What is TKR?
Total knee replacement was first done in 1968. Total knee Replacement is a complex procedure which require an orthopedic surgeon to make correct measurements and skillfully remove diseased portions of bone to shape remaining bone to accommodate knee’s implant. The orthopedic surgeon replaces the diseased part of knee joint with an artificial material. Knee joint is hinge joint in nature. TKR which is also known as knee arthroplasty. As both the surfaces of knee joint are replaced so it is also known as knee resurfacing.
Conditions that lead to TKR:
TKR is done when the patient is suffering from severe pain. This pain causes hindrance in his daily activities. Like stiffness which inhibits the daily routine activities, knee deformities, pain while working or at rest. Moreover, if anti inflammatory drugs are not able to treat pain then TKR is the only option. Most commonly knee pain is due to arthritis and the most common types of arthritis which leads to severe pain and in the end total knee replacement includes, Osteoarthritis, Rheumatoid arthritis, Post traumatic arthritis.
- Primary: Idiopathic
- Secondary: Post traumatic arthritis
Total knee replacement ratio:
- TKR is far more common than hip arthroplasty.
- 80% of the population going through TKR is above 75 years of age.
- TKR is found in both genders above 45-55 years in females most commonly above 55 years of age.
Risk Factors of Osteoarthritis:
- Increasing age
Depends upon the stage of involvement:
- Loss of function
- Patient’s education
- Use of assistive devices
- Weight loss
- Physical therapy
- Occupational therapy
- Glucosamine Sulfate
- Intra articular corticoids
- Intra articular hyaluronic acid
- Knee Replacement Surgery
Evolution of Total knee replacement:
- Fergusson (1860) Resection arthroplasty.
- Verneuil performed first interposition arthroplasty.
- 1940- First artificial implants were tried when molds were fitted in the femoral condyle.
- 1950-Both combined tibial and femoral articular surface replacement appeared as simple hinges.
- 1971- Frank gunstone developed a metal on plastic knee replacement.
- 1973- John insall designed what has become prototype for current TKR, this was a prosthesis made of three components which would resurface femur, tibia and patella.
Total knee Replacement Today:
Majority of knee replacements today are condylar replacements which consist of following:
- Cobalt-chrome alloy femoral component
- Titanium-tibial tray
- UHMWPE tibial bearing component
- UHMWPE patella component
Candidates for Total knee replacement:
- Quality of life severely affected
- Daily pain
- Restriction of ADLs
- Radiographic changes of knee
Time for Replacement:
- Old age with more sedentary life style
- Young patients who have limited function
- Progressive deformity
- Other modalities have failed
- Severe decrease in ROM
- Joint instability
- Muscle atrophy
Evaluation of Patient before Surgery:
- Complete Medical History
- Thorough Physical examination
- Laboratory work-up
- Anesthesia assessment
- X-rays and other lab tests
|Total knee Replacement|
Goals of Total knee replacement:
TKR is done in patients and as an outcome there is improved mobility and decreased pain in the knee joint. But range of motion and the ability to do work remains the same as that before getting diseased joint.
- Pain relief
- Restoration of normal limb movement
- Functional ROM
- Restoration of mechanical alignment
- Preservation of joint line
- Restoring normal Q- angle
Successful Goals depend on:
- Precise surgical technique
- Sound implant design
- Appropriate material
- Patient compliance with rehabilitation
- Rapid post-operative mobilization
- ROM Exercises started
- Passive extension by placing pillow under foot
- Muscle strengthening exercises
Total number of TKRs done last year near my clinical set up include 8 cases including:
- Male 5 cases
- Female 3 cases
- Age range: 40-65 years
- Cause for TKR done: Osteoarthritis