Total knee replacement – what you can expect in three months?

This is the concluding part of a two part-article on complete knee replacement. The first part has details about the different types of replacement, diagnostics, and anesthesia.

Pre-operative preparation of a patient for total knee replacement includes stopping food intake after dinner on the night preceding the procedure. The patient is to take adequate rest and use prescribed antibacterial soap on the night before the procedure and on the day of the procedure. Read on to learn more about perioperative care of patient before during and after the procedure.

What happens during a total knee replacement procedure?

Post anesthesia, the patient will receive fluid management through an intravenous line. During the procedure, the patient may also be on a urinary catheter, though it is not necessary in all cases. It was the standard practice earlier to use a Foleys Catheter, though it has been dispensed with and is not mandatory always. Next, the patient will undergo preoperative hair removal, which could be either through shaving or clipping or by using depilatory creams. This is never performed in the operation theater, but in a separate room to avoid contamination of the sterile environment. The hair removal is performed by trained personnel, to prevent surgical site infections and periprosthetic joint infections. It is to bear in mind that hair removal is necessary only when the hair is likely to affect the procedure.

Throughout the procedure and during the recovery phase, the anesthesiologist will continuously monitor the vitals of the patient once anesthesia is given to the patient. As mentioned in the first part, the type of anesthesia is determined by the specialist based on various factors. Vitals that are monitored during the procedure and during the recovery phase include heart rate, blood pressure levels, and oxygen in the blood among others.

Components of a prosthesis

The prosthesis comprises a tibial component, a femoral component, and a patellar component. The tibial component is for the purpose of resurfacing the top of the tibia, the femoral component is for the purpose of resurfacing the thighbone end, while the patellar component is for resurfacing the kneecap bottom that is in contact with the thighbone)

Different stages or actions during the procedure

After the surgeon makes an incision in the knee area, the procedure typically comprises four different actions or stages – preparation of the bone, positioning of the implants, resurfacing of the patella and insertion of the spacer.

• Preparation of the bone involves removal of damaged cartilage, and a very small portion of the bone. The ends of the femur and the tibia are likely to have damaged cartilage and this is removed. Once this is completed, the knee is ready to receive implants that could be made from either metal alloys, plastics of very high grade and polymers.
• The positioning of the implants is performed to replace the removed cartilage and bone. The purpose is to recreate the joint surface with artificial components. Depending on the condition of the surrounding bone, the artificial implants may either be pressed into position to fit snugly, or may be cemented in place. Cemented prosthesis is more common and uncemented prosthesis are hardly used in procedures. In prosthesis that are not cemented, the bone grows and attaches to the porous surface of the prosthesis, whereas in the cemented types, the surgical cement affixes the prosthesis in place.
• The next stage is the resurfacing of the patella. This part of the procedure is not mandatory in all cases, and depends entirely on the condition. Surgeons will decide if the patella needs to be resurfaced. This involves cutting and resurfacing the kneecap with plastic.
• Finally, a spacer is inserted between the metal components to replicate the smooth gliding action of the knees. This spacer is made from high grade plastic and helps the individual’s mobility without any discomfort.

Post-procedure actions at the operation theater

The conclusion of the procedure involves attaching a drain for removal of fluids from the site of surgery, following which the incision is closed. This could be either with staples or stitches, and after the incision has been closed, a sterile bandage is applied on the site.

Recovery room procedure

On conclusion of procedures at the operation theater, the patient is moved to the PACU, acronym for Post Anesthesia Care Unit. This is the recovery room, which is also a critical care unit, where the vitals of the patient are monitored closely. This includes monitoring of blood pressure, breathing, pulse and oxygen level in the blood. As the patient recovers from the effects of anesthesia, pain management commences, in addition to administering fluids. The time required for a patient to recover in a PACU may be around 1.5 hours, depending on the condition.

Post operative stay in hospital

Post recovery in the PACU, the patient is typically expected to remain in the hospital anywhere between two to five days. During the stay in the hospital, a therapist works with the patient to put in place an exercise plan, as it is essential to move the new joint. This may involve the use of a machine that helps the patient with specific knee movements, along with pain management. The therapist also explains the range of movements and actions that need to be practiced at home after discharge from hospital.

Post discharge from hospital

After the patient is discharged from hospital, the site of surgery is to be kept clean and dry always to prevent any possible infections. Medications or managing pain will be prescribed, while the patient will also be advised about the right posture to be adopted to prevent or manage swelling at the site of procedure. In the event the stitches are of the non-dissolving type, it will be typically removed around two weeks after the surgery, during a follow up visit to the hospital. Procedures that involve the use of dissolving stitches or surgical staples will not require removal.

Mobility of patient knee during rehabilitation

The patient will be in a position to bend knees to 90 degrees, two weeks after the procedure, and with the right exercises, this will improve to 100 degrees in three weeks. The final phase of rehabilitation will let the patient to move about independently, giving the patient the ability to achieve full functional mobility, without the need for any device or walker. During this period, pain will also reduce gradually, helping the patient achieve mobility without discomfort.