Open fractures and early antibiotic prophylaxis

01OverviewDefinition, clinical context and the essential points that orientate the chapter.

An open fracture is present when a wound communicates with the fracture or fracture haematoma. The wound may be remote from the break or only a pinhole produced from inside by a sharp fragment. Treat uncertainty as open until specialist assessment. The first priorities remain CABCDE and haemorrhage control. Then expose the whole limb, inspect without probing, document contamination and tissue loss, and perform a precise vascular and named-nerve examination before manipulation.

Antibiotic prophylaxis is time-critical. NICE and BOASt require intravenous prophylaxis immediately, ideally within one hour. The exact agent and redosing schedule should come from the agreed trauma-network protocol because local resistance, allergy pathways and contamination exposures differ. Prescribe a real agent, dose and administration time from that protocol rather than writing a generic intention. Farm, aquatic, sewage, bite or established infection exposure needs early microbiology advice and broader treatment where specified.

Wound handling before theatre is deliberately limited. Remove only gross loose material that can be lifted without exploration, photograph the wound, apply saline-soaked sterile gauze and seal with an occlusive film. Do not irrigate, probe, take superficial swabs or close the wound in the emergency department. These actions neither replace debridement nor reliably define bacterial burden, and repeated dressing changes expose tissue and lose information.

Restore alignment and protect perfusion. Give analgesia, gently correct gross deformity when required, splint across appropriate joints and repeat pulse, refill, temperature and individual motor and sensory findings. A pulseless or ischaemic limb, expanding haematoma, active haemorrhage or bruit requires immediate vascular and orthopaedic coordination. NICE advises CT angiography for suspected extremity vascular injury in stable patients, but hard signs and threatened perfusion should not be delayed by avoidable imaging.

Formal debridement is performed by appropriately experienced orthopaedic and plastic surgeons. Extend the wound safely, remove foreign material and non-viable tissue, irrigate, reassess muscle and bone viability and plan stability and cover. BOASt timing depends on urgency: immediate for gross contamination, sewage or vascular compromise; within twelve hours for other high-energy injury; and within twenty-four hours for lower-energy wounds. Repeated low-quality washouts are not a substitute for one planned definitive excision.

Fixation and soft-tissue cover are interdependent. Stable bone supports tissue healing, while vascularised cover protects bone and implants. The orthoplastic team should agree definitive fixation, antibiotic delivery, vascular repair, nerve or tendon management and flap or graft strategy from the start. If cover cannot be completed at initial debridement, BOASt expects definitive closure or cover within seventy-two hours. Internal fixation should align with immediate definitive cover rather than leaving exposed metal.

After surgery, monitor tissue viability, compartment symptoms, perfusion, infection, renal function where nephrotoxic antibiotics are used, fixation and rehabilitation. Antimicrobial duration follows the network protocol and operative findings; prolonged prophylaxis without indication creates toxicity and resistance. Address smoking, diabetes, nutrition and vascular disease. Explain warning signs, weight-bearing restrictions, wound plan and named follow-up because infection and nonunion may become apparent after discharge.

Key points

Any wound in the same limb segment as a fracture can communicate; document size, site, contamination and photographs before covering, without probing it in the emergency department.
Assess pulses, capillary refill and individual motor and sensory nerve function before and after alignment or splintage; hard vascular signs trigger immediate surgical escalation.
Give intravenous prophylaxis from the agreed open-fracture network protocol immediately, ideally within 1 hour of injury; record agent, dose and time and modify unusual contamination with microbiology advice.
Remove only gross loose surface contamination, photograph, cover with saline-soaked sterile gauze and an occlusive layer, then leave the dressing undisturbed until formal debridement unless clinically necessary.
Do not perform emergency-department mini-washouts, wound probing or primary closure; these contaminate tissue planes and compromise later assessment.
Realign gross deformity, splint and repeat neurovascular status; tetanus prevention follows UK immunisation guidance and does not replace antibiotic prophylaxis.
BOASt timing: immediate debridement for highly contaminated wounds or vascular compromise, within 12 hours for other high-energy fractures, and within 24 hours for lower-energy open fractures.
Plan debridement, skeletal stabilisation and definitive soft-tissue cover jointly through orthopaedic and plastic surgery; achieve cover at debridement or within 72 hours when not immediately possible.

02AetiologyUnderlying causes, associations and risk factors, with why each one matters.

High-energy direct trauma

Road collision, crush and industrial mechanisms disrupt bone and its soft-tissue envelope, creating contamination, devascularisation and complex segmental injury.

Low-energy skin breach

A displaced fragment can pierce skin from within and create a small communicating wound with less visible contamination but genuine infection risk.

Special contamination

Farmyard, standing water, sewage, bite and marine exposure introduces organisms not covered by every standard protocol and needs microbiology-informed modification.

03PathophysiologyThe causal sequence from the underlying abnormality to symptoms and harm.

1
Loss of biological barrier
Communication between fracture and environment inoculates deep tissue and bone, while damaged vessels and dead space reduce immune and antimicrobial delivery.
2
Soft-tissue devitalisation
Crush and shear create a zone of injury larger than the visible wound; marginal muscle and skin may declare non-viability over time.
3
Fracture instability
Movement disrupts clot, worsens pain and damages vessels, nerves and soft tissue, whereas careful realignment and splintage protect the remaining envelope.
4
Infection and nonunion
Bacterial burden, necrotic tissue, inadequate stability and poor vascularity interact to cause deep infection, delayed union and chronic osteomyelitis.

04Clinical features and red flagsSymptoms, examination findings, patterns of presentation and time-critical warnings.

Communication suspected

A wound, puncture or degloving in the injured segment is considered open until adequately assessed, even when bone is not visible.

Vascular emergency

Active haemorrhage, expanding haematoma, bruit, absent distal signals, pallor, coolness or deteriorating neurological function requires immediate revascularisation planning.

Heavy contamination

Soil, faeces, stagnant water, farmyard material or embedded debris raises infection risk and changes urgency and antimicrobial discussion.

Compartment syndrome

Escalating pain, analgesic requirement, passive-stretch pain, tense compartments and evolving nerve signs demand immediate senior assessment despite an open wound.

Degloving and threatened skin

Reduced sensation, abnormal mobility, bruising, blistering or non-blanching skin may represent devascularised tissue beyond the visible wound.

Systemic vulnerability

Diabetes, smoking, peripheral vascular disease, immune suppression, malnutrition and frailty increase infection, wound failure and nonunion risk and shape optimisation.

Red flags requiring action

Absent or deteriorating perfusion, hard vascular signs, uncontrolled bleeding or an ischaemic limb requires immediate combined orthopaedic and vascular intervention without delaying revascularisation for grading.
Gross agricultural, aquatic, sewage or heavily particulate contamination, compartment syndrome or a multiply injured unstable patient changes antimicrobial, debridement and damage-control priorities.
A pinhole wound near a fracture, degloving, skin under tension or exposed bone or tendon must be assumed to communicate until explored appropriately in theatre.

05InvestigationsWhat to request, why it matters and how to interpret it.

Investigation order

Read from the initial assessment onwards. Tests may run in parallel in urgent care; first-line, preferred, confirmatory, definitive and gold-standard labels appear only when the chapter explicitly states them.

01
First-line orthogonal radiographsFirst stepFirst line
Why
Define fracture, foreign material and joint involvement.
Interpretation and limitations
Image the entire injured bone with adjacent joints where appropriate, but never delay antibiotic delivery, splintage or vascular action to perfect a view.
02
CT for complex anatomy
Why
Map articular, pelvic or segmental fracture and operative architecture.
Interpretation and limitations
Use after immediate limb and life threats are controlled; CT defines bone but underestimates dynamic tissue viability and does not replace surgical exploration.
03
Preferred CT angiography when stablePreferred
Why
Assess suspected arterial injury without hard signs requiring immediate operation.
Interpretation and limitations
Occlusion, extravasation, intimal injury or poor distal run-off directs combined vascular and orthopaedic planning; threatened ischaemia must not wait unnecessarily.
04
Baseline blood tests
Why
Prepare for surgery and identify bleeding, renal and metabolic risk.
Interpretation and limitations
Obtain FBC, group and screen or crossmatch, renal profile, glucose and coagulation where indicated; results should not postpone immediate prophylaxis.
05
Operative deep samples
Why
Investigate established or suspected infection rather than simple contamination.
Interpretation and limitations
Multiple deep tissue specimens collected at debridement are more informative than superficial emergency swabs; coordinate timing with microbiology when infection is already present.
06
Photographic documentation
Why
Preserve wound information while minimising repeated exposure.
Interpretation and limitations
Take consent- and governance-compliant images at first assessment, label location and time, then seal the dressing until theatre unless clinical deterioration demands review.

06Differential diagnosisRealistic alternatives and the features that help distinguish them.

Closed fracture with abrasion

A superficial graze may not communicate, but proximity, depth and mechanism are unreliable at bedside; uncertain wounds are managed as open pending specialist assessment.

Traumatic arthrotomy

A wound over a joint can inoculate the capsule without a visible fracture and requires urgent joint-specific surgical assessment and antimicrobial prophylaxis.

Pure soft-tissue degloving

Extensive separation can threaten skin and perforators despite intact bone, needing plastics input, debridement and sometimes staged cover.

Pathological fracture with ulceration

Tumour, infection or neuropathic bone can fracture beneath chronic skin damage and requires diagnostic tissue and antimicrobial planning beyond routine trauma care.

07ManagementImmediate care, first-line treatment, alternatives and escalation.

01First hourProtect life, limb and woundFirst stepA fracture-associated wound is present or cannot confidently be shown not to communicate.

1Perform CABCDE, control haemorrhage and record pulse, refill, temperature and named motor and sensory nerve findings before any realignment.
2Administer the network-approved intravenous prophylactic agent immediately and ideally within one hour, recording the exact dose and time.
3Photograph without probing, remove only loose gross contamination, apply saline-soaked sterile gauze with an occlusive cover and splint the realigned limb.
4Contact the receiving orthoplastic service early and add vascular, microbiology or other specialty support for hard signs or unusual contamination.

02DebridementExcise and stabilise on timeThe patient has reached an appropriate surgical centre and physiology permits operative care.

1Operate immediately for vascular compromise or gross sewage, aquatic or agricultural contamination, within twelve hours for other high-energy injury and within twenty-four hours for lower-energy wounds.
2Perform systematic wound extension, removal of foreign material, excision of non-viable tissue and copious controlled irrigation by an experienced orthoplastic team.
3Restore vascularity and skeletal stability in a coordinated sequence, with fasciotomy when compartment syndrome or prolonged ischaemia requires it.
4DefinitiveAgree definitive cover at the first operation or a documented route to closure or flap cover within seventy-two hours.

03RecoveryPrevent infection and loss of functionDebridement, fixation and cover have been completed or staged.

1Continue antimicrobials only for the protocol-defined indication and duration, adjusting for cultures, allergy, renal function and confirmed infection rather than contamination alone.
2EscalationMonitor flap or wound viability, distal perfusion, compartment symptoms, inflammatory trajectory and fixation, escalating new drainage or necrosis promptly.
3Set explicit weight-bearing, splint, wound and handover instructions and begin therapy that protects reconstruction without unnecessary stiffness.
4Optimise smoking cessation, glycaemia, nutrition and vascular disease and arrange orthoplastic follow-up for union, infection and function.

Key medicines and prescribing safety2 treatments · regimens, roles and cautions

Provides early bacterial prophylaxis before formal debridement, with a consistent allergy and transfer plan across the trauma network.

Network open-fracture intravenous prophylaxis

Give the exact intravenous agent and adult dose specified by the receiving trauma network immediately and ideally within 1 hour of injury; redose and stop at the protocol-defined operative or post-cover point.

National guidance specifies timing rather than one universal drug; check severe allergy, renal function and unusual farm, water, sewage or bite contamination with microbiology and do not prolong prophylaxis as empirical infection treatment.

Prevents tetanus after contaminated injury and updates incomplete primary immunisation or boosters according to UK recommendations.

Tetanus-containing vaccine and human tetanus immunoglobulin

When UKHSA wound guidance indicates active immunisation, give 0.5 mL of the appropriate tetanus-containing vaccine intramuscularly; when immunoglobulin is indicated for prevention, give 250 IU intramuscularly, increased to 500 IU if more than 24 hours have elapsed or heavy contamination is present.

Tetanus measures do not replace open-fracture antibiotics or debridement; use a separate site for immunoglobulin and vaccine, verify immunisation and immune status, and seek specialist advice for treatment of suspected clinical tetanus.

08ComplicationsImportant consequences, why they occur and why they matter clinically.

Deep fracture-related infection

Persistent drainage, increasing pain, erythema, fever or later sinus formation can reflect infected bone and implants requiring multidisciplinary surgical and antimicrobial treatment.

Delayed union or nonunion

Bone loss, instability, vascular injury, infection and smoking impair healing and may require revision fixation, grafting or reconstruction.

Compartment syndrome

Swelling and reperfusion raise compartment pressure; worsening pain, passive-stretch pain and neurological change require urgent fasciotomy assessment.

Amputation and functional loss

Irreversible ischaemia, uncontrolled infection or unsalvageable composite tissue loss may require amputation, followed by early rehabilitation and psychological support.

09Monitoring and follow-upTreatment response, safety checks and longer-term review.

Repeat pulses, capillary refill, limb temperature and named motor and sensory examination after alignment, splintage, transfer and every operative stage.
Record antibiotic agent, dose, route and administration time, including redosing, allergy substitution and transfer responsibility.
Inspect dressings for strike-through and the patient for compartment syndrome without repeatedly opening the sealed wound cover.
After reconstruction, monitor flap or skin viability, renal function where relevant, temperature, pain trajectory and deep infection signs.
Follow radiographic union, fixation, weight-bearing progression and patient function, with rapid re-entry for drainage, wound breakdown or increasing pain.

10Special situationsVariants, exceptions and circumstances that change the usual approach.

Small wound, deep problem

A pinhole made by a fragment can communicate directly with bone and must not be dismissed by surface appearance.

Time belongs to antibiotics

Prompt intravenous prophylaxis can begin before detailed classification, imaging or transfer and should never await theatre.

Classification follows debridement

Soft-tissue viability and contamination are defined more accurately during formal exploration than through an emergency-department wound.

Stability supports biology

Effective fixation and vascularised cover work together; treating bone and soft tissue as separate sequential problems compromises both.

The photograph reduces exposure

Good initial documentation allows later teams to assess the wound while preserving the sealed sterile environment.

11Common pitfallsFrequent interpretation and management errors.

01
Waiting for radiographs or transfer acceptance before giving intravenous prophylaxis.
02
Probing, irrigating or closing the wound in the emergency department.
03
Calling a fracture closed because bone is not visible through a small nearby wound.
04
Failing to document individual nerve and perfusion findings before and after splintage.
05
Using a generic antibiotic phrase without prescribing the network agent, dose and time.
06
Planning fixation without an agreed definitive soft-tissue cover strategy.