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OverviewAetiologyPathophysiologyClinical features and red flagsInvestigationsDifferential diagnosisManagementComplicationsMonitoring and follow-upSpecial situationsCommon pitfallsQuestionsSources
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Educational draft · awaiting clinical reviewThe full textbook explains uncertainty but does not replace live national or local guidance, specialist advice, or current prescribing information.

Forearm fractures and Monteggia or Galeazzi patterns

Musculoskeletal medicine and orthopaedics · UK scope · Sources checked 27 Aug 2026 · Clinical review pending

RapidFull
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Open, compartment or vascular forearm

Sparse soft-tissue reserve and paired-bone instability make open wounds, arterial injury and acute compartment syndrome immediate threats; a missed radial-head or distal-radioulnar dislocation leaves major disability.

Action: Perform ABCDE after high energy, remove rings, cover open wounds and give antibiotics within one hour, document radial and ulnar pulses and named nerves, align and splint, examine elbow and wrist, and escalate tissue or perfusion threats immediately.

Overview

Treat the radius and ulna as a linked functional ring, recognise Monteggia and Galeazzi fracture-dislocations, document nerve and vessel status, and restore length, rotation and joint congruence.

The forearm is not two independent sticks. Its bones and radioulnar joints create a rotating unit. Record mechanism, hand dominance, wounds and pain at both ends. Palpate radial head during gentle rotation only when safe and assess distal radioulnar tenderness and stability. In children, ulnar plastic deformation may be the only clue to a Monteggia lesion; the radial-head relationship must be checked on every view.

Adults need accurate restoration of length, radial bow and rotation, usually with plate fixation for unstable shaft and fracture-dislocation patterns. An apparently isolated stable ulnar fracture can use functional treatment with close review, but widening displacement or associated joint injury changes the plan. Children may remodel angulation, not persistent joint dislocation or major rotation. Rehabilitation starts finger movement early and progresses elbow, wrist and forearm rotation according to stability.

Practice

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Musculoskeletal medicine and orthopaedicsOriginal SBA

Monteggia recognition

A child has an ulnar shaft fracture after a fall. Which additional radiographic relationship must be checked to avoid missing a Monteggia injury?

Choose one answer, then submit
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Sources and review status4 sources · checked 27 Aug 2026 · clinical review pending+
Sources

Sources and review status

National guidance is shown before implementation-dependent detail. Typical adult dose examples remain subject to patient factors, contraindications and the live BNF or specialist protocol. Source check completed 27 Aug 2026; clinical approval remains outstanding.

  • AO Surgery Reference adult forearm-shaft fractures
  • AO Surgery Reference paediatric forearm-shaft fractures
  • BOAST open fractures
  • BOAST diagnosis and management of compartment syndrome

Editorial contact: Doctor’s Passport editorial team. Source-check date is separate from clinical approval. Report a content problem · Content changes

Authoring stateComplete draftClinical stateAwaiting reviewJurisdictionUnited Kingdom
Adult both-bone fractures are usually unstable because muscle forces rotate and shorten each segment. Compression plating or another pattern-specific fixation restores the radial bow and ulnar length while preserving biology. The surgeon confirms proximal and distal radioulnar congruence after fixation and documents rotation. Monteggia treatment begins with anatomical ulnar restoration, which often reduces the radial head; persistent dislocation suggests malreduction or interposed tissue. In Galeazzi injury, radial fixation is followed by distal-joint stability testing and temporary stabilisation when unstable.

Children can often be treated with closed reduction and a well-moulded cast, but age, fracture level, rotation and remodelling potential matter. Plastic deformation deserves correction when it maintains radial-head dislocation. Check radiocapitellar alignment on every follow-up view and do not accept a joint that remains out because the ulnar line looks modest. Cast wedging or re-manipulation may address early loss of alignment, whereas delayed missed Monteggia injury becomes progressively harder to reconstruct. Parents need finger-perfusion and cast-pressure warning signs.

Compartment assessment continues after fixation because pain, swelling and tight dressings can evolve. Release external constriction completely to skin and reassess promptly when concern appears; pulses do not exclude pressure-related muscle ischaemia. Open injuries require the long-bone antibiotic and orthoplastic sequence, with wound excision and cover coordinated with fixation. A penetrating wound may injure median, ulnar or radial structures even if the bones look stable, so operative plans must follow the mapped examination rather than radiographs alone.

Therapy preserves tendon glide, forearm rotation and adjacent-joint movement. Encourage elevation and finger motion immediately, then progress elbow and wrist activity within fixation limits. Measure pronation and supination with the elbow positioned consistently. Persistent restriction may arise from malrotation, radioulnar synostosis, distal-joint incongruity or pain rather than simple weakness. A late patient with healed fracture but dislocated radial head needs specialist reconstruction assessment; repeated forceful manipulation risks nerve and cartilage injury.

Imaging review should be structured. On each AP and lateral, follow both cortices, compare radial bow, inspect proximal and distal radioulnar spacing and ensure the radiocapitellar line intersects the capitellum. A true lateral is essential before declaring radial-head location. In a Galeazzi pattern, ulnar styloid fracture, widened distal joint or altered ulnar variance supports instability but examination after radial reduction remains decisive. CT may clarify complex joint fragments, while MRI is rarely needed during initial shaft management unless a specific soft-tissue question persists.

Discharge documentation states cast or wound care, elevation, permitted finger and joint motion, lifting restriction and an emergency route for worsening pain, numbness, colour or swelling. Adults with plates need counselling about infection, hardware irritation and refracture risk after later removal. Children require early radiographic review because redisplacement can occur before symptoms change. Once union is established, return to manual work and sport progresses with rotation, grip and load tolerance rather than radiographic date alone.

Key points

  • Examine and image the whole forearm including elbow and wrist; a paired-bone ring injury is missed when images stop at the fracture.
  • Trace the radiocapitellar line on every elbow view: it should pass through the capitellum, and loss of alignment suggests radial-head dislocation.
  • Monteggia is an ulnar fracture or plastic deformity with radial-head dislocation; Galeazzi is a radial-shaft fracture with distal radioulnar-joint disruption.
  • Document radial and ulnar pulses and median, anterior interosseous, radial, posterior interosseous and ulnar functions before and after splintage.
  • Suspect compartment syndrome from worsening pain and passive-stretch pain even when pulses remain present.
  • For open long-bone injury, give intravenous prophylaxis within one hour, cover the wound and avoid bedside washout.
  • Most adult both-bone, Monteggia and Galeazzi injuries require anatomical fixation to restore length, radial bow, rotation and joint congruence.
  • Children have greater remodelling and may be treated by closed reduction and casting, but radial-head and distal-joint alignment must remain acceptable.
  • After fixation or casting, define forearm rotation, elbow and wrist movement and weight-bearing restrictions and monitor compartment and nerve findings.

Aetiology

01

Direct blow

A defensive or impact injury bends one or both forearm bones and may cause an isolated ulnar nightstick fracture or open damage.

02

Fall with rotation

Axial load through an outstretched hand plus pronation or supination produces paired-bone fractures or fracture-dislocation patterns.

03

High-energy crush

Machinery or collision creates severe comminution, soft-tissue loss, rising compartment pressure and neurovascular injury requiring integrated orthoplastic care.

Pathophysiology

  1. 1
    Forearm ring disruption

    Radius, ulna, interosseous membrane and proximal and distal radioulnar joints form a ring; disruption at one site demands a search for a second.

  2. 2
    Monteggia mechanism

    Ulnar fracture or bowing alters proximal forearm geometry and dislocates the radial head from the capitellum.

  3. 3
    Galeazzi mechanism

    Radial-shaft fracture shortens or rotates the radius and disrupts the distal radioulnar joint, causing painful unstable forearm rotation.

  4. 4
    Rotation loss

    Malreduction of radial bow, length or rotational alignment impairs pronation and supination even when both bones unite.

Clinical features and red flags

Both-bone fractureRed flag

Painful deformity, shortening and loss of pronation or supination follow substantial forearm trauma.

Monteggia patternRed flag

Ulnar fracture or bowing with radial-head dislocation causes elbow pain and abnormal radiocapitellar alignment.

Galeazzi patternRed flag

Radial-shaft fracture with ulnar-head prominence, wrist pain and distal radioulnar instability defines this pattern.

Compartment threatRed flag

Disproportionate increasing pain, passive finger stretch pain and progressive neurological change requires emergency action.

Posterior interosseous deficitRed flag

Finger and thumb extension weakness with preserved cutaneous sensation can accompany proximal radial-head displacement.

Red flags requiring action

  • Escalating pain, tense compartments, passive finger stretch pain or progressive weakness and paraesthesia requires immediate compartment assessment and decompression when diagnosed.
  • A wound, exposed bone, cool hand, pulse change or expanding swelling triggers urgent open-fracture and orthovascular management.
  • An ulnar fracture with radial-head malalignment or radial fracture with painful unstable distal radioulnar joint is not an isolated shaft fracture.

Investigations

  1. 01
    AP and lateral full-forearm radiographsFirst step
    Why
    Show both bones and include elbow and wrist for linked joint injury.
    Interpretation and limitations
    Trace radiocapitellar alignment and compare distal radioulnar congruence; cropped films are inadequate.
  2. 02
    Dedicated elbow and wrist views
    Why
    Define subtle radial-head or distal radioulnar dislocation and associated articular fracture.
    Interpretation and limitations
    Obtain when standard full-length views are not true or clinical concern persists.
  3. 03
    Serial compartment and neurovascular examination
    Why
    Detect pressure, nerve or arterial deterioration after reduction and casting.
    Interpretation and limitations
    Document pain trend, passive stretch, named functions, pulses and refill rather than a global label.
  4. 04
    CT for complex articular relationship
    Why
    Clarify radial head, sigmoid notch or distal radioulnar anatomy when operative planning requires it.
    Interpretation and limitations
    CT supplements but must not delay reduction of tissue, compartment or vascular threat.

Differential diagnosis

01

Isolated radial-head injury

Lateral elbow pain and rotation block can be a radial-head fracture, but full forearm imaging excludes Monteggia and longitudinal instability.

02

Distal radius fracture

Wrist-centred deformity may coexist with shaft or distal radioulnar injury and requires imaging of the complete forearm ring.

03

Elbow dislocation

Gross elbow deformity without shaft fracture may be isolated, although post-reduction films must exclude associated coronoid or radial-head injury.

04

Soft-tissue compartment injury

Severe swelling and pain after crush can cause compartment syndrome with or without an obvious displaced fracture.

Management

01Initial assessmentExamine the complete ringFirst stepA forearm fracture or deformity follows trauma.+
  1. 1Expose from shoulder to fingers, remove rings and inspect wounds and compartments.
  2. 2Record named nerves and pulses and provide analgesia, alignment and a padded splint.
  3. 3Obtain full-length images and identify radial-head and distal-radioulnar alignment explicitly.
02Adult unstable patternRestore both shaft and joint geometryBoth bones, Monteggia, Galeazzi or unacceptable displacement is present.+
  1. 1EscalationEscalate open, vascular and compartment findings before routine fixation planning.
  2. 2Fix radius and ulna to restore length, bow and rotation and confirm joint congruence intraoperatively.
  3. 3

Complications

01

Compartment syndrome

Pressure-related muscle and nerve ischaemia can cause necrosis, renal injury and Volkmann contracture if decompression is delayed.

02

Missed joint dislocation

Persistent radial-head or distal-radioulnar malalignment causes chronic pain, mechanical instability and restricted forearm rotation despite satisfactory shaft union.

03

Nonunion or synostosis

Open injury, infection, poor mechanics or heterotopic bone between radius and ulna can prevent union or eliminate rotation.

04

Nerve injury

Posterior interosseous, median, anterior interosseous or ulnar dysfunction may result from displacement, swelling or operative treatment.

Monitoring and follow-up

  • Repeat compartment, pulse and named nerve findings after reduction, casting, transfer and surgery.
  • Check cast pressure and finger colour, movement and sensation as swelling evolves.
  • Confirm radial-head and distal-radioulnar congruence on every relevant follow-up image.
  • Measure pronation and supination as well as elbow and wrist flexion and extension.
  • Investigate persistent fracture pain, motion loss or infection for nonunion, malunion or synostosis.

Special situations

One break implies another

Disruption of the forearm ring may be bony at one site and ligamentous at the opposite radioulnar joint.

Radiocapitellar line is age-proof

On a true view, a line through the radial neck should intersect the capitellum even in a young child.

Union can still rotate poorly

Restoring length without radial bow and rotational alignment can leave major pronation and supination loss.

Pulses do not clear compartments

Microvascular muscle ischaemia develops while major arterial pulses can remain palpable.

Common pitfalls

  1. 01

    Taking a focused fracture image that omits elbow or wrist.

  2. 02

    Fixing an ulnar fracture without confirming radial-head reduction.

  3. 03

    Calling a radial-shaft fracture isolated without assessing the distal radioulnar joint.

  4. 04

    Accepting union as success despite marked rotational malalignment.

  5. 05

    Missing compartment syndrome because the hand remains warm and perfused.

A child with plastic deformation or subtle ulnar bow can have radial-head dislocation despite an inconspicuous fracture line.
Document postoperative nerve status, movement, loading, wound and radiographic review.
03Child or stable patternReduce and monitor alignmentRemodelling and stable closed treatment are appropriate.+
  1. 1Achieve a gentle closed reduction and cast without excessive swelling pressure.
  2. 2Confirm radiocapitellar and distal-radioulnar relationships immediately and at early follow-up.
  3. 3EscalationRepeat neurovascular checks and escalate loss of position, rotation or joint congruence.
Key medicines and prescribing safety2 treatments · regimens, roles and cautions+
Provides baseline analgesia during splintage and rehabilitation.

Paracetamol for adult forearm pain

An adult may take 500 mg to 1 g orally when needed, never repeating before 4 hours and never exceeding 4 g across 24 hours.

Reduce the ceiling with low body weight or hepatic risk and count combination medicines.

Reduces infection risk before formal wound excision and fixation.

Intravenous open-fracture prophylaxis

Give the network-approved intravenous agent and dose as soon as possible and within 1 hour, adjusted for allergy, renal function and contamination.

Do not wait for cultures and do not substitute prolonged antibiotics for adequate orthoplastic treatment.