Knee Replacement 101

Knee Replacement 101

Has your doctor told you that you are a candidate for knee surgery? If so, you probably have a lot of questions. Understandably so! When you need to get any kind of surgery, it is important to have a good understanding of what the surgery entails, its potential risks, who needs it, and what you can expect while you recover. Below, learn the key aspects you need to know about getting a knee replacement, so you can feel confident in your decision to have surgery.

What is total knee replacement?

Essentially, knee replacement surgery is exactly what it sounds like — a surgery during which your knee joint is removed and replaced with man-made parts. When you experience chronic knee pain due to arthritis or injury, having a total knee replacement can help improve your quality of life by:

  • Increasing range of movement in the knee
  • Relieving your joint pain
  • Restoring your mobility
  • Improving your ability to complete daily living activities (like climbing stairs or taking a shower)

Total knee replacement surgeries are very common — as of 2010, almost 700,000 knee replacements were performed annually, with this number expected to be in the millions by 2030. Thankfully, this means that orthopedic surgeons are skilled at performing the surgery, which can improve success rates by a lot (more on that below).

How is total knee replacement done?

Total knee replacements usually take between 1 and 2 hours, as long as there are no complications. During a total knee replacement, also called total knee arthroplasty, your surgeon will make an incision across the front of your knee. Your kneecap (or patella) will be rotated so your surgeon can see the area they will be operating on.

Before any new parts can be added, your surgeon has to prepare the bone. They do this by removing the damaged cartilage at the ends of your femur and tibia, along with a small amount of underlying bone.

Next, metal implants will be put in place to the ends of your thigh and shin bones. These recreate the surface of the joint, allowing it to function just as a natural knee would. If needed, your surgeon will fit your patella with a plastic piece. Then, they will insert a plastic medical-grade spacer between the metal components. This will create a smooth surface that allows your artificial knee to function like a natural knee.

Finally, the incision will be closed and you will be ready for recovery.

Who performs total knee replacements?

Total knee replacements are typically performed by orthopedic surgeons, though general surgeons can do them, too. When choosing a surgeon, you will want to find one that has experience performing knee replacements. As a general rule of thumb, the more similar surgeries they have done, the higher their success rates.

To learn more about how to choose the right surgeon, check out this helpful guide . When you use the Carrum Health benefit offered by your employer, you will have access to the highest quality surgeons in the country with significant experience performing the surgeries.

What are the potential risks of total knee replacement?

Knee replacement surgeries are very common and very safe. That said, no surgery comes without any risk.

In general, knee replacements are a common, safe surgery. Two of the key factors to look at when determining risk are the mortality rates (how many people died after having the surgery) and readmission rates (how many people had to go back to the hospital after surgery). The surgeons you have access to at Carrum Health perform significantly better:

  • Same-day mortality rate (death on the day of surgery) — 0.001% US average; 0.0% with Carrum Health’s hospitals and surgeon
  • 30-day mortality rate (death within 30 days of surgery) — 0.25% US average; 0.0% with Carrum Health’s hospitals and surgeon
  • 30-day readmission rate — 4.3% US average; 1.7% with Carrum Health’s hospitals and surgeon

The most common reasons patients were readmitted to the hospital after a total knee replacement were:

These numbers do not need to alarm you. There are many factors that affect mortality and readmission rates, a large number of them related to the health of the patient. If you are concerned about how your health could impact your surgery’s safety and effectiveness, bring that up with your surgeon.

Some of the other potential risks of a total knee replacement include:

  • Complications from anesthesia
  • Blood clots
  • Infection
  • Allergy to metal components
  • Bleeding complications
  • Artery damage
  • Nerve damage
  • Loss of motion in the knee
  • Implant failure

Overall, knee surgery is a safe, effective procedure. While it is smart to be aware of potential risks, do not let them deter you from getting a knee replacement if your doctor advises that you should. You should always talk to your doctor if you have any questions before or after your surgery, or if you think something might be wrong.

Who needs a knee replacement?

There are many telling signs that you may be ready for a knee replacement. If you experience any of the following, you should talk to your doctor and get their opinion:

  • Persistent or recurring knee pain
  • You cannot stand on your “problem” leg for longer than a minute
  • Knee pain during and after exercise
  • Your knee becomes stiff after sitting for long periods of time
  • Walking up and down stairs is difficult
  • Your knee is swollen
  • You have decreased mobility due to knee pain
  • Knee pain while sitting or lying still

Once you and your doctor have identified the potential need for a total knee replacement, you will need to meet these guidelines outlined by the National Institutes of Health (NIH) in order to qualify:

  • Joint disease has been identified through an MRI or X-ray
  • Pain caused by the joint disease that affects your ability to walk or care for yourself
  • Unsuccessful attempts at treating the disease with non-surgical methods for a minimum of 3 months

How long will a new knee last?

Total knee replacements last, on average, 20 years — that is a long time! On the other hand, partial knee replacements only last about 10 years, so there is a pretty good chance you will need another surgery at some point.

There are some factors that can impact how long a knee replacement will last:

  • Age — If you are 50 or younger, you will probably need another surgery at some point. This is usually due to being more active than someone older.
  • Weight — If you are overweight or obese, more strain is placed on your joints. To make a knee replacement last longer (and reduce your risk of complications during and after surgery), weight loss is recommended.
  • Other medical issues — One commonly overlooked aspect that determines how long your knee replacement will last is whether you have other procedures (like dental work) that may cause bacteria to get into the knee replacement.

As with most surgeries, comorbidities, or the presence of more than one chronic conditions, can also play a role in your eligibility for joint replacement surgery. For example, if you are obese with a body mass index (BMI) higher than 45, your care team may recommend a weight loss program before you can qualify for a knee replacement. Obesity can negatively affect the success of joint replacements. Other comorbidities that could impact your eligibility for a total knee replacement include:

  • Hypertension
  • Cardiovascular disease
  • Endocrine disease
  • Gastrointestinal disease

Your doctor or a Carrum Health Concierge can help you determine whether you qualify for a knee replacement.

Are there alternatives to a total knee replacement?

The primary alternatives to knee replacement surgery would be pain management and physical therapy. The general requirements for any kind of joint surgery are that you have tried 3 other non-surgical methods before resorting to surgery. However, if you have tried other options and are still in pain, your doctor is right — you most likely need to have your knee replaced.

Strengthening muscles, losing weight, and increasing flexibility can help improve your knee pain and help you prepare for a successful knee surgery and recovery.

Recovering from a knee replacement 

After the surgery, your surgeon will want to monitor you for complications like infections. You will probably spend 1 to 5 days in the hospital, with an average of just under 3 days. With Carrum Health’s hospitals and surgeons, patients spend an average of just 2.2 days in the hospital.

Within 12 to 24 hours of your knee replacement surgery, someone on your care team will help you stand up and walk around for a few minutes. This is done to help prevent blood clots from forming in your leg. You will also be taught several at-home exercises that will help your recovery. You can look forward to physical therapy appointments for several weeks, too.

Your surgeon will follow up with you at different points throughout your recovery, to see if youa are meeting the milestones you set together. These can include things like walking without assistance and walking up and down stairs. Be patient with yourself and those around you as you recover — full recovery can take up to 12 weeks.

Surgery is never fun but the relief you will feel when you can dance, walk, and live the way you once did will be well worth it. If you book your surgery using your Carrum Health benefit, you will have a dedicated Concierge to help you at every step of the way. If you are a candidate for a total knee replacement, your next step is to schedule a free consultation.