High-yield overview

Supine | Two Incisions | Skin Bridge of at Least 7 cm | Entire Plafond Access

SupinePositioning for both incisions

2 incisionsAnteromedial plus anterolateral

7 cmMinimum skin bridge between incisions

43-CAO/OTA complex pilon pattern

Critical Must-Knows

Supine positioning with the limb rotated as needed to bring each surface into the field
Two incisions - the anteromedial (Ruedi-Allgower) and the anterolateral (fourth ray) - joined by a skin bridge of at least 7 cm
Anteromedial protects the saphenous nerve and long saphenous vein; anterolateral protects the superficial peroneal nerve
Stage definitive ORIF with a spanning external fixator first, and delay until the soft tissues settle (positive wrinkle sign)
Gives access to the entire plafond - the medial malleolus, the central die-punch fragment, and the anterolateral (Chaput) fragment

When & Why

What it exposes. The combined anteromedial and anterolateral approaches to the distal tibia bring two extensile incisions together to expose the entire anterior tibial plafond for open reduction and internal fixation of complex, comminuted pilon fractures (AO/OTA 43-C). The anteromedial incision, placed between the tibialis anterior tendon and the medial malleolus, gives direct access to the medial malleolus, the medial plafond, and the centrally impacted (die-punch) fragment. The anterolateral incision, made in line with the fourth ray and lateral to the tibialis anterior tendon and the tibial crest, exposes the anterolateral plafond and the Chaput (Tillaux-Chaput) fragment. The two incisions share a broad, full-thickness anterior flap separated by a skin bridge of at least 7 cm. Why this approach matters. Complex pilon fractures frequently split the plafond into a medial fragment, one or more central impacted (die-punch) fragments, and an anterolateral Chaput fragment, each of which may need direct visualisation to be reduced anatomically. No single anterior incision reaches them all without an unacceptably large and devitalising wound. The combined two-incision strategy preserves the anteromedial Ruedi-Allgower exposure for the medial and central columns while adding an anterolateral window for the Chaput fragment, accepting that the price is a large anterior flap that demands meticulous soft-tissue staging and an adequate skin bridge. Primary indications. - Complex pilon fractures (AO/OTA 43-C) with simultaneous medial, central (die-punch), and anterolateral (Chaput) articular fragments

Fractures in which a single anterior incision cannot access all fragments needing direct reduction
Patterns with a large anterolateral Chaput fragment plus an independent medial articular split
Salvage or revision pilon surgery where wide extensile access is required Contraindications. - A compromised anterior soft-tissue envelope with fracture blisters or closed degloving over the planned flap (absolute until soft tissues recover)
Contaminated open wounds crossing the planned incisions (consider external fixation)
Low-energy, minimally displaced patterns amenable to a single incision or non-operative care
Medical unfitness for a prolonged staged reconstructive procedure

The three approach variants
Variant	Incision line	What it reaches
Anteromedial	Between tibialis anterior and the medial malleolus, protecting the TA sheath	Medial malleolus and central plafond
Anterolateral	In line with the fourth ray, lateral to tibialis anterior	Anterolateral plafond and Chaput fragment
Combined	Both incisions joined by a broad full-thickness anterior flap	Entire plafond in complex 43-C

Alternative and complementary approaches. - Single anterolateral (direct lateral) approach: preferred when anterolateral and central fragments dominate and the medial column is intact

Single anteromedial approach: for predominantly medial plafond injuries without an anterolateral fragment
Posterolateral approach: for posterior column fragments of the plafond
Posteromedial approach: for posteromedial fragments
Minimally invasive percutaneous plating: for lower-energy patterns or poor soft tissues

Skin Bridge and Anterior Flap

The two incisions share a single broad anterior flap over the distal tibia, whose blood supply depends on cutaneous perforators. Maintain a skin bridge of at least 7 cm between the incisions, raise the flap full-thickness straight down to bone in one layer, and never dissect in laminae. A narrow bridge or layered dissection necroses the flap and converts a fixable fracture into a catastrophe.

Saphenous Nerve and Vein

The saphenous nerve and long (great) saphenous vein run together in the subcutaneous tissue of the anteromedial distal leg, anterior to the medial malleolus. They are the structures at risk in the anteromedial incision. Identify and protect them; the vein is a useful landmark and should be preserved where possible, and nerve injury leaves a numb medial ankle and a possible neuroma.

Superficial Peroneal Nerve

The superficial peroneal nerve pierces the deep fascia in the distal third of the leg and crosses the anterolateral field, becoming subcutaneous roughly 5 to 7 cm above the ankle joint. It is the structure most at risk in the anterolateral incision. Identify it early, mobilise it gently with a vessel loop, and never place a self-retaining retractor on it.

Anterior Neurovascular Bundle

The anterior tibial artery and deep peroneal nerve run together between tibialis anterior and extensor hallucis longus. During the anterolateral deep dissection the entire extensor compartment, together with this bundle, is elevated subperiosteally and retracted medially. Staying strictly on bone protects the bundle; it must never be individually skeletonised.

Staged Soft-Tissue Timing

Pilon wounds heal poorly through swollen, blistered skin. Stage the surgery: apply a spanning external fixator across the ankle acutely, restore length and alignment, and plate the fibula; then perform definitive ORIF through the combined incisions only once the wrinkle sign is positive, typically 10 to 21 days after injury.

Reconstruction Cornerstone

The Chaput (Tillaux-Chaput) fragment anchors the anterior inferior tibiofibular ligament, while the medial malleolus and the reduced central fragments restore the joint line. The combined approach exists to give direct, in-line access to each of these so that the entire articular surface can be reconstructed anatomically.

Reserve the combined approach for the worst fractures

The combined approach is reserved for the most complex, comminuted pilon fractures where a single incision cannot reach every articular fragment. If the soft-tissue bridge would be inadequate to reach every fragment, stage the surgery or choose a single-incision strategy rather than risk flap necrosis.

The Exposure

Work down through the layers in two windows, protecting the superficial nerves at every step, raising a single full-thickness flap to bone in each, and moving between the incisions to reduce the medial, central and Chaput fragments.

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Image Needed: Clinical PhotoHigh Priority

Intra-operative photograph of the combined anteromedial and anterolateral approach to a complex pilon fracture: two curvilinear incisions over the distal tibia separated by a broad full-thickness anterior flap, with the tibialis anterior tendon sheath preserved between them, vessel loops protecting the saphenous nerve and vein medially and the superficial peroneal nerve laterally, and the reconstructed tibial plafond exposed across both windows.

Context: A verified image is being sourced for this exposure.

Pending image generation or sourcing

### Position and landmarks Supine on a radiolucent table. A bolster or sandbag under the ipsilateral hip helps position the limb, which is rotated as needed during the case: slight external rotation brings the anteromedial surface into the operative field, and internal rotation brings up the anterolateral surface. A small bump under the distal leg improves lateral fluoroscopic views. The entire limb, including the hip, is prepared and draped so that it can be manoeuvred freely. A thigh tourniquet is used; exsanguination is gentle or omitted when the soft tissues are badly injured. Pre-positioning checks: confirm a radiolucent table and that the C-arm arcs freely from the contralateral side for AP, mortise and lateral images; verify image-intensifier access before draping, because reduction and hardware are checked repeatedly through both windows; pad all bony prominences and check the contralateral leg; and document a baseline neurovascular examination of the saphenous, superficial peroneal and deep peroneal nerves. Palpable bony landmarks. - Tibial crest / anterior tibial border - the ridge separating the two incisions

Medial malleolus - the distal reference for the anteromedial incision
Chaput (Tillaux-Chaput) tubercle - the anterolateral prominence of the distal tibia, palpable just proximal to the joint line
Lateral malleolus - the distal reference towards which the anterolateral incision trends
Fourth metatarsal ray - the distal continuation of the line of the anterolateral incision Soft-tissue landmarks. - Tibialis anterior tendon - the central landmark; the anteromedial incision lies on its medial side and the anterolateral incision on its lateral side
Long saphenous vein - visible in the anteromedial subcutaneous tissue, running with the saphenous nerve just anterior to the medial malleolus
Superficial peroneal nerve - identified in the anterolateral subcutaneous layer once the skin is opened ### Incision planning The two incisions are marked together before any cut is made, with a deliberate skin bridge of at least 7 cm between them. - Anteromedial incision: a curvilinear incision placed just posterior to the tibialis anterior tendon, running along the anteromedial border of the distal tibia towards the medial malleolus. It respects the tibialis anterior tendon sheath and exposes the medial malleolus and medial plafond.
Anterolateral incision: a curvilinear incision in line with the fourth ray, lateral to the tibialis anterior tendon and the tibial crest, curving distally towards the sinus tarsi. A single full-thickness flap is raised straight down to bone in one layer for each incision. Dissecting in layers here strips the skin of its perforator blood supply and predisposes to necrosis.

Exposure sequence

Step 1Mark both incisions together

Before any cut, mark the anteromedial and anterolateral incisions with a skin bridge of at least 7 cm between them, using the tibialis anterior tendon as the central landmark.
Infiltrate the skin only; avoid deep infiltration that distorts the superficial nerves.

Step 2Anteromedial incision and superficial dissection

Make a curvilinear incision just posterior to the tibialis anterior tendon, along the anteromedial border of the distal tibia towards the medial malleolus.
In the subcutaneous layer, identify and protect the saphenous nerve and long saphenous vein, which run together anterior to the medial malleolus.
Raise a single full-thickness flap straight down to the periosteum of the tibia; respect and protect the tibialis anterior tendon sheath, retracting the tendon laterally.

Step 3Anterolateral incision and superficial dissection

Make the curvilinear incision in line with the fourth ray, lateral to the tibialis anterior tendon and the tibial crest.
As the subcutaneous layer is divided, identify the superficial peroneal nerve crossing the field from lateral to medial, becoming subcutaneous roughly 5 to 7 cm above the ankle joint.
Mobilise it gently, protect it with a vessel loop, and raise a single full-thickness flap straight down to bone.

Step 4Anteromedial deep dissection

Working in the interval between the tibialis anterior tendon and the medial malleolus, carry the dissection subperiosteally onto the anteromedial distal tibia.
An anteromedial arthrotomy just below and parallel to the joint line opens the ankle and allows direct visualisation of the medial malleolus, the medial plafond, and the centrally impacted die-punch fragments, which are elevated and reduced.

Step 5Anterolateral deep dissection

Incise the deep fascia lateral to the tibialis anterior tendon and elevate the extensor compartment off the anterolateral tibia in a subperiosteal plane.
The anterior neurovascular bundle (anterior tibial artery and deep peroneal nerve) is carried medially with the extensors; staying on bone protects it.
Continue subperiosteally to expose the anterolateral plafond and the Chaput tubercle, and perform a limited anterior arthrotomy to visualise the impacted anterolateral articular surface.

Step 6Articular reconstruction across both windows

Move between the two incisions to reduce the medial malleolus, the central die-punch fragments, and the Chaput fragment anatomically, using the intact structures as references.
Provisional K-wire fixation holds each fragment while the definitive implants are prepared.

The anterior flap is the most vulnerable part of this approach

The dominant complication of the combined approach is anterior flap necrosis. Protect it at every step: design the two incisions with a skin bridge of at least 7 cm, raise each window as a single full-thickness flap straight from skin to bone in one layer (never dissect in laminae), avoid undermining that devascularises perforators, release retractors regularly, keep the flap moist, and stage definitive fixation until the wrinkle sign is positive.

Subperiosteal discipline protects the bundle

The single most important deep-dissection principle in both windows is to stay subperiosteally on the tibia. The anterior tibial artery and deep peroneal nerve lie immediately deep to the extensor muscles; by keeping the elevator on bone and sweeping the entire extensor compartment - with the bundle - medially, the vessels and nerve are protected and never individually skeletonised.

Dangers & Extensions

Internervous planes of the two incisions. The combined approach uses two distinct intervals, each with its own neurovascular considerations. The anteromedial incision has no true internervous plane. It is a subperiosteal exposure developed in the interval between the tibialis anterior tendon (deep peroneal nerve) and the medial malleolus. Because both margins relate effectively to a single nerve territory and the dissection is straight down onto subcutaneous bone, there is no classical internervous plane. The tibialis anterior tendon sheath is protected and the tendon retracted laterally, while the subcutaneous saphenous nerve and long saphenous vein are protected medially. The anterolateral incision uses a true internervous plane, between two muscle groups supplied by different nerves: - Anterior (extensor) compartment - supplied by the deep peroneal nerve (tibialis anterior, extensor hallucis longus, extensor digitorum longus, peroneus tertius)

Lateral (peroneal) compartment - supplied by the superficial peroneal nerve (peroneus longus, peroneus brevis) This intercompartmental interval allows the anterolateral tibial surface to be reached without denervating muscle. To reach bone, the dissection is carried lateral to the tibialis anterior tendon, and the entire extensor compartment - together with the anterior neurovascular bundle (anterior tibial artery and deep peroneal nerve) - is elevated subperiosteally and retracted medially.

Muscle compartments and their innervation
Compartment	Muscle	Nerve Supply	Role in the Approach
Anterior (extensor)	Tibialis anterior	Deep peroneal nerve	Central landmark - anteromedial lies medial, anterolateral lies lateral to its tendon
Anterior (extensor)	Extensor hallucis longus	Deep peroneal nerve	Elevated medially with the NV bundle in the anterolateral window
Anterior (extensor)	Extensor digitorum longus	Deep peroneal nerve	Floor of the anterolateral interval - raised medially
Anterior (extensor)	Peroneus tertius	Deep peroneal nerve	Marks the transition to the peroneal compartment
Lateral (peroneal)	Peroneus longus	Superficial peroneal nerve	Retracted laterally in the anterolateral window
Lateral (peroneal)	Peroneus brevis	Superficial peroneal nerve	Retracted laterally with the peronei

Key neurovascular structures by incision
Structure	Incision	Course	Clinical Significance
Saphenous nerve	Anteromedial	Subcutaneous, anterior to the medial malleolus, with the long saphenous vein	At risk in the subcutaneous layer - injury causes medial ankle numbness and possible neuroma
Long saphenous vein	Anteromedial	Runs with the saphenous nerve anteromedially	Useful landmark and drainage - preserve where possible
Superficial peroneal nerve	Anterolateral	Pierces fascia distally and crosses the field 5 to 7 cm above the joint	Most at-risk structure in the anterolateral incision - dorsal foot numbness and weak eversion
Deep peroneal nerve	Anterolateral (deep)	Within the anterior NV bundle	Travels with the anterior tibial artery - first web space sensation and toe extension
Anterior tibial artery	Anterolateral (deep)	Between tibialis anterior and EHL, continues as dorsalis pedis	Bleeding risk - protected by subperiosteal elevation medially

Layer-by-layer danger structures
Layer	Incision	Structure at Risk	Protection Strategy
Subcutaneous	Anteromedial	Saphenous nerve and long saphenous vein	Identify early, protect with the flap, preserve the vein
Subcutaneous	Anterolateral	Superficial peroneal nerve	Identify early, vessel loop, no metal retractors
Flap	Both	Anterior flap vascularity	Full-thickness to bone, minimum 7 cm bridge, no layered dissection
Deep fascia	Both	Extensor tendons (TA, EHL, EDL, peroneus tertius)	Keep moist, protect paratenon, gentle retraction
Deep on tibia	Anterolateral	Anterior tibial artery and deep peroneal nerve	Stay subperiosteal, elevate medially with the extensors
Articular	Both	Anterior ankle cartilage and capsule	Careful capsulotomy, small retractors on bone

The Chaput fragment anchors the syndesmosis

The Chaput (Tillaux-Chaput) tubercle is the anterolateral distal tibial prominence that gives attachment to the anterior inferior tibiofibular ligament. In complex pilon fractures it is frequently split off as a separate fragment. Because the Chaput fragment anchors the syndesmotic ligament, its anatomic reduction restores both the articular surface and the distal tibiofibular relationship. The anterolateral window gives direct, in-line access to it, which is the principal reason the anterolateral incision is added to the anteromedial one.

Mnemonic

BRIDGEBRIDGE - protecting the anterior flap and skin bridge

Both incisions planned apart

Design the anteromedial and anterolateral incisions with an adequate bridge

Raise a full-thickness flap

Go straight from skin to bone in a single layer to preserve perforators

Interval of at least 7 cm

Keep a minimum skin bridge between the two incisions

Do not dissect in layers

Layered dissection strips the skin of its blood supply

Guard the perforator supply

Avoid undermining that devascularises the anterior flap

Examine flap viability throughout

Release retractors regularly and keep the flap moist

### Extension of each incision Anteromedial extension. Proximally, the incision extends along the anteromedial border of the tibia for fractures running into the distal diaphysis or to seat a longer medial plate. Distally, it curves around the medial malleolus to expose the medial ankle and deltoid ligament complex when required. Anterolateral extension. Proximally, it extends along the anterolateral tibial border in line with the tibial crest for longer anterolateral plates. Distally, it can be carried towards the sinus tarsi and the base of the fourth ray for combined ankle and hindfoot work; the superficial peroneal nerve becomes increasingly tethered distally and must be handled with care. Combined and staged options. When the anterior flap is judged too precarious for both incisions at once, the two windows are staged: the dominant incision is used first and the second is added days later once the flap has declared itself viable. For patterns with posterior column involvement, a posterolateral or posteromedial incision can be added through a separate, well-spaced skin bridge, and the limb repositioned between anterior and posterior work.

Procedures Through This Approach

Complex pilon fracture ORIF with medial, central and anterolateral articular fragments
Reduction of the medial malleolus and medial plafond through the anteromedial window
Elevation of the central die-punch fragment with metaphyseal bone grafting
Reduction of the Chaput (Tillaux-Chaput) fragment and restoration of the syndesmosis through the anterolateral window
Medial and anterolateral buttress or periarticular plating of the reconstructed columns
Anterior ankle arthrotomy, loose-body removal, or debridement ### Staged, soft-tissue-respecting management Stage 1 (acute, day 0 to 2). A spanning external fixator across the ankle restores length, alignment and rotation through ligamentotaxis, and fibular plating is performed if the fibula is fractured. This re-establishes the soft-tissue envelope, maintains length, and buys time. A CT is obtained after the frame to plan fragment-specific fixation. Stage 2 (definitive, day 10 to 21). Once the wrinkle sign is positive, fracture blisters have re-epithelialised, and swelling has subsided, definitive ORIF is performed through the combined incisions. ### Reduction and fixation principles 1. Restore fibular length and alignment (usually at Stage 1)

Reconstruct the articular surface, using the medial malleolus and the Chaput fragment as references, and elevate the impacted central fragments
Bone graft the metaphyseal void after articular elevation
Apply buttress or periarticular plates to the medial and anterolateral columns, contoured to the distal tibia
Confirm reduction and hardware on AP, mortise and lateral fluoroscopy, aiming for an articular step-off of less than 2 mm

Mnemonic

FABBFABB - the Ruedi-Allgower four principles of pilon reconstruction

Fibular length restored

Fix the fibula first to restore length and the lateral column

Articular surface reconstructed

Reduce the plafond anatomically, using the medial malleolus and Chaput fragment as references

Bone graft the defect

Fill the metaphyseal void left after elevating the impacted central fragments

Buttress plating of the columns

Support the reconstructed medial and anterolateral columns with buttress plates

Viva & Exam Focus

Mnemonic

COMBINEDCOMBINED - the operative sequence

CT-plan every fragment

Map the medial, central die-punch and Chaput fragments before incising

One stage is spanning external fixation

Restore length and alignment, plate the fibula, and let soft tissues recover

Mark both incisions with a 7 cm bridge

Anteromedial between tibialis anterior and the medial malleolus; anterolateral over the fourth ray

Bump and position supine

Rotate the limb as needed to bring each surface into the field

Identify and protect each nerve

Saphenous nerve and vein medially; superficial peroneal nerve laterally

Navigate medial and central fragments

Use the anteromedial arthrotomy to reduce the medial malleolus and central die-punch

Expose the anterolateral plafond

Work lateral to tibialis anterior to reach the Chaput fragment

Definitive fixation and grafting

Bone-graft the metaphyseal void and apply buttress plates to each column

Clinical Decision Scenarios

Practise clinical reasoning and management decisions out loud

Viva scenarioStandard

Clinical prompt

“A 42-year-old man is injured in a motor vehicle collision and sustains a closed AO/OTA 43-C pilon fracture. CT shows a split medial malleolus, an impacted central die-punch fragment, and a separate anterolateral Chaput fragment, with an associated fibular fracture. The leg is markedly swollen but the skin is intact. Describe your surgical approach and how you would expose and reduce this fracture.”

Practical approach

**Initial management:** A full ATLS workup for associated injuries, and a detailed neurovascular and soft-tissue examination paying particular attention to the saphenous, superficial peroneal and deep peroneal nerve territories. Radiographs (AP, lateral, mortise) and a CT scan define the medial malleolus, the central die-punch fragment and the Chaput fragment, and confirm that no single incision can reach them all. **Staged philosophy:** Because this is a high-energy injury with a swollen anterior soft-tissue envelope, I would manage it in two stages. Stage one is an acute spanning external fixator across the ankle with restoration of length, alignment and rotation, and plating of the fibula to restore the lateral column. I would wait for the soft-tissue envelope to recover - a positive wrinkle sign and re-epithelialisation of any blisters, typically 10 to 21 days - before definitive fixation, and obtain a CT after the frame to plan fragment-specific reduction. **Definitive approach:** I would use the combined anteromedial and anterolateral approaches. The patient is positioned supine. I mark both incisions together with a skin bridge of at least 7 cm, using the tibialis anterior tendon as the central landmark. The anteromedial incision lies between the tibialis anterior tendon and the medial malleolus, protecting the tendon sheath, the saphenous nerve and the long saphenous vein; the anterolateral incision lies in line with the fourth ray, lateral to the tibialis anterior tendon, protecting the superficial peroneal nerve. Each window is raised as a single full-thickness flap to bone. **Reduction and fixation:** Through the anteromedial window I reduce the medial malleolus and elevate the central die-punch fragment. Through the anterolateral window, working lateral to tibialis anterior and elevating the extensor compartment and the anterior neurovascular bundle medially, I expose and reduce the Chaput fragment, which anchors the anterior inferior tibiofibular ligament and so restores the syndesmosis. I bone-graft the metaphyseal void and apply buttress plates to the medial and anterolateral columns. I confirm reduction and hardware on AP, mortise and lateral fluoroscopy, aiming for an articular step-off of less than 2 mm, and close over a splint with the ankle in neutral.

Key clinical points

Stage the surgery: spanning ex-fix and fibular fixation first, then delayed ORIF

Two incisions with a skin bridge of at least 7 cm, raised as full-thickness flaps

Anteromedial window protects the saphenous nerve and long saphenous vein

Anterolateral window protects the superficial peroneal nerve

Medial malleolus and central die-punch reduced anteromedially; Chaput fragment reduced anterolaterally

Anterolateral internervous plane between the extensor and peroneal compartments

Buttress plates to the medial and anterolateral columns; bone-graft the void

Target articular step-off of less than 2 mm

Common pitfalls

Operating through swollen, blistered skin without staging

Placing the two incisions too close together and necrosing the anterior flap

Not identifying and protecting the saphenous and superficial peroneal nerves

Forgetting that the Chaput fragment carries the anterior inferior tibiofibular ligament

Further questions

“How would you manage an open pilon fracture with this pattern, and what is the significance of the wrinkle sign?”

Viva scenarioChallenging

Clinical prompt

“Ten days after combined anteromedial and anterolateral ORIF of a pilon fracture, the skin bridge between the two incisions becomes dusky and then breaks down, with a small area of exposed plate. How do you assess and manage this?”

Practical approach

**Immediate assessment:** I examine the wound and the whole anterior flap, looking for the extent of necrosis, the presence of frank purulence, and any exposed hardware or joint. I assess the systemic inflammatory response and the neurovascular status of the foot, and I review the operative note and the intra-operative photographs for the design of the flap and the skin bridge. **Investigation:** I obtain inflammatory markers and a plain radiograph to check for hardware stability and early sign of joint involvement. If there is any suspicion of deep infection I obtain a CT or MRI to look for a deep collection or osteomyelitis, and I involve the microbiology and plastic surgery teams early. **Most likely diagnosis:** Anterior flap marginal necrosis with possible superficial or deep wound breakdown - the dominant soft-tissue complication of the combined approach, driven by an inadequate skin bridge, a layered rather than full-thickness flap, swelling, or operating before the wrinkle sign was positive. **Management principles:** If the necrosis is superficial and dry with no exposed hardware or joint, I manage it conservatively with local wound care, surveillance and antibiotics only if clinically infected. If there is exposed plate or joint, or a deep infection, I take the patient to theatre for surgical debridement, send deep samples for culture, and remove non-essential hardware while retaining fixation where possible. Once the wound is clean I cover it with a plastic surgical flap - typically a fasciocutaneous or free flap - in collaboration with the plastic surgeon, and I splint the ankle and elevate the limb. **Prevention review:** I would review the case to confirm the flap was raised full-thickness with a skin bridge of at least 7 cm and that the surgery was staged until the wrinkle sign was positive, and consider an incisional negative-pressure dressing for future high-risk flaps.

Key clinical points

Anterior flap necrosis is the dominant complication of the combined approach

Assess the extent of necrosis, exposed hardware, joint involvement and deep infection

Involve microbiology and plastic surgery early

Superficial dry necrosis can be managed conservatively with wound care

Exposed plate, joint or deep infection needs surgical debridement and targeted antibiotics

Clean soft-tissue cover typically needs a fasciocutaneous or free flap

Prevention: full-thickness flap, 7 cm bridge, staging, and incisional NPWT

Common pitfalls

Assuming superficial breakdown cannot mask deep infection

Delaying debridement when hardware or joint is exposed

Removing all fixation and losing the reduction before cover is secured

Not involving plastic surgery early enough for definitive cover

Further questions

“What flap options are available for cover of the distal tibia, and when would you remove versus retain hardware in an infected pilon?”

Viva scenarioStandard

Clinical prompt

“Compare the single anterolateral approach with the combined anteromedial and anterolateral approaches for a pilon fracture. When would you choose each?”

Practical approach

**Single anterolateral approach:** The incision runs in line with the fourth ray, lateral to the tibialis anterior tendon and the tibial crest, exposing the anterolateral plafond and the Chaput fragment. The internervous plane lies between the extensor compartment (deep peroneal nerve) and the peroneal compartment (superficial peroneal nerve), with the extensor compartment and the anterior neurovascular bundle elevated medially. It is chosen for anterolateral and central split-depression patterns, when anterolateral plating is planned, and because it preserves the anteromedial soft tissues. Its key danger is the superficial peroneal nerve. **Combined anteromedial and anterolateral approach:** This adds an anteromedial incision between the tibialis anterior tendon and the medial malleolus, protecting the tendon sheath, the saphenous nerve and the long saphenous vein, to reach the medial malleolus, the medial plafond and the central die-punch fragment. The two incisions share a broad anterior flap separated by a skin bridge of at least 7 cm. It is chosen for the most complex, comminuted patterns in which a single incision cannot reach the medial, central and Chaput fragments simultaneously. Its price is a larger, more vulnerable anterior flap and a higher wound-complication risk. **Choice:** I use the single anterolateral approach for anterolateral or central patterns and whenever the medial column is intact, because it is more soft-tissue-friendly. I reserve the combined approach for complex 43-C fractures with a medial articular split, a central die-punch fragment and an anterolateral Chaput fragment that all need direct visualisation, accepting the added flap risk in exchange for complete articular access. Whichever is chosen, the goal is an anatomic articular reduction, restoration of length and column alignment, and a stable construct that respects the soft tissues - usually achieved by staging.

Key clinical points

Single anterolateral: in line with the fourth ray, lateral to tibialis anterior

Single anterolateral is more soft-tissue-friendly and suits anterolateral or central patterns

Combined approach adds an anteromedial window for the medial malleolus and central die-punch

Combined approach needs a skin bridge of at least 7 cm and a full-thickness anterior flap

Anteromedial dangers: saphenous nerve and long saphenous vein

Anterolateral danger: superficial peroneal nerve

Reserve the combined approach for complex patterns needing access to all fragments

Both are staged to respect the soft tissues

Common pitfalls

Choosing a combined approach when a single incision would suffice

Placing the two incisions too close together

Confusing which nerve is at risk in each incision

Forgetting that the combined anterior flap carries a higher wound-complication risk

Further questions

“What internervous plane does the anterolateral component use, and how do you maintain anterior flap vascularity in the combined approach?”

Exam day cheat sheet

COMBINED ANTEROMEDIAL AND ANTEROLATERAL APPROACHES TO THE PILON

Position & Incisions

Supine on a radiolucent table; rotate the limb between external (anteromedial) and internal (anterolateral) rotation
C-arm from the contralateral side for AP, mortise and lateral views
Anteromedial incision between tibialis anterior and the medial malleolus, protecting the tendon sheath
Anterolateral incision in line with the fourth ray, lateral to the tibialis anterior tendon and crest
Skin bridge of at least 7 cm; each window raised as a full-thickness flap to bone

Internervous Plane

Anteromedial: no true internervous plane - subperiosteal interval between tibialis anterior and the medial malleolus
Anterolateral: extensor compartment (deep peroneal nerve) and peroneal compartment (superficial peroneal nerve)
Operative interval lateral to tibialis anterior for the anterolateral window
Extensor compartment and anterior NV bundle elevated subperiosteally and retracted medially
Stay on bone to protect the anterior tibial artery and deep peroneal nerve

Structures at Risk

Anterior flap vascularity - the dominant risk; full-thickness flap and at least 7 cm bridge
Saphenous nerve and long saphenous vein in the anteromedial subcutaneous layer
Superficial peroneal nerve crossing the anterolateral field 5 to 7 cm above the joint
Anterior tibial artery and deep peroneal nerve in the deep anterolateral dissection
Extensor tendons (TA, EHL, EDL, peroneus tertius) - keep moist and protect paratenon

What You Expose

Medial malleolus and medial plafond through the anteromedial window
Central impacted (die-punch) fragment via the anteromedial arthrotomy
Anterolateral plafond and Chaput (Tillaux-Chaput) fragment through the anterolateral window
The entire anterior plafond and anterior ankle capsule
Bone for contoured medial and anterolateral buttress plates

Extension & Procedures

Anteromedial extends proximally along the tibia and distally around the medial malleolus
Anterolateral extends proximally along the tibial border and distally toward the sinus tarsi
Complex pilon ORIF with medial, central and anterolateral fragments
Chaput fragment reduction and syndesmotic restoration
Medial and anterolateral buttress plating with metaphyseal bone grafting

Closure & Staged Care

Layered closure; do not force a tight fascial closure in swollen tissue
Splint the ankle in neutral; consider incisional NPWT over the anterior flap
Stage definitive ORIF until the wrinkle sign is positive (10 to 21 days)
Restore fibular length, reconstruct the articular surface, bone graft the void, buttress-plate both columns
Target an articular step-off of less than 2 mm

References

Guidelines, Registries & Global Practice Pilon fractures are high-energy intra-articular injuries managed at trauma centres worldwide. Across examination systems, practice converges on CT-based pre-operative planning, soft-tissue-respecting staged management, anatomic articular reconstruction, and column-specific buttress plating. The combined anteromedial and anterolateral approach is reserved for the most comminuted patterns in which a single anterior incision cannot reach the medial, central and anterolateral (Chaput) fragments simultaneously, and it is always performed against a background of staged soft-tissue care. Side-by-side principles (where guidance converges): | Body | Position on pilon fractures |

|------|------------------------------| | AO Foundation | CT mandatory for articular fractures; staged management with spanning external fixation for high-energy injuries with soft-tissue compromise; column and fragment-specific fixation and buttress plating | | BOA / BOAST (open and soft-tissue) | Early soft-tissue assessment and photographic documentation; joint orthoplastic care for open injuries; definitive fixation only once the soft tissues permit | | OTA / AAOS | Anatomic articular reduction and restoration of length, alignment and rotation as primary goals; CT-based planning as standard of care | Global practice variation: In high-resource settings, pre-contoured periarticular plates, dedicated pilon implants, routine CT and incisional negative-pressure dressings are standard, and a combined approach is used selectively for the most complex patterns. In resource-limited settings, the same biomechanical principles are achieved with spanning or definitive external fixation and with contoured small-fragment plates, and external fixation carries a larger role in definitive management, with the combined extensile exposure used more sparingly because of its soft-tissue demands. Consent (globally applicable): discuss anterior flap necrosis and wound breakdown with possible need for plastic surgical cover (the dominant complications, reduced but not abolished by staging), superficial and deep infection, saphenous and superficial peroneal nerve injury, stiffness, post-traumatic arthritis, and the possible need for future ankle arthrodesis if the articular damage is severe.

Orthopaedic relevance for the operative station

Be able to describe the combined approach systematically: supine positioning, the two incisions with a skin bridge of at least 7 cm and full-thickness flaps, protection of the saphenous nerve and long saphenous vein anteromedially and the superficial peroneal nerve anterolaterally, the anterolateral internervous plane between the deep and superficial peroneal nerve territories, subperiosteal medial elevation of the extensor compartment and anterior bundle, direct access to the medial malleolus, central die-punch and Chaput fragments, medial and anterolateral buttress plating, and a staged, soft-tissue-respecting closure.

Evidence

Fractures of the Lower End of the Tibia Into the Ankle Joint: Results 9 Years After Open Reduction and Internal Fixation

Ruedi TP, Allgower M • Clinical Orthopaedics and Related Research (1979)

Key Findings:

Established the four foundational principles of pilon reconstruction
Restore fibular length and anatomy first
Reconstruct the articular surface of the tibial plafond
Bone graft the metaphyseal defect and apply buttress plating to support the reconstructed column

Evidence

Two-Staged Delayed Open Reduction and Internal Fixation of Severe Pilon Fractures

Patterson MJ, Cole JD • Journal of Orthopaedic Trauma (1999)

Key Findings:

Introduced a two-stage protocol for severe (AO/OTA 43-C) pilon fractures
Stage one used immediate spanning external fixation with fibular plating; stage two was delayed open reduction and internal fixation
Staging allowed the soft-tissue envelope to recover before definitive exposure
Reported a marked reduction in wound complications compared with single-stage management

Evidence

A Staged Protocol for Soft Tissue Management in the Treatment of Complex Pilon Fractures

Sirkin M, Sanders R, DiPasquale T, Herscovici D Jr • Journal of Orthopaedic Trauma (1999)

Key Findings:

Applied a staged protocol of immediate spanning external fixation followed by delayed definitive fixation to complex pilon fractures
Delayed definitive internal fixation until the soft tissues had recovered
Reported a low rate of deep infection when definitive fixation was timed to soft-tissue recovery
Established the condition of the soft-tissue envelope as the determinant of the timing of definitive fixation

Evidence

Anatomy of Pilon Fractures of the Distal Tibia

Topliss CJ, Jackson M, Atkins RM • Journal of Bone and Joint Surgery British Volume (2005)

Key Findings:

Mapped the standard articular fragments of pilon fractures from CT, including the anterolateral, posterolateral, medial and central fragments
Showed that complex pilon fractures consistently split into recognisable fragments across the entire plafond
Provided the anatomic basis for choosing incisions that give direct access to each fragment
Supported combined anterior approaches when medial, central and anterolateral fragments all require direct visualisation

Evidence

A Prospective Study Evaluating Incision Placement and Wound Healing for Tibial Plafond Fractures

Howard JL, Agel J, Barei DP, Benirschke SK, Nork SE • Journal of Orthopaedic Trauma (2008)

Key Findings:

Prospectively evaluated incision placement and wound healing in operatively treated tibial plafond fractures
Examined the anterolateral approach and the relationship of incision design to soft-tissue healing
Informed the importance of an adequate skin bridge and full-thickness flap design around the distal tibia
Reinforced soft-tissue-respecting incision planning as central to reducing wound complications