Pain on the outer part of the foot is known as lateral foot pain. This type of pain can start gradually or suddenly and can often coincide with swelling, tenderness, a feeling of instability and difficulty walking or doing any sports which involve weight bearing. Lateral foot pain can be caused by a variety of different factors such as poor biomechanics, poor footwear, overuse or trauma. In this blog, we’ll address several common causes of lateral foot pain.
Stress Fracture:
A stress fracture can develop due to repetitive loading in a weight bearing activity such any sport which involves running, jumping or pivoting. Typically, as feet sustain a high level of loading at the bottom of our bodies, they can be prone to stress fractures. A stress fracture on the outer side of the foot will normally develop in the 5th metatarsal or metatarsal head and can lead to a sudden onset of pain which can worsen over time. Pain will typically feel deep and achy and will be worsened through any weight bearing activity. There may also be swelling and tenderness on palpation. Wearing tight shoes may also feel uncomfortable.
Ankle Sprain:
Normally, an ankle or inversion sprain will give rise to lateral ankle pain and is caused through injury to the lateral ankle ligaments. It typically occurs when the foot rolls under the ankle, for example when twisting the ankle stepping off a pavement. This type of injury commonly leads to pain, swelling and a feeling of weakness in the ankle. In 85% of cases, an ankle sprain can lead to lateral foot pain.
Midtarsal Joint Sprain:
A sprain can occur when the ligaments which connect to the mid tarsal joint become injured. This can cause pain on the outside to the middle of the foot.
Peroneus Brevis Tendon Injury:
A common cause of lateral foot pain is when the peroneus brevis tendon becomes injured. Repetitive tension through the peroneal tendons can lead to irritation, inflammation and degenerative change within the tendon. The peroneus brevis tendon inserts onto the 5th metatarsal bone which sits on the outside of the foot. The tendon can become sprained or can even rupture. Typically, symptoms begin gradually and worsen over time. Pain, weakness and warmth at the insertion site are common and a popping sound may be heard.
Cuboid Syndrome:
The cuboid bone is a cube-shaped bone which is positioned in the middle of the outer edge of your foot. It provides ankle and foot stability and connects your foot to your ankle. Cuboid syndrome is frequently underdiagnosed and occurs when the cuboid bone within the foot partially dislocates. It can develop when the peroneus longus muscle in the lower leg applies excessive traction and force onto the cuboid bone. It can also be caused by too much loading through the bone, for example due to excessive physical activity or a lack of recovery time between training sessions. Wearing tight shoes and being obese can also cause cuboid syndrome. This injury can often coincide with peroneal tendinopathy.
Typical symptoms include pain which may extend down to the toes together with weakness and tenderness along the edge of the foot. Any pain is usually worse in the morning and will increase with running or walking, particularly on uneven ground, jumping, hopping, standing on your toes or when twisting the arches of your feet outwards. Pain may also spread to the rest of your foot when you walk or stand. Symptoms tend to ease with rest. If following a lateral ankle sprain there is ongoing lateral foot pain for more than 3 months then cuboid syndrome may well be present as the condition has been found to affect nearly 7% of those affected by an ankle sprain.
Tarsal Coalition:
Tarsal Coalition is a reasonably rare cause of lateral foot pain affecting approximately 1 in every 100 people. This condition occurs when two or more of the foot bones are connected to each other by an excess bar of bone. This is a congenital problem and symptoms usually appear in the second decade of life, normally within the teenage years.
Symptoms often have a sudden onset leading to pain, fatigue and foot cramps which in turn can affect the ability to walk normally. It can cause other foot problems such as ankle sprains and abnormal foot biomechanics. Treatment usually consists of surgery, shoe inserts or casting to immobilise the foot.
Bunions:
Bunions occur when the big toe of the foot rotates inwards and points towards the other toes. It can be caused by a defect within the bone of through wearing tight shoes for long periods of time. As a result, this encourages people to weight bear more through the lateral side of their foot when walking or standing. This can consequently lead to lateral foot pain through excessive loading.
Any lateral foot problem can lead to foot pain and can be caused by a variety of different things. If you’re struggling with lateral foot pain aim to rest your foot and avoid overloading it by reducing the amount of walking, running or any other weight bearing activities. If it doesn’t resolve then seek a thorough assessment, diagnosis and treatment.