Anterior Ankle Impingement

Anterior ankle impingement is pain at the front of the ankle caused by bone spurs or thickened soft tissue being pinched when the foot bends upwards. It is common in footballers, runners and dancers, and often follows repeated sprains. Many people improve with activity changes and physiotherapy, and keyhole surgery can remove the tissue causing the problem.

The ankle joint moves the foot up (dorsiflexion) and down (plantarflexion). When the foot bends upwards, the front of the shin bone (tibia) and the top of the ankle bone (talus) come close together. Anything that takes up space at the front of the joint can then be squeezed, causing a painful mechanical limitation of ankle movement. It is sometimes called "footballer's ankle".

What are the symptoms?

• Sharp or aching pain at the front of the ankle
• Pain or restriction when bending the ankle upwards, such as on stairs, when lunging or when squatting
• Swelling or thickening at the front of the joint
• A feeling of blocking, catching or pinching
• Stiffness, especially in the morning or after exercise

Typical triggers include walking upstairs or uphill and deep squatting.

What causes anterior ankle impingement?

There are two main types, and they often occur together:

• Soft tissue impingement: the joint lining (synovium), scar tissue or the joint capsule becomes thickened or inflamed and gets pinched
• Bony impingement: bone spurs (osteophytes) form along the front of the tibia or talus and block upward movement

Common causes include:

• Repeated ankle sprains or chronic ankle instability
• Repetitive upward bending of the ankle in sport or dance
• Changes after a fracture or a cartilage injury

Repeated small injuries to the front of the joint capsule can lead to inflammation of the joint lining, and new bone can form as spurs along the front of the joint. There is also a link with chronic ankle instability, where a weak outer ligament may allow the ankle bone to move forwards as the foot bends up.

How is it diagnosed?

Diagnosis is based on the history and an examination of the ankle, including a test that reproduces the pain when the foot is pushed upwards. Standing X-rays show bone spurs. An MRI scan shows soft tissue thickening, bone bruising and cartilage damage. A CT scan gives detailed 3D images of the bone. The ankle is also checked for related problems such as instability or tendon injury.

Non-surgical treatment

Treatment usually starts without surgery:

• Changing or reducing the activities that cause pain
• Anti-inflammatory medication
• Physiotherapy, including ankle mobilisation and strengthening exercises
• Supportive footwear or orthotics
• An ultrasound-guided steroid injection to reduce inflammation

Steroid injections can be an option for soft tissue impingement. A heel raise in the shoe may also reduce impingement at the front of the ankle.

When is surgery recommended?

If symptoms persist despite these measures, surgery to remove the structures causing the impingement may be recommended. The options include:

• Arthroscopic debridement (keyhole surgery): removal of thickened joint lining, scar tissue or loose fragments
• Arthroscopic or open cheilectomy: removal of bone spurs from the front of the tibia or talus

Any related cartilage damage or joint surface problems may be treated at the same time. Keyhole arthroscopy is the usual surgical approach and also allows the surgeon to inspect the joint surfaces.

A systematic review of 20 studies in the journal Arthroscopy (Zwiers and colleagues) found generally good results after arthroscopic treatment. In the studies that reported it, 74% to 100% of patients rated their satisfaction as good or excellent. The overall complication rate was 4.6%, and 1.1% for major complications. The studies differed too much for the results of different types of impingement to be compared.

A systematic review (Zwiers and colleagues) reported an overall complication rate of 4.6% after arthroscopic treatment for anterior impingement (1.1% major). Risks include stiffness or persistent pain, nerve damage, infection and a very low risk of a blood clot. Some people are not satisfied with surgery.

What is recovery like?

• 0–2 weeks: post-operative boot; partial weight-bearing with crutches
• 2 weeks: wound review; change to supportive shoes; physiotherapy begins
• 2–6 weeks: increased walking and functional movement
• 6–12 weeks: return to normal activities; most patients resume low-impact sport
• 12+ weeks: gradual return to high-impact activity or full sport if pain-free

Results are generally good in the short to medium term. Any later decline probably reflects existing damage within the joint.

How Mr Hester can help

Mr Hester is a dual fellowship-trained foot and ankle surgeon (FRCS Tr&Orth), trained at Guy's and St Thomas' and in Toronto and Calgary, and a member of BOFAS and EFAS. He sees patients privately at The London Clinic, Cromwell Hospital, King Edward VII's Hospital and HCA The Shard. His NHS practice is at King's College Hospital.

Insured patients need a GP referral and an authorisation code from their insurer. Self-pay patients are welcome. To book, call 020 7046 8004.

Frequently Asked Questions

Sources

1. Zwiers R, Wiegerinck JI, Murawski CD, Fraser EJ, Kennedy JG, van Dijk CN. Arthroscopic Treatment for Anterior Ankle Impingement: A Systematic Review of the Current Literature. Arthroscopy. 2015;31(8):1585–1596. PMID: 25801044. https://pubmed.ncbi.nlm.nih.gov/25801044/
2. Ross KA, Murawski CD, Smyth NA, et al. Current concepts review: Arthroscopic treatment of anterior ankle impingement. Foot Ankle Surg. 2017;23(1):1–8. PMID: 28159036. https://pubmed.ncbi.nlm.nih.gov/28159036/
3. Sprains and strains. NHS. https://www.nhs.uk/conditions/sprains-and-strains/