Knee Replacement: What to Expect

Preparing for Knee Replacement Surgery – What Should You Expect?

Pre-admission Testing

Within 1 month of your surgery, you will be asked to undergo several laboratory tests, an electrocardiogram, and chest x-ray. This is called pre-admission testing. This will help us to tell whether there are any conditions which might increase the risk of surgery. A physical examination, performed by your primary care physician and cardiology/pulmonology (if necessary), is also a part of pre-admission testing.

Joint Class

All patients should attend joint class prior to their surgery. This will be arranged by your surgical coordinator and plays a very important role in your surgical preparation. Patients who attend this class have demonstrated a more predictable and successful recovery.

Just Before Surgery

You will be asked to arrive 1.5-2 hours prior to your scheduled surgery time.

You will not be allowed to drink or eat anything after midnight and on the day of your surgery. In some cases, you may be allowed to take a medication you normally take in the morning with a minimal amount of water. If instructed to do so, you will need to let the admitting nurse know that you have done this.


You will be seen by the anesthesiologist on the day of surgery. The anesthesiologist can answer specific questions you might have. Most of our surgeries are performed under spinal anesthesia, though we will also use regional and general anesthesia when a spinal does not seem to be the best option.

You may receive some medications in the holding area prior to your surgery. These may include  specific pain medications and antibiotics for your surgery.

The Surgery

As stated before, the surgery involves the removal of all of the damaged bone and cartilage. This is done with saws and drills much like a carpenter uses. The next step is to prepare the bone for the prosthesis. This involves using specialized tools to make precise cuts and to shape the bone so that the prosthesis will fit properly. The artificial joint is then placed into the bone with or without bone cement. The surgery itself takes between 2-3 hours, depending on the complexity of your case.

Total knee prostheses can be attached to the bone using a material called methylmethacrylate or, more simply, bone cement. With proper technique,this gives an immediate fixation of the prosthesis to the bone. Another method is called biologic fixation. This method uses no cement and with time, bone grows into the pores of the prosthesis. This is similar to how most hip replacements are fixed to the bone. There are advantages and disadvantages to each type of “fixation.” The type recommended to you will depend on your age, weight, activity level, and surgeon preference.

Recovery Room

When your surgery is completed, you will go to the recovery room where you will be closely monitored until the effects of the anesthesia and intra-operative medicines are decreased and you are relatively awake and comfortable.

Orthopedic Unit

When you have completed your stay in the recovery room, you will be transferred to your hospital room in the orthopaedic nursing unit. As long as you feel well, you will be out of bed on your day of surgery, hopefully taking your first steps!. The therapists will instruct you in learning how to use crutches or a walker and being taught some of the precautions that are necessary in the immediate post-operative period. Our therapists are extremely good and will help you navigate these first challenging days.


Most patients will be able to go home 1-2 days after surgery. Some will stay for a 3rd day and others may go to a short-term rehab facility to help improve strength and gait. In order to leave the hospital, you need to be safe moving out of your bed/chair, have pain controlled by medications you can take at home, and able to tolerate a diet.