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Adult Humeral Inter-condylar Fractures: Restoration of Frx Anatomy

- Technique:
     - it is helpful to have the patient paralyzed during the reduction (requires general anesthesia);
     - anatomic reduction of the condyles is performed first;
     - remember that the  common factor in fixation failure in these fractures is comminution and/or osteoporosis;
     - best-fit method:
            - first align the fragments that allow an easy anatomic reduction, and then move on to more difficult fracture fragments;
            - remember that errors in reduction will magnify errors in the final result, and therefore it is essential to begin with fragments that have a true anatomic reduction;
     - articular anatomy:
            - goal is to restore of articular anatomy as well as medial & lateral column, and the trochlea;
            - note that the articular surface of the distal humerus is tilted anteriorly 30 deg;
            - articular surface is provisionly held with K wires;
            - provisional reduction is performed using inside out technique to place K wires under direct vision thru exact centers of trochlea and capitellum;
            - capitellar and coronal shear frx
            - under some circumstances, herbert screws or interfragmentary screws are required to achieve reduction, but these should not  interfere w/ lag screw placement;
            - remember that the anterior articular surface is critical for elbow function, and therefore anterior reduction is more important than posterior reduction;
            - remember that the medial column is more important than the lateral column;
            - small 45 k wires not only can be used for reduction, but they can also be cut and left in place for additional fracture stabilization;
     - no man's land: (olecranon and coronoid fossa);
            - coronoid and olecranon fossa must not be violated with fixation;
            - its essential that screws and k wires be directed away from the olecranon and coronoid fossa, as these will block elbow rom;
     - lag screws or positioning screws:
            - see lag screw theory:
            - may be placed either thru the plate or independently to provide fixation;
            - consider using a 4.0 cancellous lag screw to obtain interfragmental compression;
                   - width of the trochlea be narrowed by overcompressing the condyles;
            - an alternative is to insert guidewires (for cannulated lag screws) from the medial condyle into the lateral condyle and from the distal-medial aspect
                   of the medial condyle up into the medial column;
                   - following guidewire insertion, a flexible plate template can be applied to the surface of the bone;
                   - in this manner the plate will be contoured w/ the position of the guide wires in mind;
            - comminution:
                   - when comminution is present, consider using a fully threaded (non lagged) to hold the reduction w/o narrowing the trochlear width;
                          - narrowing of trochlea will cause incongruenty;
                   - bone grafts are used to fill any gaps and prevent narrowing;
                   - take care that no piece of internal fixation encroaches on olecranon fossa;
                   - ref: Reconstruction of a Severe Open Distal Humerus Fracture With Complete Loss of Medial Column by Using a Free Fibular Osteocutaneous Graft

- Restoration of the Extra-articular Anatomy:
     - it is helpful to have the patient paralyzed during the reduction;
     - often reduction is facilitated by flexion/extension and pronation/supination of the forearm;
     - an antomic reduction of the exra-articular anatomy is achieved w/ bone holding clamps;
     - lag screws will help achieve an antomic reduction and will also allow maintenence of the reduction once the bone holding clamps are 
             removed (which is necessary to allow for accurate contouring of the plates)
     - metaphyseal comminution:
             -
note that fracture failure will occur at the metaphyseal level;
             - w/ insufficient bony contact, consider shortening of the humerus at the metaphyseal fracture site;
             - need to maintain alignment;

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A paradigm shift in the surgical reconstruction of extra-articular distal humeral fractures: Single-column plating.