Syndesmotic Injury (High Ankle Sprain)
What is the ankle syndesmosis?
The two bones of the leg (tibia and fibula) are connected just above the ankle by strong ligaments. This complex is called the ankle syndesmosis. It allows a small amount of movement between the leg bones during activities.
What is an ankle syndesmotic injury (high ankle sprain)?
Inwards twisting the leg on a planted foot can tear these ligaments making the syndesmosis unstable. Occasionally the fibula can break high up the leg near the knee (Maisonneuve Fracture).
This pattern of injury is different to the usual ankle sprain where the ankle rolls over the foot and tears the "low" ankle ligaments instead.
Therefore, the term "high ankle sprain" is used for syndesmotic injuries.
Symptoms of syndesmotic injury
Pain is often felt just above the ankle and can spread up the leg. There can also be pain in the inner ankle. Swelling and bruising are often less than expected. A common feeling is instability when trying to pivot on one foot.
Chronic or missed syndesmosis injury can cause long-term ankle pain, weakness during change of direction activities, and even ankle arthritis.
Diagnosis of Ankle Fractures
This injury is often not recognised immediately unless severe or the treating doctor/physiotherapist thinks about it. Fortunately, early treatment is similar to that given for a regular ankle sprain.
Specific examination techniques help make the diagnosis, but investigations are always required to confirm and determine severity.
Weight-bearing X-rays comparing both ankles are useful, with MRI, weight-bearing CT and even ankle arthroscopy sometimes required to determine whether the syndesmosis is stable or unstable.
Treatment of ankle syndesmotic injury
- Clearly stable syndesmotic injuries require reduced weight-bearing with crutches and either a brace or "moonboot" until comfortable.
- Obviously unstable syndesmotic injures need surgery within two weeks.
- Injuries that may be unstable can wait four weeks to assess progress and allow further investigations.Occasionally, people need to know immediately if there is instability (elite athletes, etc) and will undergo ankle arthroscopy +/- syndesmotic stabilisation within two weeks of injury.
- Unstable injuries treated within eight weeks require ankle arthroscopy and syndesmotic stabilisation using one or two Arthrex TightRopes ("keyhole surgery"). This is followed by progressive weight-bearing and a month in a "moonboot" with physiotherapy-assisted rehabilitation.
- Unstable injuries treated after eight weeks still undergo ankle arthroscopy but usually require open syndesmotic reconstruction (Arthrex Internal Brace).
Surgery has small but real risks. TightRope buttons only need removing in 5% of cases. Please see the TREATMENTS menu for further information on ankle arthroscopy.
Treatment Process
Preparation for Surgery
- Provide a complete list of your medications so you can be advises which to stopped prior to surgery,
- Treat any tooth, gum, bladder or bowel problems before surgery to reduce the risk of infection
- Stop anti-inflammatory medications (NSAIDs) at least seven days before the procedure.
- Stop or cut down smoking to reduce your surgery risks and improve your recovery
- Consider losing weight (if overweight) before surgery
Day of Surgery
- Report any infections to me prior to surgery as the procedure cannot be performed until all infections have cleared up.
- Do not consume alcohol - 24 hours prior to treatment,
- Do not eat or drink anything, including water, for 6 hours before surgery
- Avoid vigorous physical activity or exercise 24 hours prior to surgery,
During Surgery
- Administration of general anesthesia or sedation and local anesthesia
- The entire procedure can take 60 minutes to two hours.
- Fractured bone is accessed by making an incision over the ankle area and then specially designed plates are screwed onto the bone, to realign and stabilize the fractured parts
- The incision is then sutured closed and the operated ankle is immobilized with a splint or cast
- Procedure is performed and sent to recovery room, for observation
- Pain medications are prescribed to help with pain during the recovery phase.
After Surgery
- Do not consume large amounts of alcohol after surgery,
- Avoid vigorous physical activity or exercise until advised,
- Follow the Post Surgery Treatment Plan proscribed by the surgeon and post op care specialists.
- Any questions or complications should be communicated directly to the surgeon
Common Questions
If you have a specific question about your treatment, we recommend contacting the clinic