Fracture-Related Infection

What Is Fracture-Related Infection?

Fracture-related infection refers to infection associated with a fracture and its treatment.

It can occur:

• Soon after injury
• After fixation surgery
• During delayed fracture healing
• In association with nonunion
• Months or sometimes longer after the original procedure

Presentation varies considerably.

What Are the Signs of Infection?

Possible findings include:

• Wound drainage
• Redness
• Swelling
• Increasing pain
• Fever
• Wound breakdown
• Exposed implant
• Persistent nonunion
• Recurrent sinus or drainage

However, low-grade infection can sometimes present without dramatic external signs.

How Is Fracture-Related Infection Confirmed?

Some findings can directly establish the diagnosis, while others only raise suspicion and require further investigation.

Findings that may be considered confirmatory include:

• A sinus or fistula communicating with the fracture or implant
• Purulent drainage or pus from the fracture or operative site
• Appropriate microbiological confirmation from separately collected deep tissue samples
• Compatible histological evidence when obtained

Increasing pain, redness, swelling, fever, raised inflammatory markers, suspicious imaging, persistent drainage and failure of fracture healing may support suspicion but are not all individually diagnostic.

ESR or CRP alone cannot confirm or exclude fracture-related infection.

Why Is Deep Tissue Sampling Important?

When operative sampling is required, multiple separately collected deep tissue samples from representative areas are preferred.

Superficial swabs generally do not reliably represent deep implant-associated infection.

Culture strategy and antibiotic timing should be coordinated appropriately.

Why Do Implants Complicate Infection?

Bacteria associated with implants can form biofilm, which can make established implant-associated infection more difficult to eradicate with antibiotics alone.

Whether fixation can be retained depends on factors such as:

• Implant stability
• Acceptable alignment
• Fracture healing status
• Adequate surgical debridement
• Soft-tissue condition
• Infection and organism suitability for the planned strategy
• Patient factors

Do All Infected Implants Need to Be Removed?

No. Fixation is part of the fracture-healing strategy, so implant removal cannot be considered independently from fracture stability.

Retention may be considered in selected cases when fixation is stable, alignment is acceptable, fracture healing remains achievable, adequate surgical debridement is possible, soft tissues are manageable, the infection and organism are suitable for the planned strategy, and patient factors support it.

Removal or exchange becomes more relevant when fixation is unstable or failed, reduction is unacceptable, the fracture has healed and implants are no longer mechanically required, adequate debridement cannot otherwise be achieved, or the infection strategy requires exchange or removal.

Infection duration alone should not determine the decision.

What Is Surgical Debridement?

Adequate debridement is a central surgical principle.

It may include removal of:

• Purulent material
• Necrotic tissue
• Devitalized bone
• Foreign material or implants when indicated

Debridement does not always require removal of all fixation.

What If the Fracture Has Not Healed?

When infection is present before union, treatment must preserve or restore sufficient stability for the fracture to heal.

Possible strategies can include:

• Retention of stable fixation in selected early cases
• Exchange fixation
• External fixation
• Staged reconstruction
• Bone grafting after infection control
• Other individualized methods

The exact strategy depends on the fracture and infection.

What If There Is Bone Loss?

Infection can produce or worsen bone defects.

Reconstruction may require:

• Staged debridement
• Local antibiotic strategies
• Bone graft
• Bone transport
• Induced membrane techniques
• Other defect reconstruction

Large infected defects are among the more complex problems in orthopedic trauma.

What Role Do Antibiotics Play?

When surgery and microbiological sampling are planned, the timing of antibiotics is coordinated by the treating team so that urgent treatment is not delayed while also maximizing the usefulness of cultures when clinically appropriate.

Systemic antimicrobial treatment is individualized according to microbiology, surgical strategy, implant status, patient factors and infectious-disease or clinical assessment.

Patients should not stop or modify prescribed antibiotics without instructions from their treating team.

What Are Local Antibiotics?

Local antimicrobial carriers can be used in selected cases as an adjunct to an overall surgical and antimicrobial plan.

They do not replace:

• Adequate debridement
• Fracture stability
• Appropriate systemic treatment
• Soft-tissue management

Why Are Soft Tissues Important?

Infected fractures often occur in areas with damaged skin and muscle.

Durable soft-tissue coverage is an important component of infection control and fracture reconstruction.

Adequate coverage is essential for:

• Wound healing
• Bone healing
• Infection control
• Protection of implants

Plastic and reconstructive surgery may be required for selected defects.

Can Infection Cause Nonunion?

Yes.

Infection can interfere with both the biology and mechanical environment required for fracture healing.

This can result in infected nonunion, which requires simultaneous management of infection and fracture reconstruction.

When Is Staged Reconstruction Considered?

Staged reconstruction may be appropriate when:

• Repeated debridement is required
• Bone viability is uncertain
• A large bone defect exists
• Soft-tissue reconstruction is needed
• Temporary stabilization is required
• Definitive fixation cannot safely be performed initially

Some infections can be treated in one procedure; staging is not mandatory in every fracture-related infection.