Paper #I-2

A BIOMECHANICAL STUDY: EFFECTIVENESS OF A TRABECULAR METAL AUGMENTED CONSTRUCT IN LATERAL TIBIAL PLATEAU DEPRESSED FRACTURES (AO TYPE B2.2)

Benoit Benoit, MD

Montreal, QC

Co-authors

Yves Laflamme MD FRSC

Fouad Zhim MScA

Purpose

The purpose of this study is to develop a more solid surgical fixation for the AO B2.2 or Shatzker III fracture and to test a trabecular metal implant in the trauma setting for the first time.

Method

Six matched pairs of fresh frozen human cadaveric tibias were fractured and randomly assigned to be treated with either the standard of care (two 4,5mm cortical raft screws augmented with morcellized bone graft) or the new method (the same screws supporting a 2 cm diameter trabecular metal disc placed under the comminuted articular surface). The specimens were tested in cyclic loading and put at load to failure.

Results

The trabecular metal construct showed 40% less caudad displacement of the articular surface (1,43 mm vs 0,81 mm) in cyclic loading (p<0.05). Its mechanical failure occurred at a mean of 3275 N compared to 2650 N for the standard of care construct (p<0,05).

Conclusion/significance

The current study shows the biomechanical superiority of our trabecular metal construct compared to the current standard of treatment with regards to both its resistance to caudad displacement of the articular surface in cyclic loading and its strength at load to failure.