High-yield overview

Physis | articular surface | CT | 2 mm threshold | growth surveillance

5%Approximate share of all paediatric fractures

15-20%Share of physeal injuries involving the distal tibia

2 mmCommon intra-articular reduction threshold

12 monthsMinimum follow-up for high-risk medial malleolus bars

Working Groups

Stable extra-articular

PatternUndisplaced distal fibula or distal tibial physeal injury without joint incongruity.

TreatmentCast, early review and growth-risk counselling where relevant.

Displaced physeal

PatternSalter-Harris I/II or displaced fibular/tibial physeal injury.

TreatmentGentle reduction; fixation if unstable or reduction is blocked.

Intra-articular

PatternSalter-Harris III/IV medial malleolus or distal tibial epiphyseal fracture.

TreatmentCT-based assessment and anatomical reduction when displaced.

Transitional

PatternTillaux or triplane injury during asymmetric distal tibial physeal closure.

TreatmentCT defines fragments; less than 2 mm may be casted, greater than 2 mm usually needs anatomical reduction.

Critical Must-Knows

The distal tibial physis closes asymmetrically. Central closure occurs first, then medial, then lateral; this creates Tillaux and triplane patterns.
Plain radiographs can underestimate displacement. CT is important for intra-articular and transitional fractures.
Greater than 2 mm intra-articular gap or step is the practical threshold for anatomical reduction in Tillaux, triplane and SH-III/IV patterns.
Repeated forceful reductions can harm the physis. If tissue blocks reduction, change strategy rather than persist.
Growth arrest is not rare in high-risk patterns. Medial malleolus and high-energy distal tibial physeal injuries need surveillance.

Clinical Pearls

"
Ask for AP, mortise and true lateral ankle views; add tibia/fibula views when proximal pain or syndesmotic concern exists.
"
Tillaux is an anterolateral epiphyseal avulsion by the anterior inferior tibiofibular ligament.
"
Triplane is a multiplanar SH-IV pattern: epiphyseal, physeal and metaphyseal components.
"
A medial malleolus SH-III/IV fracture is a growth-arrest risk even after apparently good reduction.

Do not read paediatric ankle fractures like adult ankle fractures

A child with an ankle fracture has a physis, partly closing growth plate and different failure points. The adult question is often syndesmosis and malleoli; the paediatric question is physis, articular surface, remaining growth, reduction quality and growth arrest.

Paediatric ankle fracture pathway — A safe paediatric ankle pathway begins with skin, swelling, perfusion and compartment risk, then uses AP, mortise, lateral and selective CT to classify the injury and choose cast, reduction, fixation and growth surveillance.Credit: Original OrthoVellum illustration

At a Glance: What Decides Treatment?

Clinical Question	What To Check	Why It Changes Management
Is the ankle safe?	Open injury, skin tenting, swelling, pulses, sensation, pain escalation and compartment concern.	Unsafe soft tissues or compartment concern override routine casting pathways.
Is the joint involved?	Mortise view, articular step or gap, SH-III/IV pattern, Tillaux or triplane fracture.	Intra-articular incongruity usually needs CT and anatomical reduction.
Is the physis displaced?	Displacement, angulation, rotation, residual gap and tissue interposition.	Displaced physeal injuries need reduction; blocked or unstable reductions may need fixation.
How much growth remains?	Chronological age, skeletal maturity, remaining distal tibial growth and fracture type.	Higher remaining growth increases the importance of growth-arrest surveillance and counselling.
Is this a transitional fracture?	Adolescent age, external rotation mechanism, anterolateral epiphyseal fragment or multiplanar triplane geometry.	CT planning determines whether casting, percutaneous fixation or open reduction is safest.

Rapid Recall

CMLPhyseal closure	TILLTillaux	STEPSurgery threshold
C Central first Initial distal tibial physeal closure begins centrally.	T Transitional age Occurs during asymmetric physeal closure.	S Step Articular step-off on CT.
M Medial next Medial closure leaves lateral physis vulnerable.	I Intra-articular SH-III pattern through epiphysis and physis.	T Two millimetres Common decision threshold for intra-articular injury.
L Lateral last Anterolateral fragment becomes the Tillaux fragment.	L Lateral fragment Anterolateral epiphyseal fragment.	E Epiphysis Epiphyseal screws should avoid crossing the physis where possible.
	L Ligament pull AITFL traction creates the fragment.	P Plan CT Plan screw trajectory and approach from CT.
Central, medial, lateral closure creates transitional patterns.	Tillaux is the lateral epiphyseal avulsion.	STEP greater than 2 mm usually needs anatomical reduction.

Overview/Epidemiology

Paediatric ankle fractures account for about 5% of all paediatric fractures and the distal tibial physis is one of the most important lower-limb growth plates injured in children. Management is high-stakes because the same injury can affect the joint surface, the physis or both.

The typical presentation is a child or adolescent with ankle pain, swelling and inability to weight bear after a twisting injury, fall, sport injury or higher-energy trauma. The key is to avoid the adult-ankle shortcut. In children, the ligament may remain intact while the physis or epiphysis fails. In adolescents, asymmetric distal tibial physeal closure creates transitional injuries such as Tillaux and triplane fractures.

The safe management sequence is:

The Surgeon’s Sequence

Step	Question	Action
Safety	Is there open injury, threatened skin, vascular compromise or compartment concern?	Escalate urgently before routine fracture planning.
Pattern	Is this fibular, distal tibial physeal, medial malleolus, Tillaux or triplane?	Classify by physis and joint involvement.
Imaging	Can plain radiographs define the joint surface and fracture geometry?	Use CT for intra-articular and transitional fractures.
Reduction	Is alignment, physis and articular surface acceptable?	Cast, reduce, percutaneously fix or open depending on displacement and stability.
Follow-up	Is there remaining growth or high-risk medial malleolus injury?	Monitor for physeal bar, angular deformity and leg-length difference.

Surgically Relevant Anatomy

The distal tibial physis contributes meaningfully to tibial growth and closes in an asymmetric pattern. Central closure begins first, followed by medial closure, with lateral closure last. During this transition, the partially closed physis cannot dissipate rotational force evenly.

The anterior inferior tibiofibular ligament attaches to the anterolateral distal tibial epiphysis. When the medial physis is closing and the lateral physis remains open, external rotation can avulse the anterolateral epiphyseal fragment: the Tillaux pattern. If the fracture propagates through the epiphysis, physis and metaphysis in different planes, the result is a triplane fracture.

Medial malleolus SH-III and SH-IV fractures cross the epiphysis and physis and can damage the germinal layer. Even small residual displacement may matter because the medial distal tibial physis can form a physeal bar.

Distal tibia

Physis plus joint surface. Reduction must protect both growth and articular congruity.

Distal fibula

Often lower-risk, but do not miss syndesmotic injury, physeal displacement or associated distal tibial injury.

Medial malleolus

SH-III/IV medial injuries carry meaningful physeal-bar risk and need longer surveillance.

Pathophysiology

The injury pattern depends on the child's age, mechanism and stage of physeal closure.

Why The Fracture Pattern Occurs

Mechanism	Typical Pattern	Management Consequence
Supination-inversion	Distal fibular physeal injury or medial distal tibial injury depending force and age.	Examine both malleoli; do not assume lateral pain means simple sprain.
External rotation in an adolescent	Tillaux or triplane fracture during asymmetric distal tibial physeal closure.	CT defines the fragment and articular displacement.
High-energy axial or rotational trauma	Displaced distal tibial physeal injury, SH-IV fracture or complex triplane pattern.	Higher risk of growth disturbance and worse functional outcome.
Direct medial injury	Medial malleolus SH-III/IV fracture.	Anatomical reduction and growth-arrest surveillance are central.
Ligament-equivalent failure	The physis fails before adult-style ligament rupture.	Treatment decisions must consider growth plate and remaining growth.

Classification

Distal Tibial Physeal Groups

Type	Pattern	Treatment Meaning
SH-I	Through the physis; may be radiographically subtle.	Treat displacement and clinical tenderness; follow if distal tibia involved.
SH-II	Physis plus metaphyseal fragment.	Closed reduction if displaced; open if tissue blocks reduction.
SH-III	Epiphyseal intra-articular fracture extending to physis.	CT and anatomical reduction if displaced.
SH-IV	Epiphysis, physis and metaphysis.	CT-defined reduction and fixation; growth arrest risk.
SH-V	Crush injury to physis, often diagnosed late.	High suspicion and growth surveillance.

Clinical Assessment

History

Ask for mechanism, energy, ability to weight bear, exact pain location, time since injury, reduction attempt, open wound, skin tenting, paraesthesia and prior ankle injury. Sporting adolescents with external rotation mechanisms are the classic group for transitional fractures.

Examination

Look, Feel, Move

Step	How To Do It	Positive Finding
Look	Inspect swelling, bruising, deformity, skin tenting, open wounds and foot position.	Threatened skin, open injury or marked deformity needs urgent reduction or operative escalation.
Feel	Palpate distal tibial physis, medial malleolus, lateral malleolus, syndesmosis, proximal fibula, base of fifth metatarsal and midfoot.	Focal physeal or medial malleolar tenderness changes imaging and follow-up.
Move	Assess active toe motion and gentle ankle motion only if safe; do not stress a displaced fracture.	Painful block or gross instability supports significant fracture or joint involvement.
Neurovascular	Check dorsalis pedis/posterior tibial pulses, capillary refill, sensation in superficial/deep peroneal, tibial, sural and saphenous distributions.	Document before and after reduction.
Compartment risk	Assess escalating pain, pain with passive toe stretch, tense compartments and analgesic requirement.	Compartment concern is an emergency even if the X-ray looks manageable.

Differential Diagnosis

The trap in children is the radiographically subtle injury. A tender physis with a "normal" film is a fracture until proven otherwise, and a presumed sprain in a skeletally immature ankle should be treated with suspicion.

Differentiating the Paediatric Ankle Injury

Diagnosis	Discriminating Features	How To Confirm or Exclude
Distal fibular SH-I	Focal physeal tenderness with a near-normal radiograph in a younger child after inversion.	Clinical diagnosis; treat tenderness over the physis as a fracture and review; MRI only if symptoms persist.
Lateral ligament sprain	Tenderness anterior to and below the malleolus rather than over the physis, usually an older adolescent.	More likely once the physis has closed; do not over-call sprain when physeal tenderness is present.
Tillaux fracture	Adolescent, external rotation, anterolateral epiphyseal tenderness.	Mortise radiograph plus CT for the anterolateral fragment and articular gap.
Triplane fracture	Adolescent with multiplanar pain; the metaphyseal fragment may be missed on the AP view.	CT defines epiphyseal, physeal and metaphyseal components.
Medial malleolus SH-III/IV	Medial joint-line tenderness, intra-articular line on the mortise view.	CT for displacement; flag for growth-arrest surveillance.
Osteochondral lesion of the talus	Persistent deep ankle pain, catching or effusion after a twist with normal alignment.	MRI; consider when symptoms outlast the expected fracture or sprain course.
Proximal fibula (Maisonneuve-type)	Proximal fibular tenderness with a syndesmotic or medial ankle injury.	Full-length tibia/fibula radiographs; check medial clear space and syndesmosis.

Investigations

What to request

AP, mortise and true lateral ankle radiographs.
Tibia/fibula views if proximal fibular pain, high-energy mechanism, syndesmotic concern or Maisonneuve-type pattern is possible.
Foot radiographs if midfoot, base of fifth metatarsal or talar tenderness is present.
CT for suspected Tillaux, triplane, SH-III/IV, intra-articular displacement, unclear fracture geometry or pre-operative planning.
MRI is not routine for clear fractures, but may help when radiographs are negative and symptoms remain disproportionate or when occult physeal injury is a concern.

Tillaux Salter-Harris III distal tibial fracture radiograph series — Distal tibial epiphyseal fracture series consistent with a Tillaux/SH-III pattern. Plain films suggest the diagnosis, but CT is often needed to measure the articular gap, step and fragment geometry accurately.Credit: Kyonghun Chong via Wikimedia Commons, CC-BY-SA-4.0

Medial malleolus Salter-Harris III fracture and distal tibial physis — Medial malleolus SH-III/IV injuries are important because they cross the physis and joint. This image includes source arrows over the medial epiphyseal fracture region and distal tibial physis; the treatment issue is exact reduction plus growth surveillance.Credit: James Heilman, MD via Wikimedia Commons, CC-BY-SA-3.0

How to interpret

Radiographic and CT Checklist

Feature	How To Assess	Treatment Meaning
Mortise congruity	Check medial clear space, talar shift and joint line.	Incongruity suggests unstable or intra-articular injury.
Physeal displacement	Measure residual gap, translation and angulation after reduction.	Persistent gap may indicate periosteal/tissue interposition.
Articular step/gap	Measure on CT in coronal, sagittal and axial planes.	Greater than 2 mm is the common threshold for anatomical reduction.
Tillaux fragment	Look for anterolateral epiphyseal fragment attached to AITFL.	Screw trajectory is usually planned perpendicular to the fracture line while avoiding the physis when possible.
Triplane geometry	Define epiphyseal, physeal and metaphyseal components on CT.	Determines whether closed/percutaneous fixation is enough or open reduction is needed.
Medial malleolus	Assess SH-III/IV line and residual displacement.	High physeal-bar risk; reduction quality and follow-up matter.

Management

Paediatric ankle treatment choices — Treatment choices are organised by stability, displacement and joint involvement. The key distinction is that displaced extra-articular physeal injuries need safe reduction, while intra-articular/transitional injuries need CT-defined articular congruity.Credit: Original OrthoVellum illustration

Immediate Management

Priority	Action	Reason
Analgesia and elevation	Control pain, elevate and splint.	Reduces swelling and allows safe reassessment.
Unsafe soft tissues	Urgent reduction for skin tenting or severe deformity; urgent theatre for open injury.	Prevents skin compromise and contamination complications.
Neurovascular check	Document pulses, capillary refill and sensation before and after reduction.	Identifies injury-related or iatrogenic deterioration.
Imaging after reduction	Repeat AP, mortise and lateral films after any reduction.	Confirms alignment and residual displacement.

Operative Technique

Principles

The operation should reduce the joint surface, respect the physis, avoid repeated traumatic manipulation and provide enough stability for safe healing. CT determines the approach and screw trajectory in Tillaux and triplane injuries.

Technique by Pattern

Operation	PIPADRAW Sequence	Pitfalls
Closed reduction and casting	Position supine; analgesia/anaesthesia; traction and reverse mechanism; check AP/mortise/lateral; cast; repeat films.	Repeated forceful attempts can injure the physis or soft tissues.
Percutaneous fixation	Supine; image intensifier AP/mortise/lateral; reduce closed; insert cannulated screw or K-wire according to fragment; confirm joint and physis.	Do not accept a poor reduction just because fixation is percutaneous.
Tillaux ORIF	Anterolateral approach if closed reduction fails; identify fragment; clear interposed tissue; reduce anterolateral epiphysis; fix with epiphyseal screw parallel to joint/physis where possible.	Screw trajectory must not enter the joint; CT planning is essential.
Triplane fixation	CT plan; reduce epiphyseal joint component first; fix epiphyseal fragment; then reduce/fix metaphyseal component if needed.	Treating only the metaphyseal fragment can leave the joint incongruent.
Medial malleolus fixation	Medial approach; protect saphenous structures; reduce SH-III/IV fragment anatomically; fix with screw trajectory planned to minimise physeal damage.	Residual displacement increases bar risk; follow-up is mandatory.

Intra-operative reduction check

For Tillaux and triplane injuries, the operative endpoint is not just a screw in bone. The endpoint is a congruent mortise, less than 2 mm residual articular displacement, stable fixation and a documented plan for growth follow-up.

Post-Operative Care and Rehabilitation

Aftercare

Situation	Typical Plan	What To Monitor
Cast treatment	Non-weight bearing initially, then progress according to pain, healing and local protocol.	Loss of reduction, pain, swelling and late growth disturbance.
Percutaneous fixation	Protected non-weight bearing, wound/pin review if relevant, radiographs.	Reduction maintenance, hardware symptoms and healing.
ORIF	Below-knee immobilisation, non-weight bearing until early healing, then progressive motion.	Joint congruity, screw position, infection, stiffness and physeal bar.
High growth remaining	Serial standing alignment and ankle radiographs.	Physeal bar, angular deformity and leg-length difference.

Children with intra-articular displacement, high-energy trauma, medial malleolus injury or meaningful remaining growth should not disappear after fracture union. They need a surveillance plan until growth arrest risk is acceptably low.

Complications and Failure Management

Growth-arrest surveillance after paediatric ankle fracture — Growth surveillance is a management pathway, not a single clinic visit. High-risk injuries need fracture follow-up, serial radiographs, physeal-bar investigation when suspected and treatment chosen by bar size, deformity and growth remaining.Credit: Original OrthoVellum illustration

Complications

Complication	Risk Pattern	Management
Physeal bar / growth arrest	Medial malleolus SH-III/IV, high-energy distal tibial physis, residual displacement.	Serial radiographs; consider bar resection, guided growth, epiphysiodesis or osteotomy depending bar size and growth remaining.
Angular deformity	Partial distal tibial arrest.	Measure mechanical/anatomic axis and ankle orientation; guided growth or osteotomy if progressive/significant.
Leg-length difference	Complete or partial arrest with meaningful remaining growth.	Scanogram, bone age and prediction; shoe raise, epiphysiodesis or length correction depending magnitude.
Post-traumatic arthritis	Residual intra-articular incongruity after SH-III/IV, Tillaux or triplane fracture.	Prevention is anatomical reduction; established arthritis is managed symptomatically or reconstructively.
Stiffness	Prolonged immobilisation or intra-articular injury.	Motion after healing, physiotherapy and gradual return to activity.
Compartment syndrome	High-energy injury, severe swelling, displaced distal tibial injury.	Emergency recognition and fasciotomy if diagnosed.

Evidence Signals

Guidelines to management

Review and management guideline

Key Findings:

Paediatric ankle fractures represent about 5% of all paediatric fractures.
Distal tibial physeal injuries account for approximately 15-20% of all physeal injuries.
CT is recommended with low threshold for suspected intra-articular or transitional fractures.
Intra-articular displacement greater than 2 mm needs anatomical reduction and stabilisation.

Clinical Implication: Use CT early when the joint surface or transitional fracture geometry is uncertain.

Limitation: Guideline-level synthesis based on literature and trauma-centre experience.

Source: Venkatadass et al., Indian Journal of Orthopaedics, 2021

Verify on PubMed (PMID 33569097)

Physeal ankle fracture review

Review

Key Findings:

Distal tibial physeal fractures require attention to growth arrest risk.
Classification, displacement and remaining growth guide treatment.
Anatomic reduction is central for intra-articular patterns.

Clinical Implication: A growth-plate injury plan must include reduction quality and follow-up.

Limitation: Narrative review; thresholds should be applied with fracture-specific judgement.

Source: Wuerz and Gurd, Journal of the AAOS, 2013

Verify on PubMed (PMID 23545729)

Dias-Tachdjian classification (landmark)

Landmark classification study

Key Findings:

Analysed 71 paediatric ankle fractures and proposed a mechanism-based classification by foot position and direction of force.
Supination-inversion was the commonest mechanism, present in almost half of cases.
Correlation with the Salter-Harris system is essential because varus deformity is common after SH-III and SH-IV injuries.

Clinical Implication: Knowing the injury mechanism guides closed reduction by reversing the deforming force, while Salter-Harris type still drives growth-arrest risk.

Limitation: Pre-CT 1978 cohort; mechanism-based grading does not replace CT articular assessment in transitional fractures.

Source: Dias and Tachdjian, Clinical Orthopaedics and Related Research, 1978

Verify on PubMed (PMID 103673)

Controversies and Areas of Uncertainty

Examiners reward a candidate who can hold a clear default position while acknowledging genuine debate. The honest answer to most of these is anatomical reduction of the displaced joint, with the nuance below.

Where the Evidence Is Still Debated

Question	What Is Agreed	What Remains Uncertain
How much residual gap is acceptable?	Greater than 2 mm displacement on CT is the practical threshold for anatomical reduction.	Outcomes data (Choudhry/Crawford) suggest displacement under about 2.5 mm after sound reduction is tolerated; the safe upper limit is not defined.
Closed percutaneous versus open fixation for triplane?	The articular surface must be congruent however it is achieved.	Closed reduction with percutaneous screws gives good results when reduction is perfect, but the threshold to convert to open is judgement-based.
Is CT needed for every transitional fracture?	CT is standard for SH-III/IV, Tillaux and triplane planning.	Radiation stewardship versus information gain in clearly undisplaced patterns; some centres use limited-sequence MRI.
Should screws cross the physis?	Avoid crossing the physis where the geometry allows.	In transitional fractures the physis is closing, so a transphyseal screw is often acceptable; in young children it is avoided.
How long to follow for growth arrest?	Medial malleolus SH-III/IV and high-energy distal tibial injuries need prolonged surveillance.	Optimal frequency and total duration vary; at least 12 months is supported for medial malleolus injuries, longer with substantial growth remaining.

Guidelines, Registries & Global Practice

Global epidemiology

Paediatric ankle fractures account for about 5% of all paediatric fractures, and distal tibial physeal injuries make up roughly 15-20% of all physeal injuries, making the distal tibia the most commonly injured lower-limb physis in children. Transitional fractures (Tillaux and triplane) cluster in the roughly 18-month window before physeal closure, which completes at about 14 years in girls and 16 years in boys. Boys are affected more often overall; girls sustain transitional fractures at a younger age than boys.

Side-by-side guidance

There is no single global ankle-specific paediatric guideline; practice is built from major-society principles plus the paediatric trauma literature. The points below describe how the relevant bodies frame the same problem.

How Major Bodies Frame Paediatric Ankle and Physeal Injury

Body / Source	Emphasis	Practical Position
AO Foundation (Paediatric)	Mechanism, Salter-Harris pattern and physis-sparing fixation.	Anatomical reduction of intra-articular fragments; implants chosen to minimise physeal injury; CT for transitional patterns.
AAOS / POSNA literature (US)	Classification-driven management and growth-arrest risk.	Low threshold for CT in intra-articular and transitional fractures; surveillance for premature physeal closure.
BOA / BOAST (UK, paediatric trauma principles)	Timely senior-led care, neurovascular documentation and open-fracture pathways.	Soft-tissue and neurovascular assessment first; defined escalation for open or deformed injuries.
EFORT / European paediatric trauma consensus	Standardised physeal-injury assessment and follow-up.	Reduce the joint, protect the physis and follow to skeletal maturity in high-risk patterns.

Registries

Unlike arthroplasty, paediatric ankle fractures are not tracked by implant registries; the evidence base is observational cohorts and systematic reviews (for example the 2025 triplane review pooling 34 studies). National paediatric trauma networks and major-trauma audits, rather than implant registries, are the closest surveillance structures.

High-resource versus limited-resource practice

Practice Variation by Setting

Element	Well-resourced setting	Limited-resource setting
Imaging	CT routine for transitional and SH-III/IV fractures; MRI available for occult injury.	Reliance on good-quality mortise and lateral radiographs; intra-operative arthrogram or image intensifier to judge congruity.
Fixation	Cannulated screws and image intensifier readily available.	K-wires and careful closed reduction where screws are scarce; sound reduction still prioritised.
Follow-up	Structured growth-arrest surveillance to maturity.	Surveillance limited by access; clear safety-netting and return advice become essential.

Clinical Scenarios

Use these scenarios to practise clinical reasoning and management decisions

CLINICAL SCENARIOStandard

CLINICAL PROMPT

"A 14-year-old has lateral ankle pain after an external rotation injury. X-rays suggest a Tillaux fracture. CT shows 1.5 mm articular gap."

PRACTICAL APPROACH

This is a juvenile Tillaux fracture with less than 2 mm displacement on CT. I would confirm the ankle is neurovascularly intact and there is no syndesmotic or associated injury. Because the joint remains acceptably congruent, non-operative treatment in a below-knee cast with initial non-weight bearing and close follow-up is reasonable. I would repeat radiographs to ensure no displacement and counsel about symptoms, return precautions and the low but real need for follow-up until safe.

KEY CLINICAL POINTS

Tillaux is SH-III anterolateral epiphyseal injury

CT defines displacement

Less than 2 mm may be treated non-operatively

Follow-up remains important

COMMON PITFALLS

Skipping CT

Calling it an adult syndesmotic avulsion

Ignoring growth and articular follow-up

FURTHER QUESTIONS

"What changes if CT shows 3 mm displacement?"

CLINICAL SCENARIOChallenging

CLINICAL PROMPT

"A 13-year-old has a triplane ankle fracture. CT shows a displaced epiphyseal component with 4 mm joint step and a metaphyseal fragment."

PRACTICAL APPROACH

This is a displaced intra-articular transitional fracture. I would perform CT-based operative planning. The treatment goal is anatomical reduction of the epiphyseal articular component first, then reduction and fixation of the metaphyseal component if needed. Depending on reducibility, this may be closed reduction and percutaneous screw fixation or open reduction through an approach determined by the fragment geometry. Screws should be planned to avoid the joint and minimise physeal injury where possible. Post-operatively I would immobilise, keep non-weight bearing initially, monitor reduction and counsel regarding growth arrest and ankle stiffness.

KEY CLINICAL POINTS

Triplane is CT-planned

Joint reduction comes first

Greater than 2 mm step is unacceptable

Screw direction follows CT-defined fracture geometry

COMMON PITFALLS

Treating the metaphysis but leaving the joint incongruent

Using plain radiographs alone

Forgetting growth arrest surveillance

FURTHER QUESTIONS

"How do you choose percutaneous fixation versus open reduction?"

CLINICAL SCENARIOCritical

CLINICAL PROMPT

"A 10-year-old has a displaced medial malleolus SH-III fracture. It is reduced and fixed. At five months the radiograph shows asymmetric physeal closure."

PRACTICAL APPROACH

The concern is a medial distal tibial physeal bar causing partial growth arrest. I would assess symptoms, ankle alignment, standing radiographs, scanogram if leg length is relevant and bone age to estimate remaining growth. MRI or CT can define bar size and location. Management depends on remaining growth, bar size and deformity: observation if minimal and near maturity, bar resection if small with growth remaining, guided growth or epiphysiodesis for progression, and corrective osteotomy for established angular deformity.

KEY CLINICAL POINTS

Medial malleolus SH-III/IV injuries have physeal bar risk

Bars may appear months after injury

Define bar size, growth remaining and deformity

Treatment depends on growth remaining and deformity

COMMON PITFALLS

Discharging after fracture union only

Ignoring subtle asymmetric closure

Choosing bar resection without estimating growth remaining

FURTHER QUESTIONS

"What follow-up schedule would you arrange after the original injury?"

Paediatric Ankle Fractures: Decision Sheet

Clinical summary

Assess

•Check skin, swelling, pulses, sensation and compartment risk.
•Order AP, mortise and true lateral ankle radiographs.
•Add tibia/fibula views for proximal pain or syndesmotic concern.

Image

•Use CT for Tillaux, triplane, SH-III/IV or unclear intra-articular displacement.
•Measure articular step and gap on CT.
•Look specifically at the medial malleolus and distal tibial physis.

Treat

•Stable extra-articular injuries can usually be casted.
•Displaced physeal injuries need gentle reduction; fixation if unstable or blocked.
•Intra-articular/transitional injuries greater than 2 mm usually need anatomical reduction.

Follow

•Monitor high-risk injuries for growth arrest.
•Medial malleolus SH-III/IV injuries need prolonged surveillance.
•Treat physeal bar according to bar size, deformity and remaining growth.

Clinical Question

What To Check

Why It Changes Management

Is the ankle safe?

Open injury, skin tenting, swelling, pulses, sensation, pain escalation and compartment concern.

Unsafe soft tissues or compartment concern override routine casting pathways.

Is the joint involved?

Mortise view, articular step or gap, SH-III/IV pattern, Tillaux or triplane fracture.

Intra-articular incongruity usually needs CT and anatomical reduction.

Is the physis displaced?

Displacement, angulation, rotation, residual gap and tissue interposition.

Displaced physeal injuries need reduction; blocked or unstable reductions may need fixation.

How much growth remains?

Chronological age, skeletal maturity, remaining distal tibial growth and fracture type.

Higher remaining growth increases the importance of growth-arrest surveillance and counselling.

Is this a transitional fracture?

Adolescent age, external rotation mechanism, anterolateral epiphyseal fragment or multiplanar triplane geometry.

CT planning determines whether casting, percutaneous fixation or open reduction is safest.

CMLPhyseal closure

TILLTillaux

STEPSurgery threshold

Central first

Initial distal tibial physeal closure begins centrally.

Transitional age

Occurs during asymmetric physeal closure.

Step

Articular step-off on CT.

Medial next

Medial closure leaves lateral physis vulnerable.

Intra-articular

SH-III pattern through epiphysis and physis.

Two millimetres

Common decision threshold for intra-articular injury.

Lateral last

Anterolateral fragment becomes the Tillaux fragment.

Lateral fragment

Anterolateral epiphyseal fragment.

Epiphysis

Epiphyseal screws should avoid crossing the physis where possible.

Ligament pull

AITFL traction creates the fragment.

Plan CT

Plan screw trajectory and approach from CT.

Central, medial, lateral closure creates transitional patterns.

Tillaux is the lateral epiphyseal avulsion.

STEP greater than 2 mm usually needs anatomical reduction.

Step

Question

Action

Safety

Is there open injury, threatened skin, vascular compromise or compartment concern?

Escalate urgently before routine fracture planning.

Pattern

Is this fibular, distal tibial physeal, medial malleolus, Tillaux or triplane?

Classify by physis and joint involvement.

Imaging

Can plain radiographs define the joint surface and fracture geometry?

Use CT for intra-articular and transitional fractures.

Reduction

Is alignment, physis and articular surface acceptable?

Cast, reduce, percutaneously fix or open depending on displacement and stability.

Follow-up

Is there remaining growth or high-risk medial malleolus injury?

Monitor for physeal bar, angular deformity and leg-length difference.

Mechanism

Typical Pattern

Management Consequence

Supination-inversion

Distal fibular physeal injury or medial distal tibial injury depending force and age.

Examine both malleoli; do not assume lateral pain means simple sprain.

External rotation in an adolescent

Tillaux or triplane fracture during asymmetric distal tibial physeal closure.

CT defines the fragment and articular displacement.

High-energy axial or rotational trauma

Displaced distal tibial physeal injury, SH-IV fracture or complex triplane pattern.

Higher risk of growth disturbance and worse functional outcome.

Direct medial injury

Medial malleolus SH-III/IV fracture.

Anatomical reduction and growth-arrest surveillance are central.

Ligament-equivalent failure

The physis fails before adult-style ligament rupture.

Treatment decisions must consider growth plate and remaining growth.

Type

Pattern

Treatment Meaning

SH-I

Through the physis; may be radiographically subtle.

Treat displacement and clinical tenderness; follow if distal tibia involved.

SH-II

Physis plus metaphyseal fragment.

Closed reduction if displaced; open if tissue blocks reduction.

SH-III

Epiphyseal intra-articular fracture extending to physis.

CT and anatomical reduction if displaced.

SH-IV

Epiphysis, physis and metaphysis.

CT-defined reduction and fixation; growth arrest risk.

SH-V

Crush injury to physis, often diagnosed late.

High suspicion and growth surveillance.

Step

How To Do It

Positive Finding

Look

Inspect swelling, bruising, deformity, skin tenting, open wounds and foot position.

Threatened skin, open injury or marked deformity needs urgent reduction or operative escalation.

Feel

Palpate distal tibial physis, medial malleolus, lateral malleolus, syndesmosis, proximal fibula, base of fifth metatarsal and midfoot.

Focal physeal or medial malleolar tenderness changes imaging and follow-up.

Move

Assess active toe motion and gentle ankle motion only if safe; do not stress a displaced fracture.

Painful block or gross instability supports significant fracture or joint involvement.

Neurovascular

Check dorsalis pedis/posterior tibial pulses, capillary refill, sensation in superficial/deep peroneal, tibial, sural and saphenous distributions.

Document before and after reduction.

Compartment risk

Assess escalating pain, pain with passive toe stretch, tense compartments and analgesic requirement.

Compartment concern is an emergency even if the X-ray looks manageable.

Diagnosis

Discriminating Features

How To Confirm or Exclude

Distal fibular SH-I

Focal physeal tenderness with a near-normal radiograph in a younger child after inversion.

Clinical diagnosis; treat tenderness over the physis as a fracture and review; MRI only if symptoms persist.

Lateral ligament sprain

Tenderness anterior to and below the malleolus rather than over the physis, usually an older adolescent.

More likely once the physis has closed; do not over-call sprain when physeal tenderness is present.

Tillaux fracture

Adolescent, external rotation, anterolateral epiphyseal tenderness.

Mortise radiograph plus CT for the anterolateral fragment and articular gap.

Triplane fracture

Adolescent with multiplanar pain; the metaphyseal fragment may be missed on the AP view.

CT defines epiphyseal, physeal and metaphyseal components.

Medial malleolus SH-III/IV

Medial joint-line tenderness, intra-articular line on the mortise view.

CT for displacement; flag for growth-arrest surveillance.

Osteochondral lesion of the talus

Persistent deep ankle pain, catching or effusion after a twist with normal alignment.

MRI; consider when symptoms outlast the expected fracture or sprain course.

Proximal fibula (Maisonneuve-type)

Proximal fibular tenderness with a syndesmotic or medial ankle injury.

Full-length tibia/fibula radiographs; check medial clear space and syndesmosis.

Feature

How To Assess

Treatment Meaning

Mortise congruity

Check medial clear space, talar shift and joint line.

Incongruity suggests unstable or intra-articular injury.

Physeal displacement

Measure residual gap, translation and angulation after reduction.

Persistent gap may indicate periosteal/tissue interposition.

Articular step/gap

Measure on CT in coronal, sagittal and axial planes.

Greater than 2 mm is the common threshold for anatomical reduction.

Tillaux fragment

Look for anterolateral epiphyseal fragment attached to AITFL.

Screw trajectory is usually planned perpendicular to the fracture line while avoiding the physis when possible.

Triplane geometry

Define epiphyseal, physeal and metaphyseal components on CT.

Determines whether closed/percutaneous fixation is enough or open reduction is needed.

Medial malleolus

Assess SH-III/IV line and residual displacement.

High physeal-bar risk; reduction quality and follow-up matter.

Priority

Action

Reason

Analgesia and elevation

Control pain, elevate and splint.

Reduces swelling and allows safe reassessment.

Unsafe soft tissues

Urgent reduction for skin tenting or severe deformity; urgent theatre for open injury.

Prevents skin compromise and contamination complications.

Neurovascular check

Document pulses, capillary refill and sensation before and after reduction.

Identifies injury-related or iatrogenic deterioration.

Imaging after reduction

Repeat AP, mortise and lateral films after any reduction.

Confirms alignment and residual displacement.

Operation

PIPADRAW Sequence

Pitfalls

Closed reduction and casting

Position supine; analgesia/anaesthesia; traction and reverse mechanism; check AP/mortise/lateral; cast; repeat films.

Repeated forceful attempts can injure the physis or soft tissues.

Percutaneous fixation

Supine; image intensifier AP/mortise/lateral; reduce closed; insert cannulated screw or K-wire according to fragment; confirm joint and physis.

Do not accept a poor reduction just because fixation is percutaneous.

Tillaux ORIF

Anterolateral approach if closed reduction fails; identify fragment; clear interposed tissue; reduce anterolateral epiphysis; fix with epiphyseal screw parallel to joint/physis where possible.

Screw trajectory must not enter the joint; CT planning is essential.

Triplane fixation

CT plan; reduce epiphyseal joint component first; fix epiphyseal fragment; then reduce/fix metaphyseal component if needed.

Treating only the metaphyseal fragment can leave the joint incongruent.

Medial malleolus fixation

Medial approach; protect saphenous structures; reduce SH-III/IV fragment anatomically; fix with screw trajectory planned to minimise physeal damage.

Residual displacement increases bar risk; follow-up is mandatory.

Situation

Typical Plan

What To Monitor

Cast treatment

Non-weight bearing initially, then progress according to pain, healing and local protocol.

Loss of reduction, pain, swelling and late growth disturbance.

Percutaneous fixation

Protected non-weight bearing, wound/pin review if relevant, radiographs.

Reduction maintenance, hardware symptoms and healing.

ORIF

Below-knee immobilisation, non-weight bearing until early healing, then progressive motion.

Joint congruity, screw position, infection, stiffness and physeal bar.

High growth remaining

Serial standing alignment and ankle radiographs.

Physeal bar, angular deformity and leg-length difference.

Complication

Risk Pattern

Management

Physeal bar / growth arrest

Medial malleolus SH-III/IV, high-energy distal tibial physis, residual displacement.

Serial radiographs; consider bar resection, guided growth, epiphysiodesis or osteotomy depending bar size and growth remaining.

Angular deformity

Partial distal tibial arrest.

Measure mechanical/anatomic axis and ankle orientation; guided growth or osteotomy if progressive/significant.

Leg-length difference

Complete or partial arrest with meaningful remaining growth.

Scanogram, bone age and prediction; shoe raise, epiphysiodesis or length correction depending magnitude.

Post-traumatic arthritis

Residual intra-articular incongruity after SH-III/IV, Tillaux or triplane fracture.

Prevention is anatomical reduction; established arthritis is managed symptomatically or reconstructively.

Stiffness

Prolonged immobilisation or intra-articular injury.

Motion after healing, physiotherapy and gradual return to activity.

Compartment syndrome

High-energy injury, severe swelling, displaced distal tibial injury.

Emergency recognition and fasciotomy if diagnosed.

Guidelines to management

Review and management guideline

Key Findings:

Paediatric ankle fractures represent about 5% of all paediatric fractures.
Distal tibial physeal injuries account for approximately 15-20% of all physeal injuries.
CT is recommended with low threshold for suspected intra-articular or transitional fractures.
Intra-articular displacement greater than 2 mm needs anatomical reduction and stabilisation.

Clinical Implication: Use CT early when the joint surface or transitional fracture geometry is uncertain.

Limitation: Guideline-level synthesis based on literature and trauma-centre experience.

Source: Venkatadass et al., Indian Journal of Orthopaedics, 2021

Verify on PubMed (PMID 33569097)

Physeal ankle fracture review

Review

Key Findings:

Distal tibial physeal fractures require attention to growth arrest risk.
Classification, displacement and remaining growth guide treatment.
Anatomic reduction is central for intra-articular patterns.

Clinical Implication: A growth-plate injury plan must include reduction quality and follow-up.

Limitation: Narrative review; thresholds should be applied with fracture-specific judgement.

Source: Wuerz and Gurd, Journal of the AAOS, 2013

Verify on PubMed (PMID 23545729)

Dias-Tachdjian classification (landmark)

Landmark classification study

Key Findings:

Analysed 71 paediatric ankle fractures and proposed a mechanism-based classification by foot position and direction of force.
Supination-inversion was the commonest mechanism, present in almost half of cases.
Correlation with the Salter-Harris system is essential because varus deformity is common after SH-III and SH-IV injuries.

Clinical Implication: Knowing the injury mechanism guides closed reduction by reversing the deforming force, while Salter-Harris type still drives growth-arrest risk.

Limitation: Pre-CT 1978 cohort; mechanism-based grading does not replace CT articular assessment in transitional fractures.

Source: Dias and Tachdjian, Clinical Orthopaedics and Related Research, 1978

Verify on PubMed (PMID 103673)

Question

What Is Agreed

What Remains Uncertain

How much residual gap is acceptable?

Greater than 2 mm displacement on CT is the practical threshold for anatomical reduction.

Outcomes data (Choudhry/Crawford) suggest displacement under about 2.5 mm after sound reduction is tolerated; the safe upper limit is not defined.

Closed percutaneous versus open fixation for triplane?

The articular surface must be congruent however it is achieved.

Closed reduction with percutaneous screws gives good results when reduction is perfect, but the threshold to convert to open is judgement-based.

Is CT needed for every transitional fracture?

CT is standard for SH-III/IV, Tillaux and triplane planning.

Radiation stewardship versus information gain in clearly undisplaced patterns; some centres use limited-sequence MRI.

Should screws cross the physis?

Avoid crossing the physis where the geometry allows.

In transitional fractures the physis is closing, so a transphyseal screw is often acceptable; in young children it is avoided.

How long to follow for growth arrest?

Medial malleolus SH-III/IV and high-energy distal tibial injuries need prolonged surveillance.

Optimal frequency and total duration vary; at least 12 months is supported for medial malleolus injuries, longer with substantial growth remaining.

Body / Source

Emphasis

Practical Position

AO Foundation (Paediatric)

Mechanism, Salter-Harris pattern and physis-sparing fixation.

Anatomical reduction of intra-articular fragments; implants chosen to minimise physeal injury; CT for transitional patterns.

AAOS / POSNA literature (US)

Classification-driven management and growth-arrest risk.

Low threshold for CT in intra-articular and transitional fractures; surveillance for premature physeal closure.

BOA / BOAST (UK, paediatric trauma principles)

Timely senior-led care, neurovascular documentation and open-fracture pathways.

Soft-tissue and neurovascular assessment first; defined escalation for open or deformed injuries.

EFORT / European paediatric trauma consensus

Standardised physeal-injury assessment and follow-up.

Reduce the joint, protect the physis and follow to skeletal maturity in high-risk patterns.

Element

Well-resourced setting

Limited-resource setting

Imaging

CT routine for transitional and SH-III/IV fractures; MRI available for occult injury.

Reliance on good-quality mortise and lateral radiographs; intra-operative arthrogram or image intensifier to judge congruity.

Fixation

Cannulated screws and image intensifier readily available.

K-wires and careful closed reduction where screws are scarce; sound reduction still prioritised.

Follow-up

Structured growth-arrest surveillance to maturity.

Surveillance limited by access; clear safety-netting and return advice become essential.

Pattern	What It Is	Treatment Meaning
Tillaux	SH-III anterolateral distal tibial epiphyseal fragment avulsed by AITFL.	CT assesses step/gap; fixation usually if greater than 2 mm.
Two-part triplane	Epiphyseal and metaphyseal components connected in a multiplanar SH-IV pattern.	CT determines reduction and screw trajectory.
Three-part triplane	Separate epiphyseal, metaphyseal and medial/lateral components.	Often needs more detailed open or percutaneous fixation planning.
Intramalleolar/variant triplane	Less common multiplanar pattern involving the malleolar region.	Do not force it into a simple Tillaux label; CT defines the operation.

Mechanism	Use	Limitation
Supination-inversion	Common paediatric ankle injury mechanism.	Does not replace Salter-Harris or CT-based articular assessment.
Supination-external rotation	Helps predict distal tibial/fibular sequence.	Pattern can be altered by physeal closure stage.
Pronation-eversion / external rotation	Raises syndesmosis and transitional-pattern concern.	Needs radiographic and CT confirmation.

Pattern	Treatment	Follow-Up
Undisplaced distal fibula physeal injury	Below-knee cast or boot depending local practice and pain.	Clinical review; avoid overcalling sprain if physeal tenderness is present.
Stable extra-articular distal tibial physeal injury	Cast after acceptable alignment.	Repeat radiographs to ensure alignment is maintained.
Tillaux/triplane with less than 2 mm displacement	Cast or close follow-up when CT confirms congruity.	Monitor for displacement and symptoms.
Higher growth remaining	Counsel about growth arrest even if treated non-operatively.	Longer radiographic surveillance.

Pattern	Indication	Goal
Displaced SH-I/II	Unacceptable alignment, unstable reduction or tissue block.	Restore alignment and protect the physis.
SH-III/IV	Articular step/gap usually greater than 2 mm.	Anatomical joint reduction and stable fixation.
Tillaux	CT-confirmed displacement greater than 2 mm or incongruent mortise.	Reduce anterolateral epiphyseal fragment and fix without violating the joint.
Triplane	Displaced epiphyseal/articular component, complex fragments or failed closed reduction.	Reduce epiphysis first, then metaphyseal component if needed.
Medial malleolus	Displaced SH-III/IV or unstable fragment.	Exact reduction and bar surveillance.

Pattern	What It Is	Treatment Meaning
Tillaux	SH-III anterolateral distal tibial epiphyseal fragment avulsed by AITFL.	CT assesses step/gap; fixation usually if greater than 2 mm.
Two-part triplane	Epiphyseal and metaphyseal components connected in a multiplanar SH-IV pattern.	CT determines reduction and screw trajectory.
Three-part triplane	Separate epiphyseal, metaphyseal and medial/lateral components.	Often needs more detailed open or percutaneous fixation planning.
Intramalleolar/variant triplane	Less common multiplanar pattern involving the malleolar region.	Do not force it into a simple Tillaux label; CT defines the operation.