Posterolateral (Boyd) approach to the pediatric proximal radius and ulna

Proximal ulnar injuries associated with radial head dislocation or radial neck fractures, can be addressed through a lateral extension of a posterior skin incision.

This combined approach is also suitable for annular ligament reconstruction, a procedure which is rarely required in the acute setting.

This is the ideal approach for the rare fracture where the radial head is fully displaced posteriorly or medially.

This approach can be performed through a posterolateral incision.

Start the incision posterolaterally behind the supracondylar ridge and continue to the lateral border of the ulna.

Extend the incision as far distally as desired as the direct (subcutaneous) approach to the ulnar shaft.

Incise the deep fascia in line with the incision to approach the lateral margin of the ulna.

Posterolateral approach - Superficial dissection

Expose the ulna behind the anconeus proximally and extensor carpi ulnaris more distally.

Posterolateral approach - Exposure of posterior surface of the ulna

Reflect the anconeus anteriorly/laterally after incising its ulnar insertion.

Detach the supinator near its ulnar origin.

Hold the forearm in a pronated position to keep the posterior interosseous nerve away from the surgical field and limit distal dissection.

Posterolateral approach - Exposure of radial head/neck

Elevate the anconeus and supinator muscles, carefully protecting the posterior interosseous nerve, which is within the substance of the supinator. It may be necessary to separate supinator from the oblique cord of the interosseous membrane.

Retracting these muscles exposes the posterior joint capsule over the radial head.

Pitfall: Do not place retractors around the radius as this may injure the PIN.