Ortho-Preferred

Percutaneous Pinning of Distal Radius Fractures - Clinical Outcomes

           - w/ the distal radius in a reduced position, percutaneous K wires are inserted, and then the distraction is released and the wrist is taken out of flexion;
           - in the study by Dunning CE et al, the authors investigated the changes in fracture stability when using supplemental radial styloid pinning in combination with external fixation;
                  - 8 previously frozen cadaveric upper extremities were mounted in a computer-controlled wrist-loading apparatus;
                  - this device was used to generate finger and forearm motions through loading relevant tendons.
                  - unstable extra-articular distal radius fracture was simulated by removing a dorsal wedge from the distal radius metaphysis;
                  - electromagnetic tracking system measured fragment motion following randomized application of a Hoffman external fixator, a Hoffman external fixator with 2 supplemental radial styloid pins, and a dorsal 3.5-mm AO plate;
                  - addition of radial styloid pins to a construct stabilized by an external fixator significantly improved fragment stability, approaching that achieved with the dorsal AO plate;
                 - Supplemental pinning improves the stability of external fixation in distal radius fractures during simulated finger and forearm motion 
           - in the report by Wolfe SW, et al, the authors simulated unstable extra-articular distal radius fractures were created in 7 fresh-frozen cadaveric upper extremities and stabilized using 4 different external fixators;
                  - physiologic muscle tension across the wrist was simulated by application of 40-N load distributed among the wrist tendons;
                  - fracture stability was reassessed for each of the constructs after augmentation of the fracture fragments with a single dorsal transfixion K-wire;
                  - K-wire augmentation demonstrated a significant reduction in motion of the distal radial fragment of at least 40% in all 3 rotational planes;
                  - for flexion/extension, the reduction in motion was from 4.5° to 2.6°.
                  - for radial/ulnar deviation, the range of motion decreased from 3.0° to 1.5°.
                  - rotational motion declined from an average of 3.2° to 1.2°.
                  - addition of the single dorsal transfixion K-wire significantly improved stability of each of the 4 fixators in at least 1 of the 3 planes in which motion was measured;
                  - data supported concept of K-wire augmentation for increasing stability of an unstable extra-articular DRF regardless of the type of Ex Fix that is used

                  - A biomechanical comparison of different wrist external fixators with and without K-wire augmentation



 - references:
       - Intraarticular fractures of the distal radius: a cadaveric study to determine if ligamentotaxis restores radiopalmar tilt.

       - Severe fractures of the distal radius: effect of amount and duration of external fixator distraction on outcome.

       - Biomechanical analysis of pin placement and pin size for external fixation of distal radius fractures.

       - Functional outcomes for unstable distal radial fractures treated with open reduction and internal fixation or closed reduction and percutaneous fixation. A prospective randomized trial.



Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Wednesday, February 6, 2013 4:46 pm