External fixation is mostly used as a temporary fixation awaiting definitive internal fixation.

Temporary external fixation is recommended when definitive stabilization and/or immediate soft tissue coverage cannot be performed at the time of primary surgery.

In resource-limited settings, external fixation may be the best available option for fracture fixation. When adequately applied and handled with appropriate aftercare, it can serve as definitive treatment.

Definitive fixation with an external fixator for practical tips on strengthen a external fixation system so it can function as definitive fixation.

Indications for temporary external fixation

Consider external fixation in the following situations:

1 When there are no possibilities for (direct) definitive fixation. 

2 When the systemic condition of the trauma patient only allows short (damage-control) surgery.

3 High risk of infection:

• Contaminated wounds - e.g. Farm injuries, road accidents with dirt, feces, or water contamination.
• Heavily contaminated fracture site - Where immediate internal fixation could seed infection.
• Delayed presentation - More than 6–8 hours after injury.

4 Severe soft tissue damage:

• Compartment syndrome - Risk of compartment syndrome development.
• Extensive soft tissue injury - e.g. De-gloving, muscle crushing, skin loss.
• Delayed coverage/closure - Wounds that require delayed flap coverage or delayed skin closure.

Advantages of temporarily external fixation

Applying an external fixator provides a stable construct that:

• Prevents fracture site displacement
• Reduces pain
• Lowers fracture-related infection risk
• Allows proper wound care and give soft tissues the opportunity to heal or to demarcate the borders of necrotic tissue

According to the BAPRAS/BOA guidelines, if exchange from external fixation to internal fixation is planned, this should be done as early as possible – preferably within 72 hours of the primary debridement and in the same procedure as definitive soft tissue coverage.¹

Approaches

There are different techniques to provide temporary stability with an external fixation. Many different types and brands of external fixators exist with varying complexities, but the techniques described can be simplified.

We prefer modular external fixation (with a bar-to-bar construct) over a single bar technique and a setting with limited skills available, as it enables easier and better fracture reduction and can be universally applied to different fracture patterns.

Modular external fixation

Synonym = bar-to-bar fixation

The basic principles of modular external fixation technique are:

1 On each side of the fracture, two pins are placed

2 The pins on each side are interconnected with a bar and clamps

3 The two bars on each side of the fracture are then connected with another bar and clamps bridging the fracture

Variations are recommended for different fracture locations and patterns. However, the key feature of a modular external fixation is that it provides stable support for the fractured bone and can be easily adjusted for length, angulation, and position.

Modular external fixation

See Tibia Shaft to read the story of a 62-year-old man who sustained an open fracture of the left tibia and was treated with a external fixator.

Single bar fixation

Synonym = linear fixation

In single-bar constructs, pins are placed all in one plane and connected by a single bar. This configuration provides limited stability and makes adequate alignment of the bones more challenging, As a result, the risk of malunion is higher.

The only practical advantage of single-bar fixation is that it requires fewer components (bars and clamps). Therefore, when resources allow, modular external fixation is preferred, as it provides better control of alignment.

Single bar fixation

Damage Control Surgery External Fixation

In the setting of damage control surgery (DCS), external fixation is the preferred method for temporary stabilization of fractures in severely injured patients. Temporary external fixation provides rapid stabilization of long-bone fractures, which helps control hemorrhage, reduces pain, and facilitates ongoing resuscitation and management of associated injuries. Furthermore, external fixation allows access to soft tissues for wound care and simplifies nursing and intensive care management of polytrauma patients.⁴

Principles with priority in Damage Control Surgery: 

• Procedures should be performed as quickly as possible to minimize operative time, reduce additional blood loss, and limit the physiological burden on the patient, allowing the patient to return promptly to the intensive care unit for continued resuscitation.
• Strategic pin placement with anticipated surgical approaches in mind. In general, pins are preferably inserted in the anteroposterior direction, as definitive fixation methods such as intramedullary nails and plates are commonly applied through lateral or medial approaches.

Certain technical principles of definitive external fixation are less critical in the damage control setting:

• Pin placement through muscular compartments within recognized safe zones may be acceptable if it facilitates rapid stabilization (e.g., transfixing the quadriceps muscle in the femur)
• Self-drilling pins may be inserted without pre-drilling to save operative time, even though this may theoretically increase the risk of thermal necrosis and later pin loosening
• Pins may be placed closer together, for instance by using multipin clamps, prioritizing speed of application over maximal construct stability. A multipin clamp in essence functions as a bar on one side of the fracture.

Definitive fixation is generally expected to be performed within approximately one to two weeks after damage control surgery, once the patient has been physiologically stabilized. Current evidence suggests that conversion from temporary external fixation to definitive fixation within this timeframe does not significantly increase the risk of infection due to pin tract colonization.^5,6

Typical examples of temporary DCS constructs include:

Resources required

The absolute minimum resources needed for a modular construct are:

• Trauma/orthopedic instrument tray - suitable for adequate debridement and reduction  
• Drill – preferably sterile or with a sterile cover; non-sterile is inferior but possible if an assistant is skilled in drilling
• Threaded pins – at least 4 of sufficient length and diameter
• Bars – at least 3 of sufficient length
• Clamps – at least 4 pin-to-bar clamps (that fit the diameter of the pin and bar of your set), and 2 bar-to-bar clamps (that fit the diameter of the bar of your set)
• Drill bit – preferably 3.5mm for a 5mm pin
• Tissue protector - tissue protector or drill sleeve of the same diameter as the pins inserted (preferably a 5mm drill sleeve with 3.5mm insert to pre-drill through the insert first)
• Blades – preferably both a size 11 (for stab incisions for the pins) and a size 21-24 (for debridement and larger incisions)
• Artery forceps - to dissect to the bone after skin incision for the pin has been made
• Fluid - sterile fluid to cool during pre-drilling
• T-wrench - or hand drill for manual insertion of the pins
• (Allen) key - the right type of key to tighten the clamps

The minimal amount of external fixation materials needed to perform a basic bar-to-bar frame.

External fixation of a tibia shaft fracture: step-by-step

We present here the basic steps of applying a modular external fixation for a tibial shaft fracture. Other fracture locations may require adaptions to these steps.

1 Preparation

Before starting the procedure:

• Imaging - use imaging techniques, such as X-rays, to precisely visualize the fracture and the surrounding anatomy. Have the images readily available in theatre.
• Marking - draw important landmarks and proposed pin locations on the skin. This step ensures accurate placement of pins and improves progress of the procedure.

2 Debridement and preliminary reduction

Prior to pin insertion, perform debridement and initial reduction, either open or closed. This involves grossly aligning and restoring the fractured bone fragments to their anatomically correct positions.

Performing surgical debridement

3 Pin placement

This step involves selecting the pins, choosing a location, making an incision, pre-drilling, measuring pin length, and placing the pins.

A. Select pins

• Diameter: The rule of thumb is that the diameter of the pin should not extend 1/3 of the diameter of the bone. In general 5mm pins are appropriate for the femur and tibia (if the bone allows a 6mm pin it will increase the stability of the construct). For smaller diameter bones, such as the metatarsal bone, a 4mm pin is appropriate.
• Length: The length of the pin depends on the diameter of the bone and the amount of soft tissue. Choose a pin that can span both cortices with its threaded part.
• Type of tip: You can choose from self-drilling, blunt, or sharp pins. We always advise to pre-drill, because any type of threaded pin can be inserted, as long as they are straight. If intra-operative imaging is not available, the safest option is to select a blunt pin.

Six of the various types of pins available

B. Location
Plan ahead where the pins will be placed:

• Outside of the zone of injury.
• In the safe zones of a bone. Inserting pins percutaneously through safe zones reduces the risk of damage to neurovascular structures.²
• Place one pin as close to the fracture as possible, while maintaining a distance of two fingerbreadths from the fracture site.
• Place a second pin as far from the fracture as possible, in strong, healthy bone, in an area with adequate cortical thickness (diaphyseal bone).

When choosing the pin locations, use the safe zones and take into account possible soft tissue reconstruction strategies.

C. Incision
Make a stab incision of around 1cm and dissect bluntly to the bone, for example with artery forceps. Place the tissue protector on the bone. Make sure there is no tissue in between.

Tip - For a 5mm pin use a tissue protector or drill sleeve of 5mm with a 3.5mm insert (5.0/3.5). After drilling, remove only the insert to keep track of the location of the pinhole, and insert the pin through the tissue protector. Then remove the trocar B 3.5mm and the drill sleeve.

D. Pre-drilling
Pre-drill your pins with a sharp drill bit, even if they are self-drilling. Drill on high speed, and cool with sterile fluids (saline) during the drilling. Drill through both cortices, but prevent protruding too far to avoid iatrogenic damage to important structures on the opposite side.

We advise to pre-drill and after that manually insert the pins instead of direct insertion of a self-drilling pin because of the following reasons:

1. Thermal injury. Excessive temperature at the bone–pin interface can cause thermal necrosis, which may contribute to pin loosening or infection³.
2. Bone purchase, might be better with pre-drilled pins.
3. One technique that is always applicable irrespective of the types of pins available.

In damage-control setting when an external fixator is left in place only temporary, direct insertion of pins is acceptable and commonly used. However, in practice in lower-resource settings external fixators are left in place for longer time and techniques used are often suboptimal.

Tip - If you drill on a sloping surface (such as the medial side of the tibia), first point the tissue protector and drill perpendicular to the surface, then adjust the drill to the intended direction as soon as the drill bit has entered the bone.

E. Pin length measurement
A pin should always be placed bicortically. 

A few example methods are listed here to measure or estimate the depth a pin should be inserted when intra-operative fluoroscopy is not available:

• Using a depth gauge after pre-drilling and mark the depth on the pin. Marking on the pin can be done for example with a sterile marker, a dot of blood or by tying a ligature.
• If a depth gauge is unavailable, you can estimate the pin length by stopping to dril when you hit the second cortex (it is the moment you feel more resistance again). Mark the drill length that is inside the bone and add 5mm, as a surrogated for the thickness of the second cortex. This length indicates how far the pin needs to be inserted into the bone. Mark it on the pin you will insert.

F. Pin placement
Use a T-wrench to manually place your pins until they reach the measured depth.

4 Build the construction

Connect the two pins on one side of the fracture using a bar and two pin-to-bar clamps. The clamps should be, by estimation, two finger-breadths away from the skin as the optimum between the possibility for soft tissues to swell and optimal construct strength. Securely tighten these clamps.

Repeat this on the opposite side of the fracture.

Connect the two bars with a third bar that bridges the fracture. Do not yet tighten it fully to facilitate definitive fracture reduction.

5 Definitive reduction

Perform fracture reduction and compression. The surgeon maintains the reduction while the assistant tightens the clamps.

6 Check the construct

• Clamp tightness - Check tightness of all the clamps with the key.
• Skin tension - There should be no skin tension around the pins, otherwise skin infection will occur. If there is tension, consider elongating the incision around the pins longitudinally. 
• Pin tract coverage - Turn a gauze around the pin where it exits the skin. Consider dripping povidone over the gauzes.

Aftercare

Here we describe general points for aftercare after external fixation. Specific considerations for fractures types and soft tissue reconstructions apply.

Monitoring

Close monitoring of the lower leg is essential during the first 48 hours after surgery to rule out compartment syndrome. Keep the leg elevated during this period. Patients with open fractures are at high risk, and compartment syndrome may still develop despite the presence of an open wound.

Regular monitoring of the external fixator site for signs of infection, swelling, or other complications, including pain levels, is crucial.

Effective pain reduction is achieved through both bone stabilization with the external fixator as well the use of the reverse WHO pain ladder, as described in pain management.

Wound and pin care

Wound care is a critical part of open fracture treatment. If dedicated wound nursing is available, their specialized attention addresses potential complications.

For the initial week post-surgery, daily pin care ensures a closely monitored healing trajectory, transitioning to every other day as the wound stabilizes. Gauze with iodine acts as a protective barrier, preventing infections and maintaining a sterile environment. Regular pin flushing further reduces the risk of microbial colonisation. 

Performing wound care

Physiotherapy

Early, non-weight-bearing mobilization is recommended as soon as soft tissues permit, balancing the need to prevent stiffness. Adjacent joints should be trained as soon as possible to prevent flexion or extension lag. Also make sure that patients keep their ankle in a 90 degree position to prevent equinus foot deformity.

Complications of fracture management in open fractures