Hip resurfacing failures

[Guest guest]

We need to remember that what has brought all of us to this group is

the failure of our " native " hip surfaces. If there was a simple one

size fits all solution, there would not be so many disagreements

about treatment and types of surgery.

The metal on metal hip resurfacing technique looks like it will be

an excellent choice for many people. All of us face the risk sooner

or later that the resurfaced hip will fail. In many cases there is

nothing which can be done to prevent it.

Consider this: The femoral resurfacing component is dependent upon

reshaping of the underlying bone, drilling a perfectly aligned hole

in the bone down the center of the femoral neck. The " ball "

component has an uncemented guide pin which slides into the hole and

cement on the underside of the " ball " helps fix it into position.

If this is done correctly, the forces created by our body weight

will be properly transmitted down the leg.

What can go wrong? The femoral neck is the weakest part of the bone

in our hip. As we age, bone mass is lost (osteoporosis) and the

area of greatest loss is in the femoral neck. This is the most

common site of hip fracture in older people. It can sometimes be

treated by operative placement of lag screws. However, if the hip

has been resurfaced, total hip replacement is necessary.

If the lower part of the femoral neck is damaged during resurfacing,

the procedure may fail.

What can we do? 1. Have a bone densitometry exam of Both HIPS and

lumbar spine before surgery. If one hip has been operated, check

the other side. If you have osteoporosis, a THR will be necessary.

It is normal to be euphoric and exuberant about the way hip

resurfacing will change your life. But protect your hip. Weigh the

enjoyment of your activities against the risk of fracture as you get

older.

2. If you have osteoporosis there are effective treatments (but

these take a long time).

3. Prevent osteoporosis! The highest risk is in thin, caucasian and

asian women. Smoking increases risk. men are at risk as well.

Bone loss in women accelerates at menopause. The " old " Hormone

replacement therapy is now in question due to cancer and other risks.

A safer group of medications, (selective estrogen receptor

modulator) " SERM " , has been developed. In the US, the only

available one is RALOXIFENE, marketed as " EVISTA " by Lilly. this is

available only by presciption.

HERE ARE SOME WEBSITES WITH GOOD INFORMATION ABOUT OSTEOPOROSIS

USA: Main FDA WEB SITE http://www.fda.gov/default.htm

Osteoporosis web sites:

The International Osteoporosis Foundation:

http://www.osteofound.org/

This site has links to member societies from Argentina to Yugoslavia

USA: the National Institutes of Health

http://www.nlm.nih.gov/medlineplus/osteoporosis.html

USA : National Osteoporosis Foundation

http://www.nof.org/

CANADA: Osteoporosis Society of Canada

http://www.osteoporosis.ca/english/home/default.asp?s=1

UK: National Osteoporosis Society

http://www.nos.org.uk/

AUSTRALIA: Osteoporosis Australia

http://www.osteoporosis.org.au/html/index.php

NEW ZEALAND: Osteoporosis New Zealand

http://www.osteoporosis.org.nz/

in North Carolina