Pain on the outer edge of the foot: From self-tests to peroneal tendons – why shock wave therapy can be an option

Every step can become torture; every run or walk is accompanied by a stabbing or pulling sensation on the outside of the foot. Pain on the outer edge of the foot is a widespread problem that is often underestimated. What begins as a harmless pulling sensation can quickly develop into a chronic condition and significantly reduce quality of life. These complaints are not uncommon, especially among athletes, but also among people who spend a lot of time standing or walking for work.

Although the symptoms are clear, finding the exact cause is often complicated. A variety of problems can be hidden behind the pain. Very often, it is the tendons that run along the outside of the ankle – the peroneal tendons – that cause the discomfort.

This article highlights the most common causes of pain on the outer edge of the foot, offers a simple self-test for initial orientation, and explains what treatment options are available. He provides initial practical tips and explains why shock wave therapy (ESWT) can be an effective option in certain cases.

Brief Overview: Peroneal Tendons & Typical Outer Edge Complaints

Pain on the outer edge of the foot is often closely associated with the peroneal tendons. These are two tendons that run from the lower leg through the ankle to the foot: the tendon of the peroneus longus and the peroneus brevis. Their main function is to stabilize the foot and lift it at the outer edge. They are crucial for ankle movement.

But it is precisely this central role that makes them vulnerable to overload. Typical complaints include tendinopathy (overload or inflammation of the tendon) or tenosynovitis (inflammation of the tendon sheath). This manifests itself in pain, especially during strenuous activity such as walking or running, and often also in swelling or a feeling of pressure behind the outer malleolus.

These symptoms usually arise from repetitive, uniform movements, a sudden increase in exercise intensity, or unsuitable footwear. Therefore, an assessment by a specialist, such as one at the general practitioner's office on Romanplatz, is important to determine the exact cause and initiate targeted treatment.

3-Point Self-Test: An Initial Assessment

To get an initial assessment of whether your symptoms could be related to the peroneal tendons, you can perform this simple self-test. It is not a substitute for a doctor's visit, but it can provide initial clues.

• Pressure pain behind/below the outer malleolus: Use your fingers to feel the area directly behind and below your outer ankle bone (fibula). If you feel significant pressure pain there, this is a strong indication of strain on the peroneal tendons.
• Eversion against resistance provokes pain: Sit upright and cross your affected leg over the other. Press your hand against the outside of your foot and try to rotate the foot outward against this resistance (eversion). If this movement triggers pain on the outer edge of the foot, it indicates weakness or irritation of the peroneal muscles.
• Lateral hop test (one-leg hop): Stand on the affected leg and try to gently hop a few times in place. If hopping causes or worsens pain on the outside of the foot or ankle, this is another sign of a possible tendon problem.
  
  

Differential diagnoses: When it's more than just the peroneal tendon

Not every pain on the outside edge of the foot is necessarily a peroneal tendon problem. Sometimes, similar symptoms conceal other causes that require separate evaluation.

• Cuboid syndrome: This is a subluxation (a slight displacement) of the cuboid bone (os cuboideum). The symptoms are very similar to those of peroneal tendon tendinopathy, but a feeling of stiffness in the midfoot may also occur.
• Stress fracture of the 5th metatarsal: A stress fracture, a small crack in the bone, that can occur due to repetitive stress. Pain that increases significantly with exertion and subsides with rest can be a particularly good indication.
• Supination trauma (twisting): A typical outward twist of the foot can injure not only ligaments but also the peroneal tendons. The symptoms are often acute and accompanied by swelling.
• Sinus tarsi syndrome: An irritation in the sinus tarsi, a small cavity between the heel and ankle bones. Pain with exertion, a feeling of instability, and swelling are typical symptoms.
  
  

First Aid: Immediate Help for a Painful Foot

If pain on the outer edge of the foot occurs acutely, you can relieve the discomfort and promote healing with a few immediate measures. Two important principles play a role here:

Load management: This means reducing the load on the foot, but not completely stopping it. Light, pain-free movements are important to stimulate blood circulation. However, avoid anything that increases the pain, such as running or jumping.

PEACE & LOVE principle: This concept is a further development of classic immediate measures such as the PECH rule (rest, ice, compression, elevation) and is divided into two phases.

PEACE (immediately after the injury):

• Protection: Rest the foot for 1-3 days.
• Elevation: Elevate the foot above heart level.
• Avoid Anti-inflammatories: Painkillers can interfere with natural healing.
• Compression: A light bandage can reduce swelling.
• Education: Your body heals best on its own.

LOVE (after the first few days):

• Load: Begin with pain-free exercise.
• Optimism: A positive attitude promotes healing.
• Vascularization: Gentle movements improve blood circulation.
• Exercise: Begin active exercises early.
  
  

When is a doctor's visit essential? Imaging & Assessment

Even with the best self-care measures, it's crucial to know when to seek professional help. A visit to a doctor is absolutely necessary if:

• The pain persists for more than 7–10 days and doesn't improve despite rest.
• You notice significant swelling or redness in the ankle or on the outside of the foot.
• You feel instability in the joint, as if it might "give way."
• The pain is so severe that it severely limits your daily activities or prevents you from walking normally.

The doctor will take a detailed medical history and perform an examination. Imaging techniques are often used to confirm the diagnosis. An ultrasound (sonography) can clearly show tendons and soft tissue, while an MRI (magnetic resonance imaging) provides more detailed insights into bones, ligaments, and tendons. In some cases, an X-ray is also useful to rule out fractures.

Once a precise diagnosis has been established, targeted therapy can be initiated.

Shockwave Therapy (ESWT): An Effective Treatment Option

If conservative therapies such as rest, physical therapy, or orthotics do not provide sufficient improvement, extracorporeal shockwave therapy (ESWT) can be an effective option. This method involves directing high-energy sound waves into the affected tissue.

The ESWT session lasts only a few minutes and is generally well-tolerated. A special device generates the shockwaves, which are then directed via an applicator onto the skin over the painful tendon. The patient feels impulses whose intensity is adjusted. The therapy stimulates the body's self-healing powers, promotes blood circulation and metabolism in the tendons. This allows chronic inflammatory processes to be specifically resolved and healing to be accelerated.

In most cases, three to five sessions spaced approximately one week apart are sufficient to achieve significant improvement. It is important to note that shockwave therapy should not be considered the sole treatment option. It should always be combined with a targeted training program, especially with eccentric exercises, to strengthen the muscles and achieve lasting improvement.

Targeted Exercise Plan: From Beginner to Advanced

To sustainably strengthen the peroneal tendons and avoid re-injury, a progressive exercise plan is essential. Exercises should be performed pain-free and gradually increased.

Beginner:

Isometric Eversion: Sit on a chair. Press the outside of your affected foot against a piece of furniture or a wall. Hold this pressure for 30 seconds. Repeat 3-5 times per day. This exercise strengthens the muscles without movement and is ideal for pain relief.

Intermediate:

Eccentric Theraband Training: Attach a Theraband around your foot and the other end around a stable object (e.g., a table leg). Slowly rotate your foot outward against the resistance of the band (eversion) and then return it to the starting position even more slowly. Focus particularly on the controlled return movement. Perform 3 sets of 10-15 repetitions each.

Advanced:

Balance training on a balance board: Stand on a balance board. The goal is to maintain balance and steer the board as smoothly as possible. The instability trains the deep muscles and improves ankle coordination. Start with short 30-second sessions and gradually increase the duration.

Returning to Sports: Criteria for a Safe Comeback

Returning to sporting activities should not be rushed. A cautious approach is crucial to avoid immediately overloading the newly healed tendons. Pay attention to these three criteria before increasing the load:

• Pain-free: Your feet should be completely pain-free during exercises and in everyday life. This includes walking and light jogging. If pain occurs, it is a clear sign that the tendons are not yet ready.
• Full strength and stability: You should feel stable in your ankle. Compare the strength of the affected side with the healthy side. Both should feel approximately the same. Training on a balance board is a good indicator of whether the supporting muscles are already fully functional again.
• Functional test passed: An important test is being able to perform the lateral hop test (one-legged hopping) again without pain and uncertainty. If you can do several hops in place or even forward without feeling any pain, that's a good sign that you're ready to return to exercise.

It's best to start with short training sessions and increase the duration and intensity gradually. This gives your body a chance to adapt and prevent re-injury.