Principles of fracture management, open fractures and

• A fracture is a break in the structural continuity of bone; the way it is described (bone, site, pattern, displacement, open or closed) determines the management.
• Bone heals by regeneration in three overlapping stages (inflammation, repair, remodelling), helped by healthy bone, good blood supply and mechanical stability.
• Reduction restores alignment; immobilisation protects it. Splints are used early while the limb swells; definitive fixation (nailing, plating, external fixation) follows when the patient and the limb allow.
• An open fracture communicates with the outside world through a wound. Infection risk rises steeply with soft-tissue damage (Gustilo grade), so antibiotics, irrigation and timely debridement are central, and soft tissue cover is usually achieved within 72 hours. ^[6][7]
• Acute compartment syndrome is a surgical emergency: pain out of proportion and pain on passive stretch, with tissue pressure threatening the limb. It is treated by immediate open fasciotomy, not by watching and waiting.

By the end of this page you should be able to:

1. Describe a fracture accurately, including site, pattern, displacement and its relationship to skin and joints.
2. Explain the stages of fracture healing and the factors that delay it.
3. Recognise the common complications of fractures and their mechanisms.
4. Apply the principles of reduction, splinting, traction and definitive fixation.
5. Classify an open fracture with the Gustilo-Anderson system and choose antibiotic prophylaxis, irrigation and debridement timing.
6. Recognise acute compartment syndrome, interpret compartment pressures, and outline fasciotomy.
7. Explain the BOAST, AO Foundation and NICE NG37 positions on open fractures and limb salvage.

Fractures are among the most common injuries a clinician meets, and they are rarely just a broken bone. The bone break is often the least of the problem: it is the damage to skin, muscle, blood vessels and nerves, and the risk of infection, that decides the outcome. This page therefore covers the whole chain from first describing the fracture, through how bone heals and what goes wrong, to the surgical and non-surgical management of the fracture itself, then of the two serious complications that run through the whole subject: the open fracture and acute compartment syndrome.

Fractures are classified in several useful ways.

By skin integrity:

• Closed (simple): the skin is intact; the fracture has no communication with the outside. This is the commoner pattern.
• Open (compound): the skin or mucosa over the fracture is breached, or a wound leads down to the fracture, so bone is exposed to bacteria. This carries a high infection risk and is a surgical emergency.

By completeness:

• Complete: the bone is broken into two or more separate fragments.
• Incomplete: the bone bends or cracks but retains some continuity (greenstick, buckle and plastic deformation in children).

By mechanism and pattern (described below): transverse, oblique, spiral, comminuted, segmental, impacted, avulsion.

By site relative to the growth plate (children): Salter-Harris types I to V.

Severity scores such as Mangled Extremity Severity Score (MESS), Nerve Injury-Ischaemia-Soft Tissue-Skeletal Injury-Shock-Age (NISSSA) and Limb Salvage Index have been devised to guide amputation decisions, but guidelines agree that the decision should not be based on a score alone ^{[3] [8]}.

Fractures are common in all ages: high-energy injuries in young adults (road traffic, falls from height, sport) and low-energy fragility fractures in older adults (especially osteoporotic hip and wrist fractures). A United Kingdom study put the incidence of open long-bone fractures at about 11.5 per 100,000 people per year, with the tibia the most commonly involved lower-limb bone ^[8]. Worldwide, open fractures carry a significant burden of disability and infection; reported infection rates range from 0 to 9 percent for Gustilo grade I, 2 to 10 percent for grade II, and 10 to 50 percent for grade III ^{[7] [8]}. ^[6]

Most fractures follow one of four mechanisms:

• Direct force: a blow or crush at the site.
• Indirect force: torsion (spiral fracture), bending (transverse/oblique), or axial load (impaction, compression).
• Repetitive loading: stress (fatigue) fracture in athletes or military recruits.
• Pathological loading: fracture through abnormal bone (tumour, infection, osteoporosis, Paget disease), often with minimal trauma.

Risk factors for poor outcome and non-union include high-energy injury, open fracture, bone loss, infection, smoking, diabetes mellitus, peripheral vascular disease, older age, malnutrition and vitamin D deficiency ^{[5] [6]}. Children's fractures differ because their bone and thick periosteum heal faster and tolerate more remodelling.

Precise description is the first management step, because the words determine the plan.

Anatomic location:

• Which bone, and which third or region (proximal, middle, distal; epiphysis, metaphysis, diaphysis).
• Whether the fracture is intra-articular (extends into the joint surface) or extra-articular. Articular extension is a step or gap at the joint surface and usually changes management.
• In children, involvement of the physis and the Salter-Harris type.

Pattern:

• Transverse: within about 30 degrees of a line perpendicular to the shaft axis.
• Oblique: more than about 30 degrees from that line, in a single plane.
• Spiral: a multiplanar fracture line from torsion.
• Comminuted: three or more fragments.
• Segmental: a separate intact segment between two fracture lines.
• Impacted or compression: fragments driven into each other.
• Avulsion: a small fragment pulled off by a tendon or ligament.

Soft tissue envelope:

• Closed: skin intact.
• Open: skin or mucosa breached and the fracture exposed. Grade with Gustilo-Anderson (below).
• Grading of closed soft-tissue damage (Tscherne) may also be used.

Displacement (distal fragment relative to proximal, in anatomic position):

• Translation: side-to-side shift, recorded in millimetres or as a percentage of bone width; 2 mm or less is generally called minimally displaced ^[5].
• Angulation: direction and degrees (named by the apex of the angle or by where the distal fragment points, for example varus or valgus).
• Shortening or distraction along the bone's long axis (overlap or a gap).
• Rotation: judged clinically and on films, often obvious in hand or forearm fractures.
• If all are normal, the fracture is undisplaced (non-displaced).

Associated injuries: neurovascular status (documented both limbs), compartment state, joint dislocation (for example Monteggia or Galeazzi), second fracture in paired bones, ligament injury. Imaging should include at least two orthogonal views and the joint above and below the fracture ^{[4] [5]}.

Bone heals by regeneration, not by scar. Three overlapping stages are described:

1. Inflammatory stage (hours to days). Vessels tear, a haematoma forms at the fracture and a brief inflammatory response recruits cells. The haematoma provides a fibrin scaffold. The inflammatory stage makes up roughly the first tenth of total healing time ^[5].
2. Repair (reparative) stage (from the end of the first week). Fibroblasts, chondrocytes and osteoblasts build a soft cartilaginous callus that bridges the gap and gives provisional stability; angiogenesis follows. Cartilage begins to ossify about three weeks after injury, forming the hard (bony) callus ^[5]. Immobilisation is essential during the early part so that new vessels and matrix are not repeatedly disrupted.
3. Remodelling (months to years). Woven bone of the callus is resorbed and replaced by lamellar bone; the external callus is shaped according to mechanical load (Wolff law). The medullary cavity is re-established.

Two modes are distinguished:

• Primary (direct) healing: needs absolute stability, usually after rigid compression plating. There is no callus; healing is by intramembranous ossification. Do not expect a callus on X-ray.
• Secondary (indirect) healing: occurs with relative stability (casting, external fixation, intramedullary nailing, locked plating). A callus should appear. This is the commoner mode ^[5].

A balance of motion and stability is required: too much motion gives fibrous tissue or non-union, too little (over-stabilisation) removes the stress stimulus and a fracture may remain woven bone.

Negative factors include a severe or high-energy injury, open fracture, bone loss, devitalised bone, contamination, infection, advanced age, malnutrition, smoking (smoking increases non-union risk), diabetes, peripheral vascular disease, vitamin D deficiency and possibly non-steroidal anti-inflammatory drugs in the early healing period ^[5]. An adequate blood supply through intact soft tissue is so important that periosteal stripping during fixation can devitalise bone and convert a simple fracture into a slow union.

Early and late complications:

• Neurovascular injury at the time of fracture (document and reassess).
• Malalignment, malrotation, shortening or angulation (malunion).
• Delayed union and non-union. The formal definition of non-union is a fracture older than nine months with no progressive healing for three consecutive months, although surgeons may make the diagnosis earlier if it is clear that healing will not proceed; the risk of non-union is roughly 5 percent overall but varies with site, displacement and patient factors ^[5].
• Infection: superficial wound infection and deep infection including osteomyelitis, more likely in open and high-energy fractures.
• Compartment syndrome (below).
• Avascular necrosis of bones with precarious blood supply (femoral head/neck, scaphoid, talus), from disrupted vessels.
• Venous thromboembolism, fat embolism syndrome.
• Growth disturbance and premature physeal closure in children.
• Complex regional pain syndrome, stiffness, weakness and loss of function.
• Hardware failure or refracture.
• Amputation when a limb is not salvageable.

Imaging:

• Plain radiographs (minimum two views) for diagnosis, alignment, articular involvement.
• CT for complex articular or pelvic fractures and pre-operative planning.
• MRI for occult fracture, marrow pathology or ligament injury.
• Angiography or CT angiography when vascular injury is suspected.
• Ultrasound for dynamic evaluation in skilled hands.

Laboratory testing is guided by trauma and comorbidity: full blood count, clotting, renal function, blood sugar, cross-match, and infection markers when late complications are feared.

Compartment pressure measurement is used when the diagnosis of acute compartment syndrome is uncertain (below).

• Open/closed and Gustilo-Anderson grade (Table) for open fractures.
• AO/OTA fracture classification for pattern (used alongside plain description).
• Salter-Harris for physeal injuries in children.
• AO classification for soft-tissue injury in closed fractures.
• Compartment pressure criteria (below) as a diagnostic aid, not a substitute for clinical judgement.

• Assess and resuscitate using trauma principles (airway, breathing, circulation) first; fractures and bleeding come after life threats.
• Suspected spinal injury: immobilise before movement.
• Check and document neurovascular status of the affected limb, before and after any manipulation.
• Analgesia: intravenous morphine is commonly used as first-line in major trauma in many systems; ketamine or regional techniques are alternatives depending on training and protocol.
• Realignment and splinting are the first local treatment. Realignment improves pain control, arterial inflow, venous drainage and soft-tissue tension, and reduces bleeding and nerve compression ^[5].
• Splints are non-circumferential and accommodate swelling; circumferential casts are applied later, with extra padding over bony prominences.
• Traction: cutaneous (temporary, for comfort) or skeletal (preferred for prolonged use or unstable fractures), maintaining length and alignment until definitive fixation.
• Dislocated joints need urgent reduction.
• Tetanus status and prophylaxis should be checked in any open wound.

• Closed reduction: manipulation without opening the fracture, usually under sedation or anaesthesia; used when fragments can be aligned without surgery.
• Open reduction: surgical exposure, direct visualisation; combined with internal fixation when needed.
• Traction and external fixation may be used as a temporary bridge (damage-control orthopaedics) in unstable, multiply-injured or under-resuscitated patients, with definitive fixation once physiology allows ^[5].

The choice depends on fracture pattern, site, soft-tissue state, patient factors and the surgeon's expertise.

• Non-operative: casting, functional splintage, or traction, with weight-bearing allowed as stability and pain permit.
• External fixation: pins connected by an external frame. Used as a temporary measure in unstable or open fractures, sometimes definitively. Least disruptive to soft tissues.
• Internal fixation:
  • Screws and plates (compression plating gives absolute stability and primary healing; bridge plating gives relative stability and secondary healing).
  • Intramedullary nailing: relative stability, good for long-bone shaft fractures, sparing soft tissues around the fracture.
  • Tension-band, locking plates and other constructs.
• The core AO principle running through all of this is preservation of blood supply and mechanical stability: enough stability for healing without devitalising the bone and soft tissue ^[4].
• Post-operatively: elevate the limb, mobilise and bear weight early where safe (to reduce osteopenia, sarcopenia and thrombosis), and reassess at regular intervals.

An open fracture is a fracture with a break in skin or mucosa that communicates with the fracture, exposing bone to bacteria. It is not simply a worse closed fracture: it changes the diagnosis, the antibiotic cover, the timing of surgery and the prognosis.

The most widely used system is the Gustilo-Anderson classification (originally for tibial open fractures; applied more widely) ^{[6] [8]}:

Gross contamination raises any fracture to grade III. The same classification is only moderately reliable between observers, so treatment should be based on the wound as found rather than on the label alone ^[6]. A newer alternative, the OTA Open Fracture Classification, stratifies skin, muscle, arterial, contamination and bone-loss domains and may predict complications better, but it is more complex and not yet widely used ^{[6] [8]}.

Infection risk rises steeply with grade. Original Gustilo data reported infection in 0 to 2 percent of type I, 2 to 2.4 percent of type II, 4 percent of IIIA, and up to 42 to 52 percent of IIIB and IIIC fractures; later and pooled data quote 0 to 9 percent for grade I, 1 to 12 percent for grade II, and 9 to 55 percent (often 10 to 50 percent) for grade III ^{[6] [7] [8]}. Patients with higher contamination levels carry higher infection rates (mild 5 percent, moderate 8 percent, severe 23 percent in the FLOW trial cohort) ^[6].

• Urgent trauma assessment and resuscitation first.
• Give prophylactic intravenous antibiotics as early as possible. BOAST recommends ideally within 1 hour of injury ^[1]; much of the literature and many protocols use a 3-hour outer limit, after which infection risk rises significantly ^{[7] [8]}.
• Handle the wound as little as possible: remove only gross contamination, take photographs (BOAST and NICE require information-governance policies that allow 24-hour photography, with photographs kept in the records) ^{[1] [3]}.
• Do not irrigate in the pre-hospital setting or in the emergency department before formal wound excision ^[3]. Cover the wound with a saline-soaked dressing and an occlusive film.
• Realign and splint the limb ^{[1] [3]}.
• Assess and document neurovascular status; repeat after any manipulation.
• Administer antibiotics immediately in the emergency department if not already given ^[3].
• Tetanus prophylaxis according to vaccination history.
• Transfer to a specialist centre able to provide orthoplastic (combined orthopaedic and plastic surgery) care if a long bone, hindfoot or midfoot is involved ^{[1] [3]}.

Conceptually, a first-generation cephalosporin (for example cefazolin) covers the gram-positive organisms (mainly Staphylococcus aureus) that cause most grade I and II infections; grade III fractures add gram-negative cover with an aminoglycoside such as gentamicin; farm or soil contamination adds penicillin for possible Clostridium ^[7]. In practice a United Kingdom orthoplastic regimen (BOA/BAPRAS) is intravenous co-amoxiclav 1.2 g or cefuroxime 1.5 g every 8 hours, with clindamycin 600 mg if the patient is allergic to penicillin ^[8]. Other systems use cefazolin-based regimens.

Duration:

• Grade I and II: 24 hours after wound closure ^{[7] [8]}.
• Grade III: 48 to 72 hours after injury, but no more than 24 hours after wound closure/definitive coverage ^{[7] [8]}.
• Many guidelines stop antibiotics within 24 hours of achieving soft-tissue cover or within 72 hours of injury ^{[2] [6]}.

Antibiotic choice should follow local trust guidelines, allergy status and the wound's environment. Extended-spectrum or gram-negative cover is not clearly beneficial beyond grade III by current evidence, and aminoglycosides carry nephrotoxicity (some polytrauma protocols prefer ceftriaxone or fluoroquinolones to avoid kidney injury) ^{[5] [6]}.

Formal debridement is cleaning and removal of contaminated, devitalised and necrotic tissue, layer by layer, in theatre.

Timing from BOAST and NICE NG37 ^{[1] [3] [8]}:

• Immediately (within hours): highly contaminated wounds (agricultural, aquatic, sewage), associated vascular compromise, compartment syndrome, or multiple injuries.
• Within 12 hours: high-energy open fractures, likely Gustilo grade IIIA or IIIB, that are not highly contaminated.
• Within 24 hours: all other (low-energy) open fractures.

In theatre: preferably general anaesthesia if compartment syndrome is possible (regional block can mask it); systemic antibiotics continued; wound re-prepped and draped as clean surgery after debridement; second-look debridement at 24 to 48 hours if needed. Irrigation is low-pressure warm saline; adding soap or antibiotics to lavage does not improve outcome, and antiseptics/surfactants are inferior to saline alone ^{[6] [8]}. Commonly cited irrigation volumes are 3, 6 and 9 litres for grades I, II and III, although the ideal volume is not defined ^[6].

• The fixation and coverage plan is made jointly by consultant orthopaedic and plastic surgeons (combined orthoplastic approach) ^{[1] [3]}.
• Definitive internal stabilisation is only performed when it can be followed immediately by definitive soft-tissue cover; otherwise infection risk rises ^{[1] [8]}.
• Definitive soft-tissue closure or coverage: at the same sitting if the list allows within the debridement window, or within 72 hours of injury if not ^{[1] [3] [8]}.
• Definitive fixation (nails, plates or external fixation) is chosen by fracture pattern, site, soft-tissue injury, patient factors and surgeon experience; external fixation is preferred when soft tissues are badly damaged, often as a bridge before later internal fixation ^[8].
• Negative-pressure wound therapy is not a substitute for cover, although it is useful as a temporary dressing; it does reduce infection when applied to a closed incision ^[6].

The decision is made by a multidisciplinary team (orthopaedic surgeon, plastic surgeon, rehabilitation specialist, patient and family), not by a score alone ^[3]. Emergency amputation is performed for uncontrolled life-threatening bleeding, unacceptable risk to life, or a limb judged unsalvageable after orthoplastic assessment. Where indicated, delayed primary amputation is performed within 72 hours of injury ^[3].

Acute compartment syndrome is elevated pressure within a muscle compartment (enclosed by fascia and bone) that reduces perfusion and, if untreated, causes muscle necrosis and nerve injury ^{[2] [5]}. It can occur with or without a fracture, after crush injury, ischaemia-reperfusion, burns, tight dressings or casts, and after prolonged positioning.

The compartment pressure rises; venous and then arterial flow fall; tissue ischaemia develops. The amount and duration of pressure correlate with the amount of irreversible tissue loss, so early recognition and decompression are essential ^[5]. Untreated, this can lead to rhabdomyolysis, renal failure, sepsis and loss of the limb.

Diagnosis is clinical. Classic features (the "five Ps") are pain (out of proportion and worsened by passive stretch), pallor, paraesthesia, paralysis and pulselessness, but the last four are late or unreliable signs. The key features in a conscious patient are:

• pain out of proportion to the injury
• pain on passive movement of the muscles of the involved compartments
• a tense, swollen compartment
• altered sensation (early)
• motor weakness (later)
• pulselessness (very late)

In obtunded, sedated, multiply injured or regionally anaesthetised patients the diagnosis can be silent, so a low threshold for screening is needed; aggressive screening has found around a fifth of severely injured patients affected ^[5].

BOAST requires hourly assessment of at-risk patients, recording of findings whether present or not, interpretation and rationale; baseline and subsequent documentation of time of examination, mechanism, consciousness, neurovascular status, pain and analgesic dose ^[2]. Analgesic and regional anaesthesia use should be agreed between patient, anaesthetist and surgeon, with an agreed policy for monitoring ^[2].

When clinical assessment is inconclusive or impossible (uncertain signs, unconscious or regionally blocked patient), intracompartmental pressure measurement is indicated. The limb is elevated to heart level and circumferential dressings are released to skin; blood pressure is maintained; the patient is re-evaluated within 30 minutes ^[2].

Pressure guides ^{[2] [5]}:

• A difference between diastolic blood pressure and compartment pressure of less than 30 mmHg indicates increased risk of compartment syndrome.
• An absolute compartment pressure above 40 mmHg (with clinical features) supports urgent surgical decompression.
• The decision to operate or continue monitoring is made by a consultant orthopaedic surgeon.

Pressure monitoring has a significant device failure rate, and many orthopaedic surgeons advise that high clinical suspicion should lead to fasciotomy even if pressures are low ^[5].

Fasciotomy is the only definitive treatment.

• Immediate surgical decompression once the diagnosis is made ^[2].
• Open decompression of all involved compartments, with debridement of non-viable muscle; viability of each structure in each compartment is documented in the operation record.
• In the lower leg, a two-incision, four-compartment decompression is recommended (medial and lateral), following the same lines advised for open-fracture debridement ^{[1] [2]}.
• Discuss every patient with a plastic surgeon within 24 hours of fasciotomy and re-explore within 72 hours (or earlier if indicated), with a documented plan for soft-tissue management ^[2].
• For foot compartment syndrome there is no consensus; the management plan must be justified and documented ^[2].
• Delayed presentation (over about 12 hours) carries a high risk of surgical complications; decision-making should involve two consultants and non-operative management (with renal protection) is an option ^[2].
• Different axes and techniques apply to the thigh, arm, forearm and hand, taking reconstructive options into account.

• Split, do not circumferentially cast, in the acute phase.
• Maintain a high index of suspicion after high-energy injury, arterial injury, significant swelling, tight casts, burns and in obtunded patients.
• Compartment syndrome is part of the routine documented evaluation of patients with limb injuries or after extremity surgery ^[2].
• Watch for compartment syndrome for at least 48 hours after tibial fracture or fixation, with advice to patients about self-monitoring on discharge ^[3].

• Children: bone heals fast; incomplete fractures (greenstick, buckle) are common; growth-plate injuries need careful classification; children tolerate and remodel more deformity but serious vascular or compartment injuries are still emergencies.
• Older adults: fractures are often fragility fractures through osteoporotic bone; comorbidity and skin quality matter; rehabilitation goals should be set early.
• Pregnancy: trauma in pregnancy is managed by a combined obstetric and surgical team; vascular assessment and radiation exposure are balanced against maternal need.
• Patients on anticoagulants or with bleeding disorders need a coordinated plan; trauma triggers specific protocols.

• Splints, dressings and careful serial documentation cost little and save limbs; a well-applied non-circumferential splint and a saline-soaked dressing with an occlusive film are the starting point.
• Antibiotics should be given within the same time windows; cefazolin and, where appropriate, gentamicin are widely available.
• Debridement timing should follow the same windows (immediate for high contamination, within 12 hours for high-energy, within 24 hours for others) even if transfer is needed first. ^[1][3]
• Compartment monitoring can be done with a simple needle, manometer and blood-pressure cuff when a dedicated device is not available; if there is doubt and the limb is at risk, urgent fasciotomy is safer than waiting.
• Early transfer to a centre with orthoplastic capability should be arranged; where transfer is not possible, the principles (radical debridement, stabilisation, early cover) still apply.
• Rehabilitation, wound care and infection control after surgery are as important as the operation.

• Describe a fracture clearly first (bone, site, pattern, displacement, skin, joints) and image with two views including the joints above and below.
• Reduction restores alignment; splints and traction bridge the gap; definitive fixation (nailing, plating, external fixation) is chosen by pattern, soft tissues and patient state.
• Bone heals by inflammation, repair and remodelling over months to years; immobilisation protects early repair, and blood supply determines success.
• Malunion, delayed or non-union, infection and avascular necrosis are the principal complications; smoking, diabetes and poor blood supply worsen outlook.
• An open fracture is a surgical emergency: antibiotics within 1 hour if possible, no irrigation before debridement, saline dressing and splint, debridement in theatre within 12 or 24 hours according to energy and contamination, and definitive soft-tissue cover within 72 hours. ^[1]
• Gustilo grade estimates infection risk rising from 0 to 2 percent in grade I to 10 to 50 percent in grade III; antibiotic choice and duration follow the grade.
• Acute compartment syndrome is diagnosed clinically (pain out of proportion, pain on passive stretch) with pressure support: a diastolic-to-compartment difference under 30 mmHg or an absolute pressure over 40 mmHg indicates danger.
• Fasciotomy is the treatment; do not delay waiting for all the classic signs.
• Guidelines differ between countries; the newest iterations (BOASts updated 2025, NICE NG37 last updated 2022) retain the same time windows and thresholds.
• Decisions on limb salvage, amputation and coverage are shared, multidisciplinary and made with the patient.

Fracture classification and AO/OTA system; fixation and internal fixation principles; osteomyelitis and fracture-related infection; shock and trauma resuscitation; hand fractures; paediatric fractures and growth-plate injuries; regional anaesthesia; venous thromboembolism; tetanus and immunisation; wounds and soft-tissue reconstruction; trauma imaging.

(Planned MedGrasp cross-links, to be added when those topics are verified: musculoskeletal trauma and polytrauma assessment, major trauma service delivery, paediatric orthopaedic injuries.)