ESIN

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 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.

• 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.

Ring fixator wires may be used.

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

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

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

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

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.

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.

Do not introduce the nail through the olecranon.

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

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.

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.

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.

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.

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.

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.

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.

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

The compartment status should be checked within 6 hours.

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.

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

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.

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.

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.

Whilst the child remains in bed, the forearm should be elevated on pillows to reduce swelling and pain.

They should be encouraged to use the arm.

Cast immobilization is not necessary and hinders early recovery of joint movement.

For Monteggia lesions treated with ulnar nailing, the forearm may be immobilized in a cast in the position of maximum stability of the radiocapitellar joint for 2-4 weeks.

Ibuprofen and paracetamol should be administered regularly during the first 4-5 days of injury, with additional oral narcotic medication for breakthrough pain.

If pain is increasing the child should be examined.

The child should be examined regularly, to ensure finger range of motion is comfortable and adequate.

Neurological and vascular examination should also be performed.

Compartment syndrome should be considered in the presence of increasing pain, especially pain on passive stretching of muscles, decreasing range of active finger motion or deteriorating neurovascular signs, which are a late phenomenon.

See also the additional material on postoperative infection.

Compartment syndrome is a possible early postoperative complication that may be difficult to diagnose in younger children.

The presence of full passive or active finger extension, without discomfort, excludes muscle compartment ischemia.

If there are signs of a compartment syndrome:

1. If the child is in a cast, split the cast, along its full length down to skin level.
2. Elevate the limb.
3. Encourage active finger movement.
4. Reexamine the child after 30 min.

If a definitive diagnosis of compartment syndrome is made, then a fasciotomy should be performed without delay.

Discharge from hospital follows local practice and is usually possible after 1-3 days.

The parent/carer should be taught how to assess the limb.

They should also be advised to return if there is increased pain or decreased range of finger movement.

It is important to provide parents with the following additional information:

• The warning signs of compartment syndrome, circulatory problems and neurological deterioration
• Hospital telephone number
• Information brochure

For the first few days, the elbow and forearm can be elevated on a pillow, until swelling decreases and comfort returns.

The arm can be placed in a sling for a few days until the patient is pain free. Many children are more comfortable without support.

Early movement of the forearm should be encouraged as soon as the patient is pain free.

Physiotherapy is normally not indicated.

The first clinical and radiological follow-up depends on the age of the child and is usually undertaken 4-6 weeks postoperatively.

At this point, the child should be able to move the forearm almost fully with some limited rotation caused by callus formation.

AP and lateral x-rays are required.

See also the additional material on healing times.

Nail removal is delayed until the fracture has modelled completely and can be performed as a day case, under general anesthesia.

The nail end in the proximal ulna can often be easily palpated.

In the distal ulna, the nail end may slip under tendons and nerves. This may irritate the soft tissues and make it difficult to palpate the nail tip.

Exposure of the nail end should be performed under direct vision with small retractors.

In most cases, a small bursa has formed. Once this bursa is opened, the end of the nail can be seen.

The nail can be removed with the extraction pliers, or a similar clamp. A strong needle holder is also useful.