A pathologic fracture is a broken bone that’s caused by a disease, rather than an injury. Some conditions weaken your bones, which makes them more likely to break. Everyday things, such as coughing, stepping out of a car, or bending over can fracture a bone that’s been weakened by an illness.

Pathologic fractures don’t always have symptoms. When they do, they share the same symptoms as an injury-related fracture. These include:

  • mild to severe pain near the broken bone
  • bruising, tenderness, and swelling near the broken bone
  • numbness, tingling, or weakness near the broken bone

In some cases, it may be hard to tell the difference between symptoms of a pathologic fracture and those of the underlying condition affecting your bones.

Osteoporosis

Osteoporosis is a disease that weakens your bones, making them more likely to break.

Symptoms of osteoporosis tend to appear in the later stages of the disease, when the bones are weak and brittle. Some symptoms include:

Osteoporosis is very common. It tends to affect women more than men. According to the National Osteoporosis Foundation, 50 percent of women and up to 25 percent of men will break a bone in their lifetime because of osteoporosis. It’s also more common in older adults.

Cancer

Cancer is a disease involving unusual cell growth. It can affect almost all areas of your body. Many types of cancer can invade bones and weaken them, causing them to break.

The symptoms of cancer vary widely depending on the type and stage, but general symptoms include:

  • hard lump(s) under the skin
  • swelling and pain
  • swollen lymph nodes
  • fever and night sweats or chills
  • unexplained weight loss
  • changes in appetite
  • changes in bowel function
  • changes in the skin’s appearance
  • fatigue
  • injuries that don’t heal
  • a cough or cold that doesn’t go away

Many harmless conditions share some of these symptoms, but it’s best to discuss them with your doctor just to be sure. Cancer is much easier to treat when caught early. Learn more about early warning signs of cancer.

Osteomalacia

Osteomalacia is a condition that softens your bones. It’s often caused by a lack of vitamin D, which helps your body absorb calcium. Calcium is necessary for bone health, so when you don’t absorb enough of it, your bones start to weaken. This makes them more likely to break.

Symptoms of osteomalacia include:

  • muscle weakness
  • pain, often in the hips
  • fractures

You can usually treat osteomalacia by changing your diet or taking supplements.

Osteomyelitis

Osteomyelitis is an infection in the bone. It’s caused by a bacterial or fungal infection spreading to nearby bones. In rare cases, osteomyelitis leads to a pathologic fracture.

Symptoms of osteomyelitis include:

  • fever
  • chills
  • feeling tired or irritable
  • pain, swelling, or redness at the site of the infection
  • stiffness in the affected area

Other conditions

Other diseases can also lead to pathologic fractures. Some of these include:

Your doctor will diagnose a pathologic fracture by first doing a physical exam. They may also ask you to do certain movements to help identify the broken bone.

You’ll likely need an X-ray, which will give your doctor a clear view of the break. They may also use MRI scans, CT scans, or nuclear bone scans to get a better look.

If you’re not sure what caused the broken bone, your doctor will likely order other tests to check for an underlying condition. These other tests might include:

  • laboratory tests, often to assess calcium levels, blood counts, or both
  • biopsies to check for tumors, infections, or both

Treating a pathologic fracture depends on the underlying condition. Many diseases weaken your bones, but don’t affect their ability to heal. In these cases, you’ll likely just need a cast or a splint. Depending on the location of the fracture, you may need a pin, plate, or screw to hold the bone in place while it heals.

You’ll need to rest and avoid activities that require using parts of your body affected by the fracture while you heal. Recovery can take anywhere from a couple of weeks to several months, depending on the affected body part.

If the fracture was caused by a condition that makes it hard for your bones to heal, you may need additional treatment, such as surgery. Depending on your underlying condition, your doctor may decide it’s best to focus on managing your symptoms.

Pathologic fractures aren’t always preventable. If you have a condition that weakens your bones, talk to your doctor about ways you can reduce your risk of a pathologic fracture.

Depending on your current health, your doctor may suggest that you:

  • Exercise on a regular basis to keep your muscles strong and improve bone health.
  • Get enough vitamin D and calcium.
  • Receive early treatment of the underlying condition.
  • Use prosthetics or assistive devices, such as supportive shoes, a cane, or a walker.
  • Avoid high-intensity activities.

While bone fractures are typically caused by injuries, they can also be caused by an underlying illness, such as osteoporosis. If you have a broken bone without a known cause, talk to your doctor. You may have an underlying condition that’s weakening your bones, making them more likely to break.