The role of the medial plate for Pauwels type III femoral neck fracture: a comparative mechanical study using two fixations with cannulated screws

Abstract

Background: The biomechanical behavior of Pauwels type III fractures should be taken into consideration when performing internal fixation, since this repair should resist the shear force inherent in the vertical fracture line to the greatest extent possible. Recently, the use of a small fragment plate on the medial face of the femoral neck has been proposed by some authors, with satisfactory initial results. In the current study we analyze the mechanical role a medial plate used as a buttress plate for Pauwels type III femoral neck fractures, comparing the resistance of two fixation configurations using three cannulated screws. Methods: Pauwels type III fractures were simulated in synthetic bones models and two groups were created, one of those using two parallel screws at the bottom of the femoral neck and the third screw crossing the fracture horizontally (G1), and the other fixed in the same arrangement as G1, but with the addition of a medial side plate at the apex of the fracture (G2). The constructs were subjected to axial loading until catastrophic failure. Results: The addition of a medial plate buttressing the femoral neck increased significantly the resistance to maximum loading (p = 0.003). Conclusion: Use of a medial buttress plate results in a mechanically superior construction for Pauwels type III fractures fixed with multiple cannulated screws. Lebel of evidence: Level IV. Biomechanical comparative study.

Modified F configuration in the treatment of Pauwels type III femoral neck fracture: a finite element analysis

“…In order to overcome the greater shearing force of Pauwels type III FNFs, some authors have proposed a treatment plan that uses screws and medial femoral neck plates. Related mechanical studies have shown [ 15 , 29 ] that the medial femoral neck plate can effectively resist shear forces. However, it is difficult to install a steel plate on the inner of the femoral neck because the femoral neck is deep and the area is close to the joint capsule of the hip joint.…”

Modified F Configuration in the Treatment of Pauwels Type III Femoral Neck Fracture: a Finite Element Analysis

“…In order to overcome the greater shearing force of Pauwels type III FNFs, some authors have proposed a treatment plan that uses screws and medial femoral neck plates. Related mechanical studies have shown [23,24] that the medial femoral neck plate can effectively resist shear forces. However, it is di cult to install a steel plate on the inner of the femoral neck because the femoral neck is deep and the area is close to the joint capsule of the hip joint.…”

The Role of The Medial Buttress Plate In The Treatment of Pauwels Type Ⅱ And Ⅲ Femoral Neck Fracture: A Retrospective Study And Preliminary Results

“…Kunapuli et al 16 found that the medial femoral neck buttress plate enhanced the stability of cannulated screw and sliding hip screw constructs, signi cantly increased stiffness and load to failure. Giorfano et al 17 conducted a mechanical study to analyze the role of the medial buttress plate in Pauwels type III femoral neck fractures by comparing the resistance of two xation methods using three cannulated screws, and the results showed that the medial buttress plate combined with multiple cannulated screw xation provided a mechanically superior structure for Pauwels type III fractures. Additionally, Nwankwo et al 15 conducted a mechanical test with ten matched pairs of young cadaveric femurs and concluded that the application of medial plates to Pauwels Type III femoral neck fractures signi cantly decreased angular displacement and shear.…”