Executive Editor: James Hunter

General Editor: Fergal Monsell

Authors: Andrew Howard, Peter Schmittenbecher, Theddy Slongo

Pediatric forearm shaft 22u-D/4.2

ESIN

1. Introduction

General considerations

The ESIN method involves closed reduction and internal fixation with an elastic nail.

This method is a commonly used treatment option for displaced and/or unstable fractures of the forearm and can be used in any age group.

ESIN without image intensifier

ESIN method is possible without an image intensifier or peroperative x-ray examination.

The procedure is modified to include direct visualization of the fracture with an open approach. Stripping of the periosteum and disruption of the fracture hematoma are disadvantages.

2. Instruments and implants

Instrument set for ESIN
  • 1.5-2.5 and occasionally 3.0 mm elastic nails
  • Alternatively: 30 cm long, 1.6-2.5 mm K-wires with the tip bent
  • Awl or drill
  • Inserter
  • Nail cutter
  • Small hammer
  • Optional: end caps

The end cutter is useful to avoid sharp ends and soft-tissue irritation.

Use of K-wires

Ring fixator wires may be used.

Bend the tip by approximately 30° to provide a gliding aid.

Nail diameter

For optimal reduction and intramedullary three-point fixation, the nail diameter should be between 60% and 70% of the medullary canal.

3. Patient preparation

This procedure is normally performed with the patient in a supine position .

4. Technique

Preliminary reduction

Preliminary reduction is not useful as deformity usually recurs following manipulation.

Entry points

The proximal lateral entry point is in common use and shown in this procedure.

The distal medial entry point is an alternative and useful in midshaft and proximal 1/3 fractures of the ulna.

Opening the canal

Use small scissors or a surgical clip and small retractors to dissect to the bone under direct vision.

Place the awl or drill directly onto the bone and perforate the near cortex, under direct vision, perpendicular to the bone.

Do not hammer the awl to avoid perforation of the far cortex.

When the medullary canal is reached, lower the awl or drill 45° to the shaft axis and advance it with oscillating movements to produce an oblique canal.

Pitfall: Entry point through the olecranon

Do not introduce the nail through the olecranon.

This does not enhance fixation and causes troublesome soft-tissue irritation.

Nail insertion

Precontouring the nail for forearm shaft fractures may be required.

The medullary canal is small and the nail may deform during insertion.

Fix the nail into the inserter and pass it into the canal.

Pearl: insertion of nail tip perpendicular to shaft

Insert the nail with the tip perpendicular to the shaft axis until the far cortex is felt. Rotate the nail 180° and advance it using the curved side of the tip as a gliding aid.

If the tip is stuck in the far cortex and cannot be advanced, remove the nail and bend the tip to give a slightly more pronounced curvature.

Advancing the nail

Advance the nail to the fracture site with an oscillating maneuver.

Pearl: A short working length (3-5 cm) between the entry point and the inserter improves control of the nail during insertion.

Pitfall: iatrogenic fracture

In young children, the nail tip may become stuck because of the narrow medullary canal.

Do not use a hammer if the nail is stuck as this risks iatrogenic fracture.

Withdraw by 2 cm, rotate the nail to free the tip and continue advancing.

Reduction with nail

Point the nail tip toward the opposite fracture plane and advance the nail into the floating segment.

Thread the nail through the floating segment.

At this point gentle hammer blows may prevent the nail from advancing into the soft tissues. Rotate the tip to reduce the fracture.

Advance the nail for 2-3 cm and rotate the nail back to the initial position.

Reduction can be aided by increasing the deformity to allow fracture surface contact using the nail as a joystick.

Fracture reduction under direct vision is likely with this configuration.

Closed reduction

If the nail cannot be advanced into the floating segment or distal fragment, manipulate the fracture by distraction and rotation of the forearm and check using image intensifier.

This may reduce the fracture in both planes and allows the nail to advance.

Open reduction

If the nail cannot be advanced after three attempts, open the fracture zone for reduction and advance the nail into the distal fragment under direct vision.

If an image intensifier is not available, an open procedure is necessary.

Make a small skin incision over the fracture zone followed by a small incision in the deep fascia.

The fracture often causes soft-tissue stripping, and the fracture fragments are located with blunt finger dissection.

Insert two small retractors so that both fracture ends are visible.

Pearl: Before opening the fracture, a threaded K-wire may be used to manipulate the proximal fragment.

Pitfall: risk of compartment syndrome

Repeated attempts to achieve closed reduction and fixation may increase the risk of compartment syndrome.

The compartment status should be checked within 6 hours.

Final nail insertion

Advance the nail down to the strong metaphyseal bone at the level of the distal ulna.

Place the forearm in supination with the nail tip rotated towards the radius to tension the interosseous membrane.

Pearl: estimation of nail length

If an image intensifier is not available, estimate the optimum nail length with a second identical nail placed parallel to the initial nail.

Cutting the nail and wound closure

Cut the nail near the bone.

If a dedicated nail cutter is not available, cut the nail slightly shorter as the end will be sharper and this prevents skin perforation.

Gently withdraw the nail by 1 cm, cut the nail outside the skin and reinsert to the original position with an impactor.

Close the subcutaneous tissue and skin in a standard manner. 

5. Option: end caps

End caps may be useful for stabilizing length unstable fractures.

The nail should finally be advanced using the beveled impactor.

A small end cap can be screwed in over the nail using the inserter.

6. Final assessment

Check the completed osteosynthesis with image intensification. These images should be retained for documentation or alternatively an x-ray should be obtained before discharge.

Make sure that the desired reduction has been achieved and the nail is of appropriate length.

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v1.0 2018-11-28