Executive Editor: Peter Trafton

Authors: Kodi Kojima, Steve Velkes

Proximal forearm 21-C2.1 ORIF

back to skeleton


1 Preliminary remarks top

C2.1 fractures, with olecranon comminution and a radial head fracture, are characteristic of posterior olecranon fracture dislocations (Monteggia variant). Restoration of a stable trochlear notch, including coronoid process if involved, and repair of the radial head are important for restoring elbow stability.

Restoration of elbow stability is the goal of reduction and fixation of these fractures. Usually, the ulnar fracture is addressed first. Radial fracture repair then follows the ulna.

Begin by exposing both fractures. Difficulty in reducing either fracture may be caused by malreduction of the fracture in the other bone.

Stability of the elbow must be confirmed at the conclusion of reduction and fixation. If instability remains, supplementary external fixation may be necessary.

2 Principles of bridge plating top

Preliminary remark

Absolute stability is desirable for articular fractures. However, this may not be possible in multifragmentary fractures of the proximal ulna. Every effort should still be directed at anatomical reduction and absolutely stable fixation of the major articular surface fragments, particularly the coronoid process. Compression will deform the articular surface, so it no longer fits the trochlea. In this situation, the fracture must be bridged without compression to preserve size and shape of the olecranon fossa. Small interfragmentary screws or K-wires may improve stability.


Bridge plating

A bridge plate is analogous to locked intramedullary nail fixation of a comminuted shaft fracture. In multifragmentary fractures of the olecranon, anatomical reconstruction of the articular surface itself is the primary goal. Intermediate, nonarticular fragments do not need to be reduced anatomically. Cancellous bone graft can be used to support the articular fragments and fill defects.

Directly manipulate only the articular fragments. Excessive manipulation of intermediate fragments risks disturbing their blood supply. If the soft tissue attachments are preserved, and the fragments are relatively well aligned, healing is predictable. Alignment of the main fragments can usually be achieved indirectly utilizing traction and soft tissue tension.

Mechanical stability, provided by the bridging plate, is adequate for indirect healing (callus formation).

3 Reduction top


Through a posterior incision, release the joint capsule medially and laterally at the fracture site. With direct visualization, manipulate and anatomically reduce the articular fragments. Use the distal humerus as a template for reduction. Provisionally fix the fragments with 1.0 mm K-wires.


Reduce the proximal part of the olecranon with pointed reduction forceps and temporarily hold the reduction with one or two K-wires.

Insert all K-wires in a position where they do not interfere with the planned plate and screws.

Control reduction with direct visualization of the sigmoid notch and the posterior cortex of the olecranon, and confirm with C-arm fluoroscopic control.

4 Plate preparation top


Implant choice

Use a 3.5 dynamic compression plate (DCP), reconstruction plate, limited contact dynamic compression plate (LC-DCP), or locking plate (LCP). The reconstruction plate is the least durable, and should be used cautiously as a bridged plate.

Choose the length of the plate so that at least three screws can be inserted in the most proximal fragment and three in the diaphysis.

If the fracture is very proximal or in osteoporotic bone, a preshaped olecranon LCP with locking head screws can be used to allow better fixation.


Plate contouring

Contour the plate to fit the proximal ulna, bending around the tip of the olecranon. Make sure to follow the curvature of the olecranon.

Contouring is done with bending irons and bending press.

5 Proximal plate fixation top

Split the triceps attachment

To achieve close bone plate contact, split the triceps attachment before positioning the plate.


Proximal plate fixation

Anchor the plate with three screws to the proximal olecranon. Make sure that the screws do not protrude into the joint.

Whenever possible, insert the screws bicortically, aiming the drill to the lateral or to the medial cortex.

6 Distal plate fixation top


Distal plate fixation

Insert three bicortical screws in the distal fragment and in a divergent pattern.

Make sure to maintain contour and size of the olecranon’s articulation.


Bone graft

Large defects may be filled with bone graft.

7 Possible fixation of a large coronoid fragment top


Reduction of a large coronoid component of multifragmentary proximal ulna fractures can often be done through the fracture site. Provisional or definitive fixation can be placed at that time, but sometimes it helps to use a screw through a posterior plate for its fixation, as shown here. Insert this as a lag screw, as perpendicularly as possible to the fracture plane at the base of the coronoid. Smaller diameter screws may be better. 

Further details of coronoid fixation

For further information on the fixation of coronoid fractures, see "Repair of coronoid fracture".

8 Pearl - Segmental resection top


In elderly patients, low demand patients, and/or severe osteoporotic bone, it may be possible to excise intermediate bone fragments. The elbow joint must be stable. Collateral ligaments, coronoid process, and distal olecranon surface must be intact.  


The proximal olecranon should be rotated so its articular surface fits the trochlea, recreating an olecranon fossa. Fix with a tension band wire.

v1.0 2007-10-14