Knee prosthesis
Is a replacement of the knee joint. The surgeon removes the damaged cartilage and bone and replaced by an artificial prosthesis formed by a combination of metal and an insert made of polyethylene enabling mobility.
The orthopedic surgeon will assess when to the joint replacement. “Over 90% people who undergo surgery total knee replacement experience a dramatic reduction of knee pain and a significant improvement in the ability to perform common activities of daily living”. American Academy of Orthopedic Surgeons (AAOS).
Prosthetic knee replacement can last for many years, however, are subject to wear with use, normal activities and low impact sports. Most surgeons discourage high impact activities after implantation.
The rate of complications after a total knee implant is low. Solo in less than 2 hundred patients serious complications occur, as infection of the knee joint. Major medical complications, as a heart attack, still occur less frequently. (Source: American Academy of Orthopedic Surgeons (AAOS).
Knee arthroplasty is a replacement of the bone surface.
It takes place in four stages:
- Preparation. Damaged cartilage fragments on the ends of the femur and the tibia is removed and also a small portion of the surrounding bone.
- Thumbnail metallic implants. Cartilage and bone are replaced damaged by metallic elements that reconstruct the joint surface.
- Resurfacing of the patella. The lower surface of the patella is cut and a button resuperficializa thermoplastic.
- Inserting a spacer. If you insert a thermoplastic spacer (polyethylene) between the metal elements to favor sliding.
When replacement is indicated
Knee replacement is indicated when pain is experienced much, knee is stiff and has lost mobility, there is a deformity of the knee or a chronic inflammation that does not improve with rest or medications.
Recovery
After a brief stay in the hospital, the patient recovers at home. This requires having prepared your home to make it easier to get around it. There are a number of elements that can make everyday activities:
- A stable chair with a pillow on the seat, strong support and armrests.
- A stool where to place intermittently raised leg.
- Placing safety bars or handrails in the shower or in the bathtub.
- A stable bank for the shower chair for bathtub.
- Handrails on stairs.
- Armrest to get off the toilet.
It is also advisable:
- Remove carpets and loose wires.
- Gather everything you need for everyday living on one floor, to avoid climbing stairs, at the beginning of the recovery.
After surgery
Follow your orthopedic surgeon's instructions. It is necessary to care for the wound, avoid submerging the wound in water until it is completely healed; maintain a balanced diet and do exercise the doctor has indicated. Exercise is a critical component for recovery. It is advisable to walk again as gradually progressive daily regimen in order to gradually increase the mobility. And back to normal domestic activities, as sitting, stand and climb stairs. We strongly recommend that the prescribed exercises several times a day to restore movement and strengthen the knee. You can do them at home or with the help of a physiotherapist in a recovery center.
Prevention of clot formation
If you carefully follow the instructions of the orthopedic surgeon can reduce the risk of blood clots from forming during the first weeks of recovery. Tell your doctor immediately if:
- If you feel pain or pressure no redness above or below the knee.
- Increases calf pain.
- Becomes swollen calf, ankle or foot.
- Suddenly having trouble breathing.
- Feel a sudden chest pain.
Prevention of infection
After undergoing a knee replacement is advisable to take preventive antibiotics before dental or surgical procedures that would facilitate the entry of bacteria into the blood and cause an infection. Tell your doctor immediately if:
- Have persistent fever (over 37 ° C).
- Increased redness, pressing pain, or inflammation of the knee injury.
- A discharge is produced in the wound.
Prevention of falls
The consequences of a fall during the first weeks after knee replacement could be dire. Following the advice orthopedic surgeon and physical therapist use crutches, a cane to a walker, always hold on to the railing and avoid as far as possible the stairs until your knee is strong.
Training
Replacement knee prosthesis (Revision surgery for knee arthroplasty)
Replacement of a total knee replacement that is loose is one of the most complex interventions in orthopedic surgery. Usually they fail to aflojamiento aseptic infection by the, but can also be a painful prosthesis stiffness, in the extensor mechanism problems, instability and other. The most frequent causes parts of a knee prosthesis are:
- mechanical loosening
- infection in the joint
- fracture of the bone near the joint
- instability of the implant (dislocation of the joint)
- tear of a part (o más) implant
- implant breakage
Early failures are due to misplacement or infection. Failures after 15 or more years are due to loss of the polyethylene liner delamination, loose particles that trigger an inflammatory reaction that ends bone prosthesis loosening. The replacement of a prosthesis on the other makes it very difficult for several reasons, may have occurred:
- a large bone loss requiring the use of grafts,
- stiffness and contracture of the soft tissues that are difficult to release and balance,
- tendons loss requiring transplants,
- a difficulty in closing wounds requiring twin plasty and skin grafting.
The replacement of a knee prosthesis is a procedure of high complexity and should be performed by a skilled surgeon and accustomed to this type of surgery.