Caleb Grote*, Daniel Reinhardt, Kisan Parik, Terrance McIff, Jacob Brubacher
Background: Surgical fixation of distal radius fractures with Dorsal Bridge Plating (DBP) has been proposed to allow early weight bearing/mobilization of polytrauma patients. However, there is a lack of biomechanical studies supporting the use of DBP with crutches. We hypothesized that a 3.3 mm DBP is comparable to a Volar Locking Plate (VLP) for distal radius fractures and able to allow for immediate weight bearing.
Methods: VLPs and DBPs were applied to cadaver forearms with a dorsal wedge osteotomy in an axially loaded crutch bearing model. Displacement was measured as specimens were incrementally loaded. Failure was defined as 2 mm of fracture gap displacement. T-tests were used to compare the force at failure for each group and to the target thresholds of 200 N and 400 N. Linear regression analysis was used to determine the association between bone mineral density and load at failure.
Results: VLPs required significantly higher forces to cause 2 mm of osteotomy displacement as compared to DBPs. In this cadaveric study, both plates were stable enough to allow immediate use with a 200 N threshold but only the VLP is stable enough with a 400 N threshold. There was no association between bone mineral density and load at failure.
Conclusions: We found a 3.3 mm DBP to have similar strength to previous reports with thinner plates, but overall had lower load to failure than VLPs. DBPs do not support full crutch-based weight bearing in this cadaver model and caution should be exercised when counseling patients with DBP fixation post-operatively.