Total Knee Replacement

Arthritis is a common diagnosis in the knee joint that involves destruction of the cartilage, or the smooth surface that covers joints. The most common type of arthritis experienced by patients in the knee is osteoarthritis, or “wear and tear” arthritis. There are other types of arthritis that can degrade cartilage including inflammatory conditions such as rheumatoid arthritis or post-injury joint damage such as ligament injuries and fractures. Degeneration of the joint surface often leads to pain, stiffness, deformity and loss of function.

 

Diagnosis of knee arthritis can be made through consultation with a physician and regular X-rays. More sophisticated imaging such as MRI scans are not often required, and arthritis that is only seen on an MRI scan is not severe enough to warrant surgery. Furthermore, whether or not you have a recent MRI scan will not affect our ability to give you good advice on the severity of your knee arthritis and will not expedite surgical decision making.

Osteoarthritis Knee ( OA Knee ). Film x-ray both knee ( front view ) show narrow joint space ( joint cartilage loss ) , osteophyte , subchondral sclerosis

The treatment of knee arthritis begins with optimization of non-operative treatment measures including alteration of activities, exercise-based physical therapy, such as GLAD exercises, braces, walking aids such as a cane or walking poles, non-opiate pain medications, or injections. If non-operative treatment measures are unsuccessful, surgical management including total or partial knee replacement can be considered. Although arthritis often results in stiffness and deformity, the main reason for requiring knee replacement is pain that interferes with the quality of life of the patient.

At the VHKRI we are happy to discuss our experience with intra-articular injections. Our surgeons will discuss injections into the knee joint of either cortisone or a gel (viscosupplementation) in certain scenarios. We do not perform platelet rich plasma (PRP) injections. Stem cell injections have no proven benefit and are not allowed by Health Canada.

Knee replacement surgery is when the diseased articular cartilage from the tibia (or shin bone) and femur (or thigh bone) are removed and replaced with artificial components. Knee replacements are typically made of metal (titanium and cobalt chrome alloy) as well as a plastic liner. If necessary, the back of the patella (or knee cap) is replaced with a plastic component. The components are either cemented or uncemented. Partial joint replacements can be considered in specific forms of arthritis.

Knee replacements are referred to as partial or total. Total knee replacements involve replacement of the complete knee joint surfaces of the tibia (or shin bone) and femur (or thigh bone). The kneecap is only resurfaced when necessary.
Partial knee replacements are where only part of the knee joint is replaced. The knee is divided into compartments including the “medial” or inner part of your knee, the “lateral” or outer part of your knee and the patellofemoral compartment where the kneecap glides on the thigh bone. Partial or unicondylar knee replacements are when only one compartment of tibia and femur, most commonly medial, are replaced. Patellofemoral knee replacements are when the kneecap and where it glides are the only components replaced. Partial knee replacements are only options for patients with specific types of arthritis. At the time of your consultation your VHKRI surgeon will advise you whether you are a candidate for partial knee replacement. Most patients seen in our clinic will have numerous regions of the knee affected by degenerative arthritis. Therefore, most patients will receive total knee replacement rather than partial replacement. It is well established that partial knee replacements have a higher risk of needing revision surgery in the first 10-20 years and generally do not permit a higher level of participation in sports or other aspects of an active occupation or lifestyle.
All partial knee replacements at the VHKRI are performed by Dr. Bas Masri.

In some cases, bilateral knee replacement may be an option. This discussion involves several factors to determine if it is a good option for you. Your hospital stay is often longer, but the same amount of rehabilitation is required. If both knees hurt and are equally bad, you may be a candidate for bilateral knee replacement surgery.

Some people with previous knee replacements require another surgery due to complications such as infection, fracture, loosening, instability, or the joint has worn out or there is bone loss. The VHKRI has extensive experience in revision knee surgery.

Knee replacements are considered in patients with pain in their knee joint due to arthritis that has not responded to nonoperative options and causes disturbance to their quality of life. While a knee replacement can restore some elements of function, they are not designed to allow you to return to some sports such as running and jumping as those activities may cause pain. While there are no imposed restrictions, certain activities may not be possible. Most patients also report problems with kneeling, so activities that require kneeling may need a kneeling pad. Athletic individuals should understand that knee replacement may not restore high intensity activities to their liking. We encourage you to discuss your goals for returning to sports, or demanding activities, at the time of your consultation so we can help you determine realistic expectations based on best-available evidence.

Important points for knee replacement surgery

  • Aggressive early exercise-based physiotherapy is required to regain range of motion
  • Recovery can take up to 1 year
  • If your knee is very stiff before surgery, you will always have an element of stiffness after knee replacement. Do not expect a full range of motion after surgery.
  • There are no restrictions to kneeling, but it may hurt. Be prepared to use a kneeling pad if necessary. Kneeling will not hurt the joint.
  • Most knee replacements will last 20-25 years if there are no complications. The chance of needing a second operation at 15 years is only 10%.
  • Numbness to the outside of the knee is normal and expected.
  • Noises and clunking are also normal as the inner surface of the knee will now have metal against plastic at the joint surface rather than the previous meniscus tissue or “shock-absorber” cartilage that you were used to having prior to the joint replacement.
  • Research shows that up to 20% of patients after a knee replacement can still have pain or are unsatisfied after their knee replacement. It is very important to meet with your VHKRI surgeon to discuss and establish realistic expectations for your post-surgical outcome well in advance of surgery. Many of the patients who report dissatisfaction with their knee replacement had expectations for the new knee that were not realistic or attainable. For most patients, a knee replacement surgery will provide them with a meaningful and noticeable incremental improvement in their quality of life, function and pain.
  • Some ongoing symptoms such as sense of warmth, occasional swelling, throbbing, or night pain can persist for several months after a knee replacement. In most cases this will settle down and should not prevent you from experiencing a very good outcome.

Although 80% of patients are satisfied with their knee replacement complications can occur on occasion. These may include, but are not limited to, medical complications such as heart attacks, strokes or blood clots or surgical complications such as infection, bleeding, nerve injury, dislocation, fracture, loosening and stiffness. Up to 20% of patients after knee replacement can have persistent pain, though most are still improved from their preoperative pain level. It is important to discuss these risks with your surgeon prior to proceeding.