Aching knees plague millions of Americans – mostly due to normal wear and tear on the joint that leads to osteoarthritis. Those patients who want to continue living an active lifestyle will often consider a knee replacement surgery – but typically only after they’ve tried all other non-surgical options.
Dr. Curtis Hanson, a board-certified orthopaedic surgeon who is fellowship-trained in knees, helps explain what’s new in knee replacement and answers some common questions about the procedure.
Q: How do I know if I need a knee replacement?
A: Most patients have tried other options before they get to the point of considering a knee replacement. These may include steroid injections, weight loss, bracing, physical therapy and medication therapy for pain. Once these options have been tried without success – patients are often ready to consider surgical options. In simpler terms, if you’re still running several miles a day or playing high-impact sports – you’re probably not there yet.
While I’ve done knee replacements on patients in their 40s (and even 30s!), my average patient is in their late 50s and just wants to be able to live a fuller life than they’re able to do with debilitating knee pain.
Q: How is a knee replacement different today than it was 10 years ago?
A: The greatest advancements we’ve seen are in the recovery process. Due to minimally-invasive techniques, changes in medications, local and regional anesthetics, and improvements in the implants themselves – it’s far easier for patients to get back on their feet (and knees!) more quickly.
What used to require a 3-4 night hospital stay can now be accomplished with just an overnight stay. Many patients even go home the same day.
We’ve learned more about ways to enhance surgical recovery and are implementing many strategies to help patients get back to their normal routines sooner than ever. One of these strategies is known as ‘pre-hab,’ which is physical therapy/rehabilitation that takes place prior to the surgery. It’s designed to help patients build strength and prepare physically for surgery – and those who take this step tend to have a much easier time with recovery.
Q: Let’s talk about implants – there are many types, how can a patient know which option is right for them?
A: In most cases, your surgeon will make a recommendation based on your anatomy, the condition of your knee and other factors, including their personal experience. When it comes to implants, we use a variety of options.
From the standard cement fixation model that’s used in most surgeries to the press-fit model that forms a biological bond with your body, to newer custom implants, a lot of factors go into deciding which device will work best for each patient.
For example, the press-fit models are great for younger patients who have good bone density as they can improve the longevity of the knee replacement. Custom implants are designed specifically for an individual patient based on a CT scan of the knee.
These work well in patients with relatively normal alignment, good motion in the knee, and those with no gross instability of the knee (which may come from prior trauma or ligament injuries). Some patients with custom implants report a more ‘normal’ feel and a greater range of motion.
Q: How do I know if I need a total knee replacement or just a partial replacement?
A: I typically explain it to patients this way – if you have damage/wear in only one area of the knee, a partial replacement is a good option to consider. The analogy that works best is getting new tires on your car – if one tire is flat and the others work fine, you may not need to get four new tires, or in this case – you may not need a total knee replacement.
Patients who get a partial knee replacement typically enjoy a shorter recovery, better functional outcomes and a more ‘normal’ feeling knee. But, if you have significant damage in multiple areas of the knee, it’s best to replace the whole thing. It’s really about picking the right tool for the right patient – and your surgeon should explain your options and the recommendation they believe is best for your body.
Q: How long does a knee replacement last?
A: On average, we tell patients to expect around 20 years from today’s modern implants. In some cases, they’ll last longer and in other cases, they’ll get worn out before then, but 20 years is a reasonable expectation.
Q: What should a patient expect from a knee replacement?
A: The surgery itself only lasts an hour, but most patients will stay overnight. We’ll make sure you’re walking (including getting up and down the steps) before you leave and that your pain is well-controlled.
We see patients back in the office around 2 weeks and 6 weeks after surgery and thereafter to make sure you’re healing properly. I tell most patients they won’t be happy with me until at least the 6-week mark. While they’ll be walking right away after surgery, it’s not usually a comfortable walk.
By the 6-week to 3-month mark, most patients are back to most of their regular activities and feeling good. This is about the time they’re feeling glad they had the surgery. However, they will likely continue to improve for a year or more after surgery.
Q: Are there activities that are off-limits after surgery?
A: The American Academy of Orthopaedic Surgeons has some great recommendations on which activities are recommended versus those that aren’t recommended.
In general terms, I’d say doubles tennis is on the higher end of what knee replacement patients should probably be doing on a regular basis. Running and impact sports like basketball really aren’t ideal. It’s not that you can’t necessarily do them, it’s that doing so comes with a price of greater wear and tear on the implant, so we don’t recommend them.
Cycling, elliptical, swimming are all great activities for someone who’s had a knee replacement.
Q: What can I do to prepare for surgery, and what can I do after to make recovery easier?
A: It’s important for patients to understand and acknowledge that a primary factor in their success is a personal commitment to following their surgeon’s recommendations prior to and after surgery. This may include a suggestion to lose weight, follow an exercise plan, attend physical therapy and in some cases, make other lifestyle modifications such as diet changes and/or quitting smoking.
The surgery is a great tool, but it’s just that. Our patients who have the best outcomes do strength exercises before and after surgery, attend all appointments as scheduled, and in many cases, see a physical therapist on a regular basis during recovery.
All of these will help patients accelerate their recovery and make the most of the surgery.
About Curtis Hanson, MD
Dr. Curtis Hanson specializes in disorders of the knee, including sports injuries, arthritis and trauma. His specialty training includes arthroscopic surgery, joint replacement and limb realignment procedures.