Biomechanical Comparison of Proximal Radius Locking Plates Under Dynamic Loading
Proximal radius fractures are commonly encountered in general orthopaedic and upper extremity subspecialty practices. The surgical treatment of these fractures includes the anatomical reconstruction and stable fixation of the proximal radius to achieve early recovery of elbow function, reducing the complication rate. These goals are often obtained in cases showing no or minimal comminution. However, due to high complication rates in the management of complex and highly comminuted fractures, locked plating systems are being utilized with increasing frequency. Specifically, 20% of all elbow trauma is associated with radial head/neck fractures, which historically has been treated with excision or prosthetic replacement. Further, recent literature advocates radial head preservation whenever possible in young, active patients. This study compares the biomechanical properties of two proximal radius locking plate designs under dynamic loading to determine their ability to withstand the forces which occur during fracture healing and early postoperative rehabilitation.
Biomechanical Properties of Fixed-Angle Volar Distal Radius Plates Under Dynamic Loading
Distal radius fractures are commonly encountered in general orthopaedic and hand subspecialty practices. Most surgeons are comfortable with both operative and nonoperative management of these fractures. Treatment options have evolved with fracture pattern governing the specific treatment modality. Casting with or without reduction, percutaneous pinning, external fixation, and open reduction with internal fixation employing dorsal, volar and fragment specific plates are all common methods used to treat these injuries. A paradigm shift has occurred in the treatment of dorsally displaced distal radius fractures. Previous volar plating techniques demonstrated a high failure rate when compared to distal buttress plating which prevented fracture settling and recurrent displacement. Orbay and others have developed volar plating constructs, which provide subchondral support to the distal radius, transferring radiocarpal forces experienced in the postoperative period to the plate and volar cortex. Previous studies have examined biomechanical differences between dorsal and volar plating while further investigations between specific volar plate constructs under static and dynamic loading conditions have been reported. This study compares the biomechanical properties of eight different fixed-angle volar distal radius plate designs under dynamic loading to determine their ability to withstand the forces which occur during fracture healing and early postoperative rehabilitation.
Scaphoid Fracture Repair: A Biomechanical Comparison of Contemporary Cancellous Bone Screws
Scaphoid fractures are common, but often challenging to treat. Clinic studies have demonstrated that both conservative treatment and internal fixation have successful long-term results with the latter providing earlier recovery of motion, decreased immobilization an dearly return to activity. Additionally, internal fixation is indicated as the preferred treatment for displaced or unstable scaphoid fractures, nonunions and late presenting fractures. Many surgeons have also advocated internal fixation for the treatment of acute nondisplaced fractures. Cancellous screw fixation of the scaphoid is one of the more popular and effective methods of treatment, as evidenced by the number of designs available to the orthopaedic surgeon. However, the clinical success of internal fixation is highly dependent upon the ability of the screw to obtain initial compression across the fracture site and its retention, under physiologic loading. This study compares the performance characteristics of seven, contemporary, scaphoid screw designs.