Peroneal tendinopathy is pain and irritation of the two tendons that run behind the outer ankle bone and along the outside of the foot. These tendons steady the ankle and stop it rolling over. The condition causes pain and sometimes swelling behind or below the outer ankle bone, and it often follows an ankle sprain or a rise in running or walking on uneven ground. Most cases improve with load management and strengthening.
Also known as peroneal tendonitis, fibularis tendinopathy, peroneal tendon pain
Anatomy: where the problem is
Outer side view of the ankle and foot. Highlighted in the diagram: peroneal tendons.
Symptoms
- Pain behind or below the outer ankle bone, or along the outer edge of the foot
- Pain that is worse with activity, especially on slopes or uneven ground
- Swelling or warmth behind the outer ankle bone
- Pain when turning the foot outwards against resistance
- A feeling that the ankle is weak or unstable
- A snapping sensation behind the ankle bone if the tendons slip out of place
Causes and risk factors
- A previous ankle sprain or long-standing ankle instability
- A sudden increase in running, walking or sport
- Running on cambered roads or uneven ground
- A high-arched foot or a heel that tilts inwards
- Worn or unsupportive footwear
What the evidence says helps
- An international consensus recommends that most peroneal tendon problems are first treated without surgery, for at least three months.2
- Conservative treatment includes reducing aggravating activity, footwear changes, a brace or insole where it helps, and progressive strengthening and balance exercises.12
- An ultrasound or MRI scan is used if a tear is suspected or symptoms are not settling.1
- Surgery is considered for tendon tears, for tendons that repeatedly slip out of place, and for symptoms that persist despite good conservative care.12
Things you can try at home
- Cut back on running, hills and uneven ground for a few weeks, and keep active with cycling or swimming
- Wear supportive shoes, and replace any that are worn on the outer edge
- Use an ankle support for activity in the short term if it helps
- Start strengthening the outer ankle muscles with band exercises and progress to calf raises
- Practise single-leg balance once it is comfortable
- Return to running gradually on flat, even surfaces first
When to get urgent help
Contact your GP urgently, call NHS 111, or call 999 in an emergency if you have:
- A foot or ankle that is badly swollen, looks deformed or cannot take weight after an injury: go to A&E or a minor injuries unit
- A hot, red, swollen foot or joint with a fever or feeling unwell: get same-day medical help
- Any foot wound, sore or infection if you have diabetes or poor circulation: contact your GP or foot protection service urgently
- A foot that suddenly becomes cold, pale or numb: call 999
- A pop on the outer ankle with sudden weakness, or a tendon that snaps over the ankle bone: get it assessed promptly
How Apollo can help
We examine the tendons, the ankle ligaments and your foot posture, since instability and foot shape often contribute. Rehabilitation combines load management with progressive strengthening and balance work, and hands-on treatment for the ankle and calf where appropriate. Our podiatry and biomechanics services can assess how pressure passes through your foot and advise on footwear or orthoses. If we suspect a tear or the tendons are slipping, we refer you for a scan and a specialist opinion.
No GP referral needed. Clinics in Sheringham, Coltishall and Norwich.
Related reading
Frequently asked questions
How long does peroneal tendinopathy take to heal?
With reduced loading and a strengthening programme, many people improve over six to twelve weeks. Long-standing cases, or those with ankle instability, can take longer.
Can I run with peroneal tendinopathy?
It is usually best to reduce running for a few weeks, especially on slopes and uneven surfaces, and keep fit in other ways. Running can be reintroduced gradually as the pain settles and strength returns.
Is this related to my old ankle sprain?
Quite possibly. The peroneal tendons work hard to stop the ankle rolling, and they can be strained in a sprain or overloaded afterwards if the ankle remains unstable. Rehabilitation that restores strength and balance addresses both.
References
- Davda K, Malhotra K, O’Donnell P, Singh D, Cullen N (2017). Peroneal tendon disorders. EFORT Open Reviews 2:281-292. View source
- van Dijk PA, et al. (2018). The ESSKA-AFAS international consensus statement on peroneal tendon pathologies. Knee Surgery, Sports Traumatology, Arthroscopy 26:3096-3107. View source
This page is general information, not a diagnosis or a substitute for medical advice. If you are worried about your symptoms, speak to your GP or a registered healthcare professional. Content prepared from the sources above, November 2026.
