Activity

This depends on your type of hip replacement. No one can ever say how long your implant will last. There are many different modes of failure. We can only quote survivorship at a certain time point after surgery. This means “ how many implants out of 100” are still functioning without having had a revision surgery at a given time point.

Overall implant survivorship is around 95% at 10 years. Few randomized controlled studies exist. Surgeon skill and experience varies tremendously. Patient populations within different studies are often not comparable. Different implant designs and brands within a class of implant type are not always equivalent. Therefore it is difficult to directly compare one hip type of hip replacement with another. There are pros and cons of different hip implants that you should consider. Results vary widely based on surgeon and implant brand.

There are basically three types of hip implants that I use. Click on the headings below to learn more about these types of implants.

Although modern plastics are now very wear resistant, especially in combination with ceramic heads, breakage of these modern thinner more brittle plastics is a concern in patients who are too active. Therefore heavy labor and repetitive high impact activities should be avoided. Metal- on metal bearings only wear excessively when implanted incorrectly, but can tolerate high impact activities otherwise. Titanium stems of total hip replacements are more durable than plastic liners but may be subject to fatigue failure after long-term extreme impact activities.

Metal-on-metal bearings are biomechanically similar to the native hip bearing. Implant size is based on a patient’s natural anatomy. They are extremely stable and therefore no motion restrictions are required after the initial 6 months. Smaller plastic bearings are inherently biomechanically compromised. Therefore, some permanent restriction on extreme flexion activities is required. 28mm bearings have a 5% dislocation risk, 36mm bearings have a 1% dislocation risk and anatomic-sized metal bearings have a 0.3% dislocation risk.

Total hip stems are more rigid than the surrounding bone. The irritation from this causes thigh pain in about 3-5% of patients with a total hip stem. It may become limiting when patients attempt impact activities. This does not occur with resurfacing.

Although cement is still commonly used to fix implants to bone in Europe, in the US > 95% of hip replacements are of the uncemented (bone-ingrowth) type. Cement is a weak link that breaks down over time. I only use uncemented fixation in the hip.

There is no difference visible in the gait of patients with resurfacing or total hip replacement. However 4/5 laboratory gait studies show that gait is normal with resurfacing while it is not with total hip replacement. Two comparative (Barrack, Noble) survey studies have shown that a higher percentage of resurfacing patients are able to return to desired sporting activity than total hip patients.

It appears that there is no functional difference between resurfacing and total hip for the vast majority of patients who have an arthritic hip. Large metal-on-metal bearings in total hips and resurfacing provide superior stability with a small risk of adverse wear failure if the acetabular component is malpositioned. Resurfacing has the added benefits of bone preservation, thigh pain avoidance, and a better tolerance of impact activity.

Infection

The national postoperative infection rate is 1-2%. My infection rate is 0.1%. With aggressive management even these rare infections can usually be cured without loosing the implants.

Late infections that spread to the hip from other sites are rare. I estimate a lifetime risk of less than 1%. I recommend that patients with hip implants treat bacterial infections anywhere in their body promptly. Viral infections do not pose a threat. You should clean out all cuts with betadine and apply Neosporin ointment to prevent infections.

Prophylactic antibiotics are recommended for dental work and cleaning, as well as for any procedures done through a contaminated space. Your dentist or doctor performing the procedure should be notified that you have a hip implant and antibiotics should be requested. Typically a single dose prior to the procedure is all that is required. Risks of a single antibiotic dose are minimal. There is controversy about this recommendation, and no conclusive data exists. Treating late implant infections is difficult, traumatic and expensive.