Tibiofibular Syndesmosis

1. High-Yield Summary

• Primary Clinical Indication: Acute or subacute unstable distal tibiofibular syndesmotic disruption occurring in association with rotational ankle fractures (Danis-Weber Type C, Lauge-Hansen pronation-external rotation [PER-III and PER-IV], Maisonneuve fracture variants) or high-grade pure ligamentous high ankle sprains exhibiting dynamic or static diastasis.
• Biomechanical Imperative: The syndesmosis maintains stability of the amphiarthrodial mortise; cadaveric biomechanical data confirm that even 1 mm of lateral talar displacement decreases the tibiotalar contact area by greater than 40%, generating abnormal peak contact stresses that accelerate post-traumatic osteoarthritis.
• Critical Move: Direct visual clearing of interposed ligamentous shreds and fibrocartilage from the tibial incisura fibularis through an anterior mini-arthrotomy, followed by anatomical reduction under direct visual and tactile control prior to clamp application, placing clamp tines along the true 20-to-30-degree anterior-to-posterior incisural axis.
• Fixation Paradigm: Level I randomized controlled trials establish that dynamic suture-button fixation provides physiologic micromotion, lowers the rate of computed tomography (CT)-documented malreduction, yields superior patient-reported functional outcome scores, and avoids routine secondary implant removal compared to rigid syndesmotic screws.
• Catastrophic Technical Error: Clamp-induced sagittal and rotational malreduction (typically posterior translation and internal rotation of the distal fibula) caused by placing reduction clamp tines in a pure transverse coronal vector or applying excessive clamp compression.

2. Indications

Operative stabilization of the distal tibiofibular syndesmosis is governed by objective clinical, functional, and radiographic indicators of mechanical instability within the ankle mortise:

Absolute Indications:

• Frank syndesmotic diastasis demonstrated on non-stress or stress radiographs (tibiofibular clear space >= 6 mm, tibiofibular overlap < 1 mm on mortise projection, or medial clear space widening > 4 mm).
• Intraoperative syndesmotic instability verified under live fluoroscopic stress testing (Cotton bone hook traction test or external rotation stress test demonstrating >= 2 mm widening of the tibiofibular or medial clear space) following definitive rigid osteosynthesis of associated lateral malleolar or posterior malleolar fractures.
• High-energy ankle fracture patterns with syndesmotic incompetence proximal to the plafond: Danis-Weber Type C fractures, Lauge-Hansen PER-III and PER-IV injuries, and Maisonneuve fractures (proximal fibular neck fractures associated with complete disruption of the crural interosseous membrane and syndesmotic ligaments).
• Unstable pure ligamentous syndesmotic disruptions (simultaneous complete tears of the anterior-inferior tibiofibular ligament [AITFL], interosseous ligament [IOL], posterior-inferior tibiofibular ligament [PITFL], and deep deltoid ligament complex) without fibular fracture.

Relative Indications:

• Latent syndesmotic instability in elite athletic populations (West Point Grade IIb high ankle sprains) presenting with dynamic widening, persistent weight-bearing pain, and cross-sectional magnetic resonance imaging (MRI) demonstrating full-thickness AITFL and IOL disruption.
• Danis-Weber Type B (supination-external rotation [SER-IV]) fractures where persistent tibiofibular widening is confirmed on intraoperative stress testing following anatomical lag screw and neutralisation plate fixation of the lateral malleolus.
• Small posterior malleolar avulsion fractures (< 20% articular surface involvement) treated non-operatively where dynamic syndesmotic instability persists under manual hook testing.

Contraindications:

• Absolute: Active superficial or deep infection, soft-tissue cellulitis, or purulent draining wounds over the lateral or medial malleolar surgical corridors; severe peripheral vascular disease with non-reconstructable distal limb ischemia; severe systemic medical compromise precluding operative intervention.
• Relative: Severe acute soft-tissue envelope compromise, hemorrhagic fracture blisters, or extensive open degloving injuries (requires damage-control temporary external fixation until skin wrinkling and epithelial re-epithelialization appear); chronic neglected syndesmotic diastasis (> 3 to 6 months) characterized by fibrous union or incisural remodeling, which necessitates open reconstructive debridement, corrective osteotomy, or syndesmotic arthrodesis rather than primary flexible stabilization.

3. Preoperative Planning

Imaging Review

Meticulous multiplanar radiographic and cross-sectional imaging evaluation is mandatory prior to operative intervention:

• Standard Radiographic Series: Weight-bearing or non-weight-bearing anteroposterior (AP), mortise (15 to 20 degrees internal rotation), and lateral radiographs of the ankle. Full-length tibia and fibula AP and lateral views must be obtained routinely to exclude a proximal Maisonneuve fibular neck fracture whenever isolated medial clear space widening or syndesmotic widening is detected.
• Tibiofibular Clear Space (TFCS): Measured on AP and mortise projections 1 cm proximal to the tibial plafond between the posterior rim of the anterior tibial tubercle (Chaput) and the medial cortex of the distal fibular shaft. Normal threshold is strictly < 6 mm. This parameter is the most reliable plain radiographic marker because it remains relatively unaffected by rotational variations of the ankle.
• Tibiofibular Overlap (TFO): Measured 1 cm proximal to the tibial plafond. Normal overlap is > 6 mm on the AP projection and > 1 mm on the 15-to-20-degree mortise view. A loss of overlap indicates transverse syndesmotic diastasis.
• Medial Clear Space (MCS): Measured on the mortise view between the lateral aspect of the medial malleolus and the medial border of the talus. Normal is <= 4 mm and must be equal to or less than the superior clear space. An MCS > 4 mm confirms rupture or incompetence of the deep deltoid ligament complex.
• Axial Computed Tomography (CT) / Weight-Bearing CT (WBCT): Axial slices evaluated 1 cm proximal to the tibial plafond provide the gold standard assessment of rotational and sagittal fibular alignment within the concave tibial incisura. CT readily identifies subtle rotational malreduction, posterior translation, and intra-articular bony avulsion fragments (Chaput, Wagstaffe, or Volkmann) that impede anatomical closed reduction.
• Magnetic Resonance Imaging (MRI): Reserved for suspected latent or occult syndesmotic disruptions in high-performance athletes, delineating complete versus partial tears of the AITFL, PITFL, and interosseous ligament while evaluating concomitant osteochondral lesions of the talus (OLT).

Equipment Checklist

The operative suite must be equipped with specialized instrumentation and implants prior to induction:

• High-definition digital C-arm fluoroscopy unit with unobstructed arc rotation.
• Pointed bone reduction forceps (large Weber reduction clamp and small pointed reduction clamp) with hardened tungsten points.
• Bone hook for performing the intraoperative Cotton traction test.
• Specialized exposure tools: curved and angled dental picks, Freer elevator, small angled curettes, and fine Luer rongeurs for clearing fibrocartilage from the incisura fibularis.
• Retractors: mini-Hohmann retractors, small blunt Senn retractors, and Langenbeck retractors.
• Smooth Kirschner wires (1.6 mm and 2.0 mm) for provisional stabilization.
• Dynamic Suture-Button Set: Tensionable continuous-loop high-strength ultra-high molecular weight polyethylene (UHMWPE) suture construct with titanium or polyetheretherketone (PEEK) oblong medial and round lateral buttons, long guideneedle, calibrated cannulated drill bits (3.2 mm or 3.7 mm), and tensioning handles.
• Cortical Screw Set: 3.5 mm and 4.5 mm fully threaded solid and cannulated cortical screws, corresponding calibrated drill bits (2.5 mm, 2.7 mm, 3.2 mm), countersink, calibrated depth gauge, and matching washers.

Examination Under Anesthesia (EUA)

Following induction of anesthesia and immediately following any required lateral malleolar or medial osteosynthesis, dynamic stability of the syndesmosis must be confirmed under live fluoroscopy:

• Cotton (Bone Hook) Test: A sterile bone hook or pointed reduction clamp is placed around the distal fibular shaft 2 to 3 cm proximal to the ankle joint line. While the distal tibia is held stationary, a direct lateral and posterolateral traction force is applied to the fibula under live mortise fluoroscopic visualization. More than 2 mm of lateral or posterolateral translation of the fibular shaft relative to the tibial incisura confirms syndesmotic incompetence.
• External Rotation Stress Test (Kleiger Test under Fluoroscopy): With the knee flexed to 90 degrees and the ankle held in neutral 90-degree dorsiflexion, an external rotation torque is applied to the hindfoot. Live fluoroscopy of the mortise is inspected; dynamic widening of the medial clear space (> 4 mm) or tibiofibular clear space (> 5 mm) establishes instability.
• Sagittal Translation (Drawer) Test: Manual anterior and posterior translation of the distal fibula within the incisura to detect subtle sagittal toggle, which frequently persists even when coronal radiographs appear deceptive.

4. Patient Positioning & Setup

Proper operating room layout, limb support, and fluoroscopic clearance are essential to prevent technical compromise during reduction:

• Patient Orientation: The patient is positioned supine on a fully radiolucent carbon-fiber operating table.
• Pelvic Bump: A folded sheet or silicone gel bump is placed beneath the ipsilateral buttock and pelvis. This counters the natural external rotation of the lower limb, maintaining the patella, tibial tuberosity, and second ray pointing strictly perpendicular toward the ceiling for reproducible mortise orientation.
• Limb Elevation: A padded sterile foam ramp or rolled towel support is placed under the distal calf and Achilles tendon, elevating the heel 10 to 15 cm off the tabletop. This allows unhindered 360-degree rotation of the C-arm for unobstructed lateral fluoroscopy without bed interference.
• Contralateral Limb Protection: The non-operative lower extremity is cushioned at all pressure points (peroneal nerve at the fibular neck, heel pad, and sacrum) and secured with a padded safety strap.
• Tourniquet Placement: A well-padded pneumatic tourniquet is applied to the proximal thigh over protective cast padding. The limb is exsanguinated with an Esmarch bandage before inflation to 250 mmHg (or 100 to 150 mmHg above systolic arterial pressure).

Safety Check

Prior to skin preparation and draping, the surgical team executes an essential fluoroscopic clearance verification:

• Rotate the C-arm between true AP, mortise (15 to 20 degrees internal beam tilt), and strict lateral projections (perfect superimposition of the medial and lateral talar domes and distal tibial plafond arc). Confirm that all three views can be captured rapidly without repositioning the patient or colliding with surgical drapes.
• Identify the anatomic transmalleolar incisural axis: because the tibial incisura faces approximately 20 to 30 degrees anteriorly relative to the coronal plane, verify that the fluoroscopic monitor is oriented directly across from the operating surgeon for immediate visual feedback.
• Verify tourniquet calibration, set an automated audible countdown timer for 90 minutes, and ensure the medial tibial corridor is draped widely to accommodate medial counter-incisions.

5. Approach

Surgical exposure requires an anterolateral approach to directly inspect and debride the incisura fibularis, combined with a medial counter-incision to safeguard medial neurovascular structures during implant deployment:

Anterolateral Trans-Fibular Approach:

• Incision: A 5-to-7 cm straight longitudinal incision is placed 1 cm anterior to the anterior border of the distal fibula, extending distally to within 1 cm of the lateral malleolar tip. When a lateral malleolar fracture is present, the standard lateral approach is extended anteriorly to expose the syndesmotic interval.
• Internervous Plane: Dissection proceeds through the internervous interval between the peroneus brevis laterally (innervated by the superficial peroneal nerve) and the peroneus tertius and extensor digitorum longus medially (innervated by the deep peroneal nerve).
• Superficial Peroneal Nerve (SPN) Danger Zone: The SPN pierces the crural fascia from the lateral compartment approximately 8 to 12 cm proximal to the tip of the lateral malleolus, arborizing into the medial and intermediate dorsal cutaneous nerves. Subcutaneous dissection must be performed bluntly without extensive subcutaneous flap undermining to prevent cutaneous neuroma formation.
• Deep Neurovascular Danger Zone: The anterior tibial artery and deep peroneal nerve traverse beneath the inferior extensor retinaculum along the anterior joint capsule. Maintenance of subperiosteal exposure across the anterior incisura rim and keeping retractors firmly against bone avoids neurovascular traction or direct laceration.

Medial Mini-Open Counter-Incision:

• Incision: A 1.5-to-2.0 cm longitudinal incision is centered directly over the subcutaneous medial face of the tibia, 2 to 3 cm proximal to the medial malleolar articular margin, in direct alignment with the planned implant exit path.
• Saphenous Danger Zone: The great saphenous vein and saphenous nerve cross directly over the anterior portion of the medial malleolus. Blunt dissection using a small curved hemostat down to the periosteum allows visualization and gentle anterior retraction of the saphenous bundle with a blunt Senn retractor, protecting them during drill passage and medial button seating.

6. Technique

Step 1: Exposure and Incisura Clearing

Achieving an anatomical reduction requires complete clearance of all interposed soft tissue from within the syndesmotic articulation:

• Incise the crural fascia longitudinally immediately anterior to the fibula, elevating full-thickness anterior soft-tissue flaps down to the syndesmotic interval.
• Retract the anterior tissues with a small Hohmann retractor seated over the anterior tibial tubercle (Chaput tubercle).
• Expose the anterior syndesmosis. Torn, frayed fibers of the AITFL are frequently trapped within the incisura fibularis, preventing concentric bone-on-bone seating.
• Debride the incisura meticulously. Use an angled dental pick, small curette, and fine rongeur to excise all hematoma, fibrocartilaginous scar tissue, and inverted ligamentous stumps from the anterior and central floor of the incisura.
• Preserve the subchondral bone and intact hyaline cartilage of the incisura and tibial plafond; debridement must target soft tissue debris without denuding healthy cortical boundaries.

Step 2: Anatomical Reduction

Reduction must be executed under direct visual and tactile inspection to avoid clamp-induced deformity:

• Mobilize the distal fibula manually with thumb pressure or a small bone hook, restoring proper length and correcting any internal or external rotational malalignment.
• Direct Visual Inspection: Align the anterior fibular tubercle (Wagstaffe-Le Fort) with the anterior tibial tubercle (Chaput). The anterior cortex of the fibula must form a smooth, contiguous curve with the anterior tibial cortex, sitting flush or recessed by no more than 1 to 2 mm within the incisural rim.
• Palpate the anterior and posterior boundaries of the incisura with a Freer elevator to ensure the fibular shaft sits centered within the concavity without rotational tilt.
• Apply a large pointed Weber reduction clamp. The lateral clamp tine is placed on the lateral fibular ridge (or through an open plate hole). The medial clamp tine must be placed on the anterior third of the medial tibial cortex, NOT in the midline or posterior third.
• Angle the clamp tines 20 to 30 degrees anteriorly to match the natural anatomical incisura axis. Tighten the clamp with finger-tight pressure only to hold the reduction. Never use the clamp to compress or force an unreduced fibula into place.

Step 3: Provisional Fixation and Fluoroscopic Assessment

Provisional stabilization allows immediate multiplanar fluoroscopic confirmation prior to definitive implant passage:

• Drive a 1.6 mm smooth Kirschner wire from lateral to medial across the fibula into the tibia, placed 2.5 to 3.0 cm proximal to the plafond and parallel to the planned implant trajectory.
• Release clamp tension once the K-wire is seated. Leaving excessive clamp compression during imaging obscures subtle overcompression or rotational deformities.
• Multiplanar Fluoroscopic Check (Mortise View): Confirm normal tibiofibular clear space (< 6 mm), tibiofibular overlap (> 1 mm), medial clear space (<= 4 mm, symmetric with superior joint line), an unbroken Shenton’s line of the ankle, and a continuous dime sign at the lateral talocrural angle.
• Multiplanar Fluoroscopic Check (Strict Lateral View): Confirm that the distal fibula bisects the distal tibial articular arc and is centered symmetrically within the incisura without posterior translation or anterior subluxation.

Step 4: Final Implant Placement (Dynamic Suture-Button vs Cortical Screw)

Definitive stabilization is achieved using either dynamic suture-button constructs or rigid cortical screws according to the surgical plan:

Option A: Dynamic Suture-Button Fixation (Preferred Evidence-Based Technique):

• Drill across four cortices (lateral fibula, medial fibula, lateral tibia, medial tibia) at a level 2.5 to 3.5 cm proximal to the tibial plafond. The drill bit must be oriented strictly parallel to the ankle joint line in the coronal plane and angled 20 to 30 degrees anteriorly from the coronal plane along the transmalleolar axis. Use the manufacturer-specified calibrated drill bit (typically 3.2 mm or 3.7 mm).
• Pass the long guideneedle carrying the high-strength UHMWPE suture-button construct from lateral to medial through the drilled drill tunnel.
• Visualize Medial Button Deployment: Through the medial mini-open counter-incision, directly observe the oblong button as it exits the medial tibial cortex. Ensure the button toggles, rotates 90 degrees, and rests completely flush against the medial tibial bone surface. Verify that the saphenous nerve and great saphenous vein are completely free from button impingement.
• Tension: Maintain the ankle in neutral 90-degree dorsiflexion. Progressively pull the tensioning sutures on the lateral side to seat the lateral button or washer flush against the lateral fibular cortex or through an empty hole in a lateral neutralization plate. Tension firmly until solid resistance is felt; avoid excessive cinching that would deform the fibula.
• Dual Button Strategy: In high-energy Maisonneuve fractures, severe rotational instability, or heavy athletic individuals, deploy a second divergent suture-button construct placed 1 cm proximal to the first implant to control multiplanar rotational torque.

Option B: Rigid Cortical Syndesmotic Screw Fixation:

• Drill 2.5 to 3.5 cm proximal and parallel to the tibial plafond, angled 20 to 30 degrees anteriorly. Use a 2.5 mm drill bit for a 3.5 mm cortical screw, or a 3.2 mm drill bit for a 4.5 mm cortical screw.
• Cortical Purchase: Select either 3-cortex purchase (lateral fibula, medial fibula, lateral tibia) to allow physiologic micro-motion and decrease fatigue breakage, or 4-cortex purchase (bicortical tibial engagement) for high-energy unstable patterns.
• Position Screw Technique: Insert a fully threaded cortical screw through the fibular plate or directly onto bone with a washer. Never use a lag screw technique (do not over-drill the near cortex). The screw acts as a neutral position spacer, not a compression device.
• Tighten: Tighten the screw by hand using a two-finger technique while holding the foot in neutral 90-degree dorsiflexion, avoiding mortise overcompression. Remove the provisional K-wire.

Critical Move

The irreversible procedural step is direct visual and tactile verification of concentric fibular seating in the incisura prior to clamp tightening, confirmed by multiplanar fluoroscopy in mortise AND true lateral planes before implant deployment.

Placing clamp tines blindly across the malleoli in a transverse coronal plane forces the fibula into posterior translation and internal rotational malreduction. Once a rigid screw is drilled or a suture-button is cinched across a malreduced fibula, the mortise is locked into pathological incongruity. Direct visualization of the Chaput-Wagstaffe junction and true lateral fluoroscopy confirming that the fibula bisects the tibial plafond are the definitive visual and tactile safety checkpoints that guarantee anatomical restoration.

7. Pearls and Pitfalls

Pearls

• Direct Incisura Visualization: Never rely on closed or percutaneous reduction. Perform a 2 cm anterior mini-arthrotomy to directly inspect the incisura; debriding torn AITFL shreds eliminates mechanical blocks to reduction.
• The Anterior Third Clamp Rule: Position the medial tine of the reduction clamp strictly on the anterior third of the medial tibial cortex. This matches the natural 20-to-30-degree anterior-to-posterior incisural axis, driving the fibula anteriorly into its anatomical bed rather than pushing it posteriorly.
• Mini-Open Medial Counter-Incision: Always make a small 1.5 cm incision over the medial tibia when placing a suture-button construct. Direct visual confirmation that the medial button is seated flush on cortical bone prevents soft-tissue interposition and catastrophic secondary loss of tension.
• Neutral Ankle Dorsiflexion: Hold the foot in 90 degrees of neutral dorsiflexion during implant tensioning or screw tightening. This ensures that the wider anterior talar dome is accommodated within the mortise, avoiding joint constriction.
• Fix the Posterior Malleolus First: In trimalleolar fractures with Volkmann fragments (>= 10 to 20% of articular surface), anatomical reduction and rigid screw/buttress plate fixation of the posterior malleolus from a posterolateral approach directly re-tensions the PITFL and stabilizes the posterior incisural wall, frequently restoring complete syndesmotic stability without requiring trans-syndesmotic implants.

Pitfalls

• Clamp-Induced Malreduction: Applying a reduction clamp in a purely transverse coronal plane drives the fibula into posterior translation and internal rotation. Rescue: Immediately remove the clamp, manually re-align the fibula with forward thumb pressure, and re-apply the clamp with the medial tine on the anterior third of the tibia, verifying symmetry on a true lateral fluoroscopic view.
• Overcompression via Lag Technique: Using a partially threaded screw or over-drilling the near cortex creates a lag effect, overtightening the syndesmosis and eliminating physiologic micro-motion, which results in chronic lateral ankle pain and stiffness. Rescue: Always use fully threaded position screws across all engaged cortices, or convert to dynamic suture-button fixation.
• Saphenous Nerve or Vein Entrapment: Passing the medial suture-button needle blindly through skin risks transfixing the saphenous nerve and great saphenous vein. Rescue: Make a formal medial mini-incision down to bone, place blunt retractors, and pass the needle directly under direct vision.
• Premature Full Weight-Bearing on Rigid Screws: Unrestricted weight-bearing before 6 weeks with rigid syndesmotic screws leads to fatigue failure, screw breakage, or osteolysis. Rescue: Enforce strict non-weight-bearing for 6 weeks when using cortical screws, or utilize flexible suture-button constructs which tolerate earlier progressive loading.

8. Postoperative Care

Immediate

Immediate postoperative management focuses on wound protection, edema reduction, and rigid joint immobilization:

• Immobilization: Application of a bulky, well-padded posterior plaster splint with supportive U-splint (sugar-tong) extension, maintaining the ankle rigidly at 90 degrees neutral dorsiflexion.
• Weight-Bearing Status: Strict non-weight-bearing (NWB) on the operative extremity using crutches, a walker, or a rolling knee scooter for the initial 2 to 6 weeks depending on construct selection (suture-button allows progressive partial loading at 2 to 4 weeks; rigid screw fixation mandates NWB for 6 weeks).
• Elevation and Cryotherapy: Continuous elevation of the operative limb above the level of the heart for the first 48 to 72 hours, accompanied by cryotherapy to minimize soft-tissue swelling and incision tension.
• Venous Thromboembolism (VTE) Chemoprophylaxis: High-risk immobilized patients receive low-molecular-weight heparin (enoxaparin 40 mg subcutaneously daily) or direct oral anticoagulants during the non-weight-bearing phase.

Rehabilitation Protocol

Rehabilitation progresses through four structured clinical phases:

9. Outcome

Functional, clinical, and radiographic outcomes following syndesmotic stabilization have been extensively characterized in high-quality Level I randomized controlled trials and prospective comparative series:

• Validated Patient-Reported Functional Scores: High-level multicenter randomized trials demonstrate that dynamic suture-button fixation achieves superior functional outcomes compared to rigid syndesmotic screws. Patients treated with suture-buttons display statistically and clinically significant improvements in Olerud-Molander Ankle Scores (OMAS), American Orthopaedic Foot & Ankle Society (AOFAS) scores, and Manchester-Oxford Foot Questionnaire (MOXFQ) indices at 1, 2, and 5 years postoperatively.
• Reduction Accuracy and Maintenance: Bilateral post-operative axial CT comparative trials (Andersen et al. 2018, Ræder et al. 2020) show a 0% malreduction rate in dynamic suture-button cohorts compared to 12% to 15% persistent malreduction in rigid screw cohorts (p = 0.002). Dynamic fixation allows the fibula to settle physiological into the incisura under functional weight-bearing loads.
• Return to Work and Athletic Competition: Meta-analyses of randomized trials confirm that individuals stabilized with flexible suture-buttons return to full occupational duties and competitive athletics significantly faster (mean difference of 3 to 6 weeks) than those stabilized with rigid cortical screws.
• Mid- and Long-Term Survivorship: At 5 to 6.6 years of prospective follow-up (Ræder et al. 2020, Lehtola et al. 2021), the functional advantages of dynamic suture-button fixation are sustained, with significantly lower secondary operation rates (avoidance of planned implant removal) and a lower incidence of radiographic post-traumatic osteoarthritis.

10. Complications

Surgical stabilization of the syndesmosis presents specific mechanical and biological complications that vary according to the implant construct utilized:

Management of Malreduction: If postoperative CT reveals syndesmotic malreduction (> 2 mm translation or > 5 degrees rotational deformity), early revision within 2 to 3 weeks is recommended before mature fibrous scarring occurs. Revision entails open exploration, complete debridement of the incisura, anatomical re-reduction under direct vision, and revision stabilization with dynamic suture-button constructs.

11. Evidence-Based Synthesis

Modern clinical decision-making is grounded in high-quality randomized controlled trials and prospective registry analyses, corroborated by seminal biomechanical and anatomical descriptions.

12. References

• Ræder BW, Stake IK, Madsen JE et al. Randomized trial comparing suture button with single 3.5 mm syndesmotic screw for ankle syndesmosis injury: similar results at 2 years. Acta Orthop. 2020. doi:10.1080/17453674.2020.1818175 [Level I: Randomized Controlled Trial]
• Andersen MR, Frihagen F, Hellund JC et al. Randomized Trial Comparing Suture Button with Single Syndesmotic Screw for Syndesmosis Injury. J Bone Joint Surg Am. 2018. doi:10.2106/JBJS.16.01011 [Level I: Randomized Controlled Trial]
• Shimozono Y, Hurley ET, Myerson CL et al. Suture Button Versus Syndesmotic Screw for Syndesmosis Injuries: A Meta-analysis of Randomized Controlled Trials. Am J Sports Med. 2019. doi:10.1177/0363546518804804 [Level I: Systematic Review / Meta-Analysis]
• Lehtola R, Leskelä HV, Flinkkilä T et al. Suture button versus syndesmosis screw fixation in pronation-external rotation ankle fractures: A minimum 6-year follow-up of a randomised controlled trial. Injury. 2021. doi:10.1016/j.injury.2021.06.025 [Level I: Randomized Controlled Trial]
• Ræder BW, Figved W, Madsen JE et al. Better outcome for suture button compared with single syndesmotic screw for syndesmosis injury: five-year results of a randomized controlled trial. Bone Joint J. 2020. doi:10.1302/0301-620X.102B2.BJJ-2019-0692.R2 [Level I: Randomized Controlled Trial]

13. Master Class Pro-Tip

Never rely on a reduction clamp to achieve syndesmotic reduction; use the clamp solely to hold a reduction that was already established anatomically by direct visualization and manual manipulation. Placing clamp tines in a purely transverse vector across the syndesmosis invariably drives the fibula into posterior translation and internal rotational malreduction. Always clear the incisura of soft-tissue debris, align the anterior fibular cortex with the anterior tibial tubercle under direct visual control, angle your clamp 20 to 30 degrees anteriorly matching the true syndesmotic axis, and confirm anatomical concentricity on a true lateral fluoroscopic view before implant deployment.

Master Class Surgical Pearl: Syndesmosis Reduction and Fixation