Use Titanium or SST Plates for Back Surgery

[CHD01]

CHD01 (Mechanical) Dec 9, 2003
I recently had an interesting dicussion with a man (welder by profession) who had back surgery and requested a titanium plate versus SST for his back surgery. The doctor provided this for him, saying either was available but that they normally use SST.

As a mechanical engineer in the chemical industry, I would think that Titanium is for superior to SST in every way except for cost - but the cost difference cannot be that bad compared to other medical costs. I also worried (wondered) if the doctor's training is good enough to recognize that if a plate is Titanium that then I would think the screws had better be titanium also - I would not mix sst and titanium.

The doctor also said that bacteria can gravitate to the plate, interesting, is this true? If so, does anyone know if Titanium is similar.

Bottom line for this thread is - is Titanium or SST better for back surgery, etc?




The more you learn, the less you are certain of.

 

[unclesyd]

Depends on who you ask.
My wife has had both complete knee replacement, twice, and back surgery and I could never get a definitive answer as to which was the best. It was a 50/50 opinion with the doctors and surgeons on which was best. One doctor did tell me that most doctors tend to go with what he trained and started with. Even on the net it turns out to be a u-pickum.

The first knee replacement was supposed to be titanium, but when it went bad after three years a different surgeon was to replace it and we asked for titanium. He told us he didn't do titanium only S/S so we had to go with S/S. The original knee turned out to be S/S even though we were told it was titanium. The back surgery was the same story the surgeon only used S/S.

I've seen reports of trouble with Titanium Hip joints but also that this has been corrected by coating the titanium.
There is also reports of S/S components failing.

There is considerable information at:

http://www.spineuniverse.com/

 

[CHD01]

Thanks for the link, its interesting.

The more you learn, the less you are certain of.

 

[unclesyd]

One thing I left out was the reason for my wife's knee failure. Some +*&%$#@.... saved about $0.50 when he used polyethylene in lieu of ultra high molecular weight polyethylene for the bearing material in the joint.

Do a search on Titanium and S/S.

 

[kenvlach]

There are big differences in biocompatibilities of various stainless steel alloys. Carpenter Technologies has information & a free brochure on medical alloys on their Biodur site

http://www.biodur.com

See the following for a listing of some ASTM, BS & ISO specifications on metallic materials for surgical implants:

http://www.finishing.com/254/78.html

The original question concerned 316L, so mostly SS info, but also some on Co and Ti alloys.

 

[Metalguy]

There have been SCC failures of 316 SS implants, and I'd be surprised if it's still used. But other SS alloys could be immune from this, as should all Ti alloys.

From the strength/weight ratio, I'd go with Ti.

 

[CoryPad]

Metalguy,

316 stainless steel still is used for implants. One huge reason to choose titanium is due to elastic modulus. Bone density/strength is a function of applied force. If a stiff material (e.g. stainless steel) is used for an implant, it carries more force and the surrounding bone weakens. Titanium's lower modulus results in less bone weakening.

Regards,

Cory

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