If you’re about to undergo a knee replacement procedure, you’re definitely not alone. According to an article in the medical journal Arthritis Care & Research, first-time knee replacements rose 63 percent from 1997 to 2004. Researchers predict that if these rates continue, 1.4 million knee replacements will be performed in 2015 alone!
What’s amazing about this statistic is that the total replacement of a joint was the stuff of science fiction until fairly recently. But luckily for millions of knee-pain sufferers, innovations in surgical techniques and devices have helped to make this almost commonplace in the world of orthopedics today.
So what actually happens during knee replacement surgery? Though your doctor will explain all the ins-and-outs of this procedure, here’s a quick primer on what will happen during surgery for your reference.
- First, you will go under general anesthesia for the operation. Sometimes doctors use regional nerve blocks, spinal anesthesia, or epidurals for this procedure, as well, since nerve blocks and epidurals can act as direct access points for pain meds after the surgery.
- Next, your surgeon will make a 6-8 inch incision in the front of your knee. He or she will then begin the actual replacement by removing the bone and cartilage at the bottom of the femur (the thigh bone). Next, the surgeon will remove the same material from the top of the tibia (or shin bone). He or she will do this to an exact measurement using very precise equipment, since the remaining surface must exactly “match” the design and specifications of the knee replacement device.
How your doctor chooses your implant depends on a number of factors. Because some implant makers now market directly to patients, some people will choose their own implant in conjunction with their doctor’s advice. If the surgeon chooses the implant, he or she will do it based on such things as your age, your level of physical activity, or on his or her own preference for certain types of devices. Other implants are chosen because they can better accommodate some aspect of your anatomy.
- Knee replacement implants are joined to the ends of the tibia and femur primarily in one of two ways. Either the doctor will use a special type of cement that immediately fixes the implant to the bone, or he or she will use what’s called a “press-fit” knee replacement. This type of implant has a scored or “pocked” surface that the bone can grow into as the joint heals.
The entire procedure lasts about 60-90 minutes, though you will likely be in the operating room for longer than this. You will be in the hospital for approximately 3-7 days, during which you will begin the vitally important process of rehabilitation on your new joint. You will be released from the hospital to either your own home or to a rehabilitation facility when you can:
- get in and out of bed by yourself
- bend your knee to a 90 degree angle (or are making progess towards this goal)
- straighten your leg completely
- climb 2-3 stairs and walk with crutches or a walker
- do the prescribed home exercises
Your incision site should also show no signs of infection, and your pain should be under control enough that you can successfully complete your rehabilitation exercises.
Most knee replacements last between 10 and 25 years, depending on the type of replacement, your activity level, and other factors. Some doctors even ask that you come in yearly to have the replacement checked for damage, since some devices can be repaired if they are showing signs of wear.
Arthritis Care & Research
Dr. Jonathan Cluett, About.com Orthopedics
American Academy of Orthopaedic Surgeons
Mr. Charlie Davis, Knee Replacement Patient
Total Knee Web
Published On: April 30, 2012