Injury or arthritis can damage your knee and make it difficult to walk, climb stairs or do other simple tasks. The condition may worsen and lead to pain even when lying down or sitting. While nonsurgical remedies such as medications and walking aids can help, you may reach a point where you require knee replacement surgery. Few complications occur, but if they arise, they may slow down and limit recovery.
What Are the Possible Complications of Knee Replacement?
1. Blood Clots
Thrombosis (blood clots) is one of the leading knee replacement complications. In some cases, the blood clots may move to the heart and the lungs. Following surgery, doctors often prescribe blood thinning medications as a preventive measure. Exercises such as compressive calf cuffs will also help prevent blood clots.
2. Bleeding and Wound Haematoma
While it is normal for the surgery wound to bleed slightly for up to a day or two, blood may collect under the skin, forming a swelling or wound hematoma. The blood in the hematoma may leak until it is fully cleared in about a week. In other cases, the blood will require an incision to drain it. The risk of hematoma may increase with the use of drugs such as aspirin and some antibiotics after surgery.
3. Infection
Knee replacement surgery is conducted in an operating room with sterile instruments to keep away infections. Additionally, the patient is given antibiotics as a precautionary measure. However, post-operative infection may still occur, but it is more likely in patients with diabetes, rheumatoid arthritis, those who had an infection before the procedure and those who have been on cortisone for a long time.
4. Adhesions
Scar tissues (adhesions) can form following knee replacement surgery. These may affect flexibility of the knee joint. A patient who gets excessive adhesions (arthrofibrosis) may need to undergo a procedure known as manipulation under anesthesia to improve mobility.
5. Misalignment
In rare cases where improperly angled cuts are made during surgery, or incorrect implants are used, misalignment may occur, which will present with post-operative pain. These rare cases are more likely to occur if the surgeon does not have sufficient experience. For this reason, choose a surgeon who is well versed with the procedure.
6. Implant Loosening
Implant loosening is one of the most worrying knee replacement complications. It may arise due to poor technique during surgery, bones damaged by rheumatoid arthritis, osteoporosis, obesity or extreme force in an accident. The most common cause, however, is faulty knee replacement technique. Before undergoing knee replacement surgery, do your research and choose an experienced knee surgeon.
7. Instability of Ligaments
In case ligaments are damaged or not properly fixed during surgery, the knee may be unstable. When this happens, movement may be affected so that the knee does not operate correctly. In most cases, this will improve once the ligaments recover, but in some cases knee braces may be needed to stabilize the knee following surgery.
8. Allergic or Other Reactions
In rare cases, some patients develop allergies to the metals used in the implants. To avoid this, a patient who is allergic to any metal should undergo a preoperative exposure test. Ceramic-coated implants have been developed to prevent contact between the metallic parts and body tissues.
9. Nerve Damage
Sometimes, nerve damage can occur during knee replacement surgery. In most such cases, the damaged nerves get back to normal within months to one year. It is also common to feel numb in the frontal knee skin and the incision area. But this will relieve with time.
10. Complications from Anesthesia
During surgery, the operating team will use general or local anesthesia so that you don’t experience any pain. While the anesthetic is generally safe, it may lead to some adverse reactions, including:
- dizziness
- vomiting
- sore throat
- shivering
- discomfort
- aches and pains
- drowsiness
- gastric problems
- dental trauma
- vocal cord injury
- allergic reactions to latex
- wheezing
- injury to nerves, arteries or veins
- irregular heartbeat
Discuss your medical history with the surgeon prior to surgery to allow for proper preparation and prescription. Be open about your indulgence in alcohol, smoking and recreational drugs.
11. Complications from a Transfusion
You may need a blood transfusion during total knee replacement surgery. While the risk of complication is slim, there is still a one in 14,000 chance of a hemolytic transfusion complication. When this reaction occurs, symptoms such as the following will appear in the first 24 hours following surgery.
- fever
- chills
- hives
- red urine
- shortness of breath
In some cases, you may be advised to give your own blood in advance for use during your surgery. Consult your surgeon to find out if this is necessary.
12. Osteolysis
Knee replacement complications arising from the plastic particles of the implant are known as osteolysis. The plastic particles cause the body’s defenses to react, producing white blood cells to destroy the foreign bodies. This reaction may lead to destruction of parts of bone, causing loosening of the implant. The complication is more likely when polyethylene implants have been used. While a polyethylene implant enables more natural knee joint replacement, the material is more likely to wear out, necessitating another surgery.
13. Bone Fracture
Bone fracture can sometimes occur in the area around the implant. This rare complication may result from a fall. It may also occur in a patient with osteoporosis (weak bones). A surgical procedure is normally required to fix such a fracture.
14. Pulmonary Embolism
On a few occasions, a blood clot may form in the knee and end up in the lungs, causing pulmonary embolism. This is usually cleared using blood thinning medications and oxygen therapy; however, in rare cases pulmonary embolism may cause death.
Other possible complications include stroke, congestive heart failure, cardiac arrhythmia, hyperglycemia and hemorrhage.
How to Reduce Complications of the Surgery
Following are tips to reduce risk of knee replacement complications:
- Relieve pain. You will get a prescription for pain relief. Pain management will help you become more active, which will in turn promote speedy recovery.
- Use ice. Holding an ice pack on the affected knee will reduce pain and swelling in the first days following surgery. Supporting your leg on a few pillows will also reduce swelling.
- Try compression devices. Your doctor may recommend use of compression devices such as stockings and boots to prevent complications. These apply pressure which prevents pooling and clotting of blood.
- Clean the wound. Follow the instructions given on care of the wound. You will prevent infection by keeping the site clean.
- Take it slow. You will need to rest for several days following surgery. It will take up to six weeks before you can resume your normal physical routine including driving and climbing stairs.
- Exercise. Getting out of bed and exercising as advised by your doctor will get the knee working sooner. It will also prevent the formation of blood clots.