Total Knee Replacement

What is Total Knee Replacement?

Total knee replacement, also known as total knee arthroplasty, is an invasive surgical procedure designed to replace a damaged knee compartment with an implant.

The knee consists of three compartments: the patellofemoral compartment (between the knee cap and thigh bone), the medial compartment (inside portion of the knee), and the lateral compartment (outside portion of the knee joint). This surgery is typically considered when arthritis or other conditions affect more than one compartment of the knee.

The main aim of total knee replacement is to restore function to the damaged knee and alleviate pain unmanageable by other treatments​​.

Total Knee Replacement Procedure

The total knee replacement procedure involves several steps to create a new, functional knee joint which can relieve pain and restore mobility.

1. Anaesthesia: The surgery is performed under spinal or general anaesthesia.
2. Incision and Bone Preparation: A small incision is made over the affected knee to expose the joint. Damaged portions of the femur (thigh bone) are cut and reshaped with the help of specialised jigs and computerised navigation.
3. Femoral Implant Placement: The femoral component is attached to the end of the femur with or without bone cement.
4. Tibial Implant Placement: The damaged part of the tibia (shinbone) and the cartilage is then cut and shaved, to create a smooth surface to attach the implants. The tibial component is secured to the reshaped tibia, potentially using bone cement.
5. Articular Surface Insertion: A plastic insert called an articular surface is placed between the implants to facilitate smooth movement and support weight, like the original meniscus cartilage.
6. Forming the New Knee Joint: The femur and the tibia, along with the new components, are put together to form the new knee joint
7. Patella Resurfacing: The rear surface of the patella (knee cap) is prepared with a plastic component to ensure smooth gliding over the artificial knee.
8. Joint Testing and Closure: The knee joint’s range of motion is tested, followed by thorough cleaning and closing of the incision.

Recovery and Rehabilitation

The recovery and rehabilitation process post-total knee replacement can help lead to optimal outcomes. Immediately after the surgery, patients are closely monitored at the hospital. The average hospital stay is 4-5 days, with some patients requiring additional time in an inpatient rehabilitation facility.

The recovery process can include:

• Using Walking Devices to Assist Knee Movement
  Initially, a walker may be used to support the knee. This usually lasts for 1 to 3 weeks. After this, crutches will be used, followed by a cane. Individuals can typically start walking on their own in 4 to 8 weeks, where a gradual return to normal activities often occurs.
• Pain and Swelling Management
  Pain and swelling may persist for 2-3 months, with leg swelling potentially lasting up to a year. This can be managed with medications and exercise techniques.
• Physical Therapy
  Exercise can help regain strength and mobility in the knee. Physical rehabilitation can extend for several months, involving exercises to enhance recovery and knee functionality.
• Avoidance of Strenuous Activities
  Certain exercises may need to be modified or avoided after a total knee replacement, including running or jogging, weight training, high-impact sports or aerobics, hiking, and skateboarding or rollerblading.

Benefits of Total Knee Replacement

The benefits of undergoing a total knee replacement include:

Pain Relief

This surgery reduces or eliminates knee pain associated with arthritis and other degenerative conditions. Patients often experience a dramatic decrease in pain levels post-surgery.

Improved Mobility and Joint Function

Total knee replacement often results in an improvement in mobility. This includes an enhanced range of motion in the knee, making it easier to perform everyday activities like walking, climbing stairs, and standing from a seated position.

Long-term Solution and Durability

Knee replacements are designed to last for many years. On average, 80-90% of knee replacements remain functional and provide pain relief for 15-20 years, making it a long-term solution for knee problems.

Risks and Complications

While total knee replacement is generally safe, it carries some risks and complications:

• Surgical Risks
  This includes bleeding, infection, and complications from anaesthesia.
  
• Blood Clots
  Risk of deep venous thrombosis, potentially leading to pulmonary complications.
  
• Issues with the Replacement Knee Joint
  Loosening, wear, or malfunction of the implant, possibly requiring revision surgery.
• Nerve or Blood Vessel Damage
  This leads to weakness, numbness, or additional surgery.
• Persistent Pain or Stiffness
  In some cases, the surgery may not fully alleviate joint pain or stiffness.
• Long-term Complications
  Including heart attacks, strokes, kidney failure, pneumonia, and other medical conditions post-surgery.