Peroneal tendinopathy (also called peroneal tendonitis or fibularis tendinopathy) is an overuse and load-related injury affecting the tendons of the peroneal muscles on the outside of the ankle and foot. The two main tendons are the peroneus longus and peroneus brevis. They run behind the bony bump on the outside of the ankle (the lateral malleolus) and help stabilise the foot and ankle, especially during walking, running, jumping, and quick direction changes.
When these tendons are repeatedly overloaded, they can become painful and sensitive, sometimes with swelling and weakness. People often notice pain when the foot turns outward (eversion), when pushing off to walk or run, or after uneven ground walking. Peroneal tendinopathy is commonly linked with a history of lateral ankle sprains or chronic ankle instability, because the peroneals are forced to work harder to control the ankle after ligament injury.
Physiotherapy for peroneal tendinopathy is a leading treatment approach. A physiotherapist helps settle pain and irritation, then progressively reloads the tendons with targeted strengthening, balance training, and return-to-running or return-to-sport progressions. Your physiotherapist will also address the factors that caused the overload in the first place, such as training errors, footwear, ankle stiffness, or foot posture that places extra stress on the outer ankle. With the right peroneal tendinopathy rehab plan, most people can return to normal activity without surgery.
Key Facts
- Peroneal tendon disorders are commonly mistaken for, or occur alongside, lateral ankle sprains, so ongoing outer ankle pain after an ankle sprain should raise suspicion for peroneal tendon involvement. 🔗
- Hindfoot varus (a tendency to load the outside border of the foot) is a recognised risk factor for peroneal tendinopathy and can increase tendon load during gait and sport. 🔗
- In a surgical cohort study comparing imaging to intraoperative findings, diagnostic ultrasound for peroneal tendon tears showed 88% sensitivity and 100% specificity, while MRI showed 100% sensitivity and 100% specificity in that sample. 🔗
Risk Factors
- Recent or recurrent lateral ankle sprains or chronic ankle instability.
- Hindfoot varus or a tendency to load the outside border of the foot.
- Sudden increase in running distance, speed work, hills, or trail running.
- Inadequate recovery between training sessions or returning to sport too quickly after injury.
- Footwear that is worn out, lacks lateral support, or does not suit your foot shape and activity.
- Reduced ankle dorsiflexion, calf tightness, or poor single-leg balance control.
Symptoms
- Pain along the outer side of the ankle or foot, often behind or below the lateral malleolus.
- Pain that worsens with walking, running, jumping, or uneven ground.
- Tenderness when pressing on the peroneal tendons or when the foot turns outward against resistance.
- Swelling or thickening around the outer ankle, sometimes with warmth after activity.
- Weakness or a feeling of ankle instability, especially with cutting and change of direction.
- Stiffness after rest, such as first steps in the morning or after sitting.
- A popping or snapping sensation, which may suggest tendon subluxation (tendon slipping) rather than simple tendinopathy.
Aggravating Factors
- Running, especially hills, trails, or cambered surfaces that load the outside of the ankle.
- Jumping and landing sports, particularly when landing on an unstable ankle.
- Rapid direction changes or cutting movements (football codes, netball, basketball).
- Foot eversion against resistance or repeated side-to-side movements.
- Unsupportive or worn footwear, especially shoes that allow the foot to roll outward.
Causes
Peroneal tendinopathy usually develops from repetitive strain and progressive overload of the peroneus longus and peroneus brevis tendons. This can occur when training volume increases too quickly, when running on uneven surfaces, or when sport involves repeated cutting and lateral movement. The tendons may also become overloaded when they are required to compensate for other problems, such as reduced ankle mobility, poor balance control, or weakness through the calf and hip.
A common contributor is a history of lateral ankle sprains. After an ankle sprain, the ligaments on the outside of the ankle can remain lax or painful, and the nervous system’s sense of joint position (proprioception) can be reduced. The peroneal muscles often become the body’s “backup stabilisers”, working harder to prevent the ankle from rolling again. Over time, this extra workload can trigger peroneal tendinopathy, especially if sport is resumed before strength and balance are fully restored.
Foot posture and mechanics can also play a role. Some people naturally load the outside of the foot more, particularly those with hindfoot varus or higher arches. Others develop outer-foot loading due to compensation for pain elsewhere (for example plantar fasciopathy, Achilles pain, or knee issues). A physiotherapist will look for these patterns so that treatment targets the true driver of tendon overload rather than only treating the painful tendon.
How Is It Diagnosed?
Peroneal tendinopathy is usually diagnosed with a detailed clinical assessment. Your physiotherapist will ask about the onset (gradual vs sudden), training load changes, surfaces, footwear, and any prior ankle sprains. They will then examine tenderness along the peroneal tendons, swelling patterns around the lateral malleolus, and how symptoms behave with tendon loading tests, such as resisted eversion and single-leg heel raise variations.
A key part of diagnosis is ruling out other causes of outer ankle pain, including lateral ankle ligament injury, ankle impingement, stress fracture, sinus tarsi pain, or peroneal tendon subluxation and tears. Your physiotherapist will also assess gait and single-leg mechanics, because poor control through the hip, knee, and ankle can repeatedly overload the peroneals during everyday walking and sport.
If symptoms are severe, there is snapping, there is significant swelling, pain persists despite appropriate rehab, or a tear is suspected, your physiotherapist may recommend imaging and medical review.
Investigations & Imaging
- X-ray
- Helps rule out fractures or bony contributors to lateral ankle pain, and may identify anatomical variants that irritate the tendons.
- Ultrasound
- Assesses tendon thickening, fluid around the tendons, subluxation during movement, and can help identify tears. Ultrasound can be highly accurate for peroneal tendon tears in surgical cohorts.
- MRI
- Provides detailed evaluation of tendon structure, tears, inflammation, and surrounding joints and ligaments, particularly when symptoms are complex or persistent.
Physiotherapy Management
Peroneal tendinopathy physiotherapy management is built around two goals: settling tendon irritation and restoring the tendon’s capacity to tolerate load. The key is progressive tendon loading, not complete rest, because tendons generally become more sensitive when they are underloaded for long periods. Your physiotherapist will choose the correct starting point based on your pain levels, daily demands, and whether there are signs suggesting a tear or subluxation.
Physiotherapy also targets the contributors that keep overloading the tendon, such as chronic ankle instability, reduced ankle mobility, poor balance control, or a running gait pattern that places repeated stress on the lateral ankle. Effective physiotherapy for peroneal tendinopathy is individualised and includes clear criteria for progressing walking, running, and sport.
Exercise
Peroneal tendinopathy exercises usually begin with exercises that calm pain while maintaining tendon function. Early stages often involve isometric eversion holds (pushing the foot outward into resistance without movement) because this can reduce pain and safely activate the tendon. Your physiotherapist may also use controlled calf work because the peroneals contribute to ankle stability during heel raise and push-off phases of gait.
As symptoms settle, exercises progress to slow, heavy strengthening to build tendon capacity. This commonly includes resisted eversion through range, controlled single-leg heel raises, and lateral step-down patterns that train the ankle to stay stable while load moves through the foot. The key is slow, deliberate movement with good alignment so the tendon adapts rather than flaring.
Later-stage rehab includes energy-storage loading that prepares the tendon for sport, such as hopping progressions, lateral bounds, and change-of-direction drills. Your physiotherapist will time these progressions so the tendon is strong enough to tolerate elastic loads without reactive pain and swelling the next day.
Activity Modification
Activity modification in peroneal tendinopathy rehab is about reducing the specific loads that irritate the tendon while keeping you active. Your physiotherapist may temporarily reduce running, hills, speed work, and uneven surfaces, because these increase lateral ankle demand. In many cases you can maintain fitness with low-irritation options such as cycling, swimming, or deep-water running while you rebuild tendon capacity.
Once pain is improving, your physiotherapist will guide a graded return. For runners, this often starts with walk-run intervals on flat ground, then gradually increases total running time, then introduces hills and speed later. For field sports, return to training typically progresses from straight-line running to controlled agility, then reactive drills, then full training and competition. The goal is consistent progress without repeated flare-ups.
Manual Therapy
Manual therapy can help when stiffness or joint mechanics are contributing to overload. For peroneal tendinopathy, physiotherapists commonly treat ankle dorsiflexion restriction, subtalar joint stiffness, and soft tissue tightness in the calf and peroneal muscles. This matters because limited ankle motion can shift load into compensatory patterns that stress the lateral tendons during walking and running.
Manual therapy is not used as a standalone fix. It is most effective when paired with strengthening and movement retraining, so any temporary improvement in mobility translates into a more stable, less painful gait pattern.
Postural Retraining
“Posture” work for peroneal tendinopathy is usually gait and movement retraining. Your physiotherapist may address excessive outer-foot loading, hip drop during single-leg stance, or a tendency to roll the ankle outward when fatigued. Small changes, like improving cadence, reducing overstriding, and strengthening hip control, can reduce repeated lateral ankle stress.
If chronic ankle instability is present, physiotherapy will include proprioception retraining and reactive balance tasks so the ankle stabilises quickly during unexpected movements. This directly reduces peroneal tendon overload in sport and on uneven ground.
Bracing & Taping
Bracing and taping can be useful, especially when peroneal tendinopathy is linked with recent ankle sprain or ongoing instability. A lace-up brace or rigid sports tape can reduce the risk of the ankle rolling while the tendon is sensitive. This support can also make it easier to begin rehab exercises and return to walking without pain-related guarding.
Your physiotherapist may also advise footwear strategies, including shoes with better lateral support, and in some cases a lateral wedge or posted orthotic if your foot posture increases outer-foot loading. The aim is to reduce tendon compression and traction while strengthening progresses, not to rely on supports permanently.
Dry Needling
Dry needling can help peroneal tendinopathy by providing short-term pain relief, reducing local sensitivity, and improving muscle function in the peroneals and calf. It’s best used as an adjunct to progressive loading rehab, particularly when pain is limiting exercise progress or there’s significant muscle tightness/trigger points contributing to symptoms.
Shockwave
Shockwave therapy may be considered for stubborn lateral ankle tendon pain that does not settle with appropriate loading, particularly when symptoms suggest chronic tendinopathy. Evidence for extracorporeal shockwave therapy across tendinopathies supports pain reduction in some cases, but it should be used alongside a structured strengthening program rather than replacing exercise-based rehab.
Heat & Ice
Ice can help manage pain after activity in early stages, particularly if the tendon becomes reactive after walking or exercise. Your physiotherapist may recommend short ice applications after aggravating activities while you build tolerance. Heat is sometimes used for calf and muscle stiffness, but it is generally less targeted for tendon irritation than load management and strengthening.
Tens
TENS can be used as a short-term pain management tool if peroneal tendon pain is limiting movement or sleep. In peroneal tendinopathy, it is typically an adjunct that helps you tolerate rehabilitation and normal walking, rather than a primary treatment.
Education
Education is critical in peroneal tendinopathy physiotherapy. Your physiotherapist will explain why the tendon became overloaded, how to pace activity so you do not trigger a flare, and what level of discomfort is acceptable during rehab. Many people do best when pain during exercise is kept in a manageable range and when symptoms settle back to baseline within 24 hours.
Education also covers footwear, surface choices, and training structure. For runners, this includes how quickly to increase weekly kilometres, how to reintroduce hills, and how to avoid back-to-back hard sessions that exceed tendon recovery capacity.
Other
Other physiotherapy management may include a running assessment, a return-to-work plan for physically demanding jobs, and coordination with your GP if anti-inflammatory medication is being considered. If your physiotherapist suspects tendon subluxation or a significant tear, they will recommend imaging and specialist review rather than pushing through exercise progressions.
Other Treatments
Other treatments may include short-term anti-inflammatory medication as advised by your GP, and temporary immobilisation in a boot if pain is severe or walking is significantly limited. These options can reduce irritation in the short term, but long-term improvement usually requires progressive loading and movement retraining through physiotherapy.
In some cases, orthotics or shoe modifications are used to reduce lateral tendon stress. This is most helpful when foot posture or gait mechanics are clearly increasing outer-foot loading. Orthotic changes should be reviewed carefully because the goal is to reduce tendon load without creating new problems elsewhere in the foot or leg.
Surgery
Surgery is not common for uncomplicated peroneal tendinopathy. It may be considered when there is a confirmed tendon tear, persistent tendon subluxation, or ongoing pain and dysfunction despite a well-performed rehabilitation program. Surgical procedures depend on the problem and may include tendon debridement (removing unhealthy tissue), repair of tears, or stabilisation of structures that hold the tendons in place.
After surgery, post-operative physiotherapy is essential to restore ankle mobility, rebuild strength, and retrain balance and gait. Your physiotherapist will progress rehabilitation according to the surgeon’s restrictions and your tissue healing response.
Prognosis & Return to Activity
Recovery time varies depending on how irritable the tendon is, how long symptoms have been present, and whether there are associated problems like chronic ankle instability or a partial tear. Many mild to moderate cases improve over weeks with appropriate management, while more persistent cases may take several months of structured strengthening and graded return to sport.
Physiotherapists usually guide return to running and sport using function-based criteria rather than an exact timeline. Typical milestones include: comfortable walking without a limp, good single-leg balance control, the ability to perform repeated heel raises with minimal pain, and the ability to complete sport-specific drills without a flare the following day. Returning too quickly, especially to hills, agility, and uneven surfaces, is a common reason peroneal tendon pain returns.
Complications
- Progression to tendon tear if overload continues and symptoms are ignored.
- Chronic ankle instability with repeated sprains and ongoing lateral ankle pain.
- Persistent swelling and reduced tolerance to running, jumping, and uneven terrain.
- Altered gait leading to secondary pain in the calf, Achilles, knee, or hip.
Preventing Recurrence
- Rehab ankle sprains properly. Completing balance retraining and peroneal strengthening after a sprain reduces reliance on the tendons as “emergency stabilisers” and lowers recurrence risk.
- Progress running loads gradually. Increase weekly distance, hills, and speed work in small steps to avoid sudden spikes in lateral ankle tendon load.
- Choose footwear with lateral stability. Worn-out shoes or shoes that allow excessive outer-foot loading can increase peroneal tendon strain during walking and running.
- Maintain calf strength and ankle mobility. Stiff ankles and weak calves can shift load into compensatory patterns that overload the peroneals, particularly during push-off and uneven ground walking.
When to See a Physio
- If lateral ankle pain persists for more than 1 to 2 weeks, especially after an ankle sprain.
- If you notice snapping, popping, or a sensation of the tendons slipping, which may suggest peroneal tendon subluxation.
- If swelling is significant or pain is sharp and worsening, particularly if a tear is suspected.
- If you cannot return to walking, running, or sport despite rest and basic measures, and you need a structured peroneal tendinopathy rehab plan.