Overview
Unstable disruption of the distal tibiofibular syndesmosis compromises the relationship of the fibula, tibial incisura and ankle mortise. The operative goal is anatomic reduction followed by fixation that maintains that relationship during healing. A technically satisfactory implant position does not compensate for a malreduced fibula or a talus that remains displaced.
Campbell emphasizes direct visualization of the syndesmosis in patients suitable for an open approach. Screw fixation, suture button fixation and selected direct repairs are discussed as different ways to stabilize the injury; selection depends on the instability pattern and associated fracture fixation. (Campbell, Chapter 94.)
Indications and Assessment
Establish whether the injury is stable, partially unstable or completely unstable. Examine the whole injured leg and obtain appropriate radiographs before provocative testing, because associated fractures change both evaluation and treatment. Squeeze and external rotation tests can support the diagnosis when other injuries have been considered.
Stable sprains generally receive nonoperative treatment. Persistent mortise widening after manipulation, complete instability or a relevant associated deltoid injury can lead to operative stabilization. A painful high ankle sprain should not automatically be treated as an operative diastasis. Define the actual mechanical problem and associated injuries before choosing fixation. (Campbell, Chapter 94, pp. 4143–4145.)
Preoperative Planning
Review the fibula throughout its length, the ankle mortise and the medial side of the joint. Determine whether restoration of a fibular fracture is required to recover length and rotation. Plan exposure of the syndesmosis and, for a previously dislocated or substantially subluxed mortise, consider the chapter's recommendation for medial exploration to remove interposed tissue and repair the deltoid as necessary.
Decision | Planning consideration |
|---|---|
Direct reduction | Prepare to inspect or palpate the relationship of the fibula to the incisura and confirm it fluoroscopically. |
Screw fixation | Provides rigid stabilization; determine the protection and possible later removal plan. |
Suture button fixation | Allows some motion; reduction, button seating and the associated fracture construct still require scrutiny. |
Fibular fracture without rigid fixation | Campbell advises against suture button-only stabilization, including the cited Maisonneuve setting. |
Repairable bony avulsion | Consider direct fixation of the fragment; a small unsuitable fragment may require a different attachment repair. |
Discuss loss of reduction, hardware irritation or failure, possible implant removal and the prolonged recovery associated with syndesmotic injury. A flexible implant should not be expected to correct an inaccurate reduction. (Campbell, Chapter 94.)
Positioning and Exposure
Position the patient supine with support beneath the ipsilateral hip to facilitate lateral access. A more lateral position may be needed if posterior ligament visualization is planned. Preserve access to the medial ankle when required. Support the ankle while allowing the heel to float, avoiding an anteriorly displaced talus caused by pressure beneath the heel.
Use a controlled incision along the anterior border of the distal fibula to expose the distal tibiofibular joint. Develop the interval with attention to the surrounding soft tissues. Arrange fluoroscopy so that the mortise and fibular relationship can be checked before and after fixation. (Campbell, Chapter 94, Technique 94.2.)
Surgical Technique
1. Restore the bony framework
Address an associated fibular fracture as required to recover the appropriate length, alignment and rotation. The fracture fixation plan and the syndesmotic fixation plan must work together. Campbell describes fixation through a fibular plate where appropriate; implant selection should reflect the fracture pattern rather than applying the same plate to every injury.
2. Reduce the syndesmosis directly
Seat the fibula in the tibial incisura while restoring the position of the talus in the mortise. Assess the relationship under direct visualization or palpation and with fluoroscopy. Avoid rotating or translating the fibula during provisional stabilization. If a clamp is required, apply gentle, directed compression; an anatomically seated reduction may not require one. Excessive force or a poorly directed clamp can compromise the reduction it is intended to hold.
3. Stabilize the reduction
Under fluoroscopic control, prepare the tunnel for the selected screw, suture button or combined construct. Campbell describes placement approximately 3 cm proximal and parallel to the tibial plafond, with trajectory adjusted to the actual lateral or posterolateral starting point. Keep the reduction controlled during drilling and implant passage. A plate can distribute load and reduce focal subsidence or stress injury, but adds a potential source of lateral irritation.
For screw fixation, plan the cortical purchase and any anticipated removal before insertion. When a suture button is used, confirm appropriate seating and fixation rather than relying on the device's flexibility. Combined fixation is an option in the chapter, not a requirement for every injury.
4. Address associated ligament or avulsion injury
Where a syndesmotic ligament has avulsed with a suitable bone fragment, the chapter's alternative technique favors fixation of the fragment when feasible. A fragment too small for fixation may be excised and the relevant attachment repaired with an anchor. Identify the actual injured attachment rather than treating every avulsion as the same lesion.
5. Final verification
Check the mortise, talar position, fibular position and implant location with intraoperative imaging. If the talus remains displaced, reconsider the reduction and investigate interposed soft tissue, including the deltoid ligament or a tendon. Do not accept residual incongruity simply because the implant has been inserted. Complete any indicated medial treatment, confirm the final construct and close the wound with a protective splint. (Campbell, Chapter 94, Technique 94.2.)
Postoperative Care
Protect the repair and monitor swelling, skin condition and the wound. Campbell's detailed Technique 94.2 protocol describes initial splinting, transition to a cast at two weeks, a walking boot with gentle motion and touch-down weight bearing at five weeks, and weight bearing in the boot at eight weeks. In the screw-based regimen, the boot continues until the planned screw removal around fourteen weeks.
The same chapter discusses earlier weight bearing with selected knotless suture button constructs and the avoidance of routine removal. These statements describe different constructs and should not be merged into one universal timetable. Set restrictions according to the actual fixation, associated fracture or ligament repair and maintenance of reduction on follow-up. (Campbell, Chapter 94.)
Complications and Troubleshooting
Malreduction: reassess fibular rotation and translation, clamp direction and the talar relationship before accepting fixation.
Loss of reduction: evaluate construct stability, associated fracture fixation and progression of loading.
Implant problems: screw breakage, button subsidence and symptomatic hardware are described; implant removal depends on the construct and clinical situation.
Fibular stress injury: isolated button placement can create a stress concentration; load distribution and bone condition matter.
Ossification or synostosis: radiographic ossification is not always disabling, but symptomatic restriction warrants assessment.
Persistent pain: consider residual incongruity and associated ankle pathology rather than assuming the syndesmosis has healed normally.
Technical Pearls
Restore anatomy before choosing how tightly to hold it.
Float the heel during reduction to avoid an unintended anterior talar shift.
Check the reduction directly and with fluoroscopy; neither assessment is infallible on its own.
Investigate a blocked mortise rather than forcing reduction with a clamp.
Match loading and implant removal plans to the actual fixation method.
References
Richardson DR. Sports injuries of the ankle. In: Azar FM, Sawyer JR, Throckmorton TW, eds. Campbell's Operative Orthopaedics. 15th ed. Elsevier; 2026. Chapter 94, syndesmotic injury diagnosis, operative treatment and fixation, pp. 4143–4148; Technique 94.2 and alternative direct anatomic repair on p. 4148.e1.