Risks associated with TKR
Complications following TKR is however, like with any surgery there are anesthesia related risks, exacerbation of associated medical problems and allergic reactions to medication.
Complications specific to TKR although uncommon range from minor to serious life threatening problems
Difficulty Passing Urine: occurs in 20 % of patients and may necessitate the need for a bladder catheter for a day or two.
Nausea and Vomiting is seen in the immediate post operative period in 10 % of cases.
Delayed Wound Healing: is common in obese individuals, diabetics and those who have a poor immune system. This is often seen in redo surgeries. It should be managed promptly to avoid infections.
Infection: Despite all precautions taken during surgery, infection may occur and is cited at less than 2 % of patients undergoing the procedure. This is more common in those who are elderly, diabetics, cancer patients, or on immunosuppressant medicines after transplants. Infection can be in the wound or deep seated around the implant. Some infections like MRSA (Methicillin Resistant Staphylococcus Aureus may be resistant to common antibiotics and more difficult to treat. Minor infections may be treated with antibiotics but if the implant gets infected, it may need to be removed and replaced at a later date. Infections can also occur many years after the surgery, especially in immunocompromised patients
Deep Vein Thrombosis (DVT): is a blood clot in the deep veins of the calf or top of the inner thigh. If a clot develops and breaks free, it can travel to the lungs and cause a condition known as pulmonary embolus, which is potentially life threatening. Without adequate preventive measures, the incidence of DVT is cited at 40 – 88 % and mortality due to pulmonary embolism upto 2 %. The incidence falls dramatically to less than 1 %, if DVT prophylaxis is followed. Patients of TKR will be given stockings to improve circulation and also medicines to thin blood. The physiotherapist assists in exercises and also helps the patient mobilise as soon as possible after the operation. Elevation of the limb, lower leg exercises to improve circulation also help to prevent formation of clots.
Neurovascular Injury: occurs due to pressure or injury to the nerves or blood vessels outside the knee joint and usually resolves by itself. Symptoms include tingling, numbness and rarely foot drop are known but occur in less than 0.25 % cases.
Wearing out and Loosening of Implant: The life span of a TKR is 10-20 years. Over time the knee replacement components may wear away and become loose needing surgical correction. This may also occur due to trauma, migration of the prosthesis or bone degeneration. Wearing out of the implants may be prolonged, up to about 30 years, by using the latest CERAMIC implants but these are more expensive and are beneficial in relatively younger patients (around 50yrs of age)
Stiffness: and inability to move the joint freely can usually be corrected with exercises. Although an average of 1150 range of motion is anticipated after surgery, scarring of the knee can occur limiting movement, especially in those who had limited movement before surgery. It is seen in about 10 % of patients. Treatment options are manipulation under
Continued Pain: is rare but happens in a few cases
Hematoma: in the thigh is seen in 5 % of patients where a swelling occurs due to bleeding