Executive Editor: Peter Trafton

Authors: Kodi Kojima, Steve Velkes

Proximal forearm

back to skeleton

Glossary

Posterior approach

Preliminary remark

A number of fracture patterns of the proximal forearm can be addressed using this approach. The more complex the fracture configuration, the more extensile the approach must be.


enlarge

Skin incision

The ulna is a subcutaneous bone. Start the incision a few centimeters proximal to the tip of the olecranon, as needed for access to the injured area. Curve slightly medially around the tip of the olecranon, and go distally for a few centimeters, as needed to provide access to the injured area.

Note
In case of associated radial head fracture the incision can be made distally along the lateral border of the proximal ulna.


enlarge

Surgical dissection

Elevation of the lateral flap provides access to the lateral structures of the elbow. In the proximal portion, dissect and elevate the subcutaneous tissue. Over the olecranon, remove the olecranon bursa and incise the triceps aponeurosis exposing the bone.

Behind the medial humeral epicondyle, identify and protect the ulnar nerve.

Detach the flexor carpi ulnaris tendon on the medial side, and the anconeus tendon on the lateral side as far as necessary to expose the involved articular surfaces and for an anatomical reduction and stable fixation. Some coronoid fractures can be addressed through the lateral extension of this approach, particularly with the elbow dislocated, and/or with displacement of a proximal radius fracture.


enlarge

Distal extension

For proximal ulna fractures extending into the diaphysis, the posterior approach can be extended distally as far as necessary. Carefully detach the muscle origins (anconeus, flexor carpi ulnaris and extensor carpi ulnaris) from the ulna as needed to reduce and fix the fractures.

The posterior ulna lies in an internervous plane between the ulnar and radial nerves.


enlarge

Lateral extension

In proximal ulna injuries associated with radial head fracture, both can be addressed through a lateral extension of the posterior incision.

The incision should start 7 cm proximal to the tip of the olecranon.

The decision to detach the anconeus muscle from the ulna depends on the necessity to address a fracture of the radial head, or neck, or a fracture of the proximal ulna involving the sigmoid notch.

In a combined, simple proximal ulnar and radial fracture it may not be necessary to detach the anconeus. The proximal radial fracture may be approached by dissecting and elevating the subcutaneous tissues laterally exposing the septum between the anconeus and the extensor carpi ulnaris muscles (see lateral approach).


enlarge

Osteotomy of the lateral humeral epicondyle

A variation for lateral exposure with preservation of collateral ligaments and extensor tendon origin involves osteotomy of the lateral humeral epicondyle.


enlarge

The soft tissues and epicondyle are reflected anteriorly to provide access to the proximal radius and ulna.

Repair after this approach requires fixation of the epicondyle. The necessary screw hole can be drilled before the osteotomy.


enlarge

Medial extension

In fractures of the olecranon combined with a type II or III coronoid fracture, both can be addressed through a medial extension of the posterior incision.

The incision should start 7 cm proximal to the tip of the olecranon.

Dissect and isolate the ulnar nerve.

Elevate the subcutaneous flap medially and expose the septum between the pronator teres and the common flexor tendon.

Dissect the space between these muscles and elevate and free them from the elbow joint capsule.

A longitudinal arthrotomy may be extended as necessary to expose the proximal ulna.


enlarge

Osteotomy of the medial humeral epicondyle

A variation for medial exposure with preservation of the medial collateral ligament and common flexor origin involves osteotomy of the medial humeral epicondyle. The soft tissues and epicondyle are reflected distally to provide access to the medial elbow joint and proximal ulna.


enlarge

Repair after this approach requires replacement and fixation of the epicondyle. The screw hole can be drilled before the osteotomy.

v1.0 2007-10-14