Osteoarthritis of the knee causes deterioration of the ends of the upper and lower leg bones. Cartilage is destroyed, and eventually bone rubs on bone, causing pain and instability of the knee. Knee replacement surgery involves replacing the destroyed bone with an artificial joint made of metal alloys, high-grade plastic and polymers. According to the Mayo Clinic, serious complications are rare in knee surgery, and fewer than 2 percent of patients have significant complications. As with any surgery, a patient should be aware that there is the potential for lack of good range of motion, nerve damage, non-healing wounds and loosening of the joint after surgery.
Lack of Range of Motion
The natural tendons and ligaments of the leg, if damaged prior to surgery, may prevent the knee from having full range of motion. PeaceHealth.org states that if the knee was not bending well prior to surgery, it will probably not bend well after surgery. Physical therapy can help, as well as weight control and daily walking. Occasionally, patients will build up excessive scar tissue after surgery, and this will prevent full range of motion of the knee.
Nerve Damage
The peroneal nerve can be damaged during surgery. This is the nerve that lifts the foot toward the face when walking. This is usually not a permanent injury, and is caused by increased swelling or vigorous retraction during surgery. According to The Hip and Knee Institute, this type of nerve injury usually resolves within six to 12 months.
Non-Healing Wound
If the skin around the knee fails to heal properly, some of it may slough off. This can be a catastrophic complication if the new joint is exposed. Exposure sets up the joint for infection. Skin grafts or a muscle rotation to cover the exposed joint may be required. Legs that are heavy are more likely to have this complication.
Loosening of the Joint
The new joint is cemented onto the natural bone. How long the bond lasts depends on several factors. According to The Hip and Knee Institute, how well the surgery is done is the most important factor. Having a surgeon who does only knee surgeries can have an impact on how well the surgery is performed. The quality of the patient's bones is another factor. If the bones are hard--not riddled with osteoporosis or soft--the bond will last longer. Participating in low-impact exercise can lengthen the life of the joint. Maintaining an appropriate weight can help prolong the life of the bond.
