How to Shop for a New Knee

Health Professional

Are you the type of shopper that does some research before purchasing or are you the type that just goes with your gut? In this computer age, product research is getting easier even for those that tend to leave things to chance. It seems like every major online store has costumer reviews for each product, but this type of information is not so readily available for medical products. So what do you do now that you have been told that you need a new knee? You could just be lead like a lamb to the operating room or you could really put some brain synapses together to come up with a plan that is right for you.

First, you'll want to research the surgeons in your area. Insurance constraints might limit your choices just a bit. To start, ask for your plan's list of orthopedic surgeons in your area. Go down the list to see if you recognize any names. Some friends, family members or other professionals might have mentioned a name or two to you in the past. If you don't recognize any names, ask around. Next, you'll want to look at the surgeons resume. Don't be shy; many good doctors post their Curriculum Vitaes online. You could look at clinic websites for the individual doctors but those websites can be full of misleading information -- this is a business and money is to be made. And you may need to work backwards by choosing which knee implant you would like first and then finding a doctor who is most familiar with the product.

Once you have found the right surgeon for you, you'll want to have some general knowledge about the available knee implants. Here is a list of terms that you will come across:

Non-constrained Knee: This knee is appropriate for someone who has good ligaments that will support the new knee.

Semi-Constrained Knee: People without a really good ligamentous support system need some built in support from this type of knee

Constrained Knee: Rarely used, this knee offers full, built-in stability; no ligaments required.

Mobile Platform: This newer type of knee implant offers more mobility and possibly a longer device lifespan for those who are really active or younger.

Fixed Platform: This type of knee implant is more appropriate for older, less active knee

High Flexion: People who kneel a lot or need a fully bending knee might want to consider this type of knee implant.

Cemented: The implant is fully cemented into place for a fast bond.

Cement-less: This implant relies on bone growth into the implant for adherence of the implant to the bone.

Hybrid: Part of this implant is part cemented and part of it is left for the bone to grow into it.

Now that you are primed with the lingo, it's time to shop for a specific knee implant. You'll see some ads on television and other media, but you'll need to dig deep to get the real story about each of these knee implant manufacturers.

Styker: The "Get Around Knee" is the implant that they are really marketing lately. According to them, this knee allows for more natural movement. Well, that may be so but does it really improve your ability to do things or get around better than another knee implant? Probably not; what you really want to know about implants is the revision rate. How often and how soon does that implant fail enough to require a second operation? Styker has a recent recall on a hip implant because of its high revision rate. Their knee implant does not have the same problems because it is not a metal-on-metal device. But, this 2012 recall does leave one to wonder about the types of implants that Styker is marketing.

Zimmer: The NexGen High Flex knee looks real tempting, but the recent scandal between a former Zimmer consulting surgeon and the company leaves a bad feeling about the company's integrity. In question is the Zimmer hip implant revision rate, which some say is due to a product defect and should be grounds for a recall. Of course, the company is blaming the surgeons.  Although this involves a hip implant and not a knee implant, the fact that Zimmer is not voluntarily recalling its hip implant when there is some doubt leaves one to question whether or not this company deserves your business.

DePuy: The LCS Complete Knee System is this company's flagship knee implant. Unlike Zimmer, this company did choose to voluntarily recall its hip implant when it came into question regarding revision rates. The LCS Knee system has been utilized since the late '70s and has a proven track record. As technology progressed, so too did this product. The updated version offers high flexion and mobile platform options. DePuy is looking pretty good in the knee implant market.

Your shopping research is not quite over yet. There is a new knee implant technology creeping into the market place. These knees are called the "Custom Knees" which use 3D technology to image your existing knee and utilize a computer to create custom templates for cutting and designing your new knee. Watch out for this hype because these custom knee implants have not been proven to be more effective than traditional knee implants and they come at a great expense.1,2,3

Now that you have fully researched this topic, you are ready to "purchase" your new knee. No matter what your choice is, you will be more likely to be a satisfied customer if you have done your homework and have done everything possible to go into surgery with confidence and good health. Enjoy your new knee.

  1. Clin Orthop Relat Res. 2012 Mar;470(3):889-94
  2. J Arthroplasty. 2012 Feb;27(2):180-5
  3. Orthopedics. 2010 Aug;33(8):569-76