Lump On Top Of Foot

A lump on top of the foot is a common problem which can affect people at any age.

The foot lump may be hard or soft, painful or painless, small or large and may have developed suddenly or gradually.

Swelling may have developed as a result of an injury or the bump may have appeared due to an underlying foot condition.

In most cases, a bump on top of the foot is nothing to worry about but any new growth should be examined by your doctor to rule out any serious conditions.

Here we will look at the common causes of a lump in the top of the foot, how they present, why they develop and how to treat them. 

The most common cause of a lump on top of the foot is a cyst. Foot cysts are non-cancerous (benign) lumps, typically round or oval-shaped that are filled with thick, clear, jelly-like fluid.

There are two types of cyst that can cause a lump on top of the foot:

• Ganglion Cyst: a sac of thick fluid that forms a soft lump along the top of the foot, usually near one of the tendons or joints, just underneath the skin. A ganglion usually forms a small, pea-sized lump on top of the foot but the lump can grow to the size of a golf ball. 
• Digital Mucous Cyst: a small pocket of fluid that typically forms a lump on top of the toes. A lump on top of the foot from a mucous cyst is typically less than 1cm wide.

Mucus cysts and ganglion cysts are very similar and look and feel like smooth, spongy bumps on top of the foot or toes. The main difference is where they occur. Ganglion cysts can cause a lump anywhere on top of the foot whereas mucous cyst lumps tend to develop on top of the toes, particularly around the nail.

Digital mucous cysts and ganglion foot lumps are both completely harmless and are usually painless unless they press on one of the foot nerves, which can lead to a burning pain or tingling and numbness. If the cyst is located near one of the joints in the foot it can interfere with ankle, foot or toe movement. 

Ganglion cysts are the most common cause of a soft lump on top of the foot, typically occur between the ages of 20-40 and are more common in women than men. Digital mucous cysts are more common in people over the age of 50. 

A ganglion lump or cyst on top of the foot that isn’t causing any pain or stiffness does not require any treatment, but if it starts causing problems then your doctor may decide to drain the fluid (aspiration) or surgically remove the cyst (excision).

The most common cause of a hard lump on top of the foot is a bone spur.

Bone spurs occur when small growths of bone, known as osteophytes, form on or between the foot bones resulting in a bone bump.

A bone spur on top of the foot may be caused by:

• Damage: to one of the bones or joints in the foot from an injury, wear and tear or inflammation can result in a hard bump on top of foot. The most common cause here is osteoarthritis.
• Repetitive Pressure: through the bone or joint e.g. from altered foot biomechanics, over-training or wearing ill-fitting shoes
• Excessive Friction: on the bone e.g. muscle tightness will result in tension where the tendon attaches to the bone which pulls on the bone causing excess bone growth

Two common types of bone spurs that cause a lump on top of the foot are:

• Metatarsal Exostosis: Bone spurs on one of the metatarsal foot bones
• Metatarsocuneiform Exostosis: bone spurs that forms between the big toe and second toe bones

A bone bump on top of the foot is not normally painful unless it is associated with arthritis, but a bone spur often becomes uncomfortable if it rubs on footwear.

Another common cause of a lump on top of the foot, particularly around the big toe, is gout.

A foot lump from gout is caused by a build-up of uric acid crystals in one of the joints, most typically the big toe.

If your big toe is swollen, red, painful and hot, chances are your foot bump is due to gout.

Gout is more common in men than women and has been linked with certain medical conditions (e.g. diabetes and high blood pressure), diet, obesity and genetics.

If your doctor suspects the lump on top of your foot is due to gout, they may order blood tests or take a sample of fluid from the lump to test for uric acid crystals.

Find out more about the causes, symptoms and how to treat a gout lump on top of your foot in the Foot Gout section.

A hard, painful lump on top of the foot can be due a break in one of the foot bones from a:

• Fracture: a sudden break in the bone due to an injury e.g. direct impact, twisting or a fall. If the bone is displaced, it may stick out slightly causing a visible, painful lump on top of foot.
  
  
• Stress Fracture: a small, hair-line break in one of the foot bones from repetitive over-loading e.g. suddenly increasing training levels. There may be swelling and a small bump on top of the foot over the injured area.

If you have a hard, painful lump on top of your foot that developed after an injury, or you are have recently taken up a new sport or increased your activity levels, your doctor should send you for an x-ray to check for fractures.

Treatment for a bone bump on top of the foot will depend on the type, severity and location of the foot fracture and may involve wearing a specially designed splint, boot or shoe to protect the foot and take pressure off the top of foot bump.

If you think the lump on top of your foot is from a fracture, check out the foot stress fractures section to find out more about the causes, symptoms, diagnosis and best treatment options.