A minimally invasive total knee replacement (TKR) is a procedure to replace the surface of the knee and reconstruct the knee joint. It involves making small cuts with minimal disruption to the surrounding tissue.

A doctor may recommend minimally invasive total knee replacement (TKR) for conditions such as arthritis. The treatment may help reduce pain and improve movement.

Read on to learn more about what minimally invasive TKR involves, when a doctor may recommend it, what the recovery process is like, and more.

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A minimally invasive TKR typically involves a surgeon making small incisions into the skin surrounding the knee, approximately 4 to 6 inches in length. This compares with incisions for traditional knee replacement, which are around 8 to 10 inches.

The surgeon then uses specialist surgical instruments to remove any damaged cartilage and bone at the ends of the thigh (femur) and shin bones (tibia).

The surgeon then replaces the cartilage and bone with two artificial devices, typically comprising metal. This recreates the surface of the joint.

The surgeon may then cut the underneath of the kneecap and replace it with a plastic button.

To complete the minimally invasive TKR, the surgeon inserts a plastic spacer in between the two metal devices to reduce friction.

Learn more about what to expect from total knee replacement.

A doctor may recommend a minimally invasive TKR if a person has any of the following:

  • knee osteoarthritis
  • other types of arthritis
  • injury or damage to the knee
  • significant knee pain that does not respond to other treatments
  • issue with the knee joint not forming correctly

Minimally invasive TKR can benefit conditions that cause the breakdown of cartilage. Cartilage is a spongy substance that covers the ends of the bones to prevent friction.

Over time, cartilage in the knee can start to wear away, particularly if a person has a knee injury or a condition such as osteoarthritis.

As the cartilage wears away, the ends of the thigh and shin bones can rub together. This can cause significant pain when someone moves or puts weight on the joint.

In comparison with traditional knee replacement, a minimally invasive TKR allows a surgeon to reconstruct the knee joint while minimizing interference with the tissue, tendons, and ligaments surrounding the knee.

Some benefits of a minimally invasive TKR include:

  • less pain after the procedure
  • a faster recovery time
  • less damage to the surrounding tissue of the knee
  • less damage to surrounding tendons, ligaments, and muscles
  • increased mobility of the knee

However, there are risks relating to these procedures, including:

  • wound breakdown
  • fracture
  • injury to ligaments
  • knee instability
  • some remaining arthritis
  • improper positioning or early loosening of components

There are several ways a person can prepare for minimally invasive TKR that a doctor may recommend:

  • avoiding alcohol for 48 hours before the procedure
  • eating a balanced, nutritious diet to increase general health
  • losing weight where necessary to reduce stress on the joints
  • avoiding or quitting smoking, if applicable
  • improving general fitness and strength to help with recovery
  • organizing a friend or family member to transport them home after the hospital stay
  • making some meals at home ahead of time that a person can reheat afterward
  • purchasing any items a person may require after the procedure to help recovery and make them more comfortable

A person may need to stop eating before midnight the night before the procedure.

They also need to let their doctor know about any medications they are taking, as they may need to stop taking them at some point before surgery.

Following a minimally invasive TKR, a person may be able to go home on the same day. Some people may require a stay in the hospital for a few days.

A person may have to wear compression socks and take blood-thinning medications to prevent blood clots after the procedure.

It may be necessary to avoid certain movements, such as bending and twisting at the knee. However, a doctor may still recommend moving around for about 5 minutes every hour. Keeping the leg raised may help reduce swelling.

Once at home, a person may need to use a crutch or cane to support them while walking. They may also have to avoid driving for several weeks and take time off from work to recover.

Recovery time following a minimally invasive TKR may vary.

A person may be able to resume daily activities within approximately 3 to 6 weeks. However, it may take several months for someone to fully recover.

A physical therapist may give a person a set of exercises that can help strengthen the knee and speed up the recovery process.

Following the post-operative advice from the surgeon may also help a person recover more quickly.

A 2020 review suggests starting rehabilitation exercises and low amounts of weight bearing on the knee joint can help reduce recovery time in the hospital following the procedure.

Exercising and weight bearing may also help speed up long-term knee recover. However, there is a limit to the amount of research in this area.

A person’s doctor or physical therapist can provide them with more information about movements and exercises that may be beneficial during recovery.

Learn more about recovery after TKR.

According to the American Academy of Orthopaedic Surgeons, the risk of complications following a minimally invasive TKR is low.

Possible complications include:

  • blood clots, which are one of the most common complications
  • scarring of knee tissue, which can reduce joint mobility
  • malfunctioning of the artificial device
  • infection in the wound or surrounding the artificial device
  • damage to the nerves or blood vessels

Learn more about the possible risks of knee replacement surgery.

A minimally invasive total knee replacement (TKR) is a surgical procedure to reconstruct the knee joint with minimal disruption to the surrounding tissue, tendons, ligaments, and muscles.

This may result in a faster recovery than traditional knee replacement surgery.

A minimally invasive TKR may be necessary if a person experiences significant knee pain, typically due to osteoarthritis.

Several ways to prepare for a minimally invasive TKR include improving fitness and strength, quitting smoking, and preparing the home.

A person’s doctor can advise on whether they recommend minimally invasive TKR, what the procedure involves, how to prepare, and what to expect during recovery.