The ankle syndesmosis joint is the articulation of the lower end of tibia and fibula bones just above the ankle joint.
The syndesmosis joint includes a total of three ligaments call
- Anteroinferior talo-fibular ligament (AITFL)
- Posteroinferior talo-fibular ligament (PITFL)
- Interosseous membrane
Injury to these ligaments varies from simple sprain to complete rupture. An associated ankle fracture is common. Syndesmosis injury is also referred as high ankle sprains. They are different that simple ankle sprains in term of the long-term outcomes. Improper stabilization leads to poor outcomes, constant pain and osteoarthritis of the ankle.
The syndesmotic injuries warrant reconstruction of the syndesmosis surgically should any instability identified.
There should be a strong suspicion of the injury when there is an associated ankle fracture and widening of the syndesmosis. An orthopaedic surgeon review is required.
The injuries are investigated by plan x-rays where a classical widening of the distal tibio-fibular over lap is seen. CT scan and MRI scan are helpful to investigate further.
Whenever there is a strong suspicion an examination under anaesthesia is indicated.
Despite, extensive research no common conclusion was made in term of surgical implant used for the stabilization of the syndesmosis.
Recently, more physiologically friendly implant, Suture Button (Tightrope)fixation has gained popularity. There is strong evidence to support its superiority over screw fixation in terms of pain, function and risk of osteoarthritis.1
The Suture Button (Tightrope) does not require routine removal and potentially avoid a second operation.
Randomized Trial Comparing Suture Button with Single Syndesmotic Screw for Syndesmosis Injury.
J Bone Joint Surg Am. 2018 Jan 3;100(1):2-12.
Andersen MR1, Frihagen F2, Hellund JC2, Madsen JE2, Figved W1.