General Editor: Chris Colton

Authors: Fergal Monsell, Dalia Sepulveda

Pediatric distal forearm 23-M/3.2

back to Pediatric overview

Glossary

1 Introduction top

enlarge

These fractures are usually posteriorly angulated (apex anterior) and can generally be reduced closed, ideally under general anesthesia. Impediments to reduction are interposed periosteum and pronator quadratus.

Fractures with an intact dorsal periosteum are stable after reduction and may not require wire fixation. K-wire stabilization may be strongly indicated in some cases.

Anteriorly angulated (apex posterior) fractures are less common and are also generally reduced closed. Impediments to reduction are the extensor tendons.

2 Reduction top

enlarge

Indirect reduction of completely displaced fractures

In these rare multifragmentary fractures, the standard reduction maneuvers are unlikely to be successful. Reduction relies largely on longitudinal distraction with direct manual pressure over the displaced distal fragment.

Failure to achieve a stable reduction is a strong indication for internal fixation using K-wires and accepting some residual displacement, in anticipation of subsequent fracture modelling.

3 K-wire fixation top

enlarge

General considerations

For fractures that are unstable after reduction, single, or crossed, K-wires are normally sufficient to stabilize the fracture.

Occasionally a further wire is used to stabilize the ulna.


enlarge

Approaches

A small skin incision is made.

The incision is deepened to the bone using a blunt artery forceps and a protective sleeve is inserted.

Care should be taken to avoid the dorsal sensory branch of the radial nerve and the dorsal sensory branch of the ulnar nerve.


enlarge

For a posteriomedially inserted second wire, a mini-open approach is used and a guide is required to protect the posterior soft tissues, particularly the extensor tendons.


enlarge

K-wire insertion

A single, or two crossed, smooth 1.6 mm K-wires are inserted through the radial metaphysis, avoiding the growth plate and the perichondrial ring.

The wires should be inserted with an oscillating drill and cooled with saline solution to prevent thermal injury.

The wires may also be inserted by hand using a T-handle.

Ideally, wires are inserted using image intensification control, in order to check the trajectory of the wire and to ensure engagement of the far cortex without penetration of the soft tissues.


enlarge

Pearl: For more distal fractures, it is occasionally necessary to insert antegrade wires engaging the distal radial metaphyseal flare.

The insertion incisions should be deepened to bone by spreading the tissues using a blunt artery forceps. The wires should be passed through protective guides.

Care should be taken that the wires do not damage the perichondrial ring of the physis.


enlarge

An alternative in more distal radial fractures is to insert the wire through the radial styloid and across the radial physis. If this is undertaken, it is especially important to avoid thermal injury.


enlarge

Occasionally a second wire is used to stabilize the ulna. 


enlarge

The K-wires are left protruding through the skin, bent and cut. The skin is protected with sterile padding prior to the application of a cast.

The illustration demonstrates the use of a small section of plastic tubing over the cut ends of the protruding wires. This adds further protection for the skin.

Note: Excessive pressure between dressing and skin should be avoided to prevent skin necrosis.

4 Short arm cast top

enlarge

General considerations

The purpose of the cast is protective and for pain relief, as stability is provided by the K-wire(s).

The short arm cast is applied according to standard procedure:

Note: In young, small, or noncompliant patients, it is safer to apply a long arm cast.


enlarge

Splitting of cast

If a complete cast is applied in the acute phase after injury, it should be split over the full length of the cast. The split of the cast must be full thickness and expose the underlying skin.

5 Long arm cast top

enlarge

In the event that a long arm cast is necessary (see above) it is applied and split according to standard procedure.

v1.0 2016-12-01