Knee replacement surgery
Total knee replacement (TKR) is used to replace the joint between the femur and the tibia when it is damaged by osteoarthritis, meaning when there is deterioration of the cartilage.
Osteoarthritis is most often idiopathic, meaning it is due to wear and tear, but it can also be secondary to:
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a fracture (this is referred to as post-traumatic osteoarthritis),
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arthritis related to an inflammatory disease or an infection,
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osteonecrosis of the femur or tibia,
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chronic instability.
What is a total knee replacement (TKR) ?
Total knee replacement (TKR) consists of:
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a femoral implant,
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a tibial implant,
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a polyethylene insert that replaces the cartilage and serves as the bearing surface against the femoral implant,
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sometimes a patellar implant (“button”) made of polyethylene, which replaces and resurfaces the kneecap; it is reserved for specific cases (such as rheumatoid arthritis).
The lifespan is over 15 years in 90% of cases.
What happens during the surgery ?
After blood tests, a cardiac evaluation, and an anesthesia consult, the procedure is most often performed under general anesthesia and lasts about one hour. It can also be carried out under spinal anesthesia. The anesthesiologist will decide with you on the most appropriate option.
An incision is made on the front (anterior) part of the knee, allowing access to the joint while minimizing trauma to the muscles and tendons.
Local anesthetic injected in the soft tissue around the joint, significantly reduces post-operative pain and helps limit the need for pain medication.
And after the surgery ?
After surgery, patients can walk the same day with full weight-bearing. A pair of crutches is used initially for safety.
Hospital stay usually lasts between 2 and 4 nights to begin rehabilitation and effectively manage post-operative pain.
After the surgery, wound care is required for about two weeks, and anticoagulant medication must be taken for 5 weeks to prevent blood clots (deep vein thrombosis).
Rehabilitation is essential afterward. It can be done at home or in a rehabilitation center and helps restore knee mobility as quickly as possible while minimizing the risk of post-operative stiffness.
What are the risks ?
Like any surgical procedure, total knee replacement carries risks:
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the most serious, though fortunately rare (less than 1%), is infection, which often requires additional surgery and prolonged antibiotic treatment. The risk is higher in active smokers,
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knee stiffness may occur if post-operative rehabilitation is insufficient.
An incision is made at the front of the knee, allowing access while minimizing damage to the muscles and tendons.
Local anesthetic infiltration helps significantly reduce post-operative pain and limits the need for pain medications.
And partial knee replacement ?
90% of patients achieve good results after the procedure.
The knee is divided into three compartments: the medial femorotibial compartment, the lateral femorotibial compartment, and the patellofemoral joint (between the femur and the kneecap).
In some cases, osteoarthritis affects only one part of the knee—either the medial or the lateral compartment. In such cases, a unicompartmental prosthesis can be used to replace only the damaged compartment.
The advantage is a less invasive procedure, with less bone resection and faster recovery. However, this option is only possible if all the ligaments around and within the knee are functional.