Executive Editor: Chris Colton

Authors: Dominik Heim, Shai Luria, Rami Mosheiff, Yoram Weil

Forearm shaft 22-B3 Compression plating

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Glossary

1 General considerations top

General considerations enlarge

In the past, wedge fractures have usually been fixed rigidly. The underlying principle focused on mechanical issues, not on biology. Today, biology takes precedence and for this reason not all wedge fragments are incorporated rigidly into the fixation.
Small wedge fragments that do not have a significant effect on stability should not be addressed (they will become incorporated into the fracture by indirect bone healing). Larger wedge fragments that contribute to the stability of the fixation, are fixed to one main fragment. Sometimes, fixation of the wedge to one main fragment helps reduction of the residual fracture.
If a lag screw is inserted separate from the plate, a 2.7 mm screw is often used, depending on the size of the bone, for biological reasons, and to reduce the risk of splitting the wedge.
If a lag screw is inserted through a 3.5 mm plate, a 3.5 mm screw should be used.


Note on approaches

When both bones need to be reduced and fixed, a separate approach to each bone should be performed in order to reduce the risk of heterotopic bone formation.

For proximal radial shaft fractures, the anterior approach (Henry) is most often used to minimize the risk of damage to the posterior interosseous nerve, which crosses the proximal radius within the supinator muscle.

In mid and distal radial shaft fractures, either the anterior approach (Henry) or posterolateral approach (Thompson) can be used, depending on surgeon’s preference.

The ulna is exposed by the standard subcutaneous approach between the flexor and extensor muscle compartments.

2 Principles top

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Order of fixation

Normally, the simpler of the two fractures will be approached first and preliminary fixation undertaken. If both bones have similar fractures, then the ulna will normally be addressed first.

Most often, fixation of fractures involving both bones proceeds as follows:

  1. Reduction and preliminary fixation of the simpler fracture (B3.1, B3.2). In the case of wedge fractures of both bones (B3.3) start with the bone with the smaller wedge
  2. Reduction and definitive fixation of the other bone
  3. Definitive fixation of the first bone

Never commit yourself to the definitive fixation of one bone until you have assured yourself that you can reduce the other bone.

If a reduction of the second bone is impossible, the preliminary fixation of the first bone has to be loosened and the other bone reduced and fixed. The first bone is then restabilized.

This illustration shows a B3.2 fracture (simple ulnar fracture, radial wedge fracture) in which preliminary fixation of the simple ulnar fracture would be the first step.

Throughout this module, the fixation of each bone will be described to completion but the surgeon is reminded not to complete the first fixation until the second bone has been definitively fixed.

3 Detailed procedures top

Detailed procedures enlarge

B3.1

Required steps are:

  1. Preliminary fixation of oblique radial fracture, or preliminary fixation of transverse radial fracture
  2. Definitive fixation of the ulnar wedge fracture
  3. Completion of radial fixation and check of osteosynthesis

The required techniques are:


Detailed procedures enlarge

B3.2

Required steps are:

  1. Preliminary fixation of oblique ulnar fracture, or preliminary fixation of transverse ulnar fracture
  2. Definitive fixation of the radial wedge fracture
  3. Completion of ulnar fixation and check of osteosynthesis

The required techniques are:


Detailed procedures enlarge

B3.3

Required steps are:

  1. Preliminary fixation of the ulnar wedge fracture
  2. Definitive fixation of the radial wedge fracture
  3. Completion of fixation of ulnar wedge fracture and check of osteosynthesis

The required techniques are:

4 Check of osteosynthesis top

Check of osteosynthesis enlarge

Check the completed osteosynthesis by image intensification. Make sure that the plate(s) are at proper locations, the screws are of appropriate length and a proper reduction was achieved.


Check of osteosynthesis enlarge

The elbow should be stabilized at the epicondyles and the forearm rotation should be checked between the radial and ulnar styloids.

5 Assessment of Distal Radioulnar Joint (DRUJ) top

Before starting the operation the uninjured side should be tested as a reference for the injured side.

After fixation, the distal radioulnar joint should be assessed for forearm rotation, as well as for stability. The forearm should be rotated completely to make certain there is no anatomical block.


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Method 1

The elbow is flexed 90° on the arm table and displacement in dorsal palmar direction is tested in a neutral rotation of the forearm with the wrist in neutral position.

This is repeated with the wrist in radial deviation, which stabilizes the DRUJ, if the ulnar collateral complex (TFCC) is not disrupted.


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This is repeated with the wrist in full supination and full pronation.


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Method 2

In order to test the stability of the distal radioulnar joint, the ulna is compressed against the radius...


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...while the forearm is passively put through full supination...


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...and pronation.

If there is a palpable “clunk”, then instability of the distal radioulnar joint should be considered. This would be an indication for internal fixation of an ulnar styloid fracture at its base. If the fracture is at the tip of the ulnar styloid consider TFCC stabilization.

v2.0 2013-07-09