All you need to know about knee replacement surgery

Knee replacement surgery, also known as a knee arthroplasty, is recommended when reduced mobility caused by knee joint damage begins to hinder day-to-day life, or if knee pain is causing extreme discomfort even during periods of rest.

When is knee replacement surgery necessary?

Knee replacement surgery may be necessary in patients who have arthritis, and for whom conservative treatments such as physiotherapy, pain killers, and, in some cases, arthroscopies, have failed. Other reasons for knee replacement surgery include: abnormal bone growth, knee injuries, and haemophilia.

What does knee replacement surgery involve?

In order to carry out a knee arthroplasty, the patient must first be put under general or spinal anaesthetic. The surgeon makes an incision in order to expose the knee joint, then using specially designed jigs fitted on the femur and the top of the tibia, a gap is made where the knee prosthesis is placed.

Knee replacement surgery generally takes about an hour to perform. Afterwards, the patient will remain in hospital for three days under observation until they are ready to go home.

Using minimally invasive techniques when performing a knee arthroplasty has a number of short and medium term benefits including minimised scarring, less pain, and a faster return to mobility. Long term results have proven to be the same.

How long is the recovery time after knee replacement surgery?

It usually takes around 3 months for the patient to be able to return to a reasonable level of activity after a knee replacement, and 6 months before they can completely return to life as normal. This may vary depending on the individual. Age, weight, and fitness can all play a role in how fast a patient recovers after a knee replacement operation.

Are there any risks?

As with any general anaesthetic, there is always the risk of heart attack. Other main knee replacement surgery risks include: wound infection, deep vein thrombosis, and nerve injury. These generally occur in a small minority of cases.

Choosing an experienced specialist to carry out knee replacement surgery greatly improves the success rate post-operation.

How will patient specific instruments change knee surgery in the future?

Using patient specific instruments greatly improves accuracy during knee replacement surgery. In the short term their use decreases surgery time by around 20 minutes. They also allow for a much less invasive surgery, as there is no longer the need for the surgeon to insert a big rod into the femur in order to implant the jigs, thus decreasing the risk of fat embolism and other complications.

One downside is the waiting time of 6 weeks after seeing the patient whilst the instruments are manufactured.