Syndesmotic transfixation with suture and button (suspensory fixation)
1. General considerations
Syndesmotic injuries and isolated injuries to ligaments are rare before skeletal maturity.
Ligaments are generally stiffer than bone, and failure tends to occur through the physis or by avulsion of the ligament attachment at the epiphysis.
The physis begins to close in adolescents approaching skeletal maturity, and the fracture patterns and treatment are similar to adults.
Pronation/external rotation injuries of the ankle may result in a high fibular fracture with disruption of the syndesmosis and tibiofibular instability.
If the syndesmosis is disrupted, the anatomical relationship between the fibula and tibia must be maintained while the ligaments heal. This can be performed with suture-button fixation. This technique should be used with caution if the fibula is length unstable.
The fracture pattern and treatment of skeletally mature adolescents is identical to adult patients. Isolated ligament injuries are more common in this age group.
The radiological appearance of the distal tibial physis should be assessed and the remaining growth estimated.
Treatment of an associated medial collateral (deltoid) ligament injury
Avulsed or ruptured medial collateral (deltoid) ligament does not usually need fixation. It may, however, block tibiotalar reduction and the incarcerated ligament must be removed from the joint.
Associated high fibular fractures
A fracture of the middle or proximal third of the fibular shaft may be part of a more complex injury and is often underestimated.
High fibular fractures may be associated with instability of the syndesmotic complex.
Restoration of length, axis, and rotation of the fibula at the level of the ankle joint is of primary concern.
The proximal fibular fracture is usually indirectly reduced and rarely requires separate fixation to increase the overall stability.
After transfixation of the syndesmosis, ankle joint stability should be assessed.
2. Instruments and implants
Although insertion of a suture and button can be performed with standard instrumentation, there are specialized implant inserters available and facilitate minimally invasive placement of sutures (refer to the manufacturer’s technical guide).
3. Patient preparation
Place the patient in a supine position on a radiolucent table with a block under the lower leg proximal to the heel.
4. Skin incision for syndesmosis stabilization
Use an image intensifier to determine the correct level.
Incise the skin slightly posterior and lateral to the fibula, proximal to the tibial physis at the level of the planned suture insertion.