A Volar Locking Plate With Fossa Specific Fixation Provides Comparable Stability Between Articular and Nonarticular Cadaveric Models of Distal Radius Fracture

Abstract

Background: Distal radius fractures often present with a 3-part articular fragmentation pattern, with separation of the dorsal and volar lunate fossa. The column concept of distal radius fixation addresses the importance of stabilizing both the scaphoid fossa lateral column and the lunate fossa intermediate column. Recent evidence strengthens the value of immediate postoperative mobilization. Satisfactory outcomes following these protocols are predicated on volar locking plates (VLPs) providing adequate stability to the fracture repair. We hypothesize that a VLP which individually supports both lateral and intermediate distal radius columns may provide comparable stability between articular and non-articular cadaveric fracture models under parameters meant to simulate postoperative loading. Methods: Eleven cadaveric matched pair specimens were randomized to receive a simulated AO Type A2 non-articular distal radius fracture on one side with an AO Type C3 articular fracture on the contralateral side. Stiffness during cyclic loading was compared between fracture groups. A matched-paired Student t-test was used to determine statistical significance ( P = .05). Results: There were no significant differences ( P = .35) in stiffness between the articular models (mean 370.0 N/mm, +/-93.5) and the non-articular models (360.4 N/mm, +/-60.0) of distal radius fracture. Conclusion: A VLP that individually supports the scaphoid and lunate fossa with fixed angle subchondral support may provide comparable fixation strength with resistance to displacement between articular and non-articular fracture patterns. The current results suggest that fossa-specific VLP fixation in articular fractures can maintain construct stability during postoperative loading.