Pelvic insufficiency fractures (PIFs)

A pelvic insufficiency fracture means a bone in the pelvis has fractured because it is weak or thin. This can happen after radiotherapy to the pelvic area.

What are pelvic insufficiency fractures (PIFs)?

Pelvic insufficiency fractures (PIFs) are a type of fracture that can affect the pelvis. They can happen when the pelvic bone is weakened. PIFs can be caused by radiotherapy to the pelvis. The pelvis is the lower part of the tummy (abdomen) between the hips. The bones in this area are called the pelvic bones.

Pelvic radiotherapy and PIFs

Radiotherapy can sometimes cause changes to the bone in the area being treated. It is most likely to happen when radiotherapy is given to the pelvic area. Changes to the bone may mean the pelvis cannot cope with the normal stresses put on it. This may increase the risk of small cracks or fractures. PIFs are most likely to happen in the first 2 years after pelvic radiotherapy.

Radiotherapy treatment may be used to treat cancer of the:

  • womb
  • cervix
  • prostate
  • bladder
  • anus
  • rectum.

You are more likely to have a PIF after pelvic radiotherapy if you:

  • are over the age of 50
  • are post-menopausal
  • have a higher risk of osteoporosis.

Looking after your bones can help to reduce your risk.

Symptoms of PIFs

PIFs do not always cause obvious symptoms. They may show up on a scan that is done for another reason.

If they do show symptoms, they can range from a mild ache to severe pain. There may be pain in the lower back or pelvis when moving. This can make walking difficult. Pain is not usually a problem when resting or sleeping.

If you have pain in a bone, always tell your GP or cancer doctor. They can arrange tests to find out what is causing it and give you treatment if needed.

About our information

This information has been written, revised and edited by Macmillan Cancer Support’s Cancer Information Development team. It has been reviewed by expert medical and health professionals and people living with cancer.

Date reviewed

Reviewed: 01 August 2024
|
Next review: 01 August 2027
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