Metal-on-metal hip implants have a joint made of two metal surfaces:
- a metal ball that replaces the ball found at the top of your thigh bone
- a metal cup that acts like the socket in your pelvis
Most people who have a metal-on-metal implant have well-functioning hips. They usually have a lower risk of serious problems.
Some people's metal-on-metal implants wear down more quickly. This can cause the bone and tissue around the hip to become damaged. You will need medical check-ups to monitor this.
If you have a metal-on-metal hip implant
Metal-on-metal hip implants have been used in a small number of hip replacement surgeries. They are no longer done routinely.
Contact your doctor if you're not sure what type of implant you have. They will discuss any concerns you have about your hip.
If you have a metal-on-metal implant, make sure you:
- go to your follow-up appointments
- are aware of the signs that could mean there's a problem
Non-urgent advice: Contact a GP or surgeon if you have:
- pain in your groin, hip or leg
- swelling at or near your hip joint
- a limp, or problems walking
- grinding or clunking from your hip
These signs do not always mean your implant is failing. But they do need to be investigated.
Tell your doctor about any changes you notice in your general health.
This includes:
- chest pain or shortness of breath
- numbness or weakness
- changes in your vision or hearing
- fatigue
- feeling cold
- weight gain
Risks of metal-on-metal hip implants
Metal-on-metal implants come with some risks.
Wear and tear
All hip implants wear down over time. The ball and cup slide against each other during movements such as walking and running. But certain types of metal-on-metal implants may wear down faster than others.
Tiny metal particles can break off the implant and enter the space around your hip joint. This may trigger inflammation and discomfort in the area. But everyone reacts differently.
If wear and tear is not caught early, it can cause damage to bone and tissue surrounding your implant and joint. This may cause the implant to become loose and cause pain. You will then need more surgery.
Metal ions in your blood
It is recommended to check for the presence of metal ions in the bloodstream. This is usually done at a metal-on-metal hip follow-up clinic.
Ions are electrically charged molecules. The level of metal ions in your blood may show how much wear there is to your implant.
Metal ions in your blood is not blood poisoning. It does not lead to sepsis.
There is no definite link between ions from metal-on-metal implants and being ill. But in rare cases high levels of ions in your blood may affect your heart, nervous system and thyroid gland.
Monitoring your metal-on-metal implant
You should be checked regularly for as long as you have your metal-on-metal implant.
Medical check-ups are:
- a safety measure to lower the small risk of complications
- used to monitor patients who have had metal-on-metal implants for a long time
You will have tests to measure the level of metal ions in your blood.
If you have any signs of a metal-on-metal implant problem, you may need to have an MRI or ultrasound scans. If you do not have any signs, you may still need a scan if the level of metal ions in your blood is rising.
Content supplied by the NHS and adapted for Ireland by the HSE
