Lateral foot pain can be caused by conditions like muscular fatigue, bunions, tendinitis or sprains. It is often described as a dull, sharp or burning ache that affects the outer foot, and can worsen with tight shoes, high-impact exercises or repetitive movements.

In most cases, lateral foot pain lasts for up about 2 days and is easily treated with ice, rest and elevation. More moderate pain can be managed with over-the-counter NSAIDs or analgesics.

If your lateral pain doesn't improve with conservative measures, or if you have additional symptoms like difficulty weight bearing, difficulty walking, bruising, or swelling, you should see a doctor for further assessment.

Main causes

The most common causes of lateral foot pain are:

1. Muscular fatigue

Muscular fatigue is one of the most common causes of lateral foot pain. It can emerge after a fall, long walks on uneven terrain, exercising without a proper warm-up, ill-fitting shoes or routine changes, like starting a new sport.

How to treat: Elevating your foot can promote adequate circulation and relieve discomfort. You should also rest and apply cold compresses for 10 to 20 minutes, 3 to 4 times per day. Be sure to wrap any cold compresses in a cloth to avoid direct contact with the skin.

2. Abnormal gait

Some people have an abnormal gait that interferes with the way they walk and causes pain in the inner or outer side of the foot. With supination, the foot rolls onto the outer sides of the foot, putting more pressure on the pinky toe. With pronation, the foot steps off of the big toe and lands on the inner part of the foot.

Ideally, you should step off the ball of your foot to ensure weight and impact distributed evenly throughout the foot when walking.

How to treat: If you suspect you have an abnormal gait, you should consult an orthopedic surgeon for assessment. Pain can be relieved with cold compresses, applied for 10 to 20 minutes, 3 to 4 times per day. Treatment may include the use of orthotics to promote a more neutral gait, as well as physiotherapy.

3. Bunions

Bunions, or hallux vagus, are a deformity in the bony joint of the big toe. They cause large, painful bumps below the big toe on the side of the foot, and can be caused by genetic factors or using tight shoes.

The formation of a bunion is usual gradual, and one of the initial symptoms is pain on the inner side of the foot.

How to treat: Treatment is aimed at increasing the space between the big toe to the second toe, and this can be achieved with exercises, more comfortable footwear and orthotics. However, these interventions do not cure the bunion, but rather help to treat discomfort.

If you notice swelling in the area, you can apply cold compresses for 10 to 20 minutes, 3 to 4 times per day (being sure not to apply it directly to the skin). Very severe deformities may require surgical repair.

4. Tendinitis

In most cases, tendinitis in the foot is the result of repetitive movements or from high impact exercise, like jumping rope or running. Pain can be felt on the inner or outer side of the foot.

A tendinitis diagnosis is confirmed by the doctor through direct assessment and imaging, like ultrasound or MRI.

How to treat: You should elevate the affected foot and apply cold compresses for 10 to 20 minutes, 3 to 4 times per day day. If pain and swelling persists even after an adequate rest period, the doctor may require more targeted treatment with medication and physiotherapy.

Read more about tendonitis treatment your doctor may recommended.

5. Sprain

A sprain is an ankle injury that can cause pain that radiates to the lateral foot. The sprain can be caused by a muscle strain or tear, and can occur after high impact exercise (like jumping rope or running) or accidents, like abrupt falls or direct trauma.

How to treat: You should seek medical attention following a suspected sprain. The doctor will likely recommend elevation, cold compresses and immobilization. Anti-inflammatory or analgesic medication can also help to manage pain in the initial phases.

6. Cuboid syndrome

Cuboid syndrome is characterized by misalignment of the cuboid point in the foot. This can occur due to using ill-fitting shoes, repetitive movements or direct trauma, like a sprain. Cuboid syndrome can also emerge due to overloading on the bone from obesity.

Other symptoms of this condition include foot weakness, decreased sensitivity and overall discomfort with walking..

How to treat: You should consult an orthopedic surgeon to confirm a diagnosis and initiate treatment that aims to reposition the cuboid bone. Anti-inflammatories and analgesics, as well as immobilization, may also be necessary.

7. Stress fracture

A stress fracture on the fifth metatarsal bone can lead to lateral foot pain that usually starts as a dull ache and worsens with activity and weight-bearing and improves with rest. This condition is associated with tiny cracks in the outer bone of the foot, and are most commonly caused by repetitive stress over the area.

Other symptoms of a fifth metatarsal stress fracture include swelling and tenderness in the area, bruising and difficulty walking.

How to treat: Lateral foot pain can often be treated with rest and immobilization of the affected foot. Ice and elevation can also help to reduce swelling and stiffness. You should gradually return to your regular activity, as directed by your doctor or physiotherapist, to reduce the risk for reoccurring fractures.

8. Arthritis

Arthritis can lead to lateral foot pain, especially if the outer foot has undergone past injuries. This pain is described as a dull or aching that is felt deeper within the joints.

Lateral foot pain from arthritis is usually worse when walking or standing, and is associated with swelling, reduced foot mobility and even bone deformities over time.

How to treat: Arthritis can be treated with NSAIDs to reduce pain and swelling and physiotherapy to help strengthen surrounding muscles and improve mobility. Some patient may also benefit from footwear modifications (like wearing orthotics or more supportive shoes) as well as weight loss and management. More severe cases of arthritis may require joint injections and/or surgery.

9. Sural nerve entrapment

The sural nerve is a sensory nerve that travels from the calf, to the ankle bone and into the foot. Irritation or compression of this nerve, from an ankle sprain, fracture or repetitive stress, can lead to burning, tingling or sharp pain that is felt on the side of the foot.

How to treat: This condition can be treated by avoiding triggers (like repetitive activities or tight footwear), and by taking medications (NSAIDs, oral steroids and nerve blocks) as directed by your doctor. Surgical intervention to decompress the nerve may be recommended in cases where more conservative treatment has not been effective.

When to see a doctor

You are advised to see an orthopedic surgeon if your lateral foot pain does not improve with time, or if it occurs with other symptoms such as:

Difficulty weight-bearing or walking
Bruising
Intolerable pain that does not improve with medication
Swelling
Pus or discharge

The doctor will evaluate all symptoms and order additional testing, like an x-ray, to identify the cause of pain and to start treatment as necessary.