When deciding whether or not to have total knee replacement surgery, it’s important to set realistic expectations for your results.
In a survey of 266 patients, the major concerns prior to knee replacement surgery were:¹
- The ability to walk as much as you wish
- The ability to go up and down stairs
- Pain immediately after surgery
- Length of recovery
Over 90% of patients experience a significant reduction in knee pain, and greatly improved ability to perform common activities of daily living following total knee replacement surgery.²
Realistic expectations for activities following total knee replacement surgery include:
- Light hiking
- Ballroom dancing
- Various other low-impact sports
While knee replacement surgery is a major surgical procedure performed over 1,600 times a day in the United States, no surgery comes without risks.
Side effects of knee replacement surgery ³
You should know that most knee replacement surgeries are problem-free, but roughly 1 in every 20 patients may have complications—most being minor and treatable. Your complication risk depends on a number of factors, including your age and general health. Generally speaking, younger patients without other medical issues will be at a lower risk.
While some patients experience stiffness after surgery, it will typically be resolved with exercise, and as swelling improves. Pain may contribute to your level of stiffness by impeding on your ability to perform physical therapy exercises, allowing scarring to glue together the soft tissues around the joint, possibly prolonging your recovery time.
Occasionally, knee stiffness may be treated by manipulation of the joint under general anesthesia, followed by intensive physical therapy. However, this could potentially limit your range of motion.
For most patients, pain decreases during the first few months after surgery. However, some patients experience lagging pain or develop new types of pain. Research shows that 10–20% of patients continue to have moderate or severe pain past the first few months.
Blood clots forming in the deep veins in the leg —also called deep vein thrombosis (DVT)—can cause pain and swelling. Changes in the way your blood flows, and its ability to clot after surgery can lead to DVT.
Very rarely, a blood clot can travel to the lungs, leading to breathlessness and chest pains. This is called a pulmonary embolism, which in extreme cases can be fatal. However, this is usually treatable with blood-thinning drugs and oxygen therapy.
A wound hematoma results from blood collecting in a wound. While you will normally have a small amount of blood leaking from the wound after any surgery, it typically stops within a few days.
Occasionally, blood may collect under the skin and cause swelling. The blood swelling can either discharge on its own, causing a larger temporary leakage from the wound for about a week after surgery, or it may require your surgeon to remove the blood collection.
As with any operation, there’s a small risk of infection. Infections occur in about 1 in 50 cases. Typically, the infection can be treated with antibiotics. Roughly 1 in 100 patients develop a deep infection, which may require removing the new joint until the infection clears up.3
Nerve and other tissue damage
During surgery, there’s a small risk that the ligaments, arteries, or nerves could be damaged. Fewer than 1 in 100 patients end up with nerve damage, which typically improves gradually; and about 1 in 100 have some ligament damage, which is either repaired during the operation, or protected by a brace to aid healing.
While it is extremely rare, it’s possible for bone around the replacement joint to break after a minor fall. Patients with weak bones—from osteoarthritis—are at risk for this during the months and possibly years after surgery. If this occurs, further surgery is typically needed to fix the fracture and even sometimes to replace the joint components.
In cases where a mobile plastic bearing is used, there is a small risk of dislocation of the knee, for which you would require further surgery.
- Trousdale R, McGrory B, Berry D, Becker M, Harmsen W. Patients’ concerns prior to undergoing total hip and total knee arthroplasty. Mayo Clinic Proceedings
- Total Knee Replacement. Total Knee Replacement. Published August 1, 2015.
- What are the possible complications of a knee replacement? Arthritis Research UK.