Intramedullary nails for extracapsular hip fractures in adults. Cochrane Database Syst Rev. 2006;19(3):CD004961.
    1. Rosenblum SF, Zuckerman JD, Kummer FJ, Tam BS. A biomechanical evaluation of the Gamma nail. J Bone Joint Surg Br. 1992;74:352–7.
    1. Werner-Tutschku W, Lajtai G, Schmiedhuber G, Lang T, Pirkl C, Orthner E. Intra-and perioperative complications in the stabilization of per-and subtrochanteric femoral fractures by means of PFN. Unfallchirurg. 2002;105:881–5.
    1. Streubel PN, Moustoukas MJ, Obremskey WT. Mechanical failure after locking plate fixation of unstable intertrochanteric femur fractures. J Orthop Trauma. 2013;27:22–8.
    1. Crist BD, Khalafi A, Hazelwood SJ, Lee MA. A biomechanical comparison of locked plate fixation with percutaneous insertion capability versus the angled blade plate in a subtrochanteric fracture gap model. J Orthop Trauma. 2009;23:622–7.
    1. Floyd JC, O’ Toole RV, Stall A, Forward DP, Nabili M, Shillingburg D, et al. Biomechanical comparison of proximal locking plates and blade plates for the treatment of comminuted subtrochanteric femoral fractures. J Orthop Trauma. 2009;23:628–33.
    1. Kim JW, Oh CW, Byun YS, Oh JK, Kim HJ, Min WK, et al. A biomechanical analysis of locking plate fixation with minimally invasive plate osteosynthesis in a subtrochanteric fracture model. J Trauma. 2011;70:E19–23.
    1. Levy RN, Capozzi JD, Mont MA. Intertrochanteric hip fractures. In: Browner DB, Jupiter JB, Levine AM, editors. Skeletal Trauma. Vol. 2. USA: WB Saunders Company; 1992. pp. 1443–71.
    1. Boldin C, Seibert FJ, Fankhauser F, Peicha G, Grechenig W, Szyszkowitz R. The proximal femoral nail (PFN) – A minimal invasive treatment of unstable proximal femoral fractures: A prospective study of 55 patients with a followup of 15 months. Acta Orthop Scand. 2003;74:53–8.
    1. Hasenboehler EA, Agudelo JF, Morgan SJ, Smith WR, Hak DJ, Stahel PF. Treatment of complex proximal femoral fractures with the proximal femur locking compression plate. Orthopedics. 2007;30:618–23.
    1. Forward DP, Doro CJ, O’ Toole RV, Kim H, Floyd JC, Sciadini MF, et al. A biomechanical comparison of a locking plate, a nail, and a 95° angled blade plate for fixation of subtrochanteric femoral fractures. J Orthop Trauma. 2012;26:334–40.
    1. Ballal MS, Emms N, Thomas G. Proximal femoral nail failures in extracapsular fractures of the hip. J Orthop Surg (Hong Kong) 2008;16:146–9.
    1. Akan K, Cift H, Ozkan K, Eceviz E, Tasyikan L, Eren A. Effect of osteoporosis on clinical outcomes in intertrochanteric hip fractures treated with a proximal femoral nail. J Int Med Res. 2011;39:857–65.
    1. Malkani AL, Karandikar N. Revision fixation for failed intertrochanteric fractures. Tech Orthop. 2002;17:443–7.
    1. Parker MJ, Handoll HH. Gamma and other cephalocondylic intramedullary nails versus extramedullary implants for extracapsular hip fractures in adults. Cochrane Database Syst Rev. 2008;16(3):CD000093.
    1. Jacobs RR, McClain O, Armstrong HJ. Internal fixation of intertrochanteric hip fractures: A clinical and biomechanical study. Clin Orthop Relat Res. 1980;146:62–70.

Source: PubMed

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