Your Guide to Knee Replacement: a “Q&A” with Dr. Matsen Ko

Your Guide to Knee Replacement: a “Q&A” with Dr. Matsen Ko

I would like to share with you some answers for questions I commonly receive from individuals with knee arthritis. You may have additional questions and I’d be pleased to try to answer them for you as well.

What is the right time to have a knee replacement?

Knee replacement surgery is considered when your knee arthritis pain and stiffness keeps you from performing the activities you enjoy (such as walking up and down stairs, golfing, hiking, walking, working out, dancing).

Common movements that may increase your arthritis knee pain

Going up or down stairsGetting up/ down from chairBending your knee makes it ache on the inside/ outside or frontAching in knee after prolonged time standing or walking on harder surfaces (trips to Costco, walks on city sidewalks)

Other signs your knee pain is from arthritis

You may notice some knee swelling and a decrease in your ability to fully straighten your knee or bend your knee as much as you used to.Your leg may have become more knock-kneed or bow legged

Because knee replacement is an elective procedure, you should be in your best state of health and fitness before proceeding – optimal health makes the surgery safer and speeds recovery.

Why did you get knee arthritis?

Knee arthritis is usually from a combination of both genetic and environmental factors. Some of my patients report that their sister, aunt and grandfather all have arthritis. Other patients report that they had a prior injury and have had knee pain since. Your knee pain and stiffness result from a degenerative process in which your joint has lost its normal smooth cartilage, so that now you have pain from the irregular surface of your bones rubbing on each other.If you’ve had prior knee surgery, there is a chance some of the meniscus (or cushion) of your knee needed to be removed. This may cause an acceleration of time in which surgery is required or suggested.

What can you do to optimize the chances of a good outcome?

Visit your primary care physician to ensure you are in the best possible health. I am reluctant to perform elective surgery on individuals who are significantly overweight, those who are smoking and those who are on major narcotic medication because these factors interfere with a smooth and safe recovery. I work with my patients individually to get them into healthy habits that will ensure their success and give them the best life post-surgery! Optimize your fitness. Get some aerobic exercise every day, choosing activities that are comfortable for you: water exercises, elliptical, stationary cycling, and upper body workouts. Make sure you have a good plan for support when you leave the hospital (for example, who will keep an eye on you and help you get around?)

How long does the surgery take?

The actual surgery takes around an hour and a half. You will be in the surgical suite a bit longer while the anesthesiologist cares for you before and after the procedure. After surgery, you will spend around an hour or so in the recovery room. When you are ready, the nurse will invite a family member or friend back to see you.

What happens in total knee replacement surgery? The arthritic areas of your joint are removed: the end of your femur and top of your tibia are shaved down to accept the implants that are cemented into your bone.

How will your wound be closed?

I nearly always close my wounds with stitches under the skin and then glue on top. No stitches or staples need to be removed.You will have a waterproof dressing on top of your wound that will allow you to shower after your surgery.

How many nights will you spend in the hospital?My total knee patients generally spend 1 night in the hospital and then are fit to go home with a friend or family member.

What is recovery like?

My goal is to help you get up and around as quickly as we can after surgery and to minimize the need for pain medications that could slow your progress. I find that the sooner patients are on their feet, the better they feel.While in the hospital, a physical therapist will help you get up a few hours after surgery. You will be allowed to bear full weight on your leg in walking, but may use a cane, crutches or walker for balance until you are steady on your feet. You will be taught to climb stairs prior to leaving the hospital.It is important that you continue your exercises once you leave the hospital. Exercises during first six weeks after surgery are key in regaining your full knee range of motion and avoiding stiffness.My patients often use a cane or walker for the first 4 weeks and are back to gentle exercising by 2 weeks (walking and gentle spinning on a stationary cycle). You will progress your activity as your comfort allows. At one to three months after surgery, my patients generally start activities such as elliptical, easy golf, gentle yoga, longer walks and swimming, .

When will you be able to return to work?Desk workers usually return to work around two weeks. More active occupations may require a bit more time for recovery. I will work with you individually to set expectations for your timeline.

When can you drive?Most patients feel comfortable driving around three to four weeks after surgery. You should not be taking any narcotic pain medicines if you are going to drive. First try your driving in an empty lot or on a quiet road to ensure you feel physically and mentally up to driving.

What are the risks of surgery?

Healthy patients have less than a 1% risk of major complications. The risk is increased if the patient is not in good health – in such cases I work with my medical colleagues to develop a plan for minimizing the risk before surgery.According to the published literature, the two most common complications of knee replacement are infection (sometimes requiring further surgery) and blood clots (usually treated with strong blood thinners such as Coumadin). I minimize the risk of infection with prophylactic antibiotics and careful surgical technique. I minimize the chances of blood clots by encouraging circulating-stimulating activity immediately after surgery and by using blood thinners when there is an increased risk.There are also risks of instability, dislocation, implant loosening and wear, but these are very low in my experience.

How long will my new knee last?

The track record with the implants I use is excellent.At 15 years, at least 90% of patients are happy with their knee and have not required a revision procedure.

These are my answers to commonly asked questions. Feel free to make an appointment and I can answer any further questions you may have!


Dr. Laura Matsen Ko

Joint Replacement Surgeon

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