Knee Replacement Surgery
Knee joint replacement surgery has advanced through the years and based on the damage on the joint surface it might be necessary for both joint surfaces to be replaced in total or uni-compartmental where only one side (inside or outside) of the knee joint is replaced. The procedure is performed by separating muscles and ligaments around the knee to expose the knee capsule, and then the inside of the joint.
Knee replacement is surgery for people with severe knee damage. Knee replacement can relieve pain and allow you to be more active. Your doctor may recommend it if you have knee pain and medicine and other treatments are not helping you anymore
Arthritis Knee Joint
Arthritis destroys the cartilage covering the ends of bones. The normally smooth joint surfaces become rough and uneven. As a result, the joint cannot move smoothly. It becomes stiff, and swollen, causing pain and limited movement
Arthritis of the Knee joint may be caused by:
- age-related osteoarthritis (wear -and-tear arthritis)
- chronic inflammatory disease ( rheumatoid arthritis)
- traumatic arthritis , which can occur after a fracture or other bone injury
- some birth defects and growth disorders
Reasons for Knee Replacement (Arthroplasty)
Your general practitioner and orthopaedic surgeon may recommend knee replacement surgery in the following cases:
- chronic pain that has not been relieve by anti-inflammatory medications, physical therapy, and the use of a cane or other devices
- pain is so severe that it restricts work, walking, recreation, and daily activities
- sleep is disturbed due to night pain
- the knee is very stiff and may be swollen
- X-Ray examination confirms advanced arthritis
- avascular necrosis ( a lack of blood supply to the ends of the bones) has damaged the joint; it is usually caused by trauma
Total Knee Joint Replacement Operation
In a knee replacement operation, the surgeon removes the worn ends of the bones and any remaining hard cartilage and replaces them with metal and plastic parts. The end of the thigh bone (femur) is replaced by a single curved piece of hard metal. The top end of the shin bone (tibia) is replaced by a flat plate of metal fixed into the bone. A plastic bearing is fitted to this plate to act like hard cartilage. The surgeon usually has to adjust the ligaments of the knee to make way for the new joint and to correct any deformity. The interlocking parts of the new metal and plastic parts allow the knee to bend while also making it more stable.
There are several different kinds of knee replacement operations as well as many different designs for the parts or implants (prostheses) used.
There are also alternative surgical options. Your doctor and surgeon should help you to choose the best solution for you, taking into account the condition of your knee and your general health. In making your decision, you may want to ask for information about the long-term outcomes of a particular operation or a particular design of implant. Knowing that the option you choose has been successfully tried and tested over a reasonable period should give you peace of mind.
Unicompartmental/ Partial Knee Replacement
Unicompartmental knee arthroplasty is a minimally-invasive procedure to replace part of the knee’s compartments Medial, Lateral or Patella- femoral to restore function and manage pain. Because only part of the damaged knee is replaced, it is often called a partial knee replacement.
Today, the procedure offers many benefits over total knee replacement:
- A smaller incision. The incision used in Unicompartmental Knee joint Replacement is about 2 to 3 times smaller than the one required by total knee replacement. A smaller cut means less blood loss, less tissue damage, and a faster recovery.
- Better range of motion after surgery.
- Shorter hospital stay.
- Costs less. Unicompartmental Knee joint Replacement costs about half that of total knee replacement.
- If needed, the implant can be easily converted to a total knee replacement.
Pain relief is the same for both procedures.
Knee Joint Replacement Post Operation Instructions
As a general guide to post-operative rehabilitation after Knee Joint surgery, the following are offered as guidelines.
Exercises
Some exercises are particularly helpful in restoring muscle tone and as an aid to resuming activity.
- Using your crutches for balance: Swing the affected leg forwards and backwards in a straight line position – 10 – 20 times , 2 or 3 times a day – to an angle of 25 – 30 degrees.
- Practice straight leg raising while in bed, lifting the leg off the bed to an angle of 15 – 30 degrees. It is important to maintain the bend in the knee.
- The physiotherapist will instruct you in exercises to do this. It is often uncomfortable to push the bend but it is necessary and important that adequate movement is achieved.
Walking
- Walk using your crutches on a smooth even surface, at a steady even pace. Take even steps and wear comfortable supportive footwear with a low heel. You will need BOTH CRUTCHES for approximately 3-5 weeks after Knee Joint surgery.
- Your walking distance can be steadily increased. If you feel you have overdone things ( e.g. Some muscular or bone pain or discomfort) rest more for a day or so.
- Target distances will vary, but provided you feel strong enough and are not suffering pain or discomfort, total DAILY distances can be:
- Week 1 – up to 0.5 km after Knee Joint surgery
- Week 2 – up to 1 km after Knee Joint surgery
- Week 3 – up to 3 km after Knee Joint surgery
- Week 4 – up to 4 km after Knee Joint surgery
- Week 5 – up to 5 km after Knee Joint surgery
- DO NOT EXTEND OR STRAIN YOURSELF – MORE IS NOT NECESSARILY BETTER.
Pain and Discomfort
Both bone and tissue (muscle, nerves, tendons, ligaments) are undergoing a healing process that will not be complete for several weeks after the operation. (Healing is generally complete in 10 – 12 weeks). As the knee joint is close to the skin surface, the knee is often warm for some months following surgery. This is part of the normal healing. After you have left hospital there is still commonly felt pain and discomfort. It can take the following forms and unless it persists or is severe is not a cause for concern or anxiety.
- Soreness / Pain Around the Scar caused by tissue/scar/repair, and as a result of the exercise.
- Sudden sharp, needle-like pain in tissue Caused by tissue repairing and nerves regaining viability
- Aching Pain ( feels as if in bone) Caused by excessive exercise or by e.g. sitting or lying in an inappropriate way.
- There is usually some loss of skin sensation on the outer aspect of the scar. This occurs because of division of a nerve supplying this area necessary when the knee is approached from the front.
- Swelling and Warmth It is common for the knee to remain warm and swollen for many months. This may increase with exercises. However, the wound should remain dry.
- Excess swelling and pain in the calf may require an ultrasound to exclude a blood clot.
Do’s and Dont’s
- For the first 2-3 weeks after Knee Joint surgery you will need assistance in putting onand removing clothing and garments (underpants, panties, trousers, slacks or similar, socks,stockings and footwear. )
- Do not try to carry items WHILST USING BOTH CRUTCHES – it can cause you to lose your balance.
- If your wound becomes increasingly red or oozes, then contact myself or your GP.
- Use both crutches inside and outside for the first 3 – 4 weeks after Knee Joint surgery.
- After 3 – 4 weeks you may find that around the house or office you can move safely and comfortably with one crutch or a stick, or no crutches.
- Avoid public and thermal pools for a minimum of 3 weeks.
- IF IN DOUBT ASK FOR GUIDANCE
Gender Specific Knee Replacements
Research has shown differences in the bony anatomy between women and men, which is why my techniques accomodate gender specific implants and techniques.
The gender specific implant has an excellent 10-year track record, so it offers the best of all worlds – a highly successful implant with high flexion capabilities and has seen a definite improvement in the patients shortened recovery and rehabilitation and better long term results.
Metal Sensitivity Management and Implant Durability
Most implants are made from Cobalt Chrome, Titanium Alloy and a plastic/ polyethylene interface which acts as a buffer between the metals. Some of these metals has a nickel content which is usually the element responsible for metal allergy or sensitivity.
A new material, called Oxinium was designed in order to manage metal allergy but simultaneously address survivorship and the main reason for implant failure, Polyethylene wear.
Oxinium is a black, hardened metal with no nickel content and has the potential to last up to 30 years when used in conjunction with a specially treated plastic liner.
For more information about Knee Replacement please discuss with your doctor.
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