A MedStar study comparing the load-to-failure and stiffness associated with differing surgical techniques in the repair of elbow fractures was published in The Journal of Hand Surgery. In “Fixation of Regan-Morrey Type II Coronoid Fractures: A Comparison of Screws and Suture Lasso Technique for Resistance to Displacement,” the authors compared the results between screw fixation and suture lasso fixation in cases of coronoid fractures.
The research team at the Curtis National Hand Center at MedStar Union Memorial Hospital included Nicholas P. Iannuzzi, MD; Adrian G. Paez, BS; Brent G. Parks, MSc; and Michael S. Murphy, MD.
Coronoid fractures most commonly occur in tandem with complex elbow dislocations. This type of fracture accounts for less than 2% of all elbow fractures but has been identified in 10% of elbow dislocations. In the Regan and Morrey classification system, based on the height of the coronoid fragment, Type II fractures are 50% or less.
The study team performed a biomechanical study using 10 pairs of cadaveric elbows, which were randomized to receive either a screw fixation or suture lasso fixation. The load to failure and stiffness were then measured using a material testing machine.
The authors found that screw fixation provided greater strength and stiffness than suture lasso fixation. They concluded that when feasible, screw fixation may provide greater resistance to displacement of the coronoid compared with the suture lasso technique.
While this research was conducted with a small sample, it is clinically relevant, as other researchers have reported a higher rate of failure after screw fixation. For type II coronoid fractures, screw fixation may provide a stronger fixation construct for fractures of adequate size to support a screw. Future research may consider the use of multiple, smaller screws for fixation and the role that soft tissue structures, particularly the anterior capsule, have in imparting elbow stability after terrible triad injuries of the elbow. The authors wrote that “where feasible, the improved biomechanical stability imparted by screw fixation supports the use of screws in Regan-Morrey type II coronoid fractures in the setting of unstable fracture dislocations about the elbow.”
The Journal of Hand Surgery, 2017. DOI: 10.1016/j.jhsa.2016.11.003
