- Discussion:
- indicated for
comminuted olecranon frx and frx which occur at or distal to the coronoid process;
- if frx extends distally past midpoint of trochlear notch, it no longer represents only a disruption of the triceps
mechanism but also comprimises the stability of elbow in withstanding varus & valgus forces;
- these fractures will be subjected to increase rotational forces that may cause
tension band fixation to fail;
- distance between coronoid process & olecranon must not be shortened by compression of the comminuted fragments;
- always explain to patient beforehand that plate may require future removal;
- Implants:
- w/ pts < sixty years old, consider
3.5-mm AO DCP contoured to fit fractured olecranon following reduction;
- this neutralizes forces across coronoid frx from tip of olecranon to shaft;
- alternatively use
or
3.5 pelvic reconstruction plate;
-
one third tubular is another alternative in compliant patients;
- PreOp Planning:
- if 3.5 DCP or 3.5 pelvic recon plate is to be used, a bending press will be required for contouring;
- Surgical Approach:
-
reduction:
- reduction of olecranon frx is easiest w/ elbow in extension which relaxes the pull of the triceps muscle;
- once reduced, apply towel clamp to frx site;
- consider placing the tips of the two towel clamps in tension band holes;
-
initial fixation:
- frx of olecranon which is distal to midpoint of trochlear notch, if not comminuted, such as oblique frx, is first stabilized w/ lag screws;
- K wires are not enough for lateral support;
- to overcome valgus/varus instability distal frxs, need to be supplemented w/ plate, even if fixed w/ lag screws,
- Plate Fixation: (
3.5-mm AO DCP)
- contour the dorsally applied plate to allow the fully threaded proximal screw to be inserted at 90 deg to the more distal screws;
- the next two distal screws can usually be placed in the proximal fragment, and should be aimed to avoid the proximal screw;
- the next screw should be placed in compression mode;
- if the coronoid process is fractured, skip the overlying screw hole and apply compression to the next most distal screw hole;
- subsequently, a lag screw can be inserted thru the plate (neutral mode) to grab the coronoid fracture fragment;
- Case Example:
- Plate Fixation for Olecranon Nonunion: (from Danziger and Healy 1992)
-
3.5 DCP is contoured to the proximal fragment;
- K wires are used to achieve provisional fixation;
- plate is secured to proximal frx fragment;
- ensure that the plate does not block full extension;
- external compression device is applied, and provisional fixation is removed;
-
lag screws are applied both proximal and distal to the frx line in divergent positions;
- the proximal lag screw is directed across the frx to the coronoid process;
- the distal lag screw is directed across the frx to the olecranon tip;
- Complications:
- inadequate fixation: the proximal fragment was held w/ only a hook plate;
Olecranon fractures. A clinical and radiographic comparison of tension band wiring and plate fixation.
The use of the Zuelzer hook plate in fixation of olecranon fractures.
Treatment of nonunion of olecranon fractures.
Operative Treatment of Olecranon Nonunion.
MB Danziger and W.L. Healy.
J. Orthop. Trauma. Vol 6. No 3. pp 290-293. 1992.
Tension Band Plating for NonUnion of Proximal Ulna and Olecranon.
Healey WL.
Techniques in Orthopedics.
6: 51-54, 1991.
Posterior olecranon plating: biomechanical and clinical evaluation of a new operative technique.
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