FAQs after Knee Replacement Surgery

Total Knee Replacements are very successful procedures with very good outcomes improving a patients quality of life and most importantly getting rid of the arthritic pain. For the past 5 -10 years, studies have usually recorded 95% good to excellent results.

More recently, the longevity of total knee joint replacements have increased. In some cases it will outlast the persons life span.

This arthritic pain pretty much disappears immediately after the operation.

Our patients walk 3-4 hours after surgery and can put all the weight through that leg.

Swelling & Bruising?: extensive swelling & bruising can be found in some patients. Sometimes from the thigh down to the foot. At times the bruising can be quite dramatic, but it will resolve with time and can take some weeks to occasionally months.

Can I do anything to improve the swelling and bruising?

Generally, the more active patients have less swelling and bruising, because of improved muscle function. You may expect the swelling to last 3-12 months or so, and during this period it will gradually diminish rapidly. Walking and gentle exercise will help. The bruising, which may look dramatic, but is of no clinical importance, will not last as long. It is the result of blood at the sight of the operation oozing through the tissues. This will resolve over a period of weeks. Gentle activity will also help that to dissipate.

Will this metal prosthesis set off Alarms in the airport?

Probably yes. This is a metal implant, of reasonable size, and is likely to be picked up by the metal detectors. It is a nuisance, but no documentation, such as ID cards, letters, x-rays, etc, will help the passage through customs, because these are easily forged. Probably the best approach at the airport, is patience.

Pain?: The arthritis pain would have disappeared. Our Rapid recovery programme with Local Infiltration analgesia means you should be comfortable and mobilizing few hours after surgery.

It has to be understood that in a total joint replacement, it takes atleast 12 months to realize the benefits.

Skin Blisters: in some instances blisters will develop near the operation, and possibly above it. This is due to surface fluid. It can look dramatic, but it is of no consequence, and always resolves. Sometimes it maybe due to the bandage rubbing on the skin.

We change the bandage after about a week, but would prefer not to interfere with that earlier, because of the risk of infection

Another cause for the blistering is tissue swelling.

They may burst, and leakage of fluid, and again we leave the dressings well alone and not disturb it.

Muscle soreness: after surgery, muscles can feel stiff and sore to touch.

The tourniquet is usually used during the performance of a knee replacement for a short time

However, the pressure of the tourniquet on the muscles, causes discomfort, which may last for several weeks. The discomfort, always resolves and active mobility, walking, stretching, physiotherapy, etc, will help to speed the result.

Warm feeling around the knee: the operated site may feel hot and the heat may last 3-12 months. As part of the healing process, the operation site requires more blood supply from the body, and it is this extra blood supply which gives rise to the local heat.

Mobilizing:

Activities are usually limited the first 2weeks, however, you will be able to walk independently, use the bathroom and perform normal activities of daily living.

After 4-6 weeks you will be able to engage in moderate activities, i.e. driving a car and climbing stairs.

Within 6-8 weeks you will have resumed most of your normal activities. Complete surgical healing takes 12 – 24 weeks. During this time some swelling and discomfort is normal, and should be manageable with the prescribed medication.

Physiotherapy

Exercises help strengthen the muscles around the new knee and improve the range of knee movement. The physiotherapist helps you start walking, a few steps at a time, to promote healing.

As you progress from crutches, and then a cane, you may feel somewhat off balance at first. Gait training helps you regain confidence and your normal walking motion before going home.

Am I likely to have manipulation if the knee joint replacement is stiff?

It is possible that a manipulation may be required. If the range of knee flexion has not reached 90°, by six weeks, then probably we should consider a manipulation of the knee. 90° is important, because it allows you to get up from the chair and the toilet with relative ease. The manipulation is usually coordinated with physiotherapy so best results are achieved.

Driving?

This is an individual matter, and depends on how well one is to progress. Some people regained their coordination and reflex is more quickly and others take longer. Some people need pain killers for longer than others. Generally, people take three weeks or so to be able to drive, but this varies enormously.

When can I do stairs?

When in hospital, the Physio will take you up and down stairs, to ensure that this is an activity that you can undertake. Generally, it is the physiotherapist, who will help you with this.

Shoes?

High-heeled shoes should be avoided for at least three months. You should wear comfortable shoes. Try and avoid shoes with soles that will slip.

Heating pad or ice packs?

Both ice and heat can be used to relieve pain at the operation site, but both can be harmful if left on too long. Never sleep with a heating pad on your knee. It can damage the skin and cause burning. Ice packs can be used several times a day, 20 minutes on and 20 minutes off.

medications after surgery?

This will be discussed by the anaesthetist depending on your medical problems. It is important to follow his or her instructions.

Problems sleeping at night?

A very common question. A knee replacement is a major surgical procedure. It is preceded by a certain amount of anxiety, and after surgery, there is normally a significant amount of stress relating to pain, healing, progress, etc. This will certainly improve with time We have an excellent team to look after you and you are in good hands.

What are the best positions for sleep?

You can sleep in any position in which you are comfortable. The sleeping position will not affect knee function, or the operation site.

Wearing stockings?

We recommend stockings to be worn atleast for 3 weeks after surgery, this helps with the swelling.

Failure or revision surgery:

The prosthetic knee can wear out or loosen and may require replacement if necessary. On the other hand, people live longer now, and you may out-live your new knee. Regular review is recommended.

Risks of having any Total Knee Replacement

Infection

Infection is uncommon occurring in less than 2% of cases.

It is usual for each patient to be is given intravenous antibiotics at the time of their joint surgery and after wards.

Infection in the post-operative period in most patients is treatable. Patients may be treated with antibiotics for a longer period than normal and wash out of the joint will be required.

In some cases, the implant will be removed to treat the infection before reimplanting a new joint ether as stage 1 (new implants put in the 1st time with antibiotics in the joint) or 2 stage procedure where patients may have a cement spacer for a short period (6-12 weeks) before the definitive procedure.

Infection is uncommon and we take detailed precautions to avoid this problem.

Blood Clots (deep vein thrombosis, pulmonary embolism)

Another risk is blood clots after a joint replacement.

Since our patients are mobilized very soon after surgery, this risk is small.

Calf compressors during and after surgery also help.

After surgery "TED stockings" and low doses of aspirin or other anticoagulation (blood thinner) medications are prescribed depending on the patient’s medical history.

In patients without any history of thromboembolic (blood clot) problems, we advise taking aspirin, 300 mg per day, for a period of six weeks. This is normal aspirin, and if you take low dose aspirin, such as Cartia, which is 100 mg per tablet, three of these need to be taken per day.

These measures are in place to reduce the risk of forming a clot.

In the event the patient is diagnosed with a blood clot, intravenous or subcutaneous anticoagulation therapy may be required.

There is no perfect treatment, and while trying to decrease the significant risk of deep vein thrombosis and the possibility of more serious complications, such as pulmonary embolism (blood clots breaking off and traveling to the lungs), other potential side effects (such as bleeding) can occur with the drugs used to decrease this complication. These medications require extreme care in their use.

Prosthetic Loosening

Loosening or excessive wear of the components (plastic, metal and cement fatigue) is another complication of joint surgery. Loosening can occur in one or all component.

Running and jumping should be avoided and care taken to avoid weight gain. The potential risk is approximately 1% per year. This means, it is a gradual process, characterised by increasing discomfort. In most cases if the components become loose, it can be corrected by another surgical procedure, replacing the worn or loose component.

Stiffness in the Knee

A decrease in motion of a joint is also a potential risk. The joint condition prior to surgery will have some bearing on the movement post surgery. Physiotherapy and exercise are encouraged prior to surgery. Post surgery, if the joint remains stiff, physiotherapy or manipulation can improve the range of motion in the joint.

Dislocation

Dislocation of components is a possible risk of knee joint replacements. It is very rare, approximately less than 1% of components dislocate in the immediate post-operative period.

In the vast majority of these cases treatment of this problem requires manipulation of the joint. If unsuccessful in relocating the prosthesis, a second open surgical procedure may be necessary to fix the problem.

Nerve Damage

Nerves (usually under the skin) can be traumatised at the time of the operation through stretching and occasionally due to swelling after surgery. We take every precautions to protect the nerves during surgery. If nerve damage occurs – rest and further examination of the nerve will be required, and possible further surgery.

Other Complications

Other complications that can occur include, instrument failure, muscle wasting, artery or vein trauma, drug reactions, instrument or implant breakage and loss of income. These complications are rare. It is important to be aware of complications when considering joint surgery.

Useful Links