Condition Spotlight: Syndesmosis Injury (High Ankle Sprains)

view of the bones of ankles showing where sydesmosis injuries can occur

Anyone who follows the AFL will know of the dreaded syndesmosis or high ankle sprain injury. We all assume it is a nasty injury based on the commentary it gets, but are unsure of just how serious or debilitating it is.

What is a syndesmosis injury?

A syndesmosis injury is also known as a high ankle sprain.  It involves injury to the ligament and soft tissue that keeps the two bones of the lower leg – the tibia and the fibular – together and in alignment.

Syndesmosis injuries are quite traumatic and can result in instability and weakness through the lower leg and ankle. It can also cause damage to ligaments at the front and sides of the ankle during this rotational movement.

Severe syndesmosis injuries may result in a fracture of either the tibia or the fibular.

What does a syndesmosis injury feel like?

A syndesmosis injury will present as pain through the lower leg, just above the ankles.  It is a pain that does not settle with rest and can feel like a cramping sensation or dull ache.

It tends to also get worse with exercise or sport.

Patients will often describe a feeling of weakness or an inability to put pressure through the ankle.  A reduction in the movement of the ankle joint is also experienced, usually through the upwards or ‘dorsiflexion’ movement of the ankle.

There is often less swelling with a syndesmosis injury than there is with a lateral ankle sprain, however, there can be some swelling at the front of the ankle.

What causes a syndesmosis injury?

Syndesmosis injuries are a traumatic injury that occurs due to a rotational force placed on the lower leg.

Generally, there is excessive pressure applied to the outside of the knee when the foot is planted on the ground, which causes this rotational force.

It is rare that they can occur outside of a collision or traumatic force, however, severe ankle sprains may result in injury to the syndesmosis as well.

Who does it affect?

Syndesmosis injuries commonly affect athletes playing in both contact and non-contact sports. These can include those that compete in AFL, rugby, netball and basketball.

Syndesmosis injuries make up approximately 18% of ankle sprain injuries.

How are syndesmosis injuries diagnosed?

Patients who have sustained a syndesmosis injury will struggle to bear weight through the affected ankle.  And they will often experience pain through the front of the ankle and lower leg.

Pain will also be elicited when performing ankle range of motion tests, as well as when applying compression to the lower leg.

Syndesmosis injuries are diagnosed though imaging such as an X-ray or MRI.  It is through these images that the separation between the tibia and fibular can be seen.

It is important to grade the syndesmosis injury as this will guide the level of treatment and intervention required.

  • Grade 1: Mild tenderness, able to place weight on the ankle, minimal swelling. 
  • Grade 2: Moderate tenderness, difficult to place weight through the ankle, moderate swelling.
  • Grade 3: Intense tenderness, cannot place any weight on the ankle, significant swelling.

What are the treatment options for syndesmosis injuries?

Due to the serious nature of a syndesmosis injury, proper treatment is crucial.

Delayed diagnosis and treatment may result in delayed healing and increased pain. The literature available does state that syndesmosis injuries can be a difficult injury (1).

Treatment can include:

  • Ankle braces and taping – This may be required in the long term to support the ankle joint itself, as well as maintain proprioception. Sometimes, ankle lock taping may be enough to provide the support the ankle needs, however often something more rigid such as a brace is more effective.
  • Moon Boots Initially, offloading the affected ankle is crucial as it will assist with pain management and reduce the pressure through the area. This may be required for 6 weeks or more depending on the extent of the injury.
  • Strengthening programs – This will involve various strengthening exercises to help rehabilitate the structures of the lower leg and ankle, as well as the injury itself. It will depend on a number of factors including the severity of the injury and the demands of everyday life or exercise/sport. Exercises may include range of motion exercises, strength exercises and proprioception and balance exercises.
  • Orthotics – Orthotics may be able to help with keeping the ankle in the correct alignment, whether this is post rehabilitation or surgery. They will not be necessary in all cases and may be a short term solution to managing your pain and function.
  • Footwear modifications This can include changing the lacing of the shoes to include a heel lock lacing technique, which stabilises the heel and ankle.  You can learn more about lacing techniques by reading our article “Believe it or knot, there are different ways to tie your shoelaces!“.

Syndesmosis Surgery

Why would I need surgery for a syndesmosis injury?

Surgery is often required for syndesmosis injuries/high ankle sprains to close the gap between the tibia and the fibula.

It is recommended for moderate to severe syndesmosis injuries that have resulted in significant instability through the ankle joint, as well as those who have not responded to conservative treatments.

What is involved in a syndesmosis surgery?

Traditionally, syndesmosis surgery can include fixing the tibia and the fibula together and realigning the syndesmosis with pins and sometimes plates. Research suggests that this is the most common surgical method used, accounting for up to 75% of syndesmosis surgeries (1). This is aimed at preventing the joint from separating further once you begin to place weight through the ankle and recommence walking. One particular study stated that this type of surgery can sometimes delay return to sport, as almost 70% of cases require the pins to be removed 3-6 months after surgery, resulting in a 4-6 month time frame for returning to sport safely (1).

Another surgical method that is becoming increasingly popular is known as the tightrope procedure. This involves holding the tibia and fibula together via a non-absorbable suture, rather than using pins (1). It is increasingly becoming the preferred method as it typically does not require another surgery to remove the hardware and allows for earlier weight bearing and return to activity (1). Some of the literature now states that the return to sport for those who have undergone syndesmosis tightrope surgery have returned to sport in 2 months, making it increasingly more desirable for high level athletes (1).

What is the rehabilitation/recovery process for syndesmosis injuries/surgery?

Immediately following surgery, the ankle is immobilised for the first 10-14 days with little to no weight bearing allowed. This is to allow the syndesmosis joint to heal without excessive pressure being placed on it. Research suggests that there is little consensus on the optimal rehabilitation regime following immobilisation due to a number of factors including prior strength, activity demands, other health conditions and healing capabilities (1).

The rehabilitation process involves range of motion, proprioception and strength exercises, as well as sport specific exercises once baselines levels  (1). Current literature is now leaning towards an accelerated rehabilitation program post-surgery and early weight bearing in order to speed up the healing process.

Do the pins and plates need to be removed?

In some cases, the pins and plates do not need to be removed. However, your surgeon may recommend removing them if they are causing pain or restricting your motion. The syndesmosis joint is designed to move, therefore the hardware is usually removed if it is detrimental to the joint once it has healed.

This is a conversation that you will need to have with your surgeons to determine the best course of action.

How long after syndesmosis surgery can I walk?

As mentioned previously, syndesmosis surgery recovery time will depend on a number of factors, including what surgery you had and how severe your injury was.

Traditionally, patients would be required to avoid all weight bearing for the first 6-8 weeks following surgery, however with the introduction of the tightrope technique, that time frame is thought to have reduced to anywhere between 3-6 weeks.

Your surgeon wild discuss this with you prior to your procedure.

What are the risks of the procedure?

The risks associated with these surgeries are not unlike other orthopaedic procedures.

Possible complications can include reactions to the anaesthetic, damage to the blood vessels or nerves and infections of the wound sites. Any surgery that involves hardware such as pins or plates carries additional risk, with irritation of the hardware and the hardware actually failing also being considered risk factors.

If you’ve injured your ankle or are experiencing pain or discomfort in your feet and or lower limbs, come see our friendly team here at Watsonia Podiatry. To book an appointment, give us a call on 03 9432 2689 or click here to book online.

REFERENCES

  1. Latham, A. J., Goodwin, P. C., Stirling, B., & Budgen, A. (2017). Ankle syndesmosis repair and rehabilitation in professional rugby league players: a case series report. BMJ Open Sport & Exercise Medicine, 3(1), e000175.