A lump on your collarbone may be cause for concern. This long, thin bone connects your shoulder to your chest. It runs just beneath the skin’s surface and is generally smooth. This makes any lump or bump on the bone easy to notice and feel.

A lump may be a sign of injury, infection, or a more serious condition. You may have an idea of what caused the lump or it may have appeared out of nowhere.

What causes a lump on the collar bone?

There are a number of reasons why a lump can appear on the collarbone. Some of these include:

Injury

An injured collarbone can range in severity. Your collarbone connects to your shoulder and it can become dislocated from your shoulder joints. You may also experience a break or fracture because the bone is so close to the top of the skin. These injuries can occur if you play sports or experience trauma, such as in a car accident or after a fall.

You may have other symptoms if your collarbone is injured, fractured, or broken. You will likely experience:

  • pain
  • swelling
  • difficulty moving your arm upward

Children and teens may be more susceptible to these injuries because the collarbone does not become mature until age 20. Older adults may also experience more injuries to the collarbone because of weaker bone density.

Swollen lymph nodes

Your body has more than 600 lymph nodes. Your lymph nodes and the lymph fluid that filters through them are essential to keeping out unwanted bacteria and foreign substances in your body as well as circulating white blood cells, which also fight infection.

Lymph nodes can become swollen if you have an injury or are fighting an infection or other illness. This is because your body carries more white blood cells to this area to combat the problem. This can result in swelling and a lump near your collarbone.

If the swelling doesn’t go away after a few weeks, see your doctor. They can rule out serious conditions.

A cyst

A lump on the collarbone may be a cyst. Cysts are located under the skin and occur when fluid fills into a sack. These feel hard when you press on them from the skin’s surface and are not usually harmful or a sign of any other health condition.

A tumor

There is a possibility that the lump on your collarbone is a tumor. Tumors can be either benign or malignant and should be reviewed by a doctor.

Many benign tumors are known as lipomas. These are fat-filled tumors that will appear over a long period of time, usually months or years. They will feel soft and squishy if you touch them and are small in size like a pea. The largest are generally smaller than a quarter.

Another type of tumor is a bone tumor. This type of tumor is not common on the clavicle. One percent or fewer of bone tumors on the body occur here.

One type of rare bone tumor of the collarbone is called the aneurysmal bone cyst. These occur most commonly in older children and teens and can be benign or cancerous.

Infection

Discovering a lump on the collarbone may be a sign of infection. One type of infection that could affect the collarbone is a bone infection known as osteomyelitis, though this is not a common condition in the clavicle. Infections can spread to your collarbone from blood or tissue near your collarbone.

You may also experience an infection if the collarbone is injured and germs infiltrate the area.

How to treat a lump on the collar bone

Treatment for a lump on the collarbone varies based on the cause of the lump. Your doctor will need to diagnose the lump in order to determine proper treatment.

To treat collar bone injuries

Injuries, fractures, or breaks of the collarbone will require a range of treatments. These include icing the injury, taking pain-relieving medication, and using an arm sling or brace to secure the collarbone and help heal the injury.

Some injuries may require surgery and physical therapy as well.

To treat swollen lymph nodes

Swollen lymph nodes can be treated based on the cause of the condition. The condition may be the result of an infection, and you will be treated with medications like antibiotics or antivirals for a few weeks.

You may need more aggressive treatments if the swollen lymph nodes are the sign of a more serious health condition.

To treat cysts

A cyst on your collarbone may need very little treatment. Sometimes cysts can go away without any medical intervention, and other times your doctor may advise draining it.

To treat tumors

A tumor will be treated on a case-by-case basis. It is likely your doctor will biopsy the tumor to determine whether it is benign or malignant. This will guide your doctor on the best treatment options.

Your doctor may recommend surgery to remove the tumor, along with follow-up procedures or medications. In some cases, your doctor may recommend removing all or part of the bone affected by the tumor.

To treat infections

Infections may be treated with medications like antibiotics. Your infection may be in the bone, and osteomyelitis could require more serious interventions. Removing the area of the bone affected by the infection or conducting muscle flap surgery could be necessary. You may even need several weeks of intravenous antibiotic treatment to cure the infection.

What is the outlook for a lump on the collar bone?

A lump on the collarbone should be reviewed by your doctor. You may find that the lump is harmless and will go away without treatment, or you may learn that you need more specific treatment to target the lump and any other underlying health conditions.